Patent Application
20230243949
This application relates to the field of sensor technologies, and more specifically, to a radar ranging method and an apparatus in the field of sensor technologies.
With development of society and progress of science and technology, intelligent vehicles gradually enter people's daily life. A sensor plays a very important role in unmanned driving and intelligent driving of the intelligent vehicle. The sensor may include a millimeter-wave radar, a laser radar, an ultrasonic radar, a camera, and the like.
A ranging principle of a radar ranging apparatus is as follows: A transmitter of the radar ranging apparatus sends a radar signal, a receiver of the radar ranging apparatus receives an echo signal that corresponds to a target in a vision scope and that is generated when the radar signal is reflected by the target, and a distance between the target and the radar ranging apparatus is calculated by measuring delay time from time for sending the radar signal to time for receiving the echo signal of the target.
However, during actual application, because a part of signals may be reflected back by an inner wall or a window of the radar ranging apparatus in a radar signal transmission process, a spurious echo signal is generated. In this way, echo signals received by the receiver may include both the echo signal of the target and the spurious echo signal. In other words, the spurious echo signal causes interference to the echo signal of the target. Consequently, accuracy of performing ranging on the target by using the echo signals received by the receiver is low.
Embodiments of this application provide a radar ranging method and an apparatus, to improve accuracy of radar ranging.
According to a first aspect, an embodiment of this application provides a radar ranging method, and the method may be applied to a radar ranging apparatus. The method may include: The radar ranging apparatus sends a first radar signal from a first field of view through a first transmitter. The radar ranging apparatus receives a first echo signal of the first radar signal from the first field of view through a first receiver, where the first echo signal includes an echo signal of a first target, and the first transmitter and the first receiver belong to a first radar channel. The radar ranging apparatus performs ranging processing on the first target based on the echo signal of the first target. The first echo signal further includes a spurious echo signal, the spurious echo signal includes an echo signal generated when the first radar signal is reflected by an obstacle, at least one first signal parameter of the spurious echo signal corresponds to at least one of an identifier of the first radar channel and the first field of view, and the at least one first signal parameter includes at least one of an amplitude at at least one first sampling moment and first delay time.
According to the radar ranging method provided in this embodiment of this application, the at least one first signal parameter corresponding to the identifier of the first radar channel and the first field of view is obtained based on at least one of the identifier of the first radar channel and the first field of view, the spurious echo signal is determined based on the at least one first signal parameter, the spurious echo signal is canceled from the first echo signal to obtain the echo signal of the first target, and the ranging processing is performed on the first target based on the echo signal of the first target. In this way, interference and impact of the spurious echo signal on the echo signal of the first target can be avoided, in other words, purity of the echo signal of the first target can be improved, and therefore accuracy of radar ranging can be improved.
Optionally, the obstacle may include an object inside the radar ranging apparatus and/or an object outside the radar ranging apparatus. This is not limited in this embodiment of this application.
In a possible implementation, the obstacle may include at least one of an inner wall, a window, or an internal circuit of the radar ranging apparatus.
In another possible implementation, the obstacle may include an object, outside the radar ranging apparatus, other than the first target.
In a possible implementation, the first radar signal may be an optical pulse signal.
The following describes, in two cases, a process in which the radar ranging apparatus performs ranging processing on the first target based on the echo signal of the first target.
Case 1: The radar ranging apparatus includes only the first radar channel. In other words, the spurious echo signal includes the echo signal generated when the first radar signal is reflected by the obstacle.
Correspondingly, the radar ranging apparatus may determine the at least one first signal parameter of the spurious echo signal based on at least one of the identifier of the first radar channel and the first field of view, determine the spurious echo signal based on the at least one first signal parameter, cancel the spurious echo signal from the first echo signal to obtain the echo signal of the first target, and perform ranging processing on the first target based on the echo signal of the first target.
Optionally, the radar ranging apparatus may determine the at least one first signal parameter in a plurality of manners based on at least one of the identifier of the first radar channel and the first field of view. This is not limited in this embodiment of this application.
In a possible implementation, the at least one first signal parameter may correspond to only the first field of view, in other words, the first field of view and the at least one first signal parameter may meet a predefined first mapping relationship.
Correspondingly, the radar ranging apparatus may determine the at least one first signal parameter based on the first field of view and the first mapping relationship.
In another possible implementation, the at least one first signal parameter may correspond to the first field of view and the identifier of the first radar channel, in other words, the first field of view, the identifier of the first radar channel, and the at least one first signal parameter may meet the predefined first mapping relationship.
It should be noted that the at least one first signal parameter may include at least one of the amplitude at the at least one first sampling moment and the first delay time. The at least one first sampling moment may be understood as at least one sampling moment of the spurious echo signal, and the first delay time may be understood as a time difference from transmitting the first radar signal to receiving the spurious echo signal.
For example, the first delay time T1 represents a time difference from a start moment to for transmitting the first radar signal to a start moment t1 for receiving the spurious echo signal, and the amplitude at the at least one first sampling moment may include an amplitude A1 at a moment t2, an amplitude A3 at a moment t3, and an amplitude A2 at a moment t4.
In a possible implementation, when the at least one first signal parameter includes an amplitude at one first sampling moment, the radar ranging apparatus may determine the spurious echo signal based on the amplitude at the first sampling moment and preset waveform information of the spurious echo signal, where the waveform information indicates a waveform of the spurious echo signal.
For example, the at least one first signal parameter includes an amplitude Amax at a wave peak of the spurious echo signal at a first sampling moment t1. The radar ranging apparatus may determine, based on a schematic diagram of the waveform of the spurious echo signal and the amplitude Amax at the first sampling moment t1, an amplitude of the spurious echo signal at a first sampling moment other than the first sampling moment t1, to determine the spurious echo signal.
In another possible implementation, when a quantity of the at least one first signal parameter is greater than 1, and the at least one first signal parameter includes amplitudes at a plurality of first sampling moments, the radar ranging apparatus may perform difference processing on the amplitudes at the plurality of first sampling moments by using a difference algorithm, to determine the spurious echo signal.
For example, the at least one first signal parameter includes an amplitude A1 of a leading edge of the spurious echo signal at a first sampling moment t2, an amplitude Amax at a wave peak of the spurious echo signal at a first sampling moment t3, and an amplitude A2 of a trailing edge of the spurious echo signal at a first sampling moment t4. The radar ranging apparatus may calculate a difference based on amplitudes at the three first sampling moments, determine an amplitude of the spurious echo signal at a first sampling moment other than the first sampling moment t2, the first sampling moment t3, and the first sampling moment t4, to determine the spurious echo signal.
Optionally, that the first field of view, the identifier of the first radar channel, and the at least one first signal parameter meet the predefined first mapping relationship is used as an example. Before determining the at least one first signal parameter of the spurious echo signal based on at least one of the identifier of the first radar channel and the first field of view, the radar ranging apparatus may obtain at least one mapping relationship. The at least one mapping relationship includes the first mapping relationship, and the at least one mapping relationship indicates a correspondence between an identifier of a radar channel, a field of view, and a first signal parameter.
Correspondingly, the radar ranging apparatus may obtain, based on the at least one mapping relationship, the at least one first signal parameter corresponding to the identifier of the first radar channel and the first field of view.
Optionally, the radar ranging apparatus may obtain the at least one mapping relationship in a plurality of manners. This is not limited in this embodiment of this application.
In a possible implementation, the radar ranging apparatus may preconfigure the at least one mapping relationship.
In another possible implementation, the radar ranging apparatus may receive the at least one mapping relationship from another apparatus in advance.
In still another possible implementation, the radar ranging apparatus may generate the at least one mapping relationship.
