Communications device and method for performing sensing

Abstract

This disclosure provides a communication apparatus and method for performing sensing. A communication apparatus for performing sensing includes at least one storage device and at least one processing circuit. The at least one processing circuit executes the following instructions stored in the at least one storage device: transmitting a plurality of first packets; receiving a plurality of second packets; determining a plurality of channel frequency responses of the plurality of second packets based on the plurality of first packets; converting the plurality of channel frequency responses into a plurality of channel impulse responses; determining a distance to a target object based on a channel impulse response; compensating the plurality of channel impulse responses to generate a plurality of compensated channel impulse responses; converting the plurality of compensated channel impulse responses into a plurality of compensated channel frequency responses; and determining a velocity of the target object based on the plurality of compensated channel frequency responses.

Description

Technical Field

[0001] The present invention relates to a communication apparatus and method for a wireless communication system, and more particularly to a communication apparatus and method for performing sensing. Background Technology

[0002] Current wireless communication systems primarily employ two sensing methods: bistatic and monostatic. In bistatic mode, signal transmission and reception are performed by two separate communication devices, while in monostatic mode, both are performed by the same communication device. Compared to monostatic mode, bistatic mode exhibits lower sensing accuracy due to differences between the transmitting and receiving communication devices (e.g., initial phase, transmission power, frequency offset, and time synchronization). In current wireless communication systems, monostatic communication devices perform sensing by transmitting continuous signals. However, how monostatic communication devices perform sensing by transmitting discontinuous signals remains unknown. Summary of the Invention

[0003] This invention discloses a communication device for performing sensing, comprising: at least one storage device configured to store instructions; and at least one processing circuit coupled to the at least one storage device and configured to execute the following instructions stored in the at least one storage device: transmitting a plurality of first packets; receiving a plurality of second packets corresponding to the plurality of first packets; determining a plurality of channel frequency responses (CFRs) based on the plurality of first packets and the plurality of second packets; converting the plurality of channel frequency responses into a plurality of channel impulse responses (CIRs); determining at least one distance of a target object based on a channel impulse response of the plurality of channel impulse responses; compensating the plurality of channel impulse responses to generate a plurality of compensated channel impulse responses; converting the plurality of compensated channel impulse responses into a plurality of compensated channel frequency responses; and determining at least one velocity of the target object based on the plurality of compensated channel frequency responses.

[0004] This invention also discloses a method for performing sensing, comprising: transmitting a plurality of first packets; receiving a plurality of second packets corresponding to the plurality of first packets; determining a plurality of channel frequency responses (CFRs) based on the plurality of first packets and the plurality of second packets; converting the plurality of channel frequency responses into a plurality of channel impulse responses (CIRs); determining at least one distance of a target object based on one of the plurality of channel impulse responses; compensating the plurality of channel impulse responses to generate a plurality of compensated channel impulse responses; converting the plurality of compensated channel impulse responses into a plurality of compensated channel frequency responses; and determining at least one velocity of the target object based on the plurality of compensated channel frequency responses.

[0005] As described above, the communication device obtains a channel impulse response by transmitting and receiving discontinuous packets. The communication device then compensates for the channel impulse response to eliminate initial phase, time delay, and circuit / hardware mismatches, thereby improving sensing accuracy. Based on the compensated channel impulse response, the communication device determines information about the target object (e.g., distance and / or speed). Attached Figure Description

[0006] Figure 1 This is a schematic diagram of a communication device according to Embodiment 1 of the present invention.

[0007] Figure 2 This is a flowchart of a first embodiment of the present invention.

[0008] Figure 3 This is a schematic diagram of the channel impulse response according to Embodiment 1 of the present invention.

