NOT APPLICABLE
NOT APPLICABLE
1. Technical Field
This invention relates generally to wireless communication systems and more particularly to antenna structures used in such wireless communication systems.
2. Description of Related Art
Communication systems are known to support wireless and wire lined communications between wireless and/or wire lined communication devices. Such communication systems range from national and/or international cellular telephone systems to the Internet to point-to-point in-home wireless networks to radio frequency identification (RFID) systems to radio frequency radar systems. Each type of communication system is constructed, and hence operates, in accordance with one or more communication standards. For instance, radio frequency (RF) wireless communication systems may operate in accordance with one or more standards including, but not limited to, RFID, IEEE 802.11, Bluetooth, global system for mobile communications (GSM), code division multiple access (CDMA), WCDMA, local multi-point distribution systems (LMDS), multi-channel-multi-point distribution systems (MMDS), LTE, WiMAX, and/or variations thereof. As another example, infrared (IR) communication systems may operate in accordance with one or more standards including, but not limited to, IrDA (Infrared Data Association).
For an RF wireless communication device to participate in wireless communications, it includes a built-in radio transceiver (i.e., receiver and transmitter) or is coupled to an associated radio transceiver (e.g., a station for in-home and/or in-building wireless communication networks, RF modem, etc.). The receiver is coupled to the antenna and includes a low noise amplifier, one or more intermediate frequency stages, a filtering stage, and a data recovery stage. The transmitter includes a data modulation stage, one or more intermediate frequency stages, and a power amplifier, which is coupled to the antenna.
Since a wireless communication begins and ends with the antenna, a properly designed antenna structure is an important component of wireless communication devices. As is known, the antenna structure is designed to have a desired impedance (e.g., 50 Ohms) at an operating frequency, a desired bandwidth centered at the desired operating frequency, and a desired length (e.g., ¼ wavelength of the operating frequency for a monopole antenna). As is further known, the antenna structure may include a single monopole or dipole antenna, a diversity antenna structure, an antenna array having the same polarization, an antenna array having different polarization, and/or any number of other electro-magnetic properties.
Two-dimensional antennas are known to include a meandering pattern or a micro strip configuration. For efficient antenna operation, the length of an antenna should be ¼ wavelength for a monopole antenna and ½ wavelength for a dipole antenna, where the wavelength (λ)=c/f, where c is the speed of light and f is frequency. For example, a ¼ wavelength antenna at 900 MHz has a total length of approximately 8.3 centimeters (i.e., 0.25*(3×108 m/s)/(900×106 c/s)=0.25*33 cm, where m/s is meters per second and c/s is cycles per second). As another example, a ¼ wavelength antenna at 2400 MHz has a total length of approximately 3.1 cm (i.e., 0.25*(3×108 m/s)/(2.4×109 c/s)=0.25*12.5 cm).
While two-dimensional antennas provide reasonable antenna performance for many wireless communication devices, there are issues when the wireless communication devices require full duplex operation and/or multiple input and/or multiple output (e.g., single input multiple output, multiple input multiple output, multiple input single output) operation. For instance, antenna arrays and other antenna structures use antennas with the same radiation pattern and bandwidth.
The wireless communication device 100 includes a baseband processing module 102, a receiver section 104, a plurality of low noise amplifiers, a transmitter section 106, a plurality of power amplifiers, a processing module 115, and radio front-end module 108. The radio front-end module 108 includes power amplifiers (pa), low noise amplifiers (lna), a reconfigurable antenna array 110, an antenna processing circuit 112, and a configuration module 114. The reconfigurable antenna array 110 includes reconfigurable antennas, each of which has a different radiation pattern and a frequency bandwidth, which collectively form a radiation pattern and frequency bandwidth for a reconfigurable antenna array 110.