Optionally, the at least one mapping relationship may be represented in a plurality of forms. This is not limited in this embodiment of this application.
In a possible implementation, a mapping table 1 represents at least one mapping relationship between an identifier of a radar channel, a field of view, and a signal parameter.
According to the radar ranging method provided in this embodiment of this application, a statically set mapping table is queried based on at least one of the identifier of the first radar channel and the first field of view, the at least one first signal parameter corresponding to the identifier of the first radar channel and the first field of view is obtained based on the mapping table, the spurious echo signal is determined based on the at least one first signal parameter, the spurious echo signal is canceled from the first echo signal to obtain the echo signal of the first target, and the ranging processing is performed on the first target based on the echo signal of the first target. In this way, the interference and the impact of the spurious echo signal on the echo signal of the first target can be avoided, in other words, the purity of the echo signal of the first target can be improved, and therefore the accuracy of radar ranging can be improved.
It should be noted that, because the amplitude at the first sampling moment and/or the first delay time may change with an operating temperature of the radar ranging apparatus, the at least one first signal parameter may represent a signal parameter at a first operating temperature, in other words, at least one of the identifier of the first radar channel and the first field of view, the first operating temperature, and the at least one first signal parameter may meet a predefined first mapping relationship.
Correspondingly, the radar ranging apparatus may determine the at least one first signal parameter based on the first operating temperature and at least one of the identifier of the first radar channel and the first field of view.
For example, a mapping table 2 indicates at least one mapping relationship between an identifier of a radar channel, a field of view, a signal parameter, and an operating temperature.
It should be further noted that, because the mapping table 2 needs to include a first signal parameter at each operating temperature, and therefore the radar ranging apparatus needs to store a large amount of data, it may be considered that only a first signal parameter at a standard operating temperature is stored, and a variation value of a first signal parameter at another operating temperature compared with the first signal parameter at the standard operating temperature is incrementally stored, so that an amount of stored data can be reduced.
For another example, a mapping table 3 indicates a radar channel, a field of view, an operating temperature, a signal parameter, and incremental information, where the incremental information indicates a change of a signal parameter at a different operating temperature compared with a signal parameter at a standard operating temperature.
According to the radar ranging method provided in this embodiment of this application, a statically set mapping table is queried based on the current first operating temperature and at least one of the identifier of the first radar channel and the first field of view, the at least one first signal parameter corresponding to the first operating temperature and the identifier of the first radar channel and/or the first field of view is obtained based on the mapping table, the spurious echo signal is determined based on the at least one first signal parameter, the spurious echo signal is canceled from the first echo signal to obtain the echo signal of the first target, and the ranging processing is performed on the first target based on the echo signal of the first target. In this way, the interference and the impact of the spurious echo signal on the echo signal of the first target can be avoided, and therefore the accuracy of radar ranging can be improved.
Case 2: The radar ranging apparatus includes a plurality of radar channels, and at least two of the plurality of radar channels belong to different signal transceiver groups.
Optionally, that the plurality of radar channels include the first radar channel and a second radar channel, and the second radar channel includes a second transmitter is used as an example. Before performing ranging processing on the first target based on the echo signal of the first target, the radar ranging apparatus may further send a second radar signal from a second field of view through the second transmitter.
In other words, the spurious echo signal includes a first spurious echo signal generated when the first radar signal is reflected by the obstacle and a second spurious echo signal generated when the second radar signal is reflected by the obstacle.
Correspondingly, the radar ranging apparatus may determine at least one first signal parameter of the first spurious echo signal based on at least one of the identifier of the first radar channel and the first field of view, determine the first spurious echo signal based on the at least one first signal parameter, determine at least one second signal parameter of the second spurious echo signal based on at least one of an identifier of the second radar channel and the second field of view, determine the second spurious echo signal based on the at least one second signal parameter, cancel the first spurious echo signal and the second spurious echo signal from the first echo signal to obtain the echo signal of the first target, and perform ranging processing on the first target based on the echo signal of the first target.
Optionally, the first field of view and the second field of view may be the same, or may be different. This is not limited in this embodiment of this application.
It should be noted that, for a process in which the radar ranging apparatus determines the at least one second signal parameter of the second spurious echo signal based on at least one of the identifier of the second radar channel and the second field of view, refer to the process in which the radar ranging apparatus determines the at least one first signal parameter of the spurious echo signal based on at least one of the identifier of the first radar channel and the first field of view in the case 1. To avoid repetition, details are not described herein again.
It should be further noted that, for a process in which the radar ranging apparatus cancels the first spurious echo signal and the second spurious echo signal from the first echo signal to obtain the echo signal of the first target, refer to the process in which the radar ranging apparatus cancels the spurious echo signal from the first echo signal to obtain the echo signal of the first target in the case 1.
Optionally, the radar ranging apparatus may cancel target spurious echo signal from the first echo signal in a plurality of manners, to obtain the echo signal of the first target. This is not limited in this embodiment of this application.
In a possible implementation, that the spurious echo signal includes P sampling moments, the P sampling moments correspond to P first amplitudes on the spurious echo signal, the first echo signal includes the P sampling moments and Q sampling moments, the P sampling moments correspond to P second amplitudes on the first echo signal, the Q sampling moments correspond to Q third amplitudes on the first echo signal, and both P and Q are integers greater than 0 is used as an example. The echo signal of the first target may include the P sampling moments and the Q sampling moments. The P sampling moments correspond to P target amplitudes on the echo signal of the first target, and a target amplitude corresponding to each of the P sampling moments is a difference between a first amplitude and a second amplitude. The Q sampling moments correspond to the Q third amplitudes on the echo signal of the first target.
According to a second aspect, an embodiment of this application further provides a radar ranging method, and the method may be applied to a radar ranging apparatus. The method may include: The radar ranging apparatus sends a first radar signal through a first transmitter. The radar ranging apparatus receives a first echo signal of the first radar signal through a first receiver, where the first echo signal includes an echo signal of a first target. The radar ranging apparatus receives a second echo signal of the first radar signal through a second receiver, where the second receiver is located outside a primary signal transmission path between the first transmitter and the first receiver. The radar ranging apparatus performs ranging processing on the first target based on the first echo signal and the second echo signal. The second echo signal is used to determine a target spurious echo signal corresponding to an obstacle, and the echo signal of the first target does not include the target spurious echo signal.
According to the radar ranging method provided in this embodiment of this application, the radar ranging apparatus can cancel, based on a second spurious echo signal received in real time, the target spurious echo signal corresponding to the obstacle from the first echo signal, so that interference caused by the spurious echo signal to the echo signal of the first target can be reduced, in other words, purity of the echo signal of the first target can be improved, and therefore accuracy of radar ranging can be improved.
In other words, the primary signal transmission path between the first transmitter and the first receiver includes the first target, and therefore the first echo signal received by the first receiver includes the echo signal of the first target. In addition, the second receiver is located outside the primary signal transmission path, and therefore the second echo signal received by the second receiver does not include the echo signal of the first target.
Optionally, the radar ranging apparatus may include a first signal transceiver group and a second signal transceiver group. The first signal transceiver group includes the first transmitter and the first receiver. The second signal transceiver group includes the second receiver and a second transmitter, and the radar ranging apparatus does not send a radar signal through the second transmitter. Alternatively, the second receiver may be a receiver additionally disposed outside the primary signal transmission path between the first transmitter and the first receiver. This is not limited in this embodiment of this application.
For example, the first transmitter may be an LD, the first receiver may be an APD, and the second receiver may be a photodiode (positive intrinsic-negative, PIN).
Optionally, the obstacle may include an object inside the radar ranging apparatus and/or an object outside the radar ranging apparatus. This is not limited in this embodiment of this application.
