Calculating Variance of Beamforming Parameters in Phased Arrays

Abstract

Systems and methods for operating a phased array are described. In one example, the system can convert a desired beam direction of a desired beam into at least one phase gradient parameter. The phased array can include a plurality of antennas connected to a plurality of front-end circuits of a beamforming circuit, each antenna may be connected to a respective front-end circuit. For each antenna of the plurality of antennas, the system can determine a phase shift parameter of the antenna based on the at least one phase gradient parameter and a physical location of the antenna. For each antenna of the plurality of antennas, the system can map the determined phase shift parameter of the antenna to a control setting of a front-end circuit connected to the antenna.

Description

[Technical Field]

[0001] This application relates to antennas, phased arrays, beamforming, integrated circuits and programs, and to computer-implemented methods and systems for phased array systems. [Background technology]

[0002] A phased array system can include a beamforming integrated circuit (IC) and multiple antennas. A phased array system can use multiple antenna signal paths, each with a variable time delay. For a phased array system implemented as a receiver (or a receive channel in a transceiver), the beamforming circuitry can use the propagation delay created by the variable time delay in each antenna signal path of the signal received by the phased array, resulting in higher reception gain for signals arriving from a particular direction. For a phased array system implemented as a transmitter (or a transmit channel in a transceiver), the beamforming circuitry can control the time delay difference between successive antenna signal paths of multiple antennas to generate an electromagnetic beam with a specific direction. The beamforming IC can use the different time delay variations to direct the electromagnetic beam in different directions. Summary of the Invention

[0003] In some examples, a method for operating a phased array is generally described. The method may include converting a desired beam direction of a desired beam into at least one phase gradient parameter. The phased array may include a plurality of antennas connected to a plurality of front-end circuits of a beamforming circuit, each antenna being connected to a respective front-end circuit. The method may further include, for each antenna of the plurality of antennas, determining a phase shift parameter of the antenna based on the at least one phase gradient parameter and a physical location of the antenna. The method may further include, for each antenna of the plurality of antennas, mapping the determined phase shift parameter of the antenna to a control setting of a front-end circuit connected to the antenna.

[0004] In some examples, a system for operating a phased array is generally described. The system may include a first device, a phased array, and a second device connected to the first device and multiple front-end circuits. The phased array may include multiple antennas connected to multiple front-end circuits of a beamforming circuit. The first device may be configured to convert a desired beam direction of a desired beam into at least one phase gradient parameter. The first device may be further configured to transmit the at least one phase gradient parameter to a second device. The second device may be configured to receive the at least one phase gradient parameter. The second device may be further configured to determine, for each antenna of the multiple antennas, a phase shift parameter of the antenna based on the at least one phase gradient parameter and a physical location of the antenna. The second device may be further configured to map, for each antenna of the multiple antennas, the determined phase shift parameter of the antenna to a control setting of a front-end circuit connected to the antenna.

[0005] In some examples, an apparatus for operating a phased array is generally described. The apparatus may include a plurality of antennas and a beamforming circuit including a plurality of front-end circuits connected to the plurality of antennas. The beamforming circuit may be configured to receive at least one phase gradient parameter from a device. The at least one phase gradient parameter is based on a desired beam direction of a desired beam. The beamforming circuit may be further configured to determine, for each antenna of the plurality of antennas, a phase shift parameter for the antenna based on the at least one phase gradient parameter and a physical location of the antenna. The beamforming circuit may be further configured to map, for each antenna of the plurality of antennas, the determined phase shift parameter for the antenna to a control setting of a front-end circuit connected to the antenna.

[0006] Further features, as well as the structure and operation of various embodiments, are described in detail below with reference to the accompanying drawings, where like reference numbers indicate identical or functionally similar elements. [Brief explanation of the drawings]

[0007] [Figure 1A] 1 is an exemplary system capable of performing distributed calculations of beamforming parameters for a phased array in one embodiment. [Figure 1B] 1 is another exemplary system capable of implementing a distribution calculation of beamforming parameters for a phased array in one embodiment. [Figure 2] FIG. 10 illustrates an exemplary mapper that can be used to perform variance calculations of phased array beamforming parameters in one embodiment. [Figure 3] FIG. 10 illustrates another exemplary mapper that can be used to perform variance calculations of phased array beamforming parameters in one embodiment. [Figure 4A]FIG. 10 illustrates exemplary antenna patterns for implementation of distributed calculation of beamforming parameters for a phased array in one embodiment. [Figure 4B] FIG. 10 illustrates exemplary antenna patterns for implementation of distributed calculation of beamforming parameters for a phased array in one embodiment. [Figure 4C] FIG. 10 illustrates exemplary antenna patterns for implementation of distributed calculation of beamforming parameters for a phased array in one embodiment. [Figure 5] 1 is a flow diagram for calculating the variance of beamforming parameters for a phased array in one embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0008] Traditionally, digital control circuits for a phased array front end (e.g., digital control circuits for controlling parameters such as gain and phase) may each include a beam table in on-chip memory, with each row of the beam table storing settings corresponding to a given beam direction. However, as the number of antenna elements in a phased array increases, beamwidths become narrower and more beam directions may be required to cover a region of interest in space. Therefore, these beam tables can become large, and beam-finding algorithms may need to search a much larger number of beam table entries. For example, in smaller phased arrays (e.g., 16 antenna elements with a beamwidth of approximately 20 degrees), each beam table in each front-end circuit may have relatively few entries (e.g., less than 100 entries). However, large phased arrays (e.g., 256 or more antennas) may have a large number of entries in each beam table in each front-end circuit. For example, a phased array with 1024 antennas with a beamwidth of 1 degree may have approximately 2000 entries in each lookup table of each front-end circuit, making exhaustive searching of the lookup tables impractical and requiring a relatively large on-chip area to implement these lookup tables.

