Patent Application
20190036623
The present disclosure relates to an apparatus for determination of a time delay attributable to an antenna and its associated antenna circuitry. It also relates to an associated method and a device including said apparatus.
According to a first aspect of the present disclosure there is provided an apparatus comprising:
In one or more embodiments, the second antenna comprises one or more of:
In one or more embodiments, the apparatus includes a switch arrangement configured to provide one or both of:
In one or more embodiments, the apparatus is configured to provide a calibration mode and a normal-operation mode;
In one or more embodiments, the apparatus is configured to provide a calibration mode and a normal-operation mode and, in the calibration mode, the calibration device is configured to determine the time delay and, in the normal-operation mode, the apparatus is configured to perform time-of-flight determination of signals sent between the apparatus and at least one remote device using, in part, the time delay determined by the calibration device.
In one or more embodiments, the transceiver of the apparatus comprises an ultra-wide band transceiver.
In one or more embodiments, the calibration device is configured to determine the time delay at one or more of the following times:
In one or more embodiments, the calibration device is configured to determine a cross-correlation function based on cross-correlation of the signal sent from one of the first and second antenna and the signal received via the other of the first and second antenna, the time delay based on identification of a peak in the cross-correlation function subsequent to an initial peak.
In one or more embodiments, the time delay comprises a time delay introduced by at least the first antenna, said antenna circuitry and analogue signal processing components of the apparatus.
According to a second aspect of the present disclosure there is provided a method of calibrating an apparatus to account for a time delay introduced by at least a first antenna and antenna circuitry of said first antenna, wherein the apparatus includes a transceiver, said first antenna connected to the transceiver via said antenna circuitry configured to provide for one or more of impedance matching and filtering; a second antenna connected to the transceiver bypassing said antenna circuitry, the method comprising:
In one or more embodiments, determining said time delay includes performing cross-correlation on the signal sent by the transceiver and the signal received by the transceiver.
In one or more embodiments, the method includes a step, prior to said determining step, of switching to a calibration mode in which a transmitter element of the transceiver is configured to send said signal from one of the first and second antennas and a receiver element is configured to receive said signal sent by the transmitter element from the other of the first and second antennas.
In one or more embodiments, switching to said calibration mode comprises switching from a normal-operation mode in which the transceiver is configured to both send and receive signals via the first antenna.
In one or more embodiments, the method includes the step of providing for sending of a ranging signal from the first antenna and receiving a signal from a remote device sent in response to said ranging signal, the apparatus configured to determine a time of flight of said ranging signal and the response thereto using, in part, the determined time delay.
According to a third aspect of the present disclosure there is provided a device including the apparatus of the first aspect, the device comprising one of an automotive key fob, a vehicle comprising an access control system of which the apparatus forms part and an access control system.
While the disclosure is amenable to various modifications and alternative forms, specifics thereof have been shown by way of example in the drawings and will be described in detail.
It should be understood, however, that other embodiments, beyond the particular embodiments described, are possible as well. All modifications, equivalents, and alternative embodiments falling within the spirit and scope of the appended claims are covered as well.
The above discussion is not intended to represent every example embodiment or every implementation within the scope of the current or future Claim sets. The figures and
Detailed Description that follow also exemplify various example embodiments. Various example embodiments may be more completely understood in consideration of the following Detailed Description in connection with the accompanying Drawings.
One or more embodiments will now be described by way of example only with reference to the accompanying drawings in which:
With reference to
The time of flight of the signal between the first device 101 and the second device 102 may be used to yield the distance between the devices 101, 102. The accuracy of the time of flight may be important for accurate determination of the distance between the devices 101, 102, termed “ranging”. The time measured by timer 106 may comprise a function of the actual time of flight, the processing delay at the second device 102 measured by timer 110, a processing delay at the first device 101 and a delay introduced by the antennas 104, 108 and their associated circuitry.
The processing delays may be measured by circuitry (not shown) or otherwise determined and can thus be accounted for. However, the delay introduced by the antennas and their circuitry may be more difficult to account for. Further, the antenna delay may vary in use or from device to device due to manufacturing differences or factors such as age and temperature.
The second antenna 203 is connected to the transceiver 201 but does not connect via the antenna circuitry 204. In one or more examples, the connection between the second antenna 203 and the transceiver is absent of an impedance matching network. In one or more examples, the connection between the second antenna 203 and the transceiver is absent of circuitry to provide for filtering of a signal.