In a possible implementation, the obstacle may include at least one of an inner wall of a housing, a window, or an internal circuit of the radar ranging apparatus.
In another possible implementation, the obstacle may further include an object, outside the radar ranging apparatus, other than the first target.
Optionally, that the radar ranging apparatus performs ranging processing on the first target based on the first echo signal and the second echo signal may include: The radar ranging apparatus determines the target spurious echo signal corresponding to the obstacle based on the second echo signal, cancels the target spurious echo signal from the first echo signal to obtain the echo signal of the first target, and performs ranging processing on the first target based on the echo signal of the first target.
It should be noted that, because a scattering phenomenon may occur in a propagation process of the first radar signal, a part of scattered signals may be reflected to the second receiver by the obstacle, for example, the inner wall, the window, or the circuit inside the radar ranging apparatus. In other words, the second echo signal received by the second receiver may include a first spurious echo signal corresponding to the obstacle, and the first echo signal received by the first receiver may further include the second spurious echo signal corresponding to the obstacle.
However, because the first receiver and the second receiver are located at different locations, delay time and/or amplitudes of the first spurious echo signal and the second spurious echo signal may be different. Therefore, when the first spurious echo signal is directly used to cancel the second spurious echo signal from the first echo signal, incomplete cancellation (in other words, purity of the echo signal of the first target that is obtained after cancellation is low) or excessive cancellation (in other words, a part of the echo signal of the first target that is obtained after cancellation is missing) may exist, resulting in poor accuracy of radar ranging performed based on the echo signal of the first target.
Optionally, the radar ranging apparatus may determine, based on the first spurious echo signal, the target spurious echo signal corresponding to the obstacle, where the target spurious echo signal may be considered to be the most similar to the target spurious echo signal in the first echo signal; and cancel the target spurious echo signal from the first echo signal to obtain the echo signal of the first target.
In a possible implementation, the radar ranging apparatus may correct the first spurious echo signal based on the first echo signal, to obtain the target spurious echo signal.
Optionally, the radar ranging apparatus may correct the first spurious echo signal based on the first echo signal in a plurality of manners, to obtain the target spurious echo signal. This is not limited in this embodiment of this application.
In a possible implementation, the radar ranging apparatus may adjust delay time of the first spurious echo signal a plurality of times to obtain a plurality of first adjusted signals, determine a ratio of an amplitude of the first echo signal at a first sampling moment to an amplitude of each of the plurality of first adjusted signals at the first sampling moment as an amplitude coefficient of each first adjusted signal, multiply each first adjusted signal and the amplitude coefficient of each first adjusted signal to obtain a plurality of second adjusted signals, and determine the target spurious echo signal based on the plurality of second adjusted signals and the first echo signal.
Optionally, when the second spurious echo signal in the first echo signal and a first target echo signal are not superimposed, the first sampling moment may be any sampling moment on the second spurious echo signal. Alternatively, when the second spurious echo signal in the first echo signal and a first target echo signal are superimposed, the first sampling moment may be a sampling moment corresponding to a peak of the second spurious echo signal or a sampling moment on a leading edge of the second spurious echo signal. Alternatively, when saturation exists on the second spurious echo signal, the first sampling moment may be a sampling moment on a leading edge of the second spurious echo signal except a saturation interval.
In a possible implementation, that the radar ranging apparatus determines the target spurious echo signal based on the plurality of second adjusted signals and the first echo signal may include: The radar ranging apparatus performs minimum mean square error processing on each of the plurality of second adjusted signals and the first echo signal, to obtain a plurality of processing results, where a smaller value of the processing result indicates that a second adjusted signal corresponding to the processing result is more similar to the target spurious echo signal; and determines a second adjusted signal corresponding to a smallest value in those of the plurality of processing results as the target spurious echo signal.
It should be noted that, if an amplitude of the target spurious echo signal at a sampling moment exceeds a saturation value of the target spurious echo signal, the radar ranging apparatus may use the saturation value of the target spurious echo signal as an amplitude at the sampling moment.
Because the echo signal of the first target and the second spurious echo signal that are included in the first echo signal may be superimposed, and even an amplitude obtained after superimposition may exceed a saturation value of the first echo signal in some cases, saturation distortion is caused. In this way, the echo signal of the first target may cause interference to correction, resulting in low purity and poor accuracy of the target spurious echo signal obtained after correction.
In another possible implementation, that the radar ranging apparatus determines the target spurious echo signal based on the plurality of second adjusted signals and the first echo signal may include: The radar ranging apparatus performs minimum mean square error processing on the plurality of second adjusted signals and the first echo signal in a first sampling interval, to obtain a plurality of processing results, where a smaller value of the processing result indicates that a second adjusted signal corresponding to the processing result is more similar to the target spurious echo signal; and determines an adjusted signal corresponding to a smallest value in those of the plurality of processing results as the target spurious echo signal.
Optionally, the preset first sampling interval may be a sampling interval on the leading edge of the second spurious echo signal. If saturation exists on the second spurious echo signal, the first sampling interval does not include a sampling moment in the saturation interval.
In still another possible implementation, the radar ranging apparatus may estimate, from the first echo signal by using a Gaussian decomposition algorithm, the second spurious echo signal corresponding to the obstacle, and correct the first spurious echo signal based on the second spurious echo signal, to obtain the target spurious echo signal.
According to the radar ranging method provided in this embodiment of this application, the radar ranging apparatus estimates the second spurious echo signal from the first echo signal by using the Gaussian decomposition algorithm, and corrects the first spurious echo signal based on the second spurious echo signal. In this way, purity and accuracy of the target spurious echo signal can be improved, and therefore the accuracy of radar ranging can be improved.
In a possible implementation, the radar ranging apparatus may adjust the delay time of the first spurious echo signal a plurality of times to obtain the plurality of first adjusted signals, determine a ratio of an amplitude of the second spurious echo signal at the first sampling moment to the amplitude of each of the plurality of first adjusted signals at the first sampling moment as an amplitude coefficient of each first adjusted signal, multiply each first adjusted signal and the amplitude coefficient of each first adjusted signal to obtain a plurality of second adjusted signals, and determine the target spurious echo signal based on the plurality of second adjusted signals and the second spurious echo signal.
In a possible implementation, that the radar ranging apparatus determines the target spurious echo signal based on the plurality of second adjusted signals and the second spurious echo signal may include: The radar ranging apparatus performs minimum mean square error processing on the plurality of second adjusted signals and the second spurious echo signal, to obtain a plurality of processing results, where a smaller value of the processing result indicates that a second adjusted signal corresponding to the processing result is more similar to the target spurious echo signal; and determines a second adjusted signal corresponding to a smallest value in those of the plurality of processing results as the target spurious echo signal.
It should be noted that, for a process in which the radar ranging apparatus corrects the first spurious echo signal based on the second spurious echo signal to obtain the target spurious echo signal, refer to the process in which the radar ranging apparatus corrects the first spurious echo signal based on the first echo signal. To avoid repetition, details are not described herein again.
It should be further noted that, for a process in which the radar ranging apparatus cancels the target spurious echo signal from the first echo signal to obtain the echo signal of the first target, refer to the process in which the radar ranging apparatus cancels the spurious echo signal from the first echo signal to obtain the echo signal of the first target in the first aspect. To avoid repetition, details are not described herein again.
According to a third aspect, an embodiment of this application further provides a signal processing apparatus, configured to perform the method according to any one of the first aspect or the possible implementations of the first aspect. Specifically, the signal processing apparatus may include units configured to perform the radar ranging method according to any one of the first aspect or the possible implementations of the first aspect.