[0009] FIG. 1A illustrates an exemplary system capable of implementing distributed calculation of beamforming parameters for a phased array in one embodiment. System 100 may be a radio frequency (RF) transmission system implemented by a communication device such as an RF transmitter, an RF receiver, or an RF transceiver. System 100 may be configured to operate at general radio frequency, millimeter wave frequencies, or microwave frequencies, or a combination thereof. System 100 may be part of a wireless communication network, such as a fourth generation (4G) wireless communication system, a fifth generation (5G) wireless communication system, a satellite communication system, a point-to-point communication system such as a common data link, or other type of wireless communication network, or a combination thereof.

[0010] The system 100 may include a circuit 101, one or more beamforming integrated circuits (ICs) 102, multiple antennas 103, and a circuit 112. The one or more beamforming ICs 102 and the multiple antennas 103 may form a phased array system. The circuit 101 may be part of an RF communication device, such as a radio frequency (RF) transmitter, an RF receiver, a transmit channel of an RF transceiver, or a receive channel of an RF transceiver. For example, the circuit 101 may include a baseband processor, a mixer circuit such as an up-down converter, a filter, a memory device, a local oscillator, a digital-to-analog converter (DAC) (if the circuit 101 is an RF transmitter or a transmit channel of an RF transceiver), an analog-to-digital converter (ADC) (if the circuit 101 is an RF receiver or a receive channel of an RF transceiver), a signal generator, a microcontroller, or other types of components or integrated circuits belonging to an RF communication device, or a combination thereof. 1A can be configured to output RF signals to the beamforming IC 102 if the phased array system is intended to operate as a transmitter. In examples where the circuit 101 is part of an RF transceiver or receiver, the circuit 101 can also be configured to receive RF signals from the beamforming IC 102. The RF signals exchanged between the circuit 101 and the beamforming IC 102 can be radio frequency, millimeter wave frequency, or microwave frequency signals capable of carrying information or data.

[0011] The plurality of antennas 103 are antennas 1031 to 1033. N Each of the antennas 103 can output an RF signal having a respective amplitude and phase. In one example, the system 100 can include M beamforming ICs 102, which can be identical to one another. In one example, the beamforming ICs 102 M Uses the beamforming IC102 MEach of the beamforming ICs 102 may include a circuit 120, a mapper 130, and a plurality of front-end circuits 108. Each of the beamforming ICs 102 may include a front-end circuit 1081-108. N The front-end circuit 108 may include N front-end circuits 108, each including a power amplifier, a gain control circuit, a phase shifter, or other types of components or ICs capable of implementing different beamforming techniques, or a combination thereof. For example, the front-end circuit 1081 may include a gain control circuit 1091 and a phase shifter 1101, and the front-end circuit 108 N is a gain control circuit 109 N and a phase shifter 110 N Furthermore, each front-end circuit may be connected to one of the plurality of antennas 103. N Each of the phase shifters may receive a phase shift control setting for controlling the phase of an RF signal output by a connected antenna. N Each gain control circuit may receive a gain control setting to control the gain of the RF signal output by the connected antenna. The beam steering may be performed by a respective phase shifter (e.g., phase shifters 1101-1102) of the front-end circuit 108. N ) may be implemented. Phase delays across the front-end circuitry 108 can create interference patterns that can focus the beam in a particular direction. The beam 104 can have a field pattern and beam direction that can be based on gain and phase parameters set in the front-end circuitry 108.

[0012] In one example, the system 100 can generate a desired beam 104 having a desired beam direction 115 and a desired magnitude (see coordinate system 114 in FIG. 1A ). To generate the desired beam 104, the circuit 112 can first determine a set of phase gradient parameters 116. In one example, the circuit 112 can be a device including components such as a field programmable gate array (FPGA) chip or a processor such as a central processing unit (CPU) of a computing device configured to determine the set of phase gradient parameters 116. The set of phase gradient parameters 116 can include a first phase gradient parameter denoted as α and a second phase gradient parameter denoted as β. The circuit 112 can determine the set of phase gradient parameters 116 based on the beam angle of the desired beam direction 115, the wavelength of the desired beam 104, and the spacing between the multiple antennas 103. The beam angle of the desired beam direction 115 can include angular components θ and φ. The circuit 112 can determine a phase gradient parameter α based on θ and φ, a wavelength λ of the desired beam 104, and a minimum unit spacing between the multiple antennas 103 in the x-direction, denoted as dx. The circuit 112 can determine a phase gradient parameter β based on θ and φ, a wavelength λ of the desired beam 104, and a minimum unit spacing between the multiple antennas 103 in the y-direction, denoted as dy. In one example, the following equation can represent the relationship between α, β, θ, φ, λ, dx, and dy:

[0013]

number

[0014] In one example, each beamforming IC 102 M The set of N specific locations 118 of the antennas 103 supported by x , η y matrix L containing M It can be expressed as:

[0015] The set of phase gradient parameters 116 may be input to each of the beamforming ICs 102. In addition, a set of antenna positions 118 may be input to each corresponding beamforming IC 102M. In one example, the circuit 112 may broadcast the set of phase gradient parameters 116 to the beamforming ICs 102. The circuit 120 of each beamforming IC 102 may receive the set of phase gradient parameters 116 from the circuit 112. The circuit 120 of each beamforming IC may receive the set of N antenna positions 118 from the circuit 112. The circuit 120 of the beamforming IC 102 may calculate, for each ith antenna of the plurality of antennas 103, Φ i where i=1...N. In one example, the phase shift parameters 122 may be an ideal phase shift required for the connected front-end circuitry or antenna. For example, the phase shift parameter Φ for the ith antenna may be i may be the ideal phase shift required for the ith antenna to contribute to forming the desired beam 104 in the desired beam direction 105. The circuit 120 can determine the phase shift parameters 122 for each antenna based on the set of phase gradient parameters 116 and the physical location of the corresponding antenna. For example, the circuit 120 can determine Φ for the antenna 1031 based on α, β, and the physical location of the antenna 1031. The circuit 120 can transmit the phase shift parameters 122 to the mapper 130. In one example, the following equation can be used to determine Φ for the antenna 1031 based on α, β, and the physical location of the antenna 1031: i The relationship can be expressed as: Φ xy =η x α+η y β where Φ xy denotes the i-th antenna located at point (x, y) on the xy plane (see coordinate system 114), and η x denotes the position of the ith antenna in the x direction, and η y denotes the position of the i-th antenna in the y direction.

[0016] It should be noted that the circuit 112 may be implemented off-chip (e.g., external to the beamforming IC 102), thereby allowing the calculation or determination of the set of phase gradient parameters 116 to be performed off-chip. The calculation or determination of the phase shift parameters 122 may be performed by the circuit 120 of the beamforming IC 102. Because the nonlinear nature of the calculation of the set of phase gradient parameters 116 may require more power than a linear calculation (e.g., the calculation of the phase shift parameters 122), offloading the calculation of the set of phase gradient parameters 116 to the circuit 112 may result in the beamforming IC consuming relatively less power. For example, the calculation of the set of phase gradient parameters 116 may be trigonometric and frequency-dependent. By offloading the calculation of the set of phase gradient parameters 116 to the circuit 112, the area required for the beamforming IC (e.g., the beamforming IC 102) may be smaller, and the overall calculation may be performed faster.

[0017] It should be noted that performing the calculation of the set of phase gradient parameters 116 based on the finest antenna spacing (with a precision limited only by the number of bits used for this representation) and the calculation of the phase shift parameters 122 based on specific antenna positions 188 makes it possible to support a wide variety of antenna array configurations, including configurations in which the antennas are not arranged on a uniformly spaced grid.

[0018] It is further noted that while the series of calculations to determine the set of phase gradient parameters 116 depends on the desired beam direction 115 (e.g., a separate calculation is required for each beam direction), the set of N antenna positions 118 is not expected to change dynamically. Thus, in one example, each set of N antenna positions 118 is input into the corresponding beamforming IC 102M only once during system initialization.

[0019] In one example, mapper 130 may be a circuit including one or more of a processing element, a look-up table, a memory device, or an IC such as a decoder, or a combination thereof. i may be configured to map Φ to different control settings of the front-end circuit 108. For example, the mapper 130 may map Φ to control settings including a gain control setting 1321 and a phase shift control setting 1341, and input the control settings 1321, 1341 to the front-end circuit 108. In one example, the mapper 130 may map Φ i In another example, the mapper 130 may include a look-up table that stores associations between different values ​​of Φ and different control settings (e.g., different values ​​of phase and gain control settings). i The mapper 130 may include multiple lookup tables, such as one lookup table per front-end circuit 108, that store associations between different values ​​of and different control settings. In another example, the mapper 130 may implement a static random access memory (SRAM) device to store the associations. The different control settings mapped to the front-end circuit 108 may configure the multiple antennas 103 to generate desired beams 104.

[0020] Another exemplary embodiment of system 100 is shown in FIG. 1B. In the example shown in FIG. 1B, antennas 103 can form receive beams 117, and each of antennas 103 can receive an RF signal. Front-end circuitry 108 can further include receive channel components, such as a bandpass filter to reduce image response, an RF amplifier or low-noise amplifier (LNA) to amplify weak signals without contaminating them with noise, a local oscillator (LO) to generate an LO signal to be mixed with the RF signal received in the direction of beam 117, and a mixer to mix the LO signal with the RF signal received in the direction of beam 117. For simplicity, FIG. 1B only shows front-end circuits 1081, 1082, and 1083 to illustrate the receive channels implemented by front-end circuitry 108. N RF amplifiers 1071, 1072, 107 N The front-end circuit 108 may include a switch for switching the front-end circuit 108 between a transmission mode and a reception mode. N Each of the phase shifters may receive a phase shift control setting for controlling the phase of an RF signal received by a connected antenna. N Each gain control circuit may receive a gain control setting to control the gain of the RF signal received by the connected antenna. The beam steering may be performed by a respective phase shifter (e.g., phase shifters 1101-1102) of the front-end circuit 108. N ) may be implemented. Phase delays across the front-end circuitry 108 can cause signals to coherently combine when they arrive at the antenna array from a particular direction, forming a receive beam in that direction. The signal combiners are not shown for simplicity. The beam 117 can have a field pattern and beam direction that can be based on gain and phase parameters set in the front-end circuitry 108.

