Angle determination method and device

Abstract

The embodiment of the invention provides an angle determination method and device. The method comprises: a receiving device receiving a first multi-tone signal, the first multi-tone signal comprising N1 frequency points, N1 being an integer greater than or equal to 2; the receiving device performs phase measurement on the first multi-tone signal and obtains first phase values corresponding to k antennas of the first device at N1 frequency points; and the receiving device determines the angle of the signal of the first device according to the acquired first phase value. According to the method disclosed by the invention, rapid and high-precision angle measurement can be realized.

Description

[0001] Angle Determination Method and Apparatus Technical Field This application relates to the field of communications, and more specifically, to an angle determination method and apparatus. Background: Currently, positioning technology has a wide range of applications and enormous commercial value. The Global Navigation Satellite System (GNSS) can provide high-precision outdoor location information; WiFi positioning technology based on received signal strength indicator (RSSI) and Bluetooth positioning technology based on beacons can provide indoor location information. Currently, the Bluetooth Special Interest Group (Bluetooth SIG) supports Bluetooth protocols for angle of arrival (AoA) and angle of departure (AoD), improving indoor positioning accuracy by utilizing the directional information of Bluetooth low energy (BLE) signals. However, in real indoor environments, due to multipath reflections, phase differences fluctuate across channels, resulting in inconsistent angles calculated for different channels. Furthermore, due to limitations of the Bluetooth protocol, a single AoA / AoD angle measurement can only measure the phase information of a single frequency point, resulting in low final angle measurement accuracy and prolonged measurement time. Therefore, achieving fast and high-precision angle measurement is an urgent issue. SUMMARY OF THE INVENTION This application provides an angle determination method and apparatus that enable fast and high-precision angle measurement. In a first aspect, a method for determining an angle is provided. This method can be performed by a receiving device, or by a chip or circuit used in the receiving device, though this application is not limited thereto. For ease of description, the following description uses a receiving device as an example. The method includes: the receiving device receives a first multi-tone signal, the first multi-tone signal including N1 frequencies, where N1 is an integer greater than or equal to 2; the receiving device performs phase measurement on the first multi-tone signal, and obtains first phase values ​​corresponding to k antennas of the first device at the N1 frequencies, where k is an integer greater than or equal to 2; and the receiving device determines the angle of the signal of the first device based on the obtained first phase values. It should be understood that the first phase value can be viewed as a phase matrix having k columns and N1 rows, and the number of phase values ​​in the phase matrix can be greater than or equal to 2 and less than or equal to k times N1. Of course, interference from other signals may cause an antenna to fail to collect a phase value at a certain frequency point during the angle measurement of the first multi-tone signal, or a phase value error may be large. This application does not specifically limit this.According to the solution provided in this application, a multi-tone signal is received and phase measured, and the angle of a signal from a first device is determined based on the obtained measurement value. Compared to traditional single-tone signal phase measurement, using multi-tone signals to determine angles allows for faster phase acquisition, improves measurement efficiency, and enables rapid angle measurement. With reference to the first aspect, in certain implementations of the first aspect, when the first device is a receiving device, the angle of the signal from the first device is the angle of arrival of the receiving device; or, when the first device is a transmitting device, the angle of the signal from the first device is the angle of departure of the transmitting device. With reference to the first aspect, in certain implementations of the first aspect, the receiving device includes a radio frequency local oscillator (RF LO), and the receiving device downconverts the first radio frequency multi-tone signal to obtain a first baseband multi-tone signal, including: the receiving device mixing the first radio frequency multi-tone signal with a signal from the RF LO to obtain the first baseband multi-tone signal. It should be noted that in this implementation, the first RF multi-tone signal is the first multi-tone signal. For example, when determining the angle of arrival of a signal, the phase difference of the RF signal between two antennas needs to be measured. Given that the frequency of the RF signal changes rapidly, directly measuring the phase of the RF signal is difficult to implement. Therefore, in engineering implementation, the RF signal is down-converted to a lower-frequency baseband signal and then the phase of the baseband signal is measured to indirectly obtain the phase of the RF signal. The phase of the RF LO during the down-conversion process affects the phase value of the baseband signal. However, since the RF LO has the same effect on the phases of k antennas, the effect of the RF LO on the phases can be offset when calculating the phase differences between the k antennas. With reference to the first aspect, in certain implementations of the first aspect, a receiving device includes N1 digital LOs, each corresponding to N1 frequency points. The receiving device performs phase measurement on a first multi-tone signal and obtains first phase values ​​corresponding to k antennas of the first device at the N1 frequency points. This includes: the i-th digital LO of the receiving device performs digital down-conversion processing on the first multi-tone signal, performs IQ averaging processing on the digitally down-converted first multi-tone signal, and obtains the first phase values ​​corresponding to the k antennas of the first device at the i-th frequency point, where i is an integer greater than or equal to 1 and less than or equal to N1. In this implementation, the receiving device uses an IQ averaging method to obtain an average IQ of a signal at a certain frequency point at a certain antenna (the IQ values ​​of other frequencies are canceled out). Based on this average IQ, the phase value of the signal at the frequency point at the antenna can be calculated.Similarly, the phase value of the frequency signal at the other antenna can be obtained, and then the phase difference between the two antennas can be obtained for calculating the angle of arrival. It should be understood that the above process is applicable to the processing of all other frequency signals. With reference to the first aspect, in certain implementations of the first aspect, the receiving device determines the angle of the signal of the first device based on the obtained first phase value, including: the receiving device determines the angle of the signal of the first device based on the difference between the phase value corresponding to the first antenna at the i-th frequency and the phase value corresponding to the second antenna at the i-th frequency; wherein the first antenna and the second antenna are any two different antennas among the k antennas, and i is an integer greater than or equal to 1 and less than or equal to N1. With reference to the first aspect, in certain implementations of the first aspect, the frequency interval between any two adjacent frequency points among the N1 frequency points is the same. Optionally, the frequency interval between any two adjacent frequency points among the N1 frequency points of the first multi-tone signal may also be different, and this is not specifically limited. In conjunction with the first aspect, in certain implementations of the first aspect, the RF LO and multiple digital LOs of the receiving device remain in an unlocked state. That is, in this implementation, it is necessary to obtain phase values ​​corresponding to different frequencies for each antenna by switching antennas. To prevent LOs (including RF LO and digital LO) from introducing additional phases, during antenna switching, for example, when measuring the angle of arrival of a signal, the RF LO and multiple digital LOs of the receiving device continue to rotate. The multiple digital LOs and RF LOs of the transmitting device also continue to rotate, i.e., continuously transmitting multi-tone signals. In conjunction with the first aspect, in certain implementations of the first aspect, the receiving device receives a second multi-tone signal, which includes N2 frequencies, with M common frequencies between N2 and N1, where N2 is an integer greater than or equal to 2, and M is an integer greater than or equal to 1 and less than the minimum of N1 and N2. In combination with the first aspect, in certain implementations of the first aspect, the receiving device performs phase measurement on the second multi-tone signal, and obtains second phase values ​​corresponding to the k antennas of the first device at N2 frequency points; the receiving device determines the angle of the signal of the first device based on the obtained second phase values; or, the receiving device determines the angle of the signal of the first device based on the obtained first phase value and the second phase value.In conjunction with the first aspect, in certain implementations of the first aspect, the receiving device determines the angle of the signal of the first device based on the acquired first phase value and second phase value, including: the receiving device determines a phase compensation value based on the acquired first phase value and second phase value; the receiving device compensates the first phase value based on the phase compensation value; and the receiving device determines the angle of the signal of the first device based on the compensated first phase value and second phase value. Optionally, the receiving device determines the angle of the signal of the first device based on the acquired first phase value and second phase value, including: the receiving device determines a phase compensation value based on the acquired first phase value and second phase value; the receiving device compensates the second phase value based on the phase compensation value; and the receiving device determines the angle of the signal of the first device based on the compensated second phase value and the first phase value. Due to multipath reflection in actual signal measurements, different frequency points (or different channels) have different frequency responses. For example, the phase difference can vary significantly across channels, far exceeding the 3% variation in ideal conditions. That is, each path measured in a multipath environment will have a corresponding AoA / AoD, but the AoA / AoD corresponding to the line-of-sight (LOS) signal is the most accurate. The aforementioned phase value splicing can maximize frequency bandwidth, facilitating analysis of the flight time of multipath signals, and further determining the LOS and corresponding angle estimate. This implementation can improve angle measurement accuracy. It should be noted that when splicing the phase values ​​corresponding to the first and second multipath signals, the initial RF LO phases in the two measurements can be arbitrary. By using a common frequency point (or channel) method to calculate the difference between the initial RF LO phases of the two angle measurements, the initial RF LO phase values ​​can be compensated. Therefore, the effects of errors on the angle measurement results of the signals can be avoided or reduced. With reference to the first aspect, in certain implementations of the first aspect, the time interval between