According to a fourth aspect, an embodiment of this application further provides a signal processing apparatus, including a communication interface and at least one processor. The communication interface is configured to communicate with a first transmitter and a first receiver. When the at least one processor executes program code or instructions, the radar ranging method according to any one of the first aspect or the possible implementations of the first aspect is implemented.
According to a fifth aspect, an embodiment of this application further provides a radar ranging apparatus, including the signal processing apparatus according to the fourth aspect, a first transmitter, and a first receiver. The signal processing apparatus is configured to control the first transmitter and the first receiver, to implement the radar ranging method according to any one of the first aspect or the possible implementations of the first aspect.
According to a sixth aspect, an embodiment of this application further provides a signal processing apparatus, configured to perform the method according to any one of the second aspect or the possible implementations of the second aspect. Specifically, the signal processing apparatus may include units configured to perform the radar ranging method according to any one of the second aspect or the possible implementations of the second aspect.
According to a seventh aspect, an embodiment of this application further provides a signal processing apparatus, including a communication interface and at least one processor. The communication interface is configured to communicate with a first transmitter, a first receiver, and a second receiver. When the at least one processor executes program code or instructions, the radar ranging method according to any one of the second aspect or the possible implementations of the second aspect is implemented.
According to an eighth aspect, an embodiment of this application further provides a radar ranging apparatus, including the signal processing apparatus according to the seventh aspect, a first transmitter, a first receiver, and a second receiver. The signal processing apparatus is configured to control the first transmitter, the first receiver, and the second receiver, to implement the radar ranging method according to any one of the second aspect or the possible implementations of the second aspect.
Optionally, the signal processing apparatus according to the third aspect or the sixth aspect may be a chip apparatus or an integrated circuit in a radar ranging apparatus.
According to a ninth aspect, this application further provides a computer-readable storage medium, configured to store a computer program. The computer program is used to implement the method according to any one of the foregoing aspects or the possible implementations of the foregoing aspects.
According to a tenth aspect, an embodiment of this application further provides a computer program product including instructions. When the computer program product runs on a computer, the computer is enabled to implement the method according to any one of the foregoing aspects or the possible implementations of the foregoing aspects.
According to an eleventh aspect, an embodiment of this application further provides a terminal. The terminal includes the radar ranging apparatus according to the fifth aspect or the eighth aspect. Further, the terminal may be a transportation tool or a smart device (for example, smart home or a smart manufacturing device), including an unmanned aerial vehicle, an unmanned transportation vehicle, an automobile, a robot, or the like.
The signal processing apparatus, the radar ranging apparatus, the computer storage medium, the computer program product, and the terminal provided in embodiments of this application are all configured to perform the radar ranging method provided above. Therefore, for beneficial effects that can be achieved by the signal processing apparatus, the radar ranging apparatus, the computer storage medium, the computer program product, and the terminal, refer to the beneficial effects in the radar ranging method provided above. Details are not described herein again.
The following describes technical solutions of this application with reference to accompanying drawings.
The signal processing apparatus 110 is configured to control the transmitter 120 to send a first radar signal.
Optionally, the signal processing apparatus 110 may include at least one processor. The at least one processor may implement or perform the radar ranging method provided with reference to this embodiment of this application. Alternatively, the at least one processor may be a combination of processors implementing a computing function, for example, a combination of one or more microprocessors, or a combination of digital signal processing (digital signal processing, DSP) and a microprocessor.
Optionally, there may be a plurality of types of first radar signals. This is not limited in embodiments of this application.
In a possible implementation, the first radar signal may be a millimeter-wave radar signal.
In another possible implementation, the first radar signal may be a laser radar signal, for example, an optical pulse signal.
For example, the transmitter 120 may be a laser diode (laser diode, LD).
The reflective apparatus 140 is configured to: reflect the first radar signal sent by the transmitter 120, and transmit the first radar signal out of the radar ranging apparatus 100 from a first field of view on a first plane; and/or reflect, to the receiver 131 to the receiver 13N, a first echo signal that is of the first radar signal and that is received from the first field of view. The first echo signal may include an echo signal of a first target, the echo signal of the first target is generated when the first radar signal is reflected by the first target in a vision scope of the radar ranging apparatus, and the vision scope includes the first field of view.
In a possible implementation, the first plane may be parallel to a plane formed by an x-axis and a y-axis shown in
It should be noted that, that the first plane is a horizontal plane is used as an example, and a vision scope of the radar ranging apparatus 100 on the horizontal plane determines a ranging scope of the radar ranging apparatus 100. The radar ranging apparatus 100 can perform ranging processing only on a target in the vision scope. When a field of view at which the target is located exceeds the vision scope, the radar ranging apparatus 100 cannot perform ranging processing on the target.
For example, when the vision scope of the radar ranging apparatus 100 on the horizontal plane is 120 degrees, and a horizontal angular resolution of the radar ranging apparatus 100 is 0.4 degrees, the radar ranging apparatus 100 has 120/0.4=300 horizontal field of views on the horizontal plane.
Optionally, the field of view may be an angle, or may be an angle range. This is not limited in embodiments of this application.
For example, the horizontal angular resolution of the radar ranging apparatus 100 is 0.4 degrees. In this case, the radar ranging apparatus may complete radar signal sending, echo signal receiving, and ranging processing on a target within 0.4 degrees on the horizontal plane. In other words, an angle range of 0.4 degrees may correspond to one field of view.
The signal processing apparatus 110 is further configured to: control the receiver 131 to the receiver 13N to receive the first echo signal reflected through the reflective apparatus 140; and perform ranging processing on the first target based on the first echo signal according to the radar ranging method provided in embodiments of this application.
For example, the receiver 131 to the receiver 13N may be avalanche photodiodes (avalanche photodiodes, APDs).
In a possible implementation, that the first radar signal is laser is used as an example. The signal processing apparatus 110 may measure first duration from a time point at which the radar ranging apparatus 100 sends the first radar signal to a time point at which the radar ranging apparatus 100 receives the echo signal of the first target. A product of half of the first duration (that is, duration in which the laser is transmitted by the radar ranging apparatus 100 to the first target) and a speed of light is understood as a distance between the radar ranging apparatus 100 and the first target.
In a possible implementation, the transmitter 120 and each of the receiver 131 to the receiver 13N may form one radar channel, so as to form N radar channels. The radar ranging apparatus 100 may implement radar scanning on the first plane through at least one or all of the N radar channels.
In addition, as shown in
Optionally, when the radar ranging apparatus 100 includes a plurality of signal transceiver groups, the plurality of signal transceiver groups may be disposed in a superimposition manner along the second direction.
In a possible implementation, that the radar ranging apparatus 100 includes a first radar channel, and the first radar channel includes the transmitter 120 and the receiver 131 is used as an example.
The fixed reflecting part 141 is configured to: reflect, to the rotary reflecting part 142, the first radar signal transmitted by the transmitter 120; and/or reflect, to the receiver 131 to the receiver 13N, the first echo signal reflected from the rotary reflecting part.
The rotary reflecting part 142 is configured to: transmit the first radar signal reflected by the fixed reflecting part 141 out of the window of the radar ranging apparatus 100; and/or reflect, to the fixed reflecting part 141, the first echo signal transmitted into the radar ranging apparatus 100.
In a possible implementation, the fixed reflecting part 141 may be a first plane mirror, and/or the rotary reflecting part 142 may be a second reflecting mirror.
It should be noted that a signal transmission path shown by a solid line in
Optionally, the radar ranging apparatus 100 may implement, in a plurality of manners, radar scanning on the first plane through one or more of the N radar channels. This is not limited in this embodiment of this application.
Further, as shown in
Optionally, the power apparatus 150 may be an electric machine or a motor.
In another possible implementation, that the radar ranging apparatus 100 includes a first radar channel, and the first radar channel includes the transmitter 120 and the receiver 131 is used as an example.