[0021] The beam 117 is transmitted to the corresponding antenna 103N The circuit 120 calculates the gradient parameter 127α corresponding to the receive beam 117. R and β R and transmits these parameters to the circuit 112. The circuit 120 of the beamforming IC 102 can determine Φ for each ith antenna of the plurality of antennas 103. i where i=1...N. The circuit 120 can determine the phase shift parameters 122 for each antenna based on a set of receive phase gradient parameters 127 and the physical location of the corresponding antenna. The circuit 120 can transmit the phase shift parameters 122 to a mapper 130. The mapper 130 can determine the desired phase shift parameters Φ for each antenna. i may be mapped to a corresponding set of front-end control settings, and these settings may be input to each front-end circuit 108. In one example, the control settings for front-end circuit 1081 corresponding to phase shift parameter Φ include phase shifter control setting 1341 and receive gain control setting 1321.

[0022] FIG. 2 illustrates an exemplary mapper that can be used to perform distributed calculations of beamforming parameters for a phased array in one embodiment. In the example illustrated in FIG. 2, the mapper 130 can include a decoder 202 and a mapping table 204. In one example, the mapping table 204 can be implemented as a lookup table that translates different values ​​of the phase shift parameter 122 into different control settings. In another example, the mapping table 204 can be implemented as an SRAM device that stores associations between different values ​​of the phase shift parameter 122 and different control settings. In another example, the mapping table 204 can be a data structure, or data stored in memory, or a database received from another processor or another device. The mapping table 204 includes entries E1 through E2. kThe mapping table 204 may include k entries, denoted as k, where k is less than the number of possible beam directions that can be achieved by the multiple antennas 103. Each entry in the mapping table 204 may store a control setting including a phase control parameter and a gain control parameter.

[0023] The decoder 202 detects Φ1 to Φ N , Φ 1 , Φ 2 , Φ 3 , Φ 4 , Φ 5 , Φ 6 , Φ 7 , Φ 8 , Φ 9 , Φ 10 , Φ 11 , Φ 12 , Φ 13 , Φ 14 , Φ 15 , Φ 16 , Φ 17 , Φ 18 , Φ 19 , N Entry E3, E k , and E1, respectively. In some examples, two or more phase shift parameters 122 may be mapped to one entry in the mapping table 204. Referring to the example of FIG. 1A, entry E3 in FIG. 2 may store gain control parameter 1321 and phase control parameter 1341, and entry E1 in FIG. 2 may store gain control parameter 1322. N and phase control parameters 134 N In response to the decoder 202 mapping all of the phase shift parameters 122 to entries in the mapping table 204, the mapper 130 can load or distribute the control settings in the mapped entries to the front-end circuit 108. For example, the mapper 130 can load or distribute the control settings in the mapped entries to the front-end circuit 108. k , and E1 to front-end circuits 1081, 1082, and 108 N In one example, a latch may be connected between the mapper 130 and each of the front-end circuits 108 (e.g., a total of N latches for each beamforming IC 102). For example, latches 2061, 2062, and 2063 may be connected between the mapper 130 and each of the front-end circuits 108 (e.g., a total of N latches for each beamforming IC 102). N The mapper 130 and the front-end circuits 1081, 1082, and 108 NA latch connected between the mapper 130 and the front-end circuit 108 can facilitate loading of entries from the mapper 130 to the front-end circuit 108. For example, entries E3, E k , and E1 are sequentially (e.g., one at a time) connected to the front-end circuits 1081, 1082, 108 N Thus, in the example shown in FIG. 2, a first load operation can store entry E3 in latch 2061, and a second load operation can store entry E k can be stored in latch 2062, and the Nth load operation loads entry E1 into latch 206 N In response to storing the N entries in the N latches, the front-end circuit 108 can realize the phase and gain parameters necessary to generate the desired beam 104. Different combinations of entries in the mapping table 204 can result in different beam directions. It should be noted that the mapping table 204 shared by the front-end circuits 108 can occupy a relatively small amount of space compared to conventional approaches that may allocate one beam table to each front-end circuit.