the transmission of the first and second multipath signals and the time interval between the reception of the first and second multitone signals are the same. Based on this implementation, the signal's time-of-flight offset can be maintained throughout the measurement process, avoiding the introduction of unnecessary errors. With reference to the first aspect, in certain implementations of the first aspect, the N1 digital LOs have the same initial phase when turned on, and the i-th digital LO has the same initial phase at a first moment and a second moment; the first moment is the moment when the first multi-tone signal is transmitted, and the second moment is the moment when the second multi-tone signal is transmitted; or the first moment is the moment when the first multi-tone signal is received, and the second moment is the moment when the second multi-tone signal is received.Based on this implementation, multiple digital LOs of a transmitting device are guaranteed to have the same initial phase when powered on, and the initial phase value of the same digital LO is also guaranteed to be the same during each angle measurement. Similarly, multiple digital LOs of a receiving device are guaranteed to have the same initial phase when powered on, and the initial phase value of the same digital LO is also guaranteed to be the same during each angle measurement. This avoids the introduction of additional phase errors and improves angle measurement accuracy. A second aspect provides an angle determination method. This method can be performed by a transmitting device, or by a chip or circuit used in the transmitting device, but this application is not limited to this. For ease of description, the following example uses a transmitting device as an example. The method includes: the transmitting device generates a first multi-tone signal, the first multi-tone signal including N1 frequency points, where N1 is an integer greater than or equal to 2; the transmitting device transmits the first multi-tone signal, the first multi-tone signal being used to determine the angle of a signal from the first device. According to the solution provided in this application, by transmitting the multi-tone signal, the receiving device performs phase measurement on the multi-tone signal and determines the angle of the signal from the first device based on the obtained measurement value. Compared to traditional single-tone signal phase measurement, using multi-tone signals to determine angles can quickly obtain phase values, improve measurement efficiency, and achieve rapid angle measurement. With reference to the second aspect, in certain implementations of the second aspect, when the first device is a receiving device, the angle of the signal from the first device is the angle of arrival of the receiving device; or, when the first device is a transmitting device, the angle of the signal from the first device is the angle of departure of the transmitting device. With reference to the second aspect, in certain implementations of the second aspect, the transmitting device includes N1 digital local oscillators (LOs), where the N1 digital LOs correspond to N1 frequency points. The transmitting device generates a first baseband multi-tone signal, including: the transmitting device adds signals from the N1 digital LOs to obtain the first baseband multi-tone signal. With reference to the second aspect, in certain implementations of the second aspect, the transmitting device also includes a radio frequency (RF) LO. The transmitting device up-converts the first baseband multi-tone signal to obtain a first radio frequency (RF) multi-tone signal, including: the transmitting device mixes the first baseband multi-tone signal with a signal from the RF LO to obtain the first RF multi-tone signal. With reference to the second aspect, in certain implementations of the second aspect, the frequency intervals between any two adjacent frequency points among the N1 frequency points are the same.With reference to the second aspect, in certain implementations of the second aspect, a transmitting device generates a second multi-tone signal, the second multi-tone signal including N2 frequency points, M common frequency points between the N2 frequency points and the N1 frequency point, where N2 is an integer greater than or equal to 2, and M is an integer greater than or equal to 1 and less than the minimum of N1 and N2. The transmitting device transmits the second multi-tone signal. With reference to the second aspect, in certain implementations of the second aspect, the time interval between the transmission times of the first multi-tone signal and the second multi-tone signal and the time interval between the reception times of the first multi-tone signal and the second multi-tone signal are the same. With reference to the second aspect, in certain implementations of the second aspect, the N1 digital LOs have the same initial phase when they are turned on, and the initial phase of the i-th digital LO at the first moment and the second moment is the same, where i is an integer greater than or equal to 1 and less than or equal to N1. The first moment is the transmission time of the first multi-tone signal, and the second moment is the transmission time of the second multi-tone signal. Alternatively, the first moment is the reception time of the first multi-tone signal, and the second moment is the reception time of the second multi-tone signal. In a third aspect, an angle determination apparatus is provided, comprising: a transceiver unit configured to receive a first multi-tone signal, the first multi-tone signal including N1 frequency points, where N1 is an integer greater than or equal to 2; a processing unit configured to perform phase measurement on the first multi-tone signal and obtain first phase values ​​corresponding to the N1 frequency points for k antennas of a first device; and the processing unit configured to determine the angle of the signal of the first device based on the obtained first phase values. The transceiver unit can perform the receiving and transmitting processing described in the first aspect, and the processing unit can also perform other processing in the first aspect except for the receiving and transmitting processing. In a fourth aspect, an angle determination apparatus is provided, comprising: a processing unit configured to generate a first multi-tone signal, the first multi-tone signal including N1 frequency points, where N1 is an integer greater than or equal to 2; and a transmitting unit configured to transmit the first multi-tone signal. The transceiver unit can perform the receiving and transmitting processing described in the second aspect, and the processing unit can also perform other processing in the second aspect except for the receiving and transmitting processing. In a fifth aspect, an angle determination apparatus is provided, comprising a processor and a memory. Optionally, the apparatus may also include a transceiver. The memory is used to store a computer program, and the processor is used to call and run the computer program stored in the memory and control the transceiver to send and receive signals, so that the angle measurement device performs the method of any possible implementation manner of the first aspect or the second aspect.In a sixth aspect, an angle determination device is provided, comprising a processor and a communication interface. The communication interface is configured to receive data and / or information and transmit the received data and / or information to the processor, which processes the data and / or information. The communication interface is further configured to output the processed data and / or information, so as to execute the method according to any possible implementation of the first or second aspect. In a seventh aspect, a computer-readable storage medium is provided, the computer-readable storage medium storing computer instructions. When the computer instructions are executed on a computer, the method according to any possible implementation of the first or second aspect is executed. In an eighth aspect, a computer program product is provided, comprising computer program code. When the computer program code is executed on a computer, the method according to any possible implementation of the first or second aspect is executed. In a ninth aspect, a communication system is provided, comprising the aforementioned transmitting device and receiving device. BRIEF DESCRIPTION OF THE DRAWINGS FIG1 is a structural diagram of an arrival angle positioning system applicable to the present application. FIG2 is a schematic diagram of an arrival angle measurement method applicable to the present application. FIG3 is a structural diagram of a departure angle positioning system applicable to the present application. Figure 4 is a flow chart of an angle determination method provided in an embodiment of the present application. Figure 5 is a schematic diagram of an AoA angle measurement based on a traditional single-tone signal provided in an embodiment of the present application. Figure 6 is a schematic diagram of an AoA angle measurement based on a multi-tone signal provided in an embodiment of the present application. Figure 7 is a schematic diagram of a baseband multi-tone signal provided in an embodiment of the present application. Figure 8 is a schematic diagram of up-conversion processing of a baseband multi-tone signal provided in an embodiment of the present application. Figure 9 is a schematic diagram of phase measurement of a baseband multi-tone signal provided in an embodiment of the present application. Figure 10 is a schematic diagram of two-dimensional (frequency dimension - antenna dimension) energy provided in an embodiment of the present application. Figure 11 is a schematic diagram of one-dimensional (antenna dimension) energy provided in an embodiment of the present application. Figure 12 is a schematic diagram of splicing angle measurement values ​​based on multi-tone signals provided in an embodiment of the present application. Figure 13 is a schematic diagram of the structure of an angle determination device provided in an embodiment of the present application. Figure 14 is a schematic diagram of the structure of another angle determination device provided in an embodiment of the present application. DETAILED DESCRIPTION OF THE EMBODIMENTS The technical solutions of this application will be described below in conjunction with the accompanying drawings. The technical solution of the present application can be applied to wireless personal area networks (WPANs). Currently, the standards adopted by WPANs are the Institute of Electrical and Electronics Engineers (IEEE) 802.15 series.WPANs can be used for communication between digital auxiliary devices within a small area, such as phones, computers, and accessories. Technologies supporting wireless personal area networks include Bluetooth, ZigBee, ultra-wideband (UWB), infrared data association (IrDA) connectivity, and home radio frequency (HomeRF). From a network perspective, WPANs sit at the bottom layer of the overall network architecture, providing wireless connections between devices within a small area, i.e., point-to-point short-range connections, and can be considered short-range wireless communication networks. Based on different application scenarios, WPANs are categorized into high-rate (HR) WPANs and low-rate (LR) WPANs. HR-WPANs can support various high-rate multimedia applications, including high-quality audio and video distribution, multi-megabyte music and image file transfer, and more. LR-WPANs can be used for general daily tasks. In a WPAN, devices are categorized as full-function devices (FFDs) and reduced-function devices (RFDs) based on their communication capabilities. FFDs can communicate with each other, as well as with RFDs. RFDs cannot communicate directly with each other; they can only communicate with one FFD or forward data through an FFD. The FFD associated with an RFD is called the coordinator for that RFD. RFDs are primarily used for simple control applications, such as light switches and passive infrared sensors. They transmit relatively