The power apparatus 170 is configured to drive the housing to rotate on the first plane by using the connection part 160 as a rotating shaft and based on a preset angular resolution, to implement radar scanning of the radar ranging apparatus 100 on the first plane.
In a possible implementation, the power apparatus 170 may be an electric machine or a motor.
It should be noted that the manners in which the radar ranging apparatus 100 shown in
It should be noted that
In a current technology, when a radar ranging apparatus performs ranging on a target, because a scattering phenomenon may occur in a propagation process of a radar signal sent by a transmitter, a part of scattered signals may be reflected by an inner wall, a window, a circuit, and the like inside the radar ranging apparatus, to generate a spurious echo signal, and the spurious echo signal causes interference to an echo signal of the target. In other words, a first echo signal received by a receiver corresponding to the transmitter may include both the echo signal of the target and the spurious echo signal. Consequently, if the radar ranging apparatus performs ranging on the target based on the echo signal received by the receiver, accuracy of radar ranging may be low.
Optionally, the method 200 may be performed by the radar ranging apparatus 100 shown in
S210: The radar ranging apparatus sends a first radar signal from a first field of view through a first transmitter.
In a possible implementation, the first radar signal may be an optical pulse signal.
S220: The radar ranging apparatus receives a first echo signal of the first radar signal from the first field of view through a first receiver, where the first echo signal includes an echo signal of a first target, and the first transmitter and the first receiver belong to a first radar channel.
S230: The radar ranging apparatus performs ranging processing on the first target based on the echo signal of the first target, where the first echo signal further includes a spurious echo signal, the spurious echo signal includes an echo signal generated when the first radar signal is reflected by an obstacle, at least one first signal parameter of the spurious echo signal corresponds to at least one of an identifier of the first radar channel and the first field of view, and the at least one first signal parameter includes at least one of an amplitude at at least one first sampling moment and first delay time.
Optionally, the obstacle may include an object inside the radar ranging apparatus and/or an object outside the radar ranging apparatus. This is not limited in this embodiment of this application.
In a possible implementation, the obstacle may include at least one of an inner wall, a window, or an internal circuit of the radar ranging apparatus.
In another possible implementation, the obstacle may include an object, outside the radar ranging apparatus, other than the first target.
The following describes S230 in two cases.
Case 1: The radar ranging apparatus includes only the first radar channel. In other words, the spurious echo signal includes the echo signal generated when the first radar signal is reflected by the obstacle.
Correspondingly, S230 may include: The radar ranging apparatus determines the at least one first signal parameter of the spurious echo signal based on at least one of the identifier of the first radar channel and the first field of view, determines the spurious echo signal based on the at least one first signal parameter, cancels the spurious echo signal from the first echo signal to obtain the echo signal of the first target, and performs ranging processing on the first target based on the echo signal of the first target.
Optionally, the radar ranging apparatus may determine the at least one first signal parameter in a plurality of manners based on at least one of the identifier of the first radar channel and the first field of view. This is not limited in this embodiment of this application.
In a possible implementation, the at least one first signal parameter may correspond to only the first field of view, in other words, the first field of view and the at least one first signal parameter may meet a predefined first mapping relationship.
Correspondingly, the radar ranging apparatus may determine the at least one first signal parameter based on the first field of view and the first mapping relationship.
In another possible implementation, the at least one first signal parameter may correspond to the first field of view and the identifier of the first radar channel, in other words, the first field of view, the identifier of the first radar channel, and the at least one first signal parameter may meet the predefined first mapping relationship.
It should be noted that the at least one first signal parameter may include at least one of the amplitude at the at least one first sampling moment and the first delay time. The at least one first sampling moment may be understood as at least one sampling moment of the spurious echo signal, and the first delay time may be understood as a time difference from transmitting the first radar signal to receiving the spurious echo signal.
For example, the first radar signal may be shown in (a) in
In a possible implementation, when the at least one first signal parameter includes an amplitude at one first sampling moment, the radar ranging apparatus may determine the spurious echo signal based on the amplitude at the first sampling moment and preset waveform information of the spurious echo signal, where the waveform information indicates a waveform of the spurious echo signal.
For example, the waveform information is a schematic diagram of a waveform shown in
In another possible implementation, when a quantity of the at least one first signal parameter is greater than 1, and the at least one first signal parameter includes amplitudes at a plurality of first sampling moments, the radar ranging apparatus may perform difference processing on the amplitudes at the plurality of first sampling moments by using a difference algorithm, to determine the spurious echo signal.
For example, the at least one first signal parameter includes an amplitude A1 of a leading edge of a spurious echo signal shown in
Optionally, that the first field of view, the identifier of the first radar channel, and the at least one first signal parameter meet the predefined first mapping relationship is used as an example. Before S230, the radar ranging apparatus may obtain at least one mapping relationship. The at least one mapping relationship includes the first mapping relationship, and the at least one mapping relationship indicates a correspondence between an identifier of a radar channel, a field of view, and a first signal parameter.
Correspondingly, in S230, the radar ranging apparatus may obtain, based on the at least one mapping relationship, the at least one first signal parameter corresponding to the identifier of the first radar channel and the first field of view.
Optionally, the radar ranging apparatus may obtain the at least one mapping relationship in a plurality of manners. This is not limited in this embodiment of this application.
In a possible implementation, the radar ranging apparatus may preconfigure the at least one mapping relationship.
In another possible implementation, the radar ranging apparatus may receive the at least one mapping relationship from another apparatus in advance.
In still another possible implementation, the radar ranging apparatus may generate the at least one mapping relationship.
Optionally, the at least one mapping relationship may be represented in a plurality of forms. This is not limited in this embodiment of this application.
For example, the at least one mapping relationship may be represented by a mapping table 1 shown in the following Table 1.
For example, the identifier of the first radar channel is 001, and the first field of view is 14.5 degrees.
It should be noted that, that the echo signal of the first target and the spurious echo signal in the first echo signal in
According to the radar ranging method provided in this embodiment of this application, the at least one statically set mapping relationship is queried based on at least one of the identifier of the first radar channel and the first field of view, the at least one first signal parameter corresponding to the first radar channel and/or the first field of view is obtained based on the at least one mapping relationship, the spurious echo signal is determined based on the at least one first signal parameter, the spurious echo signal is canceled from the first echo signal to obtain the echo signal of the first target, and the ranging processing is performed on the first target based on the echo signal of the first target. In this way, interference and impact of the spurious echo signal on the echo signal of the first target can be avoided, in other words, purity of the echo signal of the first target can be improved, and therefore accuracy of radar ranging can be improved.
It should be noted that, because the amplitude at the first sampling moment and/or the first delay time may change with an operating temperature of the radar ranging apparatus, the at least one first signal parameter may represent a signal parameter at a first operating temperature, in other words, at least one of the identifier of the first radar channel and the first field of view, the first operating temperature, and the at least one first signal parameter may meet a predefined first mapping relationship.
Correspondingly, S230 may include: The radar ranging apparatus determines the at least one first signal parameter based on the first operating temperature and at least one of the identifier of the first radar channel and the first field of view.
For example, the at least one mapping relationship may alternatively be represented by a mapping table 2 shown in the following Table 2.
It should be noted that a signal parameter corresponding to an operating temperature that is not shown in Table 2 may be obtained through calculation based on signal parameters corresponding to existing operating temperatures. This is not limited in this embodiment of this application.
For example, the identifier of the first radar channel is 001, and the first field of view is 14.5°. The radar ranging apparatus may determine, based on the delay time 100 ns corresponding to the operating temperature −10° C. and the delay time 100.3 ns corresponding to the operating temperature −9° C. that are shown in Table 2, that delay time corresponding to an operating temperature −9.5° C. is (100+100.3)/2=100.15 ns.