[0024] In one example, the value of k and the entries E1 to E2 in the mapping table 204 are k The phase control parameters may depend on the desired implementation of system 100. For example, the value of k may be 72 such that mapping table 204 contains 72 rows or entries, entries E1 through E k The phase control parameters in entry E1 may be incremented in 5 degree intervals. For example, the phase control parameter in entry E1 may be 5 degrees, the phase control parameter in entry E2 may be 10 degrees, and so on. k The phase control parameter in may be 360 ​​degrees. If the phase shift parameter 122 of the ith antenna is 15 degrees, then the entry E3 with a phase control parameter of 15 degrees is Φ iIf the phase shift parameter 122 of the ith antenna is 50 degrees, the entry E 10 Φ i If the phase shift parameter 122 for the ith antenna is 13 degrees, the decoder 202 or mapper 130 may, for example, select the entry with the phase control parameter that may be closest to 13 (which in this example may be entry E3, which has a phase control parameter of 15 degrees). In one example, the value of k may be increased to increase the number of entries in the mapping table 204, thereby providing a more accurate mapping of the phase shift parameter 122 to the control settings of the mapping table 204.

[0025] 3 illustrates another exemplary mapper that can be used to perform the distributed calculation of phased array beamforming parameters in one embodiment. In the example shown in FIG. 3, mapper 130 includes decoder 302 and mapping tables 3041, 3042, ... 304. N In one example, the mapping tables 3041 to 3044 may include N mapping tables. N may be implemented as a look-up table that translates different values ​​of the phase shift parameter 122 into different control settings for a particular antenna. N The mapping tables 3041 through 3044 may be implemented as SRAM devices that store different values ​​of the phase shift parameter 122 and different control settings for a particular antenna. For example, the entries in the mapping table 3041 may translate different values ​​of Φ1 into different control settings for the antenna 1031. N Each of the entries E1 to E j The mapping tables 3041 to 3044 may contain j entries, denoted as j, where j is less than the number of possible beam directions that can be achieved by the multiple antennas 103. NEach entry in the mapping table 3041 may store control settings including phase control parameters and gain control parameters for a particular antenna. For example, the mapping table 3041 may include entries that store different values ​​of the gain control parameter 1321 and the phase control parameter 1341 for the antenna 1031.

[0026] The decoder 302 detects Φ1 to Φ N The phase shift parameters 122 are represented by the following mapping tables 3041 to 3044: N For example, the decoder 302 may include a circuit configured to map the input signal to a corresponding mapping table entry in the mapping table 304. N The phase shift parameter Φ is entered into one of the entries (e.g., shown by shading in Figure 3) of N The decoder 302 stores all the phase shift parameters 122 in the mapping tables 3041 to 3044. N In response to mapping to each mapping table entry, mapper 130 can load or distribute the control settings in the mapped entry to the corresponding front-end circuit 108. For example, mapper 130 can load the entries mapped to Φ1 in mapping table 3041 (e.g., the shaded entries in FIG. 3) into front-end circuit 1081. Different combinations of entries from each of mapping tables 3041-304N can result in different beam directions. N It should be noted that the beam tables 3041-3044 may be smaller than conventional beam tables that map one entry to one beam direction. Therefore, the embodiment shown in FIG. 3 can provide a smaller mapping table and also allows each front end to store a corresponding table 3041-3044. N , the beamforming IC 102 can compensate for potential element-to-element mismatches.

[0027] In one example, the value of j and the mapping tables 3041 to 304 N Entries E1~E j The phase control parameters in may depend on the desired implementation of system 100. For example, the value of j may be N may be 72, so that each of them contains 72 rows or entries, entries E1 to E j The phase control parameter in entry E1 may be incremented in 5 degree intervals. For example, the phase control parameter in entry E1 may be 5 degrees, the phase control parameter in entry E2 may be 10 degrees, and so on. j The phase control parameter in may be 360 ​​degrees. The phase shift parameter 122 of the ith antenna may be 15 degrees (e.g., Φ i = 15), the mapping table 304 has a phase control parameter of 15 degrees i Entry E3 of Φ i If the phase shift parameter 122 of the ith antenna is 50 degrees, the mapping table 304 may be mapped to i Entry E 10 Φ i If the phase shift parameter 122 for the ith antenna is 13 degrees, the decoder 302 or mapper 130 may, for example, find the mapping table 304 with the phase control parameter that is closest to 13. i In one example, the value of j is increased to select the entries in the mapping tables 3041 to 3044. N The number of entries in the mapping tables 3041 to 3042 can be increased to allow for more accurate mapping of the phase shift parameters 122. N can be provided for control settings.

[0028] The methods and systems described herein can use smaller mapping tables for large phased arrays, such as mapping tables with fewer entries than the number of possible beam directions that can be formed by the phased array. For example, the mapping tables shown in Figures 2 and 3 (e.g., 204 and 3041-304) can be used. N ) are mapped to one beam direction, instead of the ideal phase shift parameters (e.g., Φ i ) may be mapped to different values ​​of α and β. Thus, the size of the mapping table may not depend on the number of antenna elements or the number of beam directions. For example, the number of entries in the mapping table of system 100 may be less than the number of possible beam directions. Furthermore, the ideal phase shift parameters may be determined based on the physical location of the antenna, allowing the method and system to be implemented in phased array systems having different operating frequencies or phase shifter implementations. Furthermore, phase gradient parameters (e.g., α and β), which may require nonlinear calculations, can be distributed to off-chip devices that may have more computational resources than the beamforming IC. Thus, the values ​​of the phase gradient parameters may be broadcast to multiple beamforming chips using a single clock transaction, potentially reducing latency, power consumption, and input / output (I / O) operations between the off-chip device and the beamforming IC.