In an example of transmitting an outbound signal 120, the baseband processing module 102 converts outbound data 116 (e.g., voice, text, audio, video, graphics, etc.) into one or more outbound symbol streams 118 in accordance with one or more wireless communication standards (e.g., GSM, CDMA, WCDMA, HSUPA, HSDPA, WiMAX, EDGE, GPRS, IEEE 802.11, Bluetooth, ZigBee, universal mobile telecommunications system (UMTS), long term evolution (LTE), IEEE 802.16, evolution data optimized (EV-DO), etc.). Such a conversion includes one or more of: scrambling, puncturing, encoding, interleaving, constellation mapping, modulation, frequency spreading, frequency hopping, beamforming, space-time-block encoding, space-frequency-block encoding, frequency to time domain conversion, and/or digital baseband to intermediate frequency conversion. Note that the baseband processing module 102 converts the outbound data 116 into a single outbound symbol stream 118 for Single Input Single Output (SISO) communications and/or for Multiple Input Single Output (MISO) communications and converts the outbound data 116 into multiple outbound symbol streams 188 for Single Input Multiple Output (SIMO) and Multiple Input Multiple Output (MIMO) communications.
The baseband processing module 102 provides the outbound symbol stream(s) 118 to an up conversion circuit of the transmit section 106, which converts the outbound symbol stream(s) 118 into one or more up converted signals (e.g., signals in one or more frequency bands 800 MHz, 1800 MHz, 1900 MHz, 2000 MHz, 2.4 GHz, 5 GHz, 60 GHz, etc.). The up conversion circuit may have a direct conversion topology or a super-heterodyne topology and may include discrete digital components and/or analog circuitry. In addition, the up conversion circuit may receive and process the outbound symbol stream(s) 118 as Cartesian coordinates, as polar coordinates, and/or as hybrid polar-Cartesian coordinates.
A transmit (TX) output circuit of the transmitter section 106 receives the one or more up converted signals and provides them to one or more of the power amplifiers (pa). The transmit output circuit may include a splitter for providing an up converted signal to multiple power amplifiers such that, when the signals are transmitted, they are combined in air, which increases the transmit power. In this manner, one or more of the expensive discrete components (e.g., surface acoustic wave (SAW) filters, off-chip power amplifiers, duplexers, inductors, and/or capacitors) may be omitted. In addition, or in the alternative, the transmit output circuit may include one or more phase shift circuits to phase shift the one or more up converted signals to facilitate beamforming. The transmit output circuit may further include, or include in the alternative, a polar coordinate drive to facilitate polar coordinate outbound signals.
Regardless of the specific implementation of the transmit output circuit, one or more power amplifiers receives the up-converted signal(s) and amplifies them to produce outbound signal(s) 120. The power amplifier(s) provide the outbound signal(s) 120 to the antenna processing circuit 112. The antenna processing circuit 112 provides components of the outbound signal to the reconfigurable antenna array 110 for transmission. For example, the components of the outbound signal may be created by the transmit output circuit or the antenna processing circuit may produce them from the outbound signal 120. Note that the reconfigurable antenna array 110 is configured in accordance with configuration signals from the configuration module 114.
In an example of receiving an inbound signal 122, the reconfigurable antenna array 110 receives respective components of the inbound signal 122 and provides them to the antenna processing circuit 112. The antenna processing circuit 112 provides the components of the inbound signal 122 to one or more low noise amplifiers via the transmit/receive isolation module 114.
The low noise amplifiers amplify the inbound signal components to produce amplified inbound signal(s). The low noise amplifier(s) provide the amplified inbound signal components to a receive (RX) input circuit of the receiver section 104, which is a complimentary circuit to the transmit output circuit of the transmitter section. For instance, if the transmit output circuit includes a splitter, the receive input circuit includes a combiner to combine the components into the inbound signal 122.
Alternatively, the antenna processing circuit 112 combines the components into one or more inbound signals 122 that are provided to one or more of the low noise amplifiers via one or more transmit/receive isolation modules 114. The low noise amplifier(s) amplifies the one or more inbound signals 122 and provides them to the receive input circuit of the receiver section 104.