[0009] Symbol Explanation

[0010] 10: Communication device

[0011] 100: At least one processing circuit

[0012] 110: At least one storage device

[0013] 114: Program Code

[0014] 120: At least one communication interface device

[0015] 20: Process

[0016] S200, S202, S204, S206, S208, S210, S212, S214, S216, S218: Steps , , , , Time delay Detailed Implementation

[0017] Figure 1 This is a schematic diagram of a communication device 10 according to an embodiment of the present invention. The communication device 10 may include at least one processing circuit 100, at least one storage device 110, and at least one communication interface device 120. The at least one processing circuit 100 may be a microprocessor or an application-specific integrated circuit (ASIC). The at least one storage device 110 may be any data storage device used to store program code 114. The at least one processing circuit 100 can read and execute the program code 114 through the at least one storage device 110. For example, at least one storage device 110 may be a Subscriber Identity Module (SIM), Read-Only Memory (ROM), Flash Memory, Random-Access Memory (RAM), Compact Disc ROM (CD-ROM), Digital Versatile Disc-ROM (DVD-ROM), Blu-ray Disc-ROM (BD-ROM), Magnetic Tape, Hard Disk, Optical Data Storage Device, Non-volatile Storage Device, Non-transitory Computer-readable Medium (e.g., tangible media), etc., but is not limited to these. At least one communication interface device 120 may include at least one transmitter (e.g., a transmitting antenna) and at least one receiver (e.g., a receiving antenna), which are used to transmit and receive signals (e.g., data, information and / or packets) respectively, based on the processing results of at least one processing circuit 100.

[0018] The communication device 10 can be applied to a wireless communication system. The wireless communication system may include, but is not limited to, wireless local area networks (WLANs) (e.g., Wi-Fi), personal area networks (PANs) (e.g., Bluetooth (BT)), digital video broadcasting (DVB) systems, Long Term Evolution (LTE) systems, LTE-advanced (LTE-A) systems, or 5th generation wireless communication (5G) systems.

[0019] Figure 2 This is a flowchart of process 20 according to an embodiment of the present invention. Process 20 is used for a monostatic communication device (e.g., Figure 1 The communication device 10) is used to perform sensing. Process 20 can be compiled into program code 114, which includes the following steps: Step S200: Begin.

[0020] Step S202: Transmit multiple first packets.

[0021] Step S204: Receive a plurality of second packets corresponding to the plurality of first packets.

[0022] Step S206: Determine multiple channel frequency responses (CFRs) based on the multiple first groups and the multiple second groups respectively.

[0023] Step S208: Convert the multiple channel frequency responses into multiple channel impulse responses (CIRs).

[0024] Step S210: Determine at least one distance of a target object based on one of the multiple channel impulse responses.

[0025] Step S212: Compensate the plurality of channel impulse responses to generate a plurality of compensated channel impulse responses.

[0026] Step S214: Convert the multiple compensated channel impulse responses into multiple compensated channel frequency responses respectively.

[0027] Step S216: Determine at least one velocity of the target object based on the multiple compensated channel frequency responses.

[0028] Step S218: End.

[0029] In process 20, the multiple first packets are multiple non-contiguous packets. By compensating for and analyzing the channel response, the communication device obtains information about the target object (e.g., distance and / or velocity at different time delays).

[0030] There are many ways to implement process 20, not limited to those described above. The following examples can be used for process 20.

[0031] In one embodiment, the plurality of second packets are multiple non-contiguous packets. In another embodiment, the plurality of second packets are packets received by the communication device after the plurality of first packets have passed through multiple transmission paths (e.g., transmission paths reflected from a target object, transmission paths within the communication device's internal circuitry / hardware, and / or direct-line paths between the transmitter and receiver). In one embodiment, the plurality of first packets and the plurality of second packets are time-domain signals. In one embodiment, the communication device converts multiple channel frequency responses into multiple channel impulse responses using an inverse fast Fourier transform (IFFT).