[0029] 4A-4C show example antenna patterns for implementation of distributed calculation of beamforming parameters for a phased array in one embodiment. In one example, the plurality of antennas 103 of FIGS. 1A-3 can have the antenna pattern 400 shown in FIG. 4A. The antenna pattern 400 can be an 8x8 uniform array with 64 antennas (e.g., N=64). Antenna 4021 can be located at position (-7,-7), i.e., x=-7 and y=-7, and antenna 402 64may be located at position (7,7), i.e., x=7 and y=7. These position values ​​can be used to calculate the phase shift parameters 122 (see FIG. 1A). Furthermore, these position values ​​can represent the position of each antenna among the multiple antennas 103 normalized to the resolution of the antenna pattern 400 or the antenna pitch. For example, the antenna pattern 400 may have a resolution of 0.5λ (λ is the wavelength of the desired beam 104), and the number of bits in the fractional representation of the antenna positions of the antenna pattern 400 may be 1. Because the exact positions of the antennas are used in the calculation, the calculation of the phase shift parameters 122 may not be affected by changes in resolution. However, because the antenna positions may change, changes in the number of bits in the fractional representation of the antenna positions may affect the calculation of the phase shift parameters 122.

[0030] For example, another antenna pattern 410 is shown in FIG. 4B. The antenna pattern 410 may be an 8×8 array with multiple 4×4 subarrays spaced at different intervals. The antenna pattern 410 may have a resolution of 0.25, and the number of bits in the fractional representation of the antenna positions of the antenna pattern 410 may be 2. Another antenna pattern 420 is shown in FIG. 4C. The antenna pattern 420 may be a circular array with a normalized radius of 4λ (λ is the wavelength of the desired beam 104). The antenna pitch of the antenna pattern 420 may also be variable. The antenna pattern 420 may have a resolution of 0.0625, and the number of bits in the fractional representation of the antenna positions of the antenna pattern 420 may be 4. The antenna pitch of the antenna pattern 410 may be variable. However, the calculation of the phase shift parameter 122 may not be affected by the variable pitch because any adjusted antenna positions may be used in the calculation.

[0031] FIG. 5 illustrates a flow diagram for calculating the variance of beamforming parameters for a phased array in one embodiment. Process 500 of FIG. 5 can be implemented using, for example, computer system 100 described above. The exemplary process may include one or more operations, actions, or functions as illustrated by one or more of blocks 502, 504, 506, or 508, or combinations thereof. While illustrated as separate blocks, various blocks may be divided into additional blocks, combined into fewer blocks, eliminated, performed in a different order, or performed in parallel, depending on the desired implementation.

[0032] Process 500 can begin at block 502, where a first circuit in the system can convert a desired beam direction of a desired beam into at least one phase gradient parameter. The phased array can include multiple antennas connected to multiple front-end circuits of a beamforming circuit, each antenna connected to a respective front-end circuit. In one example, the first circuit can convert the desired beam direction into a first phase gradient parameter based on a beam angle of the desired beam, a wavelength of the desired beam, and a minimum unit spacing between the multiple antennas in a first direction in a two-dimensional plane. The first circuit can further convert the desired beam direction into a second phase gradient parameter based on the beam angle of the desired beam, the wavelength of the desired beam, and a spacing between the multiple antennas in a second direction in the two-dimensional plane.

[0033] Process 500 may proceed from block 502 to block 504. Block 504 may include blocks 506 and 508, with blocks 506 and 508 being performed for each antenna of the plurality of antennas. In block 506, a second circuit may determine a phase shift parameter for the antenna based on at least one phase gradient parameter and the physical location of the antenna. Process 500 may proceed from block 506 to block 508. In block 508, the second circuit may map the determined phase shift parameter for the antenna to a control setting for a front-end circuit connected to the antenna. In one example, the second circuit may map the phase shift parameter for the antenna to a control setting using a mapping table that stores different values ​​of the phase control parameter for multiple front-end circuits. Combinations of the phase control parameters from the mapping table may be used to configure the multiple front-end circuits to cause the phased array to form desired beams having desired beam directions. In one example, the mapping table may be stored in a memory device connected to the multiple front-end circuits. In one example, the number of entries in the mapping table may be less than the number of possible beam directions of the beams formed by the phased array. In one example, latches or memory registers coupled to each front end are used to store the front end control settings determined by the mapper.

[0034] In another example, the second circuit can map antenna phase shift parameters to control settings using multiple mapping tables that store different values ​​of phase control parameters for multiple front-end circuits. Combinations of phase control parameters from the multiple mapping tables can be used to configure the multiple front-end circuits to cause the phased array to form desired beams having desired beam directions, where each phase control parameter in the combinations of phase control parameters can be from a corresponding mapping table. In one example, the multiple mapping tables can be stored in multiple memory devices connected to the multiple front-end circuits. In one example, the number of entries in each mapping table in the multiple mapping tables can be less than the number of possible beam directions of the beams formed by the phased array.