The receive input circuit provides the inbound signal to a down conversion circuit of the receiver section, which converts the inbound signal into one or more inbound symbol streams 124. The down conversion circuit may have a direct conversion topology or a super-heterodyne topology and may include discrete digital components and/or analog circuitry. In addition, the down conversion circuit may receive and process the inbound signals as Cartesian coordinates, as polar coordinates, and/or as hybrid polar-Cartesian coordinates.
The baseband processing module 102 converts the inbound symbol stream(s) 124 into inbound data 126 (e.g., voice, text, audio, video, graphics, etc.) in accordance with one or more wireless communication standards. Such a conversion may include one or more of: digital intermediate frequency to baseband conversion, time to frequency domain conversion, space-time-block decoding, space-frequency-block decoding, demodulation, frequency spread decoding, frequency hopping decoding, beamforming decoding, constellation demapping, deinterleaving, decoding, depuncturing, and/or descrambling. Note that the processing module 102 converts a single inbound symbol stream 124 into the inbound data 126 for Single Input Single Output (SISO) communications and/or for Multiple Input Single Output (MISO) communications and converts multiple inbound symbol streams 124 into the inbound data 126 for Single Input Multiple Output (SIMO) and Multiple Input Multiple Output (MIMO) communications.
The wireless communication device 100 may be implemented using one or more integrated circuits (IC) and one or more substrates (e.g., printed circuit boards), where an IC includes one or more IC dies and an IC package substrate. For example, the antenna processing circuit 112, the power amplifiers, and the low noise amplifiers may be implemented on the one or more IC dies and the reconfigurable antenna 110 on an IC package substrate and/or one of the substrates. As another example, one or more of the baseband processing module 102, the receiver section 104, the transmitter section 106, and the processing module 114 may also be implemented on the one or more IC dies.
As shown, the first reconfigurable antenna 200 has a shorter, wider radiation pattern than that of the second reconfigurable antenna 200. When the first reconfigurable antenna 200 and the second reconfigurable antenna 202 are used in the same antenna array, their respective radiation patterns combine in air to provide a broader, more diverse radiation pattern than achieved separately. Combining the first and second radiation patterns 208-210 creates a taller radiation pattern than achieved with the first reconfigurable antenna 200 alone and a wider radiation pattern than achieved by using the second reconfigurable antenna 202 alone therefore improving the diversity and capacity of the antenna array 110 in comparison to an antenna array that includes similarly shaped antennas.
In an example of operation, the antennas are configured to support three concurrent or time duplexed communications via the channels of interest. A first communication (RX and TX signal 1) is conveyed over a first channel, a second communication (RX and TX signal 2) is conveyed over a second channel, and a third communication has transmit signals (TX signal 3) conveyed over channel 5 and receive signals (RX signal 3) conveyed over channel 4. The communications may be separate communications and/or communications of a MIMO communication.
As shown, the first reconfigurable antenna 200 has a radiation pattern that is representative of the first geometric shape 400 and the second reconfigurable antenna 202 has a radiation pattern 410 that is representative of the second geometric shape). For example, a spiral or circular shaped antenna will have a circular radiation lobe with a circular polarization while a dipole antenna will have two radiation lobes with a linear polarization.
The inner interwoven spiral antenna section 1000 has a geometric shape of an elliptical interwoven spiral, a triangular-shaped interwoven spiral, a square-shaped interwoven spiral, a rectangular-shaped interwoven spiral, a poly-sided shaped interwoven spiral (e.g., five sides or more), a circular Celtic spiral, an elliptical Celtic spiral, a circular Archimedean spiral shape, an elliptical Archimedean spiral shape, and/or an equiangular interwoven spiral shape. As used herein, an interwoven spiral means a first spiral trace of a spiral shape and a second spiral trace having a complementary or mirrored spiral shape.
The outer interwoven spiral antenna section 1002 has a geometric shape that is a continuation of the geometric shape of the inner interwoven spiral antenna section 1000. For example, when the inner interwoven spiral antenna section 1000 has a circular Celtic spiral shape, the outer interwoven spiral antenna section 1002 has a circular Celtic spiral shape such that, when coupled together, the inner and outer interwoven spiral antenna sections 1000 and 1002 form a larger circular Celtic spiral antenna.