[0032] In one embodiment, the channel impulse response includes a plurality of first pulses. In one embodiment, step S210 includes at least one of the following steps: selecting a plurality of second pulses from the plurality of first pulses of the channel impulse response, wherein the energy (or power) of each of the plurality of second pulses is greater than a threshold; selecting a line-of-sight (LOS) pulse from the plurality of second pulses; selecting at least one pulse from the plurality of second pulses; calculating at least one relative time delay based on at least one time delay corresponding to the at least one pulse and a line-of-sight time delay corresponding to the line-of-sight pulse; and calculating at least one distance to the target object based on at least one of the at least one relative time delay, the line-of-sight time delay, and the speed of light. In one embodiment, the line-of-sight pulse has the maximum energy (or maximum power) among the plurality of second pulses. In one embodiment, at least one pulse is later than the line-of-sight pulse (e.g., in the time domain). In one embodiment, at least one distance is the distance between the communication device and the target object under at least one time delay. In one embodiment, the number of the plurality of second pulses is not greater than the number of the plurality of first pulses. In one embodiment, the communication device dynamically adjusts the threshold.

[0033] In one embodiment, step S212 includes at least one of the following steps: determining multiple line-of-sight pulses for multiple channel impulse responses; calculating multiple phase compensation parameters and multiple amplitude compensation parameters based on the multiple line-of-sight pulses; and compensating the multiple channel impulse responses based on the multiple phase compensation parameters and multiple amplitude compensation parameters to generate multiple compensated channel impulse responses. In one embodiment, the multiple line-of-sight pulses correspond to multiple channel impulse responses. That is, based on the line-of-sight pulses, the communication device performs compensation on other pulses of the channel impulse response to eliminate mismatches in the communication device's circuitry or hardware.

[0034] In one embodiment, step S212 includes at least one of the following steps: calculating multiple time differences among multiple first packets (or multiple second packets) based on time intervals; calculating multiple phase differences among the multiple first packets (or multiple second packets) based on the multiple time differences (e.g., by interpolation); and compensating multiple channel impulse responses based on the multiple phase differences to generate multiple compensated channel impulse responses. In one embodiment, the time interval is the time interval between two adjacent packets in the multiple first packets (or multiple second packets) that the communication device expects to transmit (or receive). That is, the communication device calculates the time difference for transmitting the first packets (or receiving the second packets) to compensate for the phase change caused by the time difference.

[0035] In one embodiment, the communication device converts multiple compensated channel impulse responses into multiple compensated channel frequency responses using a Fast Fourier Transform (FFT). In one embodiment, the number of the multiple first groups is the size of the FFT. In another embodiment, the number of the multiple second groups is the size of the FFT.

[0036] In one embodiment, step S216 includes at least one of the following steps: calculating a Doppler shift based on a plurality of compensated channel frequency responses; and calculating at least one velocity of the target object based on at least one of the Doppler shift, the speed of light, and the subcarrier frequency. In one embodiment, the at least one velocity is the velocity of the target object under at least one time delay.

[0037] The following first embodiment illustrates how a communication device senses the distance to a target object. First, signals are transmitted in the frequency domain. It consists of multiple subcarriers. Through an inverse fast Fourier transform, the communication device converts the frequency-domain transmission signal into a time-domain transmission signal (e.g., a first packet of multiple first packets), and transmits the time-domain transmission signal. Time-domain transmission signal This can be represented by the equation (Equation 1): (Equation 1) in It is the first Frequency domain symbols of each subcarrier, It is the subcarrier spacing, It is the number of subcarriers, and It is a time-domain transmission signal The length of the signal transmitted in the time domain. go through After one transmission path, the communication device receives the time-domain received signal. (For example, a second group of multiple second groups). Time-domain received signal. This can be represented by equation (Equation 2): (Equation 2) in It is the channel impulse response, and It is additive white Gaussian noise (AWGN). The received signal in the time domain is obtained through Fourier transform. Converted into frequency domain received signal as follows: (Equation 3) Transmitting signals in a known frequency domain In this case, the communication device can obtain the channel frequency response through equation (Equation 3). (For example, the frequency response of a single channel among multiple channel frequency responses). Channel frequency response This can be represented by equation (Equation 4): (Equation 4) Next, through inverse Fourier transform, the channel frequency response is obtained. Converted into channel impulse response (For example, the single-channel impulse response of multiple channel impulse responses) is as follows: (Equation 5) in It is an index of the transmission path. , It is the first The amplitude of each transmission path, and It is the first Time delay of each transmission path. Channel impulse response. For reference Figure 3 However, this is not the only one. Figure 3 In the diagram, the horizontal axis represents the time delay of the transmission path, and the vertical axis represents the amplitude of the transmission path. Channel impulse response. Depend on Composed of pulses, Each pulse corresponds to One transmission path. The communication device calculates the channel impulse response. The energy of each pulse is shown in equation (6): (Equation 6) in Reflected in time delay The next The pulse (or the first pulse) Energy of each transmission path From the channel impulse response In the pulse (e.g., multiple first pulses), the communication device selects pulses with energy greater than a threshold (e.g., multiple second pulses) to perform subsequent operations. That is, the communication device ignores pulses with energy not greater than the threshold.