[0035] The flowcharts and block diagrams in the figures illustrate the architecture, functionality, and operation of possible implementations of systems, methods, and computer program products according to various embodiments of the present invention. In this regard, each block in a flowchart or block diagram may represent a module, segment, or portion of instructions, which constitute one or more executable instructions for implementing specified logical functions. In some alternative implementations, the functions shown in the blocks may occur out of the order shown in the figures. For example, two blocks shown in succession may, in fact, be executed substantially concurrently, or the blocks may sometimes be executed in the reverse order, depending on the functionality involved. It should also be noted that each block of the block diagrams and / or flowcharts, and combinations of blocks in the block diagrams and / or flowcharts, may be implemented by dedicated hardware-based systems that perform the specified functions or acts or execute a combination of dedicated hardware and computer instructions.

[0036] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the singular forms "a," "an," and "the" are intended to include the plural forms as well, unless the context clearly dictates otherwise. It will be further understood that the terms "comprises" and / or "comprising," when used herein, specify the presence of stated features, integers, steps, operations, elements, or components, or combinations thereof, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components, or groups thereof, or combinations thereof.

[0037] In addition to all means or steps in the following claims, corresponding structure, materials, acts, and equivalents of functional elements, if any, are intended to include any structure, material, or act for performing a function in combination with other claimed elements as specifically claimed. The description of the present invention has been presented for purposes of illustration and description, but is not intended to be exhaustive or to limit the invention to the form disclosed. Many modifications and variations will be apparent to those skilled in the art without departing from the scope of the invention. The present embodiments were chosen and described in order to best explain the principles and practical application of the invention and to enable others skilled in the art to understand the invention in various embodiments with various modifications as suited to the particular uses contemplated.

Claims

1. 1. A method for operating a phased array, comprising: converting a desired beam direction of a desired beam into at least one phase gradient parameter, wherein the phased array comprises a plurality of antennas connected to a plurality of front-end circuits of a beamforming circuit, each antenna connected to a respective front-end circuit, and the phase gradient parameter is dependent on a beam angle of the desired beam, a wavelength of the desired beam, and a minimum unit spacing between the plurality of antennas; determining, by the beamforming circuitry, a plurality of phase shift parameters for the plurality of antennas based on the at least one phase gradient parameter and physical locations of the plurality of antennas, the plurality of phase shift parameters being different from the at least one phase gradient parameter, and the antenna phase shift parameters representing phase shifts of the antennas required to contribute to forming the desired beam; mapping, by the beamforming circuitry, the plurality of phase shift parameters to a plurality of control settings stored in the plurality of front-end circuits, the control settings including phase shifter settings and gain control circuit settings, wherein the phase shifter settings of an antenna cause the antenna to perform a phase shift according to the phase shifter settings; distributing, by the beamforming circuitry, the plurality of control settings mapped for the plurality of phase shift parameters to the plurality of front-end circuits; configuring the phased array with the plurality of front-end circuits using the plurality of control settings mapped for the plurality of phase-shift parameters to cause the phased array to form the desired beam having the desired beam direction; A method comprising:

2. mapping the plurality of phase shift parameters of the plurality of antennas to the plurality of control settings includes using a mapping table that stores different values ​​of phase shifter settings of the plurality of front-end circuits; configuring the plurality of front-end circuits using a combination of phase shifter settings from the mapping table to cause the phased array to form the desired beam having the desired beam direction. The method of claim 1.

3. 3. The method of claim 2, wherein the mapping table is stored in a memory device connected to the plurality of front-end circuits.

4. mapping the plurality of phase shift parameters of the plurality of antennas to the plurality of control settings includes using a plurality of mapping tables, each mapping table storing a different value of a phase shifter setting of the plurality of front-end circuits; further comprising configuring the plurality of front-end circuits using combinations of phase shifter settings from the plurality of mapping tables to cause the phased array to form the desired beam having the desired beam direction, wherein each phase shifter setting among the combinations of phase shifter settings is from a corresponding mapping table. The method of claim 1.

5. 5. The method of claim 4, wherein the plurality of mapping tables are stored in a plurality of memory devices connected to the plurality of front-end circuits.

6. converting the desired beam direction to the at least one phase gradient parameter; converting the desired beam direction into a first phase gradient parameter based on the beam angle of the desired beam, the wavelength of the desired beam, and a minimum unit spacing between the plurality of antennas in a first direction in a two-dimensional plane; converting the desired beam direction into a second phase gradient parameter based on the beam angle of the desired beam, the wavelength of the desired beam, and a minimum unit spacing between the plurality of antennas in a second direction in the two-dimensional plane; The method of claim 1 , comprising:

7. 2. The method of claim 1, wherein mapping the plurality of phase shift parameters of the plurality of antennas to the control settings comprises using at least one mapping table that stores different values ​​of phase shifter settings of the plurality of front-end circuits, and wherein a number of respective entries of the at least one mapping table is less than a number of possible beam directions of beams formed by the phased array.