small amounts of data, consume minimal transmission and communication resources, and thus have a low RFD cost. The coordinator can also be referred to as a personal area network (PAN) coordinator or central control node. The PAN coordinator is the master control node for the entire network, and each ad hoc network typically has only one PAN coordinator. It manages membership, link information, and packet forwarding. Optionally, the device (eg, a transmitting device or a receiving device) in the embodiment of the present application may be a device supporting the 802.15 series, for example, a device supporting 802.15.4a and 802.15.4z, as well as various WPAN standards currently under discussion or subsequent versions.In embodiments of the present application, the aforementioned devices may be communication servers, routers, switches, network bridges, computers or mobile phones, smart home devices, in-vehicle communication devices, etc. In embodiments of the present application, the aforementioned devices may be wireless communication chips, wireless sensors, or wireless communication terminals. For example, user terminals, user devices, access devices, subscriber stations, subscriber units, mobile stations, user agents, and user equipment that support Wi-Fi communication functions. User terminals may include various handheld devices with wireless communication functions, in-vehicle devices, wearable devices, Internet of Things (IoT) devices, computing devices, or other processing devices connected to wireless modems, as well as various forms of user equipment (UE), mobile stations (MS), terminals, terminal equipment, portable communication devices, handsets, portable computing devices, entertainment devices, gaming devices or systems, global positioning system devices, or any other suitable device configured to conduct network communication via a wireless medium. In addition, the device may support the 802.15.4ab standard or the next generation standard of 802.15.4ab. The device may also support multiple standards such as 802.15.4a, 802.15.4-2011, 802.15.4-2015, and 802.15.4z. The device may also support multiple wireless local area network (WLAN) standards in the 802.11 family, such as 802.11ax, 802.11ac, 802.11n, 802.11g, 802.11b, 802.11a, and the next generation of 802.11be. In the embodiment of the present application, the above-mentioned device includes a hardware layer, an operating system layer running on the hardware layer, and an application layer running on the operating system layer. The hardware layer includes hardware such as the central processing unit (CPU), memory management unit (MMU), and memory (also known as main memory). The operating system can be any one or more computer operating systems that implement business processing through processes, such as the Linux operating system, Unix operating system, Android operating system, iOS operating system, or Windows operating system. The application layer includes applications such as browsers, address books, word processing software, and instant messaging software.Furthermore, the embodiments of the present application do not specifically limit the specific structure of the execution body of the methods provided in the embodiments of the present application. As long as the method provided in the embodiments of the present application can be communicated according to the methods provided in the embodiments of the present application by running a program containing the code of the method provided in the embodiments of the present application, it is sufficient. For example, the execution body of the method provided in the embodiments of the present application may be an FFD or RFD, or a functional module within the FFD or RFD that can call and execute the program. Furthermore, various aspects or features of the present application may be implemented as methods, apparatuses, or articles of manufacture using standard programming and / or engineering techniques. The term "article of manufacture" as used in this application encompasses computer programs accessible from any computer-readable device, carrier, or medium. For example, computer-readable media may include, but are not limited to, magnetic storage devices (e.g., hard disks, floppy disks, or magnetic tapes), optical disks (e.g., compact discs (CDs), digital versatile discs (DVDs), etc.), smart cards, and flash memory devices (e.g., erasable programmable read-only memories (EPROMs), cards, sticks, or key drives). In addition, the various storage media described herein may represent one or more devices and / or other machine-readable media for storing information. The term "machine-readable medium" may include, but is not limited to, wireless channels and various other media capable of storing, containing, and / or carrying instructions and / or data. The technical solutions of this application may also be applied to wireless local area network systems such as the Internet of Things (IoT) network or Vehicle-to-X (V2X) network.Of course, the embodiments of the present application may also be applicable to other possible communication systems, such as the Long Term Evolution (LTE) system, the LTE frequency division duplex (FDD) system, the LTE time division duplex (TDD) system, the Universal Mobile Telecommunications System (UMTS), the Worldwide Interoperability for Microwave Access (WiMAX) communication system, the fifth generation (5G) communication system, and the future sixth generation (6G) communication system. It should be understood that AoA / AoD has been applied in low-power wireless narrowband technologies, and the technical solution provided in this application is applicable to a Bluetooth indoor positioning system. This Bluetooth indoor positioning system can be applied to indoor navigation devices, such as using a Bluetooth bracelet as a navigation terminal, to effectively solve the problem of blind people being unable to quickly, safely, and conveniently reach their target location from their current location when moving indoors, especially in public places such as hospitals, subway stations, and shopping malls. The basic principles of AoA / AoD are explained below using Bluetooth BLE AoA / AoD as an example. Figure 1 is a structural diagram of an AoA positioning system applicable to this application. As shown in Figure 1, it includes a transmitting device and a receiving device. The transmitting device has one antenna, and the receiving device has two or more antennas (for example, four antennas). For example, when performing Bluetooth BLE AoA angle measurement, the transmitting device sends a single-tone signal, i.e., a special Bluetooth signal with a sine wave baseband, which the Bluetooth protocol calls constant tone extension (CTE). Upon receiving the CTE, the transmitting device sends a single-tone signal. 2n·d·sin. The angle of incidence θ, or the orientation of the transmitting device relative to the receiving device, can then be calculated. Figure 3 is a structural diagram of an AoD positioning system applicable to this application. As shown in Figure 3, it includes a transmitting device and a receiving device. The receiving device has one antenna, and the transmitting device has two or more antennas (for example, four antennas). Exemplarily, when performing Bluetooth BLE AoD angle measurement, the transmitting device transmits a CTE signal segment while continuously switching between the antennas. While receiving the CTE single-tone signal, the receiving device determines the transmitting antenna corresponding to each portion of the CTE signal and samples the baseband signal corresponding to each antenna. The processor in the receiving device performs angle calculation based on the sampled baseband signal from each antenna. It should be understood that the AoA / AoD positioning systems shown in Figures 1 and 3 are merely illustrative and are not specifically limited in this application. The system is not limited to including additional devices, such as additional receiving devices. It should also be understood that Bluetooth BLE has 37 channels that can be used for AoA / AoD angle measurement, covering approximately 80M bandwidth in the 2.4GHz Industrial Scientific Medical band (ISM), with a spacing of 2MHz between adjacent channels. It should be noted that the frequency band that can be used for BLE AoA / AoD is 2.404 to 2.478GHz. For other Bluetooth BLE AoA / AoD contents, please refer to the existing Bluetooth 5.1 protocol. For the sake of brevity, we will not elaborate on them here. Currently, low-power narrowband wireless technologies (such as Bluetooth and Zigbee) are increasingly widely used in daily life. Compared with other wireless technologies such as 5G and WiFi, the advantages of low-power narrowband wireless technologies are: (1) very low power consumption, which means longer device usage time; (2) relatively simpler design and lower device cost. This has led to widespread adoption of low-power narrowband wireless technology not only in consumer devices (such as mobile phones, wearables, and smart homes), but also in a wide range of applications within the Industrial Internet of Things (IIoT). Low-power narrowband wireless technology not only connects devices but also measures the direction of travel between them (i.e., AoA / AoD), enabling device positioning. Bluetooth AoA / AoD, a representative AoA / AoD protocol within low-power narrowband wireless technology, has led to the increasing popularity of Bluetooth AoA / AoD indoor positioning systems.It should be understood that in an ideal environment (eg, without multipath reflection), the phase difference between AoA antennas does not vary much with the channel. For example, the signal wavelengths of the leftmost and rightmost Bluetooth LE channels differ by approximately 3%. Therefore, according to the aforementioned formula for phase difference and incident angle (p = 27i - d - sm 9), the phase difference measured for the leftmost and rightmost channels differs by approximately 3%. Furthermore, the more channels (or frequencies) used in BLE AoA / AoD angle measurement, the greater the amount of AoA / AoD information, and the more accurate the resulting angle estimate. However, multipath reflections exist in real indoor environments, resulting in different frequency responses for different channels (or frequencies). Because phase differences fluctuate across channels, the phase differences between multiple antennas in actual BLE AoA / AoD angle measurements vary with channel (i.e., frequency). This variation in phase difference with channel is significantly greater than the 3% variation in ideal conditions. Furthermore, for Bluetooth LE AoA / AoD, each AoA / AoD signal transmission can only measure the AoA / AoD at a single frequency. Information. If the angle measurement of the entire ISM band is required, all 37 channels of BLE need to be measured at an angle, which requires a longer angle measurement time as a whole, thereby increasing the power consumption of the device, reducing the capacity of the system, or the refresh rate of the device AoA / AoD angle measurement is low, and it cannot support the angle measurement of fast-moving devices. In summary, compared with the AoA / AoD measurement scheme of the current narrowband wireless technology, how to achieve fast and accurate AoA / AoD angle measurement is a technical problem that needs to be solved urgently. In view of this, the present application provides an angle determination method and device, which uses a multi-tone signal as a reference signal for AoA / AoD measurement, and when two adjacent AoA / AoD measurements are taken, a common frequency point is used to achieve the splicing of the measured phase values. Compared with the traditional method of using a single-tone signal for AoA measurement, the method disclosed in the present application can reduce the overall time to complete the AoA / AoD measurement of all frequency points using a multi-tone signal, thereby achieving fast and accurate AoA / AoD measurement. To facilitate understanding of the embodiments of the present application, A brief description of the terms or technologies involved in this application is given.