The apparatus 200 includes a calibration device 205 configured to determine a time delay introduced by at least the first antenna 202 and said antenna circuitry 204 based on at least one of:
The first antenna 202 may comprise the default antenna of the apparatus 200 used when the calibration device is not determining the time delay. Thus, during a normal-operation mode the first antenna 202 may be used by the transceiver 201 and the second antenna may not be used, while during a calibration mode both the first and second antennas 202, 203 may be used by the calibration device 205.
The first antenna 202 may be selected from a traveling wave antenna, a monocone antenna, a bowtie antenna, a Vivaldi antenna, a printed monopole antenna or a horn antenna.
The second antenna 203 may only be used for calibration. Accordingly, the second antenna 203 may be of a different type, size or shape in comparison to the first antenna 202. Further, as the second antenna 203 may only be used to receive a signal from the first antenna 202 (which is also part of the apparatus and therefore close by) or send a signal for receipt by the first antenna 202, it does not need to have a high gain nor is it required to be particularly efficient.
In one or more examples, and as shown in
In one or more examples, the second antenna 203 may comprise solely an integrated circuit package terminal (not shown) of the integrated circuit package 402 (i.e. without the metal trace 400). At 4-9 GHz it is known for conductive parts of the circuit to act as an antenna and radiate a signal. This may be exploited and rather than provide a dedicated conductive structure to act as an antenna, a terminal, pin or leg of the integrated circuit package 402 may provide the second antenna 203.
In general, the second antenna 203 may be considered to be a “parasitic antenna” of the apparatus 200 such that a part of the apparatus 200 not specifically designed to be an antenna may comprise the second antenna 203.
Turning back to
The transmitter element 206 and the receiver element 207 may receive signals from a digital baseband processing element 210, which may provide for digital processing of the signals to be sent and the signals received via the antennas 202, 203 as appropriate.
In this example, the calibration device 205 is shown as part of the digital baseband processing element 210 and it thus operates in the digital domain. However, in other examples, the calibration device 205 may be separate from the digital baseband processing element 210 and may operate in the analogue, digital or mixed signal domains.
The switch arrangement 211 provides for control of a connection to the receiver element 207 of the apparatus that is switchable to connect it to the first antenna 202 or to the second antenna 203.
Thus, in this example, during the calibration mode, the switch arrangement 211 is configured to connect the receiver element 207 to the second antenna 203 and, during the normal-operation mode, the switch arrangement 211 is configured to connect the receiver element 207 to the first antenna 202.
In the calibration mode, the calibration device 205 may provide for sending of a signal, termed here a calibration signal, by the transmitter element 206 using the first antenna 202. Accordingly, the calibration signal will include a time delay introduced by at least the antenna circuitry 204. The calibration signal is received by the receiver element 207 via the second antenna 203, as the switch arrangement 211 connects the receiver element 207 thereto.
The time delay introduced by the antenna 202 and antenna circuitry may then be determined based on the time between sending and receiving the calibration signal. The position of the first antenna 202 relative to the second antenna 203 is, in this example, fixed. Thus, the propagation time of the calibration signal time through space can be deducted leaving the time delay may be due to operation of the antenna circuitry subject to any other known time delays. The determined time delay may then be accounted for when performing time of flight determination in the normal-operation mode.
In this example, the receiver element 207 is configured to always receive signals using the first antenna 202. Accordingly, in the normal-operation mode, signals received from one or more remote devices will be received by the receiver element 207 via the first antenna 202 and not the second antenna 203. Further, in the calibration mode for this example, any signals received for the purpose of calibration will also be received via the first antenna 202.
The switch arrangement 311 provides for control of a connection from the transmitter element 206 of the apparatus that is switchable to connect it to the first antenna 202 or to the second antenna 203.
Thus, in this example, during the calibration mode, the switch arrangement 311 is configured to connect the transmitter element 206 to the second antenna 203 and, during the normal-operation mode, the switch arrangement 311 is configured to connect the transmitter element 206 to the first antenna 202.
In the calibration mode, the calibration device 205 may provide for sending of a signal, termed here a calibration signal, by the transmitter element 206 using the second antenna 203. The calibration signal is received by the receiver element 207 via the first antenna 202. Accordingly, the signal will include a delay introduced by at least the antenna circuitry 204 when received by the first antenna 202.
The time delay introduced by the antenna 202 and antenna circuitry may, as before, then be determined based on the time between sending and receiving the calibration signal.
The position of the first antenna 202 relative to the second antenna 203 is, in this example as in the previous example, fixed.