[0038] For ease of subsequent calculations, this embodiment assumes the channel impulse response. Each pulse in the process has an energy greater than a threshold. From the pulses with energy greater than the threshold, the communication device selects the pulse with the highest energy as the line-of-sight pulse. The line-of-sight pulse corresponds to the straight transmission path from the transmitter to the receiver in the communication device, which can be referenced... Figure 3 Corresponding to time delay The pulse preceding the direct pulse corresponds to a transmission path with internal leakage (e.g., leakage from the transmitter to the receiver in the communication device), which can be referenced. Figure 3 Corresponding to time delay ~ The pulse. A pulse later than the direct-view pulse (e.g., at least one pulse) corresponds to the transmission path of the signal reflected from the target object, which can be referenced. Figure 3 Corresponding to time delay ~ The pulse. Pulses earlier than the direct-view pulse are irrelevant to the target object and can therefore be ignored.

[0039] Next, with a time delay corresponding to the direct-viewing pulse Based on a reference (e.g., direct-view time delay), the communication device calculates the relative time delay. As shown in equation (7): (Equation 7) in According to the speed of light Due to the time factor, the communication device calculates the relative distance. and distance compensation parameters As shown in equations (8) and (9): (Equation 8) (Equation 9) in ,as well as (meters / second). Based on relative distance. and distance compensation parameters The communication device obtains the distance .distance This can be represented by equation (Equation 10): (Equation 10) Where the distance It is a time delay The distance between the communication device and the target object, and .

[0040] The following second embodiment illustrates how a communication device senses the speed of a target object. In the first embodiment, the communication device transmits a time-domain transmission signal. and receiving a time-domain received signal In the second embodiment, the communication device transmits... Time-domain transmission signal and receiving Time-domain received signal ,in . Time-domain transmission signal It is a discontinuous signal, meaning there is a time interval between two adjacent time-domain transmitted signals from a communication device. Then, in receiving... Each frequency domain received signal Then, the communication device will receive N time-domain signals. Convert to Each frequency domain received signal , can obtain Channel impulse response Frequency domain received signal and channel impulse response Refer to the aforementioned equations (Equations 1) to (Equations 5), which will not be repeated here. The communication device determines... Channel impulse response of A direct-looking pulse. According to... A direct-line pulse, the communication device calculates phase compensation parameters. and amplitude compensation parameters As shown in equations (11) and (12): (Equation 11) (Equation 12) in It is the first A direct-looking pulse, It corresponds to the first The time delay of the direct-looking pulse. Based on the phase compensation parameters. and amplitude compensation parameters Communication devices Channel impulse response Execute the first compensation to generate One compensated channel impulse response (For example, multiple compensated channel impulse responses). Compensated channel impulse responses This can be represented by equation (Equation 13): (Equation 13) in .

