Signal transmission method and related apparatus

Abstract

The present invention provides a signal transmission method, a communication device, a chip and related devices, and a program storage medium. [Solution] A communication transmission method in an ultra-wideband (UWB) system includes a first initiating device transmitting a polling frame. The polling frame includes time-frequency position information of N first ultra-wideband (UWB) segment signals and first delay information for each of M second responding devices to reply to the first initiating device in a response frame. The method also includes the first initiating device receiving a plurality of response frames based on the timestamp of the polling frame and the first delay information for each second responding device to reply to the first initiating device in a response frame.

Description

Technical Field

[0001] This application is a divisional application of Japanese Patent Application No. 2024-553442, which claims priority from Chinese Patent Application No. 202210225959.X, titled "Signal Transmission Method and Related Device", filed with the China National Intellectual Property Administration on March 7, 2022, and the entire content of the Chinese Patent Application is incorporated herein by reference.

[0002] This application relates to the field of communication technologies, and particularly to signal transmission methods and related devices.

Background Art

[0003] Ultra-wideband (UWB) technology is a wireless carrier communication technology. In this technology, data transmission is performed by transmitting and receiving extremely narrow pulses of nanoseconds or shorter. Therefore, UWB technology occupies a wide spectrum range.

[0004] In ranging, the accuracy of measurement or sensing is related to the signal bandwidth. A larger signal bandwidth indicates higher accuracy sensing or ranging. Therefore, it has been proposed to use a UWB system to perform ranging in order to improve the accuracy of ranging.

[0005] Currently, when an initiator uses a UWB system to perform ranging on one responder, the initiator needs to complete ranging on the responder within a plurality of milliseconds. In this case, if the initiator uses the process of performing ranging on one responder to perform ranging on a plurality of responders, the initiator can only complete ranging on the plurality of responders after a long time, resulting in low ranging efficiency of the initiator.

Summary of the Invention

[0006] Embodiments of this application provide a signal transmission method and related device that help improve ranging efficiency.

[0007] According to a first aspect, one embodiment of the present application provides a signal transmission method in which a first initiating device transmits a polling frame. The polling frame includes time-frequency position information of N first ultra-wideband (UWB) segment signals and first delay information for each of M second responding devices to reply to the first initiating device in a response frame. The first initiating device receives a plurality of response frames based on the timestamp of the polling frame and the first delay information for each second responding device to reply to the first initiating device in a response frame, where N and M are integers of 2 or more.

[0008] In this embodiment of the application, a polling frame transmitted by a first initiating device includes first delay information for each of M second responding devices to reply in a response frame, so that some or all of the M second responding devices can participate in the ranging round of the first initiating device by replying in response frames at different times determined based on different first delays. Furthermore, this helps the first initiating device to perform ranging for multiple second responding devices in a short amount of time, thereby improving ranging efficiency.

[0009] In one optional implementation, the polling frame further includes second delay information for each second responding device to respond to the first UWB segment signal from the first initiating device. Thus, the first initiating device can further transmit N first UWB segment signals separately based on the time-frequency position information of the N first UWB segment signals. The first initiating device receives a plurality of second UWB segment signals separately based on the second delay information for each second responding device to respond to the first UWB segment signal from the first initiating device.

[0010] It can be seen that a first initiating device initiates a ranging round by transmitting a first UWB segment signal, and the first initiating device can receive second UWB segment signals, which are returned by multiple second responding devices for all first UWB segment signals, at different times determined based on different second delay information. Thus, the first initiating device performs ranging on multiple second initiating devices based on multiple transmitted first UWB signals and multiple received second UWB segment signals.

[0011] In one implementation of another option, the polling frame further includes identical third delay information for M second responding devices to respond to the first UWB segment signal from the first initiating device, and the orthogonal sequence index of each second responding device. Thus, the first initiating device can further transmit N first UWB segment signals separately based on the time-frequency position information of the N first UWB segment signals. The first initiating device receives multiple first orthogonal UWB segment signals separately based on the third delay information and the orthogonal sequence index of each second responding device.

[0012] It can be seen that a first initiating device initiates a ranging round by transmitting a first UWB segment signal, and the first initiating device can receive first orthogonal