The operating characteristics of the reconfigurable antenna are based on its physical properties. For instance, the reconfigurable antenna's circumference is a factor for a lower frequency cutoff of a frequency band of operation of the antenna. Further, distance of the excitation region (e.g., distance between excitation points and/or radius of an inner most turn) is a factor of an upper frequency cutoff of the frequency band of operation. Still further, the interwoven spiral pattern inverts an opposite radiation lobe of the antenna to approximately double the gain of the spiral antenna. Even further, the number of turns provides different circular polarization radiation patterns. Yet further, the trace width, distance between traces, length of each spiral section, distance to a ground plane, and/or use of an artificial magnetic conductor plane affect the quality factor, radiation pattern, impedance (which is fairly constant over the bandwidth), gain, and/or other characteristics of the reconfigurable antenna.
In a specific example, assume that inner interwoven spiral antenna section 1000 has a 20 mm radius, which equates to a 125.66 mm circumference (e.g., 2*π*20=125.66 mm circumference). Such a circumference corresponds to a low frequency cutoff of approximately 2 GHz. Further assume that the excitation region uses the first excitation points, which has a distance of approximately 5 mm, which establishes a high frequency cutoff of approximately 8 GHz. As such, inner interwoven antenna section 1000 has a bandwidth of 2-8 GHz, centered at 5 GHz.
In another specific example, assume that inner interwoven spiral antenna section 1000 is coupled to the outer interwoven spiral antenna section and collectively have a 60 mm radius, which equates to an approximate circumference of 375 mm. Such a circumference corresponds to a low frequency cutoff of approximately 800 MHz. Further assume that the excitation region uses the second excitation points, which has a distance of approximately 8 mm, which establishes a high frequency cutoff of approximately 5 GHz. As such, inner interwoven antenna section 1000 has a bandwidth of 0.8-5 GHz, centered at 2.5 GHz.
The reconfigurable antenna of
The reconfigurable antenna may be configured in a variety of ways. For example, when a configuration signal is in a first state, the first pair of excitation points 1004 are selected and the outer interwoven spiral antenna section 1102 is coupled to the inner interwoven spiral antenna section 1000 to provide a first version of the frequency bandwidth as shown in
When the configuration signal is in a second state, the second pair of excitation points 1006 are selected and the outer interwoven spiral antenna section 1002 is coupled to the inner interwoven spiral antenna section 1000 to provide a second version of the frequency bandwidth as shown in
When the configuration signal is in a third state, the first pair of excitation points 1004 are selected and the outer interwoven spiral antenna section 1002 is not coupled to the inner interwoven spiral antenna section 1000 to provide a third version of the frequency bandwidth as shown in
When the configuration signal is in a fourth state, the second pair of excitation points 1006 are selected and the outer interwoven spiral antenna section 1002 is not coupled to the inner interwoven spiral antenna section 1000 to provide a fourth version of the frequency bandwidth as shown in
The operating characteristics of the reconfigurable antenna are based on its physical properties. For instance, the reconfigurable antenna's shape, area, and circumference are factors for the radiation pattern and/or a lower frequency cutoff of a frequency band of operation of the antenna. Further, distance of the excitation region (e.g., distance between excitation points) is a factor of at least one of a center frequency and an upper frequency cutoff of the frequency band of operation. Still further, the shape and the area of the radiator 1200 and the distance between the selected excitation points affect the quality factor, radiation pattern, impedance (which is fairly constant over the bandwidth), gain, and/or other characteristics of the reconfigurable antenna.
For example, the antenna processing circuit 112 couples, via a transmission line, to one of the excitation points 1202 at a specific location such that the reconfigurable antenna functions similarly to a microstrip antenna. The size and shape of the radiator 1202 with respect to the selected excitation point are factors in the operating characteristics of the antenna. For instance, the length of the radiator with respect to the selected excitation point is a factor in determining the center frequency and the width of the radiator with respect to the selected excitation point is a factor in establishing the impedance of the antenna and its radiation pattern. Thus, by selecting different excitation points, the effective length and width of the antenna are changed, thus changing the center frequency, impedance, and/or radiation pattern.