The apparatus 200, 300 may be configured to determine the time delay at various times. For example, the apparatus 200, 300 may enter the calibration mode and the calibration device 205 may be configured to determine the time delay at start-up of the apparatus 200, 300. Accordingly, in response to power being provided to the apparatus, the calibration device 205 may be configured to determine the time delay. In other examples, the calibration device 205 may be configured to determine the time delay periodically or according to a predefined schedule. In one or more examples, the need to perform ranging may provide a prompt for the calibration device to determine the time delay. Accordingly, in response to a user actuation or in response to receipt of a signal from a remote device, the calibration device may, prior to sending and/or receiving a message for use in time of flight determination, provide for sending of a calibration signal between the first and second antennas 202, 203 for determination of the time delay. The time delay may then be accounted for in time of flight determination.
The calibration device 205 may use any desirable method to determine the time delay introduced by the antenna 202 and the antenna circuitry 204. For example, the calibration device may determine time between sending of the calibration signal via one of the first and second antennas and the receipt of the calibration signal via the other of the first and second antennas 202, 203 to be a function where;
Time between sending and receiving the calibration signal=time of flight between antennas+processing delay of transmitter element 206+processing delay of receiver element 207+“time delay of at least the antenna circuitry”.
The distance between the first and second antennas may be known and therefore the time of flight between antennas may also be known. The processing delay of the transmitter element 206 and receiver element 207 may be known or determined by other means.
In one or more examples, the time delay of at least the antenna circuitry may include the processing delay of the transmitter element 206 and receiver element 207. Accordingly, the calibration device 205, in some examples may determine the time delay introduced by the antenna circuitry and the analogue/mixed domain components 206, 207.
Such a cross-correlation function 500 will typically have a plurality of peaks 501, 502, which may be identified using any peak detection algorithm or threshold 503. The first peak 501 may be due to cross talk within the apparatus 200, 300. The second peak 502 may be indicative of the time taken by the calibration signal and may be used in determination of the time delay. Accordingly, the calibration device may be configured to determine the time delay based on identification of a peak 502 in the cross-correlation function 500 subsequent to an initial peak 501. It will be appreciated that other methods may be used to determine the component of the time between sending and receipt of the calibration signal that is attributable to the time delay introduced by at least the antenna and antenna circuitry.
Returning to
The method may include an optional step 601 prior to step 603 of providing for switching to the calibration mode, such as from the normal-operation mode. The method may further include the optional step of providing 602 for sending of a calibration signal from one of the first 202 and second antenna 203 to the other.
The instructions and/or flowchart steps in the above figures can be executed in any order, unless a specific order is explicitly stated. Also, those skilled in the art will recognize that while one example set of instructions/method has been discussed, the material in this specification can be combined in a variety of ways to yield other examples as well, and are to be understood within a context provided by this detailed description.
In some example embodiments the set of instructions/method steps described above are implemented as functional and software instructions embodied as a set of executable instructions which are effected on a computer or machine which is programmed with and controlled by said executable instructions. Such instructions are loaded for execution on a processor (such as one or more CPUs). The term processor includes microprocessors, microcontrollers, processor modules or subsystems (including one or more microprocessors or microcontrollers), or other control or computing devices. A processor can refer to a single component or to plural components.
In other examples, the set of instructions/methods illustrated herein and data and instructions associated therewith are stored in respective storage devices, which are implemented as one or more non-transient machine or computer-readable or computer-usable storage media or mediums. Such computer-readable or computer usable storage medium or media is (are) considered to be part of an article (or article of manufacture). An article or article of manufacture can refer to any manufactured single component or multiple components. The non-transient machine or computer usable media or mediums as defined herein excludes signals, but such media or mediums may be capable of receiving and processing information from signals and/or other transient mediums.
Example embodiments of the material discussed in this specification can be implemented in whole or in part through network, computer, or data based devices and/or services. These may include cloud, internet, intranet, mobile, desktop, processor, look-up table, microcontroller, consumer equipment, infrastructure, or other enabling devices and services. As may be used herein and in the claims, the following non-exclusive definitions are provided.
In one example, one or more instructions or steps discussed herein are automated. The terms automated or automatically (and like variations thereof) mean controlled operation of an apparatus, system, and/or process using computers and/or mechanical/electrical devices without the necessity of human intervention, observation, effort and/or decision.
It will be appreciated that any components said to be coupled may be coupled or connected either directly or indirectly. In the case of indirect coupling, additional components may be located between the two components that are said to be coupled.
In this specification, example embodiments have been presented in terms of a selected set of details. However, a person of ordinary skill in the art would understand that many other example embodiments may be practiced which include a different selected set of these details. It is intended that the following claims cover all possible example embodiments.
| Number | Date | Country | Kind |
|---|---|---|---|
| 17183089.6 | Jul 2017 | EP | regional |