8. A processor; a beamforming circuit coupled to the processor, the beamforming circuit including a plurality of front-end circuits; a phased array including a plurality of antennas connected to the plurality of front-end circuits of the beamforming circuit; Equipped with the processor: converting a desired beam direction of a desired beam into at least one phase gradient parameter, the phase gradient parameter being dependent on a beam angle of the desired beam, a wavelength of the desired beam, and a minimum unit spacing between the plurality of antennas; transmitting the at least one phase gradient parameter to the beamforming circuitry; It is configured as follows: The beamforming circuitry receiving the at least one phase gradient parameter; determining a plurality of phase shift parameters for the plurality of antennas based on the at least one phase gradient parameter and the physical locations of the plurality of antennas, the plurality of phase shift parameters being different from the at least one phase gradient parameter, and the antenna phase shift parameters representing phase shifts of the antennas required to contribute to forming the desired beam; mapping the plurality of phase shift parameters to a plurality of control settings of the plurality of front-end circuits, the control settings including phase shifter settings and gain control circuit settings, and a phase shifter setting of an antenna causing the antenna to perform a phase shift according to the phase shifter setting; distributing the plurality of control settings mapped for the plurality of phase shift parameters to the plurality of front-end circuits; It is configured as follows: the plurality of front-end circuits controlling the phased array using the plurality of control settings mapped for the plurality of phase shift parameters to cause the phased array to form the desired beam having the desired beam direction; It is configured as follows: system.

9. the beamforming circuitry comprises a memory device coupled to the plurality of front-end circuits; the memory device is configured to store a mapping table storing different values ​​of phase shifter settings of the plurality of front-end circuits; The system of claim 8.

10. The beamforming circuitry configuring the plurality of front-end circuits using combinations of phase shifter settings from the mapping table to cause the phased array to form the desired beam having the desired beam direction; The system of claim 9 further configured to:

11. the beamforming circuitry comprises a plurality of memory devices connected to the plurality of front-end circuits, each memory device connected to one front-end circuit; each of the plurality of memory devices is configured to store a mapping table storing different values ​​of phase shifter settings of an associated front-end circuit; The system of claim 8.

12. 12. The system of claim 11, wherein the beamforming circuitry is further configured to configure the plurality of front-end circuits using combinations of phase-shifter settings from mapping tables connected to the plurality of memory devices, each phase-shifter setting of the combinations of phase-shifter settings being from a corresponding mapping table.

13. The system of claim 8 , further comprising a memory device configured to store the physical locations of the plurality of antennas.

14. 9. The system of claim 8, wherein the beamforming circuitry comprises at least one memory device configured to store at least one mapping table that stores different values ​​of phase shifter settings for the plurality of front-end circuits, the at least one memory device being connected to the plurality of front-end circuits, and wherein a number of entries in each of the at least one mapping table is less than a number of possible beam directions of beams formed by the phased array.

15. A plurality of antennas; a beamforming circuit including a plurality of front-end circuits connected to the plurality of antennas, the beamforming circuit being configured to receive at least one phase gradient parameter from a device and physical locations of the plurality of antennas, the at least one phase gradient parameter being based on a beam angle of a desired beam, a wavelength of the desired beam, and a minimum unit spacing between the plurality of antennas; Equipped with The beamforming circuitry determining a plurality of phase shift parameters for the plurality of antennas based on the at least one phase gradient parameter and the physical locations of the plurality of antennas, the plurality of phase shift parameters being different from the at least one phase gradient parameter, and the antenna phase shift parameters representing phase shifts of the antennas required to contribute to forming the desired beam; mapping the plurality of phase shift parameters to a plurality of control settings of the plurality of front-end circuits, the control settings including phase shifter settings and gain control circuit settings, and a phase shifter setting of an antenna causing the antenna to perform a phase shift according to the phase shifter setting; distributing the plurality of control settings mapped for the plurality of phase shift parameters to the plurality of front-end circuits; It is configured as follows: the plurality of front-end circuits controlling the plurality of antennas using the plurality of control settings mapped to the plurality of phase shift parameters to cause the plurality of antennas to form the desired beams having the desired beam directions; It is configured as follows: Device.

16. the beamforming circuitry comprises a memory device coupled to the plurality of front-end circuits; the memory device is configured to store a mapping table storing different values ​​of phase shifter settings of the plurality of front-end circuits; 16. The apparatus of claim 15.

17. The beamforming circuitry configuring the plurality of front-end circuits using combinations of phase shifter settings from the mapping table to form the desired beam having the desired beam direction; 17. The apparatus of claim 16, configured to:

18. the beamforming circuitry comprises a plurality of memory devices connected to the plurality of front-end circuits, each memory device connected to one front-end circuit; each of the plurality of memory devices is configured to store a mapping table storing different values ​​of phase shifter settings of an associated front-end circuit; 16. The apparatus of claim 15.

19. 20. The apparatus of claim 18, wherein the beamforming circuitry is configured to configure the plurality of front-end circuits using combinations of phase-shifter settings from mapping tables connected to the plurality of memory devices, each phase-shifter setting of the combinations of phase-shifter settings being from a corresponding mapping table.

20. 16. The apparatus of claim 15, wherein the beamforming circuitry comprises at least one memory device configured to store at least one mapping table that stores different values ​​of phase shifter settings of the plurality of front-end circuits, the at least one memory device being connected to the plurality of front-end circuits, and wherein the number of entries in each of the at least one mapping table is less than the number of possible beam directions of beams formed by the beamforming circuitry.

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