[0002] AoA: By using a single antenna to send packets with direction-finding capabilities, a low-energy (LE) device can make its direction available to a peer device. The peer device includes an RF switch and antenna array. It switches antennas and acquires IQ samples when receiving partial packets. These IQ samples are used to calculate the phase difference between the radio signals received by different elements of the antenna array, which in turn can be used to estimate the angle of arrival (AoA).

[0003] 2. AoD: By using multiple antennas to send data packets with direction finding capabilities and switching antennas while sending data packets, LE devices can make their direction available to peer devices. The peer device includes an RF switch and a single antenna. It receives data packets sent by each antenna and obtains IQ samples. Based on the IQ of each antenna, it calculates the phase difference between the antennas, which can be used to estimate the angle of departure (AoDo).

[0004] 3. Narrowband Signals: In this application, "narrowband signals" are used in contrast to "ultra-wideband signals." Ultra-wideband signals generally have a bandwidth of at least 500 MHz. Signals with a bandwidth smaller than that of ultra-wideband signals are considered narrowband signals. Optionally, narrowband signals include, but are not limited to, signals provided by the following wireless technologies: Bluetooth, ZigBee, technologies based on the 802.15.4 standard (such as Thread), and WiFi (including various 802.11 standards). Furthermore, these technologies may include cellular systems' narrowband internet of things (NB-IoT), long-term evolution-machine-to-machine (LTE-M), LoRa, Sigfox, and other future wireless technologies that may provide narrowband signals, without limitation.

[0005] 4. Line-of-sight (LOS)

[0006] LOS refers to the distance between the transmitting and receiving antennas where they can see each other. This means there are no obstacles between the two antennas that could affect signal propagation, allowing for complete signal transmission.

[0007] 5. Upconversion and Downconversion: Upconversion involves shifting the baseband signal's spectrum to a desired higher carrier frequency. Alternatively, upconversion modulates the baseband signal onto a carrier, or converts a signal modulated on a low-frequency carrier to a higher-frequency carrier. Specifically, the frequency-converted signal is mixed with a sinusoidal signal (LO) generated by a local oscillator (LO) to change the signal's frequency band. Taking the upper sideband signal after mixing is upconversion, meaning the frequency is raised; taking the lower sideband signal after mixing is downconversion, meaning the frequency is lowered.

[0008] 6. Single-Tone Signals and Multi-Tone Signals: A single-tone signal is a sinusoidal wave of a single frequency, meaning it has only one spectral line. A multi-tone signal is generated by superimposing multiple independent sinusoidal waveforms, meaning it has multiple spectral lines. To facilitate understanding of the embodiments of this application, the following points are provided: First, throughout this application, unless otherwise specified or logically conflicting, the terminology and / or descriptions across different embodiments are consistent and may be referenced across them. Technical features from different embodiments may be combined to form new embodiments based on their inherent logical relationships. Second, throughout this application, "at least one" refers to one or more, and "more than one" refers to two or more.

[0009] "And / or" describes the relationship between associated objects, indicating that three possible relationships exist. For example, "A and / or B" can mean: A exists alone, A and B exist simultaneously, or B exists alone, where A and B can be singular or plural. In the text description of this application, the character " / " generally indicates that the associated objects are in an "or" relationship. "At least one of the following" or similar expressions refers to any combination of these items, including any combination of single or plural items. For example, "at least one of a, b, and c" can mean: a, or b, or c, or a and b, or a and c, or b and c, or a, b, and c. A, b, and c can each be single or plural. Third, in this application, "first," "second," and various numerical numbers (e.g., #1, #2, etc.) indicate distinctions for ease of description and are not intended to limit the scope of the embodiments of this application. For example, different messages are distinguished, rather than being used to describe a specific order or sequence. It should be understood that the objects described in this way can be interchanged where appropriate, so as to be able to describe solutions other than the embodiments of the present application. For example, the first frequency point is -1.5 MHz, the second frequency point is -0.5 MHz, the third frequency point is 0.5 MHz, and the fourth frequency point is 1.5 MHz, and the four frequency points are different. In one possible implementation, a transmitting device includes N1 digital local oscillators (LOs) and radio frequency (RF) LOs. The N1 digital LOs correspond to the N1 frequency points. The transmitting device adds signals from the N1 digital LOs to obtain a first baseband multi-tone signal. The first baseband multi-tone signal is mixed with the signal from the RF LO. In other words, the transmitting device up-converts the first baseband multi-tone signal to obtain a first RF multi-tone signal. In one possible implementation, the frequency interval between any two adjacent frequency points among the N1 frequency points is the same. For example, the frequency interval between any two adjacent frequency points is 1 MHz or 2 MHz, for example. For example, the first multi-tone signal includes a first frequency point, a second frequency point, and a third frequency point, the first frequency point is 0 MHz, the second frequency point is 1 MHz, and the third frequency point is 2 MHz. Then, the frequency interval between the first frequency point and the second frequency point, and the frequency interval between the second frequency point and the third frequency point are the same, that is, 1 MHz. Optionally, the frequency interval between any two adjacent frequency points among the N1 frequency points of the first multi-tone signal may also be different, and this is not specifically limited.