[0041] Assume the first Time-domain transmission signal Compared to the previous time-domain transmitted signal The time interval is The time interval is This can be represented by equation (Equation 14): (Equation 14) in It is the expected time interval of the communication device, and It refers to time differences (e.g., multiple time differences). Based on time differences... The communication device calculates the phase difference. (For example, multiple phase differences) are as follows: (Equation 15) Based on phase difference The communication device's response to the compensated channel impulse. A second compensation is performed to generate a compensated channel impulse response. (For example, multiple compensated channel impulse responses). It should be noted that the compensation method described in equations (11) to (13) and their related explanations is based on the direct-line impulse. Based on the reference, other pulses in the communication device's response to the channel impulse. ( Compensation is performed to eliminate mismatches in the circuitry or hardware of the communication device. The compensation method described in Equations (14) and (15) and their related explanations involves the communication device calculating the time difference of the transmitted signal in the time domain and compensating for the phase change caused by the time difference through interpolation. Both of these compensation methods can improve sensing accuracy.

[0042] Next, the communication device responds to the compensated channel impulse. Perform a Fast Fourier Transform to obtain the compensated channel frequency response. (e.g., channel frequency response with multiple compensations) and Doppler shift Compensated channel frequency response This can be represented by equation (Equation 16): (Equation 16) The communication device calculates the velocity of the target object based on equations (17) and (18).

[0043] (Equation 17) (Equation 18) The term "determine" as described in the above operations can be replaced with "compute," "calculate," "obtain," "generate," "output," "use," "choose / select," "decide," or "is configured to." The term "according to" in the above operations can be replaced with "in response to." The term "corresponding to" used in the above description can be replaced with "of" or "associated with." The term "via" used in the above description can be replaced with "on," "in," or "at."

[0044] Those skilled in the art can combine, modify, or change the above-described embodiments in accordance with the spirit of the present invention, but are not limited thereto. The foregoing statements, steps, and / or processes (including suggested steps) can be implemented by a device, which can be hardware, software, firmware (a combination of hardware device and computer instructions and data, where the computer instructions and data are read-only software on the hardware device), electronic system, or a combination of the above devices, wherein the device can be a communication device.

[0045] The hardware may be analog microcomputer circuitry, digital microcomputer circuitry, and / or hybrid microcomputer circuitry. For example, the hardware may be an application-specific integrated circuit, a field-programmable gate array (FPGA), a programmable logic device, coupled hardware components, or a combination of the above. In other embodiments, the hardware may include a general-purpose processor, a microprocessor, a controller, a digital signal processor (DSP), or a combination of the above.

[0046] Software can be a combination of program code, instructions, and / or functions, stored (e.g., in a storage unit, such as a computer-readable medium). For example, a computer-readable medium can be a user identification module, read-only memory, flash memory, random access memory, optical disc read-only memory (CD-ROM / DVD-ROM / BD-ROM), magnetic tape, hard disk, optical data storage device, non-volatile storage unit, or a combination of the above. The computer-readable medium (such as a storage unit) can be coupled to at least one processor (e.g., a processor integrated with the computer-readable medium) in a built-in manner or externally coupled to at least one processor (e.g., a processor independent of the computer-readable medium). The at least one processor may include (e.g., be configured to) one or more modules to execute the software stored in the computer-readable medium. The combination of program code, instructions, and / or functions can cause at least one processor, one or more modules, hardware, and / or electronic systems to perform relevant steps.

[0047] Electronic systems can be system-on-chip (SoC), system-in-package (SiP), computer-on-module (CoM), computer programmable products, devices, mobile phones, notebook computers, tablet computers, e-books, portable computer systems, and communication devices.

[0048] As described above, the communication device obtains a channel impulse response by transmitting and receiving discontinuous packets. The communication device then compensates for the channel impulse response to eliminate initial phase, time delay, and circuit / hardware mismatches, thereby improving sensing accuracy. Based on the compensated channel impulse response, the communication device determines information about the target object (e.g., distance and / or speed).

[0049] The foregoing outlines the features of several embodiments, enabling those skilled in the art to fully understand the various implementations of the invention. Those skilled in the art should recognize that the invention provides a basis for designing or modifying other processes and structures to achieve substantially the same functionality and / or results as the embodiments described above. Furthermore, such equivalent configurations do not depart from the spirit and scope of the invention, and various changes, substitutions, and modifications can be made without departing from that spirit and scope.