As another example, the antenna processing circuit 112 couples, via a transmission line, to a pair of the excitation points 1202 at specific locations such that the reconfigurable antenna functions similarly to a loop antenna. The size and shape of the radiator 1202 with respect to the selected excitation point are factors in establishing the radiation pattern of the antenna in establishing the frequency band of operation. The distance between the selected excitation points 1202 is a factor for determining the center frequency and/or a high frequency cutoff of a frequency band of operation. Thus, by selecting different excitation points, the effective length and width of the antenna are changed, the center frequency, frequency band of operation, and/or radiation pattern are changed.
The reconfigurable antenna of
In an example of operation, the antenna processing circuit 112 enables one or more excitation points 1202 and 1302 for each of the radiators 1200 and 1300. For instance, the antenna processing circuit 112 selects an excitation point 1202 such that the first reconfigurable antenna functions similarly to a microstrip antenna and selects a pair of excitation points 1302 such that the second reconfigurable antenna functions similarly to a loop antenna. As such, each reconfigurable antenna may transceive the same inbound and outbound signals or different inbound and outbound signals.
As may be used herein, the terms “substantially” and “approximately” provides an industry-accepted tolerance for its corresponding term and/or relativity between items. Such an industry-accepted tolerance ranges from less than one percent to fifty percent and corresponds to, but is not limited to, component values, integrated circuit process variations, temperature variations, rise and fall times, and/or thermal noise. Such relativity between items ranges from a difference of a few percent to magnitude differences. As may also be used herein, the term(s) “operably coupled to”, “coupled to”, and/or “coupling” includes direct coupling between items and/or indirect coupling between items via an intervening item (e.g., an item includes, but is not limited to, a component, an element, a circuit, and/or a module) where, for indirect coupling, the intervening item does not modify the information of a signal but may adjust its current level, voltage level, and/or power level. As may further be used herein, inferred coupling (i.e., where one element is coupled to another element by inference) includes direct and indirect coupling between two items in the same manner as “coupled to”. As may even further be used herein, the term “operable to” or “operably coupled to” indicates that an item includes one or more of power connections, input(s), output(s), etc., to perform, when activated, one or more its corresponding functions and may further include inferred coupling to one or more other items. As may still further be used herein, the term “associated with”, includes direct and/or indirect coupling of separate items and/or one item being embedded within another item. As may be used herein, the term “compares favorably”, indicates that a comparison between two or more items, signals, etc., provides a desired relationship. For example, when the desired relationship is that signal 1 has a greater magnitude than signal 2, a favorable comparison may be achieved when the magnitude of signal 1 is greater than that of signal 2 or when the magnitude of signal 2 is less than that of signal 1.
As may also be used herein, the terms “processing module”, “processing circuit”, and/or “processing unit” may be a single processing device or a plurality of processing devices. Such a processing device may be a microprocessor, micro-controller, digital signal processor, microcomputer, central processing unit, field programmable gate array, programmable logic device, state machine, logic circuitry, analog circuitry, digital circuitry, and/or any device that manipulates signals (analog and/or digital) based on hard coding of the circuitry and/or operational instructions. The processing module, module, processing circuit, and/or processing unit may be, or further include, memory and/or an integrated memory element, which may be a single memory device, a plurality of memory devices, and/or embedded circuitry of another processing module, module, processing circuit, and/or processing unit. Such a memory device may be a read-only memory, random access memory, volatile memory, non-volatile memory, static memory, dynamic memory, flash memory, cache memory, and/or any device that stores digital information. Note that if the processing module, module, processing circuit, and/or processing unit includes more than one processing device, the processing devices may be centrally located (e.g., directly coupled together via a wired and/or wireless bus structure) or may be distributedly located (e.g., cloud computing via indirect coupling via a local area network and/or a wide area network). Further note that if the processing module, module, processing circuit, and/or processing unit implements one or more of its functions via a state machine, analog circuitry, digital circuitry, and/or logic circuitry, the memory and/or memory element storing the corresponding operational instructions may be embedded within, or external to, the circuitry comprising the state machine, analog circuitry, digital circuitry, and/or logic circuitry. Still further note that, the memory element may store, and the processing module, module, processing circuit, and/or processing unit executes, hard coded and/or operational instructions corresponding to at least some of the steps and/or functions illustrated in one or more of the Figures. Such a memory device or memory element can be included in an article of manufacture.