[0010] In step S4, referring to Figures 5 to 20, a transmitting device transmits a first multi-tone signal. Correspondingly, a receiving device receives the first multi-tone signal. Exemplarily, the transmitting device is an AoA / AoD transmitting device, and the receiving device is an AoA / AoD receiving device. Optionally, the transmitting device and the receiving device may have various possible application scenarios. Exemplarily, the transmitting device mentioned in the following embodiments may be an initiating site, and the receiving device a responding site; or, the transmitting device may be a responding site, and the receiving device may be an initiating site. Optionally, the transmitting device may be a positioning device, and the second device may be a mobile tag; or, the transmitting device may be a mobile tag, and the receiving device may be a positioning device. Exemplarily, for AoA angle measurement, the transmitting device continuously transmits the first multi-tone signal via a single antenna, and the receiving device receives the first multi-tone signal via k antennas. Exemplarily, for AoD angle measurement, the transmitting device continuously transmits the first multi-tone signal via k antennas, and the receiving device receives the first multi-tone signal via a single antenna. In one possible implementation, a receiving device receives a first RF multi-tone signal through an antenna. The first RF multi-tone signal is obtained by up-converting the first baseband multi-tone signal. The receiving device down-converts the first RF multi-tone signal to obtain the first baseband multi-tone signal. Exemplarily, the N1 frequency points of the first RF multi-tone signal are obtained by adding an fc frequency to the N1 frequency points of the first baseband multi-tone signal, where fc is an RF LO frequency. This ensures that the frequency band of the up-converted first baseband multi-tone signal, that is, the first RF multi-tone signal, covers the entire BLE AoA frequency band, for example, 2.404 to 2.478 GHz. It should be noted that in this implementation, the first RF multi-tone signal is the first multi-tone signal. For example, when determining the angle of arrival of a signal, the phase difference of the RF signal between two antennas needs to be measured. Given that the frequency of the RF signal changes rapidly, directly measuring the phase of the RF signal is difficult to implement. Therefore, in engineering implementation, the RF signal is down-converted to a lower-frequency baseband signal and then the phase of the baseband signal is measured to indirectly obtain the phase of the RF signal. The phase of the RF LO during the down-conversion process affects the phase value of the baseband signal. However, since the RF LO has the same effect on the phases of k antennas, the effect of the RF LO on the phases can be offset when calculating the phase differences between the k antennas.In one possible implementation, the N1 digital LOs have the same initial phase when they are turned on, and the i-th digital LO has the same initial phase at a first moment and a second moment. The first moment is the time when the first multi-tone signal is transmitted, and the second moment is the time when the second multi-tone signal is transmitted. Alternatively, the first moment is the time when the first multi-tone signal is received, and the second moment is the time when the second multi-tone signal is received. This implementation ensures that the multiple digital LOs of the transmitting device have the same initial phase when they are turned on, and the initial phase value of the same digital LO is also the same during each angle measurement. Similarly, the multiple digital LOs of the receiving device have the same initial phase when they are turned on, and the initial phase value of the same digital LO is also the same during each angle measurement. This avoids the introduction of additional phase errors and improves angle measurement accuracy. It should be noted that the multiple RF LOs and digital LOs of the receiving device remain in a locked state. In other words, in this implementation, the phase values ​​corresponding to different frequencies of each antenna need to be obtained by switching antennas. To prevent LOs (including RF LOs and digital LOs) from introducing additional phases, during antenna switching, for example, when measuring the angle of arrival of a signal, the RF LO and multiple digital LOs of the receiving device are rotated continuously. The multiple digital LOs and RF LOs of the transmitting device are also rotated continuously, meaning that the multi-tone signal is continuously transmitted. In one possible implementation, the transmitting device transmits a second signal; in response, the receiving device receives a second multi-tone signal. The second multi-tone signal includes N2 frequencies, with M common frequencies between N2 and N1. N2 is an integer greater than or equal to 2, and M is an integer greater than or equal to 1 and less than the minimum of N1 and N2. For example, N2 = 3, meaning the second multi-tone signal includes a first frequency, a second frequency, and a third frequency. For example, the first frequency is 1.5 MHz, the second frequency is 2.5 MHz, and the third frequency is 3.5 MHz, with the three frequencies being different from each other. The fourth frequency point of the first multi-tone signal is 1.5 MHz, that is, the first multi-tone signal and the second multi-tone signal have a common frequency point, that is, 1.5 MHz.

[0011] S430: The receiving device performs phase measurement on the first multi-tone signal.