It should be further noted that, because the mapping table 2 needs to include a first signal parameter at each operating temperature, and therefore the radar ranging apparatus needs to store a large amount of data, it may be considered that only a first signal parameter at a standard operating temperature is stored, and a variation value of a first signal parameter at another operating temperature compared with the first signal parameter at the standard operating temperature is incrementally stored, so that an amount of stored data can be reduced.
For another example, the mapping table 2 shown in Table 2 may alternatively be represented by a mapping table 3 shown in the following Table 3.
For example, the identifier of the first radar channel is 001, the first field of view is 14.5°, and the first operating temperature is −9° C. The radar ranging apparatus may look up the mapping table 3 shown in Table 3 by using the identifier 001, the first field of view 14.5°, and the first operating temperature −9° C., to obtain the amplitude 99 at the sampling moment t1 at the standard temperature, the amplitude 121 at the sampling moment t2 at the standard temperature, the amplitude 87 at the sampling moment t3 at the standard temperature, the delay time 100 ns at the standard temperature, the amplitude coefficient 0.95, and the delay time difference +0.3 ns. The amplitude coefficient indicates a ratio of an amplitude at a sampling moment at the first operating temperature to an amplitude at the sampling moment at the standard operating temperature. The delay time difference indicates a time difference between delay time at the first operating temperature and delay time at the standard temperature.
Correspondingly, the radar ranging apparatus may multiply the amplitude coefficient 0.95 and each of the amplitude 99 at the sampling moment t1 at the standard temperature, the amplitude 121 at the sampling moment t2 at the standard temperature, and the amplitude 87 at the sampling moment t3 at the standard temperature, to obtain an amplitude 94.05 at the sampling moment t1 at the first operating temperature −9° C., an amplitude 114.95 at the sampling moment t2 at the first operating temperature −9° C., and an amplitude 82.62 at the sampling moment t3 at the first operating temperature −9° C. In addition, the radar ranging apparatus adds the delay time 100 ns at the standard temperature and the delay time difference 0.3 ns, to obtain delay time 100.3 ns at the first operating temperature −9° C.
According to the radar ranging method provided in this embodiment of this application, the at least one statically set mapping relationship is queried based on the current first operating temperature and at least one of the identifier of the first radar channel and the first field of view, the at least one first signal parameter corresponding to the first operating temperature and the identifier of the first radar channel and/or the first field of view is obtained based on the at least one mapping relationship, the spurious echo signal is determined based on the at least one first signal parameter, the spurious echo signal is canceled from the first echo signal to obtain the echo signal of the first target, and the ranging processing is performed on the first target based on the echo signal of the first target. In this way, the interference and the impact of the spurious echo signal on the echo signal of the first target can be avoided, and therefore the accuracy of radar ranging can be improved.
Optionally, in S230, the radar ranging apparatus may cancel the spurious echo signal from the first echo signal in a plurality of manners, to obtain the echo signal of the first target. This is not limited in this embodiment of this application.
In a possible implementation, that the spurious echo signal includes P sampling moments, the P sampling moments correspond to P first amplitudes on the spurious echo signal, the first echo signal includes the P sampling moments and Q sampling moments, the P sampling moments correspond to P second amplitudes on the first echo signal, the Q sampling moments correspond to Q third amplitudes on the first echo signal, and both P and Q are integers greater than 0 is used as an example. The echo signal of the first target may include the P sampling moments and the Q sampling moments. The P sampling moments correspond to P target amplitudes on the echo signal of the first target, and a target amplitude corresponding to each of the P sampling moments is a difference between a first amplitude and a second amplitude. The Q sampling moments correspond to the Q third amplitudes on the echo signal of the first target.
An example is provided below: The spurious echo signal includes three sampling moments, for example, a sampling moment t1 to a sampling moment t3, where a first amplitude corresponding to the sampling moment t1 is 110.3 (where a unit is omitted), a first amplitude corresponding to a sampling moment t2 is 116, and a first amplitude corresponding to the sampling moment t3 is 114.7. The first echo signal includes six sampling moments, for example, the sampling moment t1 to a sampling moment t6, where a second amplitude corresponding to the sampling moment t1 is 109.1, a second amplitude corresponding to the sampling moment t2 is 116, a second amplitude corresponding to the sampling moment t3 is 112.4, a third amplitude corresponding to a sampling moment t4 is 125.6, a third amplitude corresponding to a sampling moment t5 is 120.6, and a third amplitude corresponding to the sampling moment t6 is 118.9. In this case, the spurious echo signal includes the sampling moment t1 to the sampling moment t6, where a target amplitude corresponding to the sampling moment t1 is 110.3−109.1=1.2, a target amplitude corresponding to the sampling moment t2 is 116−116=0, a target amplitude corresponding to the sampling moment t3 is 114.7-112.4=2.3, a target amplitude corresponding to the sampling moment t4 is 125.6, a target amplitude corresponding to the sampling moment t5 is 120.6, and a target amplitude corresponding to the sampling moment t6 is 118.9.
It should be noted that, because target amplitudes corresponding to the sampling moment t1 to the sampling moment t3 are less than or equal to a preset jitter threshold 5, the target amplitudes corresponding to the sampling moment t1 to the sampling moment t3 may be filtered out in a denoising processing process. Therefore, the echo signal of the first target may include only target amplitudes corresponding to the sampling moment t4 to the sampling moment t6.
Case 2: The radar ranging apparatus includes a plurality of radar channels, and at least two of the plurality of radar channels belong to different signal transceiver groups.
Optionally, that the at least two radar channels include the first radar channel and a second radar channel, and the second radar channel includes a second transmitter is used as an example. Before S230, the method 200 may further include: The radar ranging apparatus sends a second radar signal from a second field of view through the second transmitter.
In other words, the spurious echo signal includes a first spurious echo signal generated when the first radar signal is reflected by the obstacle and a second spurious echo signal generated when the second radar signal is reflected by the obstacle.
Correspondingly, S230 may include: The radar ranging apparatus determines at least one first signal parameter of the first spurious echo signal based on at least one of the identifier of the first radar channel and the first field of view, determines the first spurious echo signal based on the at least one first signal parameter, determines at least one second signal parameter of the second spurious echo signal based on at least one of an identifier of the second radar channel and the second field of view, determines the second spurious echo signal based on the at least one second signal parameter, cancels the first spurious echo signal and the second spurious echo signal from the first echo signal to obtain the echo signal of the first target, and performs ranging processing on the first target based on the echo signal of the first target.
Optionally, the first field of view and the second field of view may be the same, or may be different. This is not limited in this embodiment of this application.
It should be noted that, for a process in which the radar ranging apparatus determines the at least one second signal parameter of the second spurious echo signal based on at least one of the identifier of the second radar channel and the second field of view, refer to the process in which the radar ranging apparatus determines the at least one first signal parameter of the spurious echo signal based on at least one of the identifier of the first radar channel and the first field of view in the case 1. To avoid repetition, details are not described herein again.
It should be further noted that, for a process in which the radar ranging apparatus cancels the first spurious echo signal and the second spurious echo signal from the first echo signal to obtain the echo signal of the first target, refer to the process in which the radar ranging apparatus cancels the spurious echo signal from the first echo signal to obtain the echo signal of the first target in the case 1.
The foregoing describes, with reference to
Optionally, the method 300 may be performed by the radar ranging apparatus 100 shown in
S310: The radar ranging apparatus sends a first radar signal through a first transmitter.
S320: The radar ranging apparatus receives a first echo signal of the first radar signal through a first receiver, where the first echo signal includes an echo signal of a first target.