The present invention has been described above with the aid of method steps illustrating the performance of specified functions and relationships thereof. The boundaries and sequence of these functional building blocks and method steps have been arbitrarily defined herein for convenience of description. Alternate boundaries and sequences can be defined so long as the specified functions and relationships are appropriately performed. Any such alternate boundaries or sequences are thus within the scope and spirit of the claimed invention. Further, the boundaries of these functional building blocks have been arbitrarily defined for convenience of description. Alternate boundaries could be defined as long as the certain significant functions are appropriately performed. Similarly, flow diagram blocks may also have been arbitrarily defined herein to illustrate certain significant functionality. To the extent used, the flow diagram block boundaries and sequence could have been defined otherwise and still perform the certain significant functionality. Such alternate definitions of both functional building blocks and flow diagram blocks and sequences are thus within the scope and spirit of the claimed invention. One of average skill in the art will also recognize that the functional building blocks, and other illustrative blocks, modules and components herein, can be implemented as illustrated or by discrete components, application specific integrated circuits, processors executing appropriate software and the like or any combination thereof.
The present invention may have also been described, at least in part, in terms of one or more embodiments. An embodiment of the present invention is used herein to illustrate the present invention, an aspect thereof, a feature thereof, a concept thereof, and/or an example thereof. A physical embodiment of an apparatus, an article of manufacture, a machine, and/or of a process that embodies the present invention may include one or more of the aspects, features, concepts, examples, etc. described with reference to one or more of the embodiments discussed herein. Further, from figure to figure, the embodiments may incorporate the same or similarly named functions, steps, modules, etc. that may use the same or different reference numbers and, as such, the functions, steps, modules, etc. may be the same or similar functions, steps, modules, etc. or different ones.
Unless specifically stated to the contra, signals to, from, and/or between elements in a figure of any of the figures presented herein may be analog or digital, continuous time or discrete time, and single-ended or differential. For instance, if a signal path is shown as a single-ended path, it also represents a differential signal path. Similarly, if a signal path is shown as a differential path, it also represents a single-ended signal path. While one or more particular architectures are described herein, other architectures can likewise be implemented that use one or more data buses not expressly shown, direct connectivity between elements, and/or indirect coupling between other elements as recognized by one of average skill in the art.
The term “module” is used in the description of the various embodiments of the present invention. A module includes a processing module, a functional block, hardware, and/or software stored on memory for performing one or more functions as may be described herein. Note that, if the module is implemented via hardware, the hardware may operate independently and/or in conjunction software and/or firmware. As used herein, a module may contain one or more sub-modules, each of which may be one or more modules.
While particular combinations of various functions and features of the present invention have been expressly described herein, other combinations of these features and functions are likewise possible. The present invention is not limited by the particular examples disclosed herein and expressly incorporates these other combinations.
The present U.S. Utility Patent Application claims priority pursuant to 35 U.S.C. §119(e) to the following U.S. Provisional Patent Application which is hereby incorporated herein by reference in its entirety and made part of the present U.S. Utility Patent Application for all purposes: 1. U.S. Provisional Application Ser. No. 61/876,528, entitled “CONFIGURABLE ANTENNA STRUCTURE WITH CONFIGURABLE ANTENNAS AND APPLICATIONS THEREOF,” filed Sep. 11, 2013, pending.
Number | Date | Country | |
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61876528 | Sep 2013 | US |