[0012] S440: The receiving device obtains first phase values ​​corresponding to k antennas of the first device at N1 frequency points. Here, k is an integer greater than or equal to 2. It should be understood that the first phase values ​​can be viewed as a phase matrix with k columns and N1 rows. The number of phase values ​​in the phase matrix can be greater than or equal to 2 and less than or equal to k multiplied by N1. For example, if N1 is equal to 4 and k is equal to 2, the first phase values ​​represent a phase matrix with 2 columns and 4 rows, including phase values ​​corresponding to the two antennas at four frequency points, i.e., 8 phase values. Of course, interference from other signals may cause an antenna to fail to collect a phase value at a certain frequency point during the angle measurement process of the first multi-tone signal, or a phase value error may be large. This application does not specifically limit this. In one possible implementation, a receiving device includes N1 digital LOs, each corresponding to N1 frequency points. The receiving device performs phase measurement on a first multi-tone signal and obtains first phase values ​​corresponding to k antennas of the first device at the N1 frequency points. This includes: the i-th digital LO of the receiving device performs digital down-conversion processing on the first multi-tone signal, performs IQ averaging processing on the digitally down-converted first multi-tone signal, and obtains the first phase values ​​corresponding to the k antennas of the first device at the i-th frequency point, where i is an integer greater than or equal to 1 and less than or equal to N1. In this implementation, the receiving device uses IQ averaging to obtain the average IQ of a signal at a certain frequency point at a certain antenna (the IQ values ​​of other frequencies are canceled out). Based on this average IQ, the phase value of the signal at that frequency point at the antenna can be calculated. Similarly, the phase value of the signal at another antenna can be obtained, and then the phase difference between the two antennas can be obtained for calculating the angle of arrival. It should be understood that the above process is applicable to the processing of signals at all other frequencies. In one possible implementation, when the first device is a receiving device, the angle of the signal from the first device is the angle of arrival of the receiving device. Exemplarily, if the first device is a receiving device, the transmitting device transmits the first multi-tone signal via a single antenna, and the receiving device receives the first multi-tone signal via k antennas. During antenna switching, the receiving device obtains phase values ​​corresponding to each antenna at N1 frequency points. The angle of arrival (i.e., 0) is determined by comparing the difference in phase values ​​corresponding to the same frequency point between the two antennas and using the formula for the phase difference and the angle of incidence of the signal: cp = 27t - d - sine. In another possible implementation, when the first device is a transmitting device, the angle of the signal from the first device is the angle of departure of the transmitting device.For example, the first device is a transmitting device. The transmitting device transmits a first multi-tone signal via multiple antennas, and the receiving device receives the first multi-tone signal via a single antenna. While the transmitting device switches antennas and continuously transmits the first multi-tone signal, the receiving device obtains phase values ​​corresponding to each antenna at N1 frequency points. The departure angle can be determined by comparing the difference in phase values ​​corresponding to the same frequency points for the two antennas of the transmitting device. In one possible implementation, the receiving device performs phase measurement on the second multi-tone signal and obtains second phase values ​​corresponding to N2 frequency points for k antennas of the first device. The receiving device determines the angle of the first device's signal based on the obtained second phase values. Alternatively, the receiving device determines the angle of the first device's signal based on the obtained first and second phase values. In other words, the angle of the first device's signal can be determined by measuring the phase values ​​corresponding to the second multi-tone signal. Alternatively, the angle of the first device's signal can be determined by combining the phase values ​​of the first and second multi-tone signals. It should be understood that the second phase values ​​can be viewed as a phase matrix with k columns and N2 rows. The number of phase values ​​in the phase matrix can be greater than or equal to 2 and less than or equal to k times N2. For example, if N2 is equal to 3 and k is equal to 2, then the second phase value represents a phase matrix with two columns and three rows, including phase values ​​corresponding to three frequency points for the two antennas, i.e., six phase values. Of course, interference from other signals may cause one antenna to fail to collect a phase value at a certain frequency point during the angle measurement of the second multi-tone signal, or a phase value error may be large. This application does not specifically limit this. In one possible implementation, a receiving device determines the angle of a signal from the first device based on the acquired first and second phase values, including: the receiving device determines a phase compensation value based on the acquired first and second phase values; the receiving device compensates the first phase value based on the phase compensation value; and the receiving device determines the angle of the signal from the first device based on the compensated first and second phase values. Optionally, the receiving device determines the angle of the signal from the first device based on the acquired first and second phase values, including: the receiving device determines a phase compensation value based on the acquired first and second phase values; the receiving device compensates the second phase value based on the phase compensation value; and the receiving device determines the angle of the signal from the first device based on the compensated second and second phase values.For example, N1=4, the four frequencies of the first multi-tone signal are respectively -1.5 MHz, -0.5 MHz, 0.5 MHz, and 1.5 MHz; N2=3, the three frequencies of the second multi-tone signal are respectively 1.5 MHz, 2.5 MHz, and 3. The common frequency is 1.5 MHz. For example, when switching to a certain antenna, the phase value of the first multi-tone signal measured at -1.5 MHz is 1 / 2, and the phase value of the second multi-tone signal measured at -1.5 MHz is 1 / 2. Compensation is performed based on the phase values ​​so that the phase value of the first multi-tone signal measured at -1.5 MHz and the phase value measured at -1.5 MHz are the same. This allows the phase values ​​to be spliced ​​to obtain a more accurate phase value. For example, the target phase matrix after splicing includes the phase values ​​of k antennas at 6 (N1+N2-). Phase value. It should be noted that when splicing the phase values ​​corresponding to the first multi-tone signal and the second multi-tone signal, the initial phase of the RF LO in the two measurement processes can be any value. By adopting the method of sharing the frequency point (or channel), the difference between the initial phases of the RF LO of the two angle measurements is calculated, and the initial phase value of the RF LO can be compensated. Therefore, the influence of errors on the angle measurement results of the signal can be avoided or reduced, and this implementation method can improve the angle measurement accuracy. In one possible implementation method, the time interval between the sending moments of the first multi-tone signal and the second multi-tone signal, and the time interval between the receiving moments of the first multi-tone signal and the second multi-tone signal are the same. Based on this implementation method, it is possible to achieve that the flight time Offset of the signal remains unchanged during the entire measurement process, avoiding The difference between the two, for example, can be processed by averaging to accurately measure the angle of the signal. According to the solution provided in this application, by receiving a multi-tone signal and performing phase measurement on the multi-tone signal, the angle of the signal of the first device is determined based on the obtained measurement value. Compared with traditional single-tone signal phase measurement, using multi-tone signals to determine the angle can quickly obtain phase values, improve measurement efficiency, and achieve rapid angle measurement. It should be understood that although the bandwidth of narrowband wireless devices is narrower than other wireless devices, it generally has a bandwidth of several MHz. The technical solution of this application utilizes this bandwidth of several MHz to perform AoA / AoD angle measurement using multi-tone signals, which can more quickly complete AoA / AoD angle measurements at multiple frequency points. Taking AoA angle measurement as an example, the following, in conjunction with Figures 5 to 12, specifically describes how to measure the phase values ​​of the transmitted and received multi-tone signals to determine the angle of arrival; and how to quickly and accurately identify and determine the angle of arrival corresponding to the LOS signal based on the splicing of the phase values ​​of the multi-tone signals. It should be noted that the technical solution is also applicable to the determination of the departure angle, and the specific implementation method is similar to the method for determining the arrival angle. For the sake of brevity, this application will not go into too much detail. Figure 5 is a schematic diagram of an AoA angle measurement based on a traditional single-tone signal provided by an embodiment of the present application. As shown in Figure 5, the horizontal axis is time and the vertical axis is frequency. Taking k antennas as an example, in the AoA angle measurement based on a single-tone signal, only the phase of a certain antenna at one frequency point can be measured at a time. For example, at time t1, the receiving device can measure the phase (pi) corresponding to antenna 1 at frequency fl l; then switch to antenna 2 for AoA angle measurement, at time t2, the receiving device can measure the phase (q) corresponding to antenna 2 at frequency fl l2; and so on, switch to antenna k for measurement, at time tk, the receiving device can measure the phase (p) corresponding to antenna k at frequency fl l. koThat is, during the AoA angle measurement process, after k-1 antenna switches, the receiving device can obtain all phases of k antennas at the same frequency point fl 1, i.e., a phase array of size k. Figure 6 is a schematic diagram of AoA angle measurement based on multi-tone signals, provided in an embodiment of the present application. As shown in Figure 6, the abscissa represents time, and the ordinate represents frequency. Taking k antennas and N = 4 tones as an example, in AoA angle measurement based on multi-tone signals, the phases of a particular antenna at multiple frequencies can be measured simultaneously at a single moment. For example, at time t1, the receiving device can simultaneously measure the phases (pi~(p4) corresponding to antenna 1 at frequencies fl1~f44; then, the receiving device switches to antenna 2 for AoA angle measurement. At time t2, the receiving device can simultaneously measure the phases (q)5~(q)8 corresponding to antenna 2 at frequencies fl1~f44. Similarly, the receiving device switches to antenna k for AoA angle measurement. At time tk, the receiving device can simultaneously measure the phases (p4k-3~(p4k) corresponding to antenna k at frequencies fl1~f44. That is, during the AoA angle measurement process, after k-1 antenna switching operations, the receiving device can obtain the phases of k antennas at multiple frequency points (e.g., fl1~f44), i.e., a 4×k phase matrix. It should be understood that the frequency fl1 shown in FIG5 is the frequency of the RF signal, i.e., the frequency of the RF signal corresponding to the up-conversion processing of the baseband signal at frequency fl, e.g., 2.450 GHz. Similarly, The frequency points fl 1 to f44 shown in FIG6 are also RF signal frequencies, i.e., the frequencies of the RF signals corresponding to the up-conversion processing of the baseband signal frequency points fl to f4, for example, 2.450 GHz to 2.480 GHz. It should be noted that fl 1 shown in FIG5 and fl 1 to f44 shown in FIG6 are merely examples to facilitate understanding of the solution, and this application does not specifically limit the number of frequency points or their specific values. Based on the AoA angle measurement method shown in FIG5 and FIG6, for N adjacent frequency points, the traditional AoA method requires N AoA angle measurements to achieve full coverage. However, the multi-tone AoA method (using N tones) only requires a single AoA angle measurement to achieve full coverage.That is, the multi-tone AoA method can reduce the single-tone AoA angle measurement time to one-Nth. For example, for the four tones shown in FIG6 , the overall single-tone AoA angle measurement time shown in FIG5 can be reduced to 25%. It should be noted that the number N=4 of the multi-tone signal shown in FIG6 is merely an example to facilitate understanding of the technical solution. This application does not specifically limit the number N of tones in the multi-tone signal or the frequency intervals between the tones. Optionally, to uniformly measure AoA angles across the entire frequency band, embodiments of this application may be described using the same frequency interval between the tones. For example, the frequency intervals between f1 to f4 are the same. The following describes the specific implementation of multi-tone signal transmission and reception, as well as phase measurement, using FIG7 to FIG9 . FIG7 is a schematic diagram of a baseband multi-tone signal provided in an embodiment of this application. As shown in Figure 7, assume that N = 4 tones, and the frequency of each tone corresponds to fl, f2, f3, and f4. For example, fl is -1.5 MHz, f2 is -0.5 MHz, f3 is +0.5 MHz, and f4 is +1.5 MHz. The intervals between the frequencies fl through f4 can be the same or different, and this application does not specifically limit this. Optionally, to achieve uniform AoA measurement across the entire frequency band, the frequency intervals between fl through f4 in this embodiment of the present application can be set to be the same. It should be noted that the frequency band from fl to f4 should not exceed the bandwidth supported by the device. Figure 8 is a schematic diagram of up-conversion processing of a multi-tone signal provided by an embodiment of the present application. As shown in Figure 8, it includes a radio frequency local oscillator (RF LO) and multiple digital LOs (four digital LOs as shown). The digital LOs can be implemented using a lookup table that stores cosine waveforms, and the four digital LOs correspond to N = 4 tones. For example, the frequencies of the four tones corresponding to the four digital LOs are, in order, fl, f2, f4, and f5. In other words, the frequencies of the digital LOs correspond one-to-one with the frequencies of the baseband multi-tone signals. The present application does not specifically limit the values ​​of fl, f2, f4, and f6. For example, fl can be -1.5 MHz, f2 can be -0.5 MHz, f6 can be +0.5 MHz, and f4 can be +1.5 MHz. The frequency of the RF LO is fc. Taking BLE AoA angle measurement as an example, fc can be in the 2.404 to 2.478 GHz frequency band.When transmitting a multi-tone signal, the transmitting device first sums the signals of multiple digital LOs to generate a baseband multi-tone signal (as shown in Figure 8). This signal is then sent to the RF LO via a digital-to-analog converter (DAC), or up-converted via an all-digital phase-locked loop (ADPLL), before being transmitted via the antenna. For example, during the up-conversion process, the frequencies of the four tones fl through f4 in the baseband multi-tone signal can be uniformly increased by 2.402 GHz, corresponding to the Bluetooth channel frequency band of 2.404 to 2.478 GHz. In other words, based on this implementation, the frequencies of the four tones of the baseband multi-tone signal shown in FIG7 are uniformly right-shifted by 2.402 GHz. When receiving the multi-tone signal, the receiving device first down-converts the signal through the RF LO to obtain a baseband multi-tone signal. The baseband multi-tone signal is then sent to four digital LOs for "digital down-conversion," i.e., the signals corresponding to the frequencies of the four digital LOs are converted into direct current (DC) signals (understandably). Phase / Quadrature, IQ) is averaged, and the IQ accumulation cycles used are:

[0013] 1 1 1 1 1

[0014] C is the least common multiple of the phases of the M and N signals. This can cancel the influence of the other three signals on the third f3 signal, so that the phase included in the final average IQ packet U-l3 is the phase of the third f3 signal. Similarly, the phases of the other three signals can be obtained. It should be noted that in multi-tone AoA angle measurement, the receiving device needs to switch antennas and measure the phase values corresponding to each antenna for angle measurement. When switching to a certain antenna, the receiving device can use the above method to measure the phases of each tone for angle measurement. To avoid the introduction of additional phase by the LO (including RF LO and digital LO), during the antenna switching process, the RF LO and digital LO of the receiving device need to keep rotating. Similarly, the RF LO and digital LO of the transmitting device also need to keep rotating, that is, continuously transmit multi-tone signals. According to the technical solution of this application, using multi-tone signals as the reference signals for AoA / AoD angle measurement can complete the AoA / AoD angle measurement of all frequency points more quickly, which means that the power consumption required for AoA / AoD is lower. For battery-powered devices, it can increase the standby time of the device; a higher system capacity can perform AoA / AoD angle measurement for more devices; a faster angle refresh rate can locate devices with faster speeds. Based on the above method 400, a single angle measurement of multi-tone signal AoA / AoD can obtain an N x k - For example, XT <PTX-i is the initial phase of the digital LO corresponding to the i-th tone in the transmitting device. The signal of the RF LO of the receiving device is: 2πf7 + φrx - Error! Digit expected., and the signal of the digital LO corresponding to the i-th tone of the receiving device is: 2πfi + φrx - Error! Digit expected. The relationship between the obtained phase difference and TT satisfies: zfcpy = -2K (f r - fj) • (T + T offset ) Acpjj = -2π(fi - fj) • (T + Toffset). As shown, the abscissa is the time of flight TOF (ns) of the multi-tone signal from the transmitting device to the receiving device, and the ordinate is the AoA angle. According to the relative values of ToF on the abscissa, it can be seen that the TOF of the peak on the right is about 20 ns, and the corresponding AoA angle is about 60°. The TOF of the peak on the left is about 10 ns, and the corresponding AoA angle is about -10°. Obviously, the TOF on the left is less than the TOF on the right. Therefore, it can be determined that the peak on the left (pointed by the arrow) is the direct line of sight. When only considering the information of the antenna dimension without considering the information of the frequency dimension, that is, in the single-tone AoA scenario, the one-dimensional energy diagram shown in Figure 11 below can be obtained. Figure 11 is a schematic diagram of one-dimensional (antenna dimension) energy provided by an embodiment of the present application. As shown in Figure 11, the abscissa is the AoA angle, and the ordinate is the corresponding Bartlett spectrum. It can be seen that the energies of the two peaks on the left and right are equal, about 5.8 x 10^4. This implementation method cannot be used to determine which peak is the direct line of sight, and thus cannot determine which (-10° and 60°) can be used as the final AoA estimate value. In summary, using the information of the frequency dimension to analyze the time of flight TOF can further assist in resolving the direct line of sight, and the resolution ability of this method depends on the size of the frequency dimension. It should be understood that the wider the frequency band, the stronger the TOF resolution ability, that is, the two signals with closer TOF can be resolved. For low-power narrowband wireless technologies, since the bandwidth is only several MHz, therefore, the present application proposes to splice multiple multi-tone AoA angle measurement values to increase the width of the frequency band, that is, to increase the N value in the N x k matrix, and then to improve the resolution ability of the multi-path signal TOF. It should be understood that the phase difference between the two frequency points fi and fj after splicing still satisfies the above formula Δφ = -2π(fi - fj)·τ + φTX-RF + (φTX-τ - φRX-RF) - φRX-τ, which can be used for the resolution of the multi-path signal TOF. Figure 12 is a schematic diagram of the splicing of the AoA angle measurement values based on multi-tone signals provided by an embodiment of the present application. As shown in Figure 12, the abscissa is time, and the ordinate is frequency. In order to keep τ or φ constant during the entire angle measurement process, that is, τ is the fixed time deviation LOffset between the digital LO starting points of the transmitting device and the receiving device in each AoA angle measurement.The time interval between the digital LO start times in two adjacent AoA angle measurements of the transmitting device is T, and the time interval between the digital LO start times in two adjacent AoA angle measurements of the receiving device is also T, that is, the two time intervals need to be the same. Additionally, when the transmitting device turns on the digital LO, the initial phases of all the digital LOs of the transmitting device are the same (i.e., for different i, <PTX - i> is the same), and the same initial phase is used for each AoA angle measurement. It should be noted that each time a new AoA angle measurement starts, the phase lock loop (PLL) of the RF circuit will relock, which will result in the initial phase of the RF LO (e.g., <PTX - RF>, <VTX - RF> and <RX - RF> at that time) being an arbitrary value that is unknown. Therefore, in order to achieve better phase value splicing, this application needs to ensure that there is one or more common frequency points in any two adjacent AoA angle measurements. For example, there is a common frequency point f1 (or a common channel) in the first and second AoA angle measurements shown in FIG. 13. By comparing the phase measurement values of the same frequency point in two AoA angle measurements (i.e., the difference <VTX - RF> - <VRX - RF> between them), the initial phase of the RF LO of the transmitting device and the influence of the initial phase of the RF LO of the receiving device on the phase measurement value can be obtained, and then this phase difference is used to compensate one set of AoA angle measurement values, so that these two AoA angle measurement values can be spliced to form a larger phase matrix. For example, assume that the number of common frequency points between two adjacent AoA angle measurements is M (M