Claims

1. A communication device for performing sensing, wherein, The communication device includes: At least one storage device is configured to store instructions; and At least one processing circuit, coupled to the at least one storage device, is configured to execute the following instructions stored in the at least one storage device: Transmit multiple first packets; Receive a plurality of second packets corresponding to the plurality of first packets; Based on the plurality of first groups and the plurality of second groups, the frequency responses of the plurality of channels are determined respectively; The multiple channel frequency responses are respectively converted into multiple channel impulse responses; Based on one channel impulse response of the plurality of channel impulse responses, at least one distance of a target object is determined; The multiple channel impulse responses are compensated to generate multiple compensated channel impulse responses; The multiple compensated channel impulse responses are respectively converted into multiple compensated channel frequency responses; as well as Based on the multiple compensated channel frequency responses, at least one velocity of the target object is determined.

2. The communication device as claimed in claim 1, wherein the plurality of second packets are packets received by the communication device after the plurality of first packets have passed through multiple transmission paths.

3. The communication device of claim 1, wherein the communication device converts the plurality of channel frequency responses into the plurality of channel impulse responses respectively by means of an inverse fast Fourier transform.

4. The communication apparatus of claim 1, wherein the instruction for determining the at least one distance of the target object based on the channel impulse response of the plurality of channel impulse responses includes at least one of the following instructions: From a plurality of first pulses in the channel impulse response, a plurality of second pulses are selected, wherein the energy of each of the plurality of second pulses is greater than a threshold. Select a single-view pulse from the plurality of second pulses; Select at least one pulse from the plurality of second pulses; Calculate at least one relative time delay based on at least one time delay corresponding to the at least one pulse and one direct-viewing time delay corresponding to the direct-viewing pulse; as well as The at least one distance to the target object is calculated based on at least one of the at least one relative time delay, the direct viewing time delay, and the speed of light.

5. The communication apparatus of claim 1, wherein the instruction for compensating the plurality of channel impulse responses to generate the plurality of compensated channel impulse responses comprises at least one of the following instructions: Multiple line-of-sight pulses that determine the multiple channel impulse responses; Based on the multiple direct-view pulses, multiple phase compensation parameters and multiple amplitude compensation parameters are calculated respectively; as well as The multiple channel impulse responses are compensated according to the multiple phase compensation parameters and the multiple amplitude compensation parameters to generate the multiple compensated channel impulse responses.

6. The communication apparatus of claim 1, wherein the instruction for compensating the plurality of channel impulse responses to generate the plurality of compensated channel impulse responses comprises at least one of the following instructions: Calculate multiple time differences between the multiple first groups based on a time interval; Based on the multiple time differences, calculate the multiple phase differences of the multiple first groups respectively; as well as The multiple channel impulse responses are compensated according to the multiple phase differences to generate the multiple compensated channel impulse responses.

7. The communication apparatus of claim 1, wherein the communication apparatus converts the plurality of compensated channel impulse responses into the plurality of compensated channel frequency responses respectively via a fast Fourier transform.

8. The communication apparatus of claim 7, wherein the number of the plurality of second packets is a size of the fast Fourier transform.

9. The communication apparatus of claim 1, wherein the instruction for determining the at least one speed of the target object based on the plurality of compensated channel frequency responses comprises at least one of the following instructions: Calculate a Doppler offset based on the multiple compensated channel frequency responses; and The at least one velocity of the target object is calculated based on at least one of the Doppler shift, a speed of light, and a subcarrier frequency.

10. A method for performing sensing, comprising: Transmit multiple first packets; Receive a plurality of second packets corresponding to the plurality of first packets; Based on the plurality of first groups and the plurality of second groups, the frequency responses of the plurality of channels are determined respectively; The multiple channel frequency responses are respectively converted into multiple channel impulse responses; Based on one channel impulse response of the plurality of channel impulse responses, at least one distance of a target object is determined; The multiple channel impulse responses are compensated to generate multiple compensated channel impulse responses; The multiple compensated channel impulse responses are respectively converted into multiple compensated channel frequency responses; as well as Based on the multiple compensated channel frequency responses, at least one velocity of the target object is determined.

Images