S330: The radar ranging apparatus receives a second echo signal of the first radar signal through a second receiver, where the second receiver is located outside a primary signal transmission path between the first transmitter and the first receiver.
In other words, the primary signal transmission path between the first transmitter and the first receiver includes the first target, and therefore the first echo signal received by the first receiver includes the echo signal of the first target. In addition, the second receiver is located outside the primary signal transmission path, and therefore the second echo signal received by the second receiver does not include the echo signal of the first target.
Optionally, the radar ranging apparatus may include a first signal transceiver group and a second signal transceiver group. The first signal transceiver group includes the first transmitter and the first receiver. The second signal transceiver group includes the second receiver and a second transmitter, and the radar ranging apparatus does not send a radar signal through the second transmitter. Alternatively, the second receiver may be a receiver additionally disposed outside the primary signal transmission path between the first transmitter and the first receiver. This is not limited in this embodiment of this application.
For example, as shown in
For example, the first transmitter may be an LD, the first receiver may be an APD, and the second receiver may be a photodiode (positive intrinsic-negative, PIN).
S340: The radar ranging apparatus performs ranging processing on the first target based on the first echo signal and the second echo signal, where the second echo signal is used to determine a target spurious echo signal corresponding to an obstacle, and the echo signal of the first target does not include the target spurious echo signal.
Optionally, the obstacle may include an object inside the radar ranging apparatus and/or an object outside the radar ranging apparatus. This is not limited in this embodiment of this application.
In a possible implementation, the obstacle may include at least one of an inner wall of a housing, a window, or an internal circuit of the radar ranging apparatus.
In another possible implementation, the obstacle may further include an object, outside the radar ranging apparatus, other than the first target.
Optionally, S340 may include: The radar ranging apparatus determines the target spurious echo signal corresponding to the obstacle based on the second echo signal, cancels the target spurious echo signal from the first echo signal to obtain the echo signal of the first target, and performs ranging processing on the first target based on the echo signal of the first target.
It should be noted that, as shown in
However, because the first receiver and the second receiver are located at different locations, delay time and/or amplitudes of the first spurious echo signal and the second spurious echo signal may be different. Therefore, when the first spurious echo signal is directly used to cancel the second spurious echo signal from the first echo signal, incomplete cancellation (in other words, purity of the echo signal of the first target that is obtained after cancellation is low) or excessive cancellation (in other words, a part of the echo signal of the first target that is obtained after cancellation is missing) may exist, resulting in poor accuracy of radar ranging performed based on the echo signal of the first target.
Optionally, the radar ranging apparatus may determine, based on the first spurious echo signal, the target spurious echo signal corresponding to the obstacle, where the target spurious echo signal may be considered to be the most similar to the target spurious echo signal in the first echo signal; and cancel the target spurious echo signal from the first echo signal to obtain the echo signal of the first target.
In a possible implementation, the radar ranging apparatus may correct the first spurious echo signal based on the first echo signal, to obtain the target spurious echo signal.
Optionally, the radar ranging apparatus may correct the first spurious echo signal based on the first echo signal in a plurality of manners, to obtain the target spurious echo signal. This is not limited in this embodiment of this application.
In a possible implementation, the radar ranging apparatus may adjust delay time of the first spurious echo signal a plurality of times to obtain a plurality of first adjusted signals, determine a ratio of an amplitude of the first echo signal at a first sampling moment to an amplitude of each of the plurality of first adjusted signals at the first sampling moment as an amplitude coefficient of each first adjusted signal, multiply each first adjusted signal and the amplitude coefficient of each first adjusted signal to obtain a plurality of second adjusted signals, and determine the target spurious echo signal based on the plurality of second adjusted signals and the first echo signal.
Optionally, when the second spurious echo signal in the first echo signal and a first target echo signal are not superimposed, the first sampling moment may be any sampling moment on the second spurious echo signal. Alternatively, when the second spurious echo signal in the first echo signal and a first target echo signal are superimposed, the first sampling moment may be a sampling moment corresponding to a peak of the second spurious echo signal or a sampling moment on a leading edge of the second spurious echo signal. Alternatively, when saturation exists on the second spurious echo signal, the first sampling moment may be a sampling moment on a leading edge of the second spurious echo signal except a saturation interval.
For example, the first echo signal is shown in
For another example, the first echo signal is shown in
For another example, the first echo signal is shown in
In a possible implementation, that the radar ranging apparatus determines the target spurious echo signal based on the plurality of second adjusted signals and the first echo signal may include: The radar ranging apparatus performs minimum mean square error processing on each of the plurality of second adjusted signals and the first echo signal, to obtain a plurality of processing results, where a smaller value of the processing result indicates that a second adjusted signal corresponding to the processing result is more similar to the target spurious echo signal; and determines a second adjusted signal corresponding to a smallest value in those of the plurality of processing results as the target spurious echo signal.
For example,
For example, the first echo signal is s(t), and the first spurious echo signal is f(t). The radar ranging apparatus may adjust the delay time of the first spurious echo signal a plurality of times based on a preset delay time difference Δt, to obtain a plurality of first adjusted signals, for example, f(t−2Δt), f(t−Δt), f(t), and f(t+Δt) shown in (d) in
It should be noted that, if an amplitude of the target spurious echo signal K2f(t−Δt) at a sampling moment exceeds a saturation value of the target spurious echo signal, the radar ranging apparatus may use the saturation value of the target spurious echo signal as an amplitude at the sampling moment.
For example,
According to the radar ranging method provided in this embodiment of this application, the radar ranging apparatus can cancel, based on the second spurious echo signal received in real time, the target spurious echo signal corresponding to the obstacle from the first echo signal, so that interference caused by the spurious echo signal to the echo signal of the first target can be reduced, in other words, purity of the echo signal of the first target can be improved, and therefore accuracy of radar ranging can be improved.
Because the echo signal of the first target and the second spurious echo signal that are included in the first echo signal may be superimposed, and even an amplitude obtained after superimposition may exceed a saturation value of the first echo signal in some cases, saturation distortion is caused (as shown in
In another possible implementation, that the radar ranging apparatus determines the target spurious echo signal based on the plurality of second adjusted signals and the first echo signal may include: The radar ranging apparatus performs minimum mean square error processing on the plurality of second adjusted signals and the first echo signal in a first sampling interval, to obtain a plurality of processing results, where a smaller value of the processing result indicates that a second adjusted signal corresponding to the processing result is more similar to the target spurious echo signal; and determines an adjusted signal corresponding to a smallest value in those of the plurality of processing results as the target spurious echo signal.
Optionally, the preset first sampling interval may be a sampling interval on the leading edge of the second spurious echo signal. If saturation exists on the second spurious echo signal, the first sampling interval does not include a sampling moment in the saturation interval.
For example, as shown in
For another example, as shown in
In still another possible implementation, the radar ranging apparatus may estimate, from the first echo signal by using a Gaussian decomposition algorithm, the second spurious echo signal corresponding to the obstacle, and correct the first spurious echo signal based on the second spurious echo signal, to obtain the target spurious echo signal.
According to the radar ranging method provided in this embodiment of this application, the radar ranging apparatus estimates the second spurious echo signal from the first echo signal by using the Gaussian decomposition algorithm, and corrects the first spurious echo signal based on the second spurious echo signal. In this way, purity and accuracy of the target spurious echo signal can be improved, and therefore accuracy of radar ranging can be improved.
In a possible implementation, the radar ranging apparatus may adjust the delay time of the first spurious echo signal a plurality of times to obtain the plurality of first adjusted signals, determine a ratio of an amplitude of the second spurious echo signal at the first sampling moment to the amplitude of each of the plurality of first adjusted signals at the first sampling moment as an amplitude coefficient of each first adjusted signal, multiply each first adjusted signal and the amplitude coefficient of each first adjusted signal to obtain a plurality of second adjusted signals, and determine the target spurious echo signal based on the plurality of second adjusted signals and the second spurious echo signal.
In a possible implementation, that the radar ranging apparatus determines the target spurious echo signal based on the plurality of second adjusted signals and the second spurious echo signal may include: The radar ranging apparatus performs minimum mean square error processing on the plurality of second adjusted signals and the second spurious echo signal, to obtain a plurality of processing results, where a smaller value of the processing result indicates that a second adjusted signal corresponding to the processing result is more similar to the target spurious echo signal; and determines a second adjusted signal corresponding to a smallest value in those of the plurality of processing results as the target spurious echo signal.
It should be noted that, for a process in which the radar ranging apparatus corrects the first spurious echo signal based on the second spurious echo signal to obtain the target spurious echo signal, refer to the process shown in
It should be further noted that, for a process in S340 in which the radar ranging apparatus cancels the target spurious echo signal from the first echo signal to obtain the echo signal of the first target, refer to the process in which the radar ranging apparatus cancels the spurious echo signal from the first echo signal to obtain the echo signal of the first target in S230 in the embodiment of the method 200. To avoid repetition, details are not described herein again.
The foregoing describes, with reference to
It should be noted that the signal processing apparatus 400 may be the signal processing apparatus in the foregoing method embodiments. This is not limited in this embodiment of this application.
It may be understood that, to implement the foregoing functions, the signal processing apparatus 400 includes corresponding hardware and/or software modules for performing the functions. With reference to the example algorithm steps described in the embodiments disclosed in this specification, embodiments of this application can be implemented in a form of hardware or a combination of hardware and computer software. Whether a function is performed by hardware or hardware driven by computer software depends on particular applications and design constraints of the technical solutions. A person skilled in the art may use different methods to implement the described functions for each particular application with reference to embodiments, but it should not be considered that the implementation goes beyond the scope of this application.
In embodiments of this application, the signal processing apparatus 400 may be divided into functional modules based on the foregoing method examples. For example, each functional module may be obtained through division based on each corresponding function, or two or more functions may be integrated into one processing module. The integrated module may be implemented in a form of hardware. It should be noted that, in embodiments of this application, division into the modules is an example and is merely logical function division, and may be other division during actual implementation.
When each functional module is obtained through division based on each corresponding function,
It should be noted that the transceiver unit 410 is obtained through functional division of the transceiver (including each transmitter and/or each receiver) in the foregoing embodiments.
It should be noted that, all related content of the steps in the foregoing method embodiments may be cited in function descriptions of corresponding functional modules. Details are not described herein again.
The signal processing apparatus 400 provided in this embodiment is configured to perform the foregoing method embodiments, and therefore can achieve same effects as the foregoing implementation methods.
When an integrated unit is used, the signal processing apparatus 400 may include a processing unit, a storage unit, and a communication unit. The processing unit may be configured to control and manage an action of the signal processing apparatus 400, for example, may be configured to support the signal processing apparatus 400 in performing the steps performed by the foregoing units. The storage unit may be configured to support the signal processing apparatus 400 in storing program code, data, and the like. The communication unit may be configured to support the signal processing apparatus 400 in communicating with another device.
The processing unit may be a processor or a controller. The processing unit may implement or execute various example logical blocks, modules, and circuits described with reference to content disclosed in this application. Alternatively, the processor may be a combination of processors implementing a computing function, for example, a combination of one or more microprocessors, or a combination of digital signal processing (digital signal processing, DSP) and a microprocessor. The storage unit may be a memory. The communication unit may be specifically a device, for example, a radio frequency circuit, a Bluetooth chip, or a Wi-Fi chip, that communicates with another electronic device.
Optionally, the signal processing apparatus 400 may be a chip or a system on chip in the radar ranging apparatus in the foregoing embodiments.
An embodiment of this application further provides a computer storage medium. The computer storage medium stores computer instructions. When the computer instructions are run on an electronic device, the electronic device is enabled to perform the related method steps, to implement the radar ranging method in the foregoing embodiments.
An embodiment of this application further provides a computer program product. When the computer program product runs on a computer, the computer is enabled to perform the related steps, to implement the radar ranging method in the foregoing embodiments.
The signal processing apparatus, the radar ranging apparatus, the computer storage medium, the computer program product, and the chip provided in embodiments are all configured to perform the corresponding method provided above. Therefore, for beneficial effects that can be achieved by the signal processing apparatus, the radar ranging apparatus, the computer storage medium, the computer program product, or the chip, refer to the beneficial effects in the corresponding method provided above. Details are not described herein again.
It should be understood that sequence numbers of the foregoing processes do not mean execution sequences in embodiments of this application. The execution sequences of the processes should be determined based on functions and internal logic of the processes, and should not constitute any limitation on implementation processes of embodiments of this application.
A person of ordinary skill in the art may be aware that, in combination with the examples described in embodiments disclosed in this specification, units and algorithm steps can be implemented by electronic hardware or a combination of computer software and electronic hardware. Whether the functions are performed by hardware or software depends on particular applications and design constraints of the technical solutions. A person skilled in the art may use different methods to implement the described functions for each particular application, but it should not be considered that the implementation goes beyond the scope of this application.
It may be clearly understood by a person skilled in the art that, for the purpose of convenient and brief description, for a detailed working process of the foregoing system, apparatus, and unit, refer to a corresponding process in the foregoing method embodiments. Details are not described herein again.
In several embodiments provided in this application, it should be understood that the disclosed system, apparatus, and method may be implemented in other manners. For example, the described apparatus embodiment is merely an example. For example, division into the units is merely logical function division and may be other division during actual implementation. For example, a plurality of units or components may be combined or integrated into another system, or some features may be ignored or not performed. In addition, the displayed or discussed mutual couplings or direct couplings or communication connections may be implemented through some interfaces. The indirect couplings or communication connections between the apparatuses or units may be implemented in electrical, mechanical, or other forms.
The units described as separate parts may or may not be physically separate, and parts displayed as units may or may not be physical units, that is, may be located in one position, or may be distributed on a plurality of network units. Some or all of the units may be selected based on actual requirements to achieve the objectives of the solutions of embodiments.
In addition, functional units in embodiments of this application may be integrated into one processing unit, each of the units may exist alone physically, or two or more units may be integrated into one unit.
When the functions are implemented in a form of a software functional unit and sold or used as an independent product, the functions may be stored in a computer-readable storage medium. Based on such an understanding, the technical solutions of this application essentially, or the part contributing to the current technology, or some of the technical solutions may be implemented in a form of a software product. The computer software product is stored in a storage medium, and includes several instructions for instructing a computer device (which may be a personal computer, a server, or a network device) to perform all or some of the steps of the methods described in embodiments of this application. The foregoing storage medium includes any medium that can store program code, such as a USB flash drive, a removable hard disk, a read-only memory (Read-Only Memory, ROM), a random access memory (Random Access Memory, RAM), a magnetic disk, or a compact disc.
The foregoing descriptions are merely specific implementations of this application, but are not intended to limit the protection scope of this application. Any variation or replacement readily figured out by a person skilled in the art within the technical scope disclosed in this application shall fall within the protection scope of this application. Therefore, the protection scope of this application shall be subject to the protection scope of the claims.
This application is a continuation of International Application No. PCT/CN2020/118402, filed on Sep. 28, 2020, the disclosure of which is hereby incorporated by reference in its entirety.
| Number | Date | Country | |
|---|---|---|---|
| Parent | PCT/CN2020/118402 | Sep 2020 | US |
| Child | 18191526 | US |