Claims

Claims 1. A method for determining an angle, characterized in that: include: The receiving device receives a first multi-tone signal, where the first multi-tone signal includes N1 frequency points, where N1 is an integer greater than or equal to 2; The receiving device performs phase measurement on the first multi-tone signal; the receiving device obtains first phase values ​​corresponding to the k antennas of the first device at the N1 frequency points, where k is an integer greater than or equal to 2; the receiving device determines the angle of the signal of the first device based on the obtained first phase value.

2. The method according to claim 1, characterized in that When the first device is the receiving device, the angle of the signal of the first device is the arrival angle of the receiving device; or when the first device is the sending device, the angle of the signal of the first device is the departure angle of the sending device.

3. The method according to claim 1 or 2, characterized in that The receiving device includes N1 digital local oscillators (LOs), the N1 digital LOs correspond one-to-one to the N1 frequency points, the receiving device performs phase measurement on the first multi-tone signal, and the receiving device obtains first phase values ​​corresponding to k antennas of the first device at the N1 frequency points, including: the i-th digital LO of the receiving device performs digital down-conversion processing on the first multi-tone signal, performs IQ averaging processing on the first multi-tone signal after digital down-conversion, and obtains the first phase values ​​corresponding to the k antennas of the first device at the i-th frequency point, where i is an integer greater than or equal to 1 and less than or equal to N1.

4. The method according to any one of claims 1 to 3, characterized in that The receiving device determines the angle of the signal of the first device based on the obtained first phase value, including: the receiving device determines the angle of the signal of the first device based on the phase value corresponding to the first antenna at the i-th frequency point and the difference between the phase values ​​corresponding to the second antenna at the i-th frequency point; wherein the first antenna and the second antenna are any two antennas among the k antennas, and i is an integer greater than or equal to 1 and less than or equal to N1.

5. The method according to any one of claims 1 to 4, characterized in that The frequency interval between any two adjacent frequency points in the N1 frequency points is the same.

6. The method according to any one of claims 1 to 5, characterized in that The method also includes: the receiving device receiving a second multi-tone signal, the second multi-tone signal including N2 frequency points, the N2 frequency points and the N1 frequency point having M common frequency points, N2 is an integer greater than or equal to 2, and M is an integer greater than or equal to 1 and less than the minimum value of N1 and N2.

7. The method according to claim 6, characterized in that The method further includes: performing, by the receiving device, phase measurement on the second multi-tone signal; obtaining, by the receiving device, second phase values ​​corresponding to the N2 frequency points of the k antennas of the first device; determining, by the receiving device, the angle of the signal of the first device based on the obtained second phase values; or determining, by the receiving device, the angle of the signal of the first device based on the obtained first phase value and the second phase value. 22 The angle of the number.

8. The method according to claim 7, characterized in that The receiving device determines the angle of the signal of the first device based on the acquired first phase value and the second phase value, including: the receiving device determines a phase compensation value based on the acquired first phase value and the second phase value; the receiving device compensates the first phase value based on the phase compensation value; the receiving device determines the angle of the signal of the first device based on the compensated first phase value and the second phase value; or, the receiving device compensates the second phase value based on the phase compensation value; the receiving device determines the angle of the signal of the first device based on the compensated second phase value and the first phase value.

9. The method according to any one of claims 6 to 8, characterized in that The time interval between the sending times of the first polyphonic signal and the second polyphonic signal and the time interval between the receiving times of the first polyphonic signal and the second polyphonic signal are the same.

10. The method according to any one of claims 6 to 9, characterized in that The N1 digital LOs have the same initial phase when turned on, and the i-th digital LO has the same initial phase corresponding to a first moment and a second moment, the first moment is the sending moment of the first multi-tone signal, and the second moment is the sending moment of the second multi-tone signal; or, the first moment is the receiving moment of the first multi-tone signal, and the second moment is the receiving moment of the second multi-tone signal.

11. A method for determining an angle, characterized in that: The method includes: a sending device generating a first multi-tone signal, the first multi-tone signal including N1 frequency points, where N1 is an integer greater than or equal to 2; the sending device sending the first multi-tone signal, the first multi-tone signal being used to determine an angle of a signal of the first device.

12. The method according to claim 11, characterized in that When the first device is a receiving device, the angle of the signal of the first device is the arrival angle of the receiving device; or when the first device is the sending device, the angle of the signal of the first device is the departure angle of the sending device.

13. The method according to claim 11 or 12, characterized in that The frequency interval between any two adjacent frequency points in the N1 frequency points is the same.

14. The method according to any one of claims 11 to 13, characterized in that The method also includes: the sending device generating a second multi-tone signal, the second multi-tone signal including N2 frequency points, the N2 frequency points and the N1 frequency point having M common frequency points, N2 is an integer greater than or equal to 2, and M is an integer greater than or equal to 1 and less than the minimum value of N1 and N2; and the sending device sending the second multi-tone signal.

15. The method according to claim 14, characterized in that The time interval between the sending times of the first polyphonic signal and the second polyphonic signal and the time interval between the receiving times of the first polyphonic signal and the second polyphonic signal are the same.

16. The method according to claim 14 or 15, characterized in that The sending device includes N1 digital books a machine oscillator LO, the N1 digital LOs correspond to the N1 frequency points, the N1 digital LOs have the same initial phase when turned on, and the i-th digital LO has the same initial phase corresponding to a first moment and a second moment, i is an integer greater than or equal to 1 and less than or equal to N1, the first moment is a time when the first multi-tone signal is sent, and the second moment is a time when the second multi-tone signal is sent; or, the first moment is a time when the first multi-tone signal is received, and the second moment is a time when the second multi-tone signal is received.

17. An angle determination device, characterized in that: include: A unit for implementing the method of any one of claims 1 to 8; or, a unit for implementing the method of any one of claims 9 to 16.

18. An angle determination device, characterized in that: include: a processor coupled to the memory; The processor is configured to execute the computer program stored in the memory, so that the apparatus performs the method according to any one of claims 1 to 16.

19. A chip, characterized in that: include: A processor, configured to call and run a computer program from a memory, so that a communication device equipped with the chip executes the method according to any one of claims 1 to 16.

20. A computer program, characterized in that When the computer program is executed by the device, the method according to any one of claims 1 to 16 is implemented.

21. A computer-readable storage medium, characterized in that: include: The computer-readable storage medium stores a computer program, and when the computer program is executed, the computer is enabled to perform the method according to any one of claims 1 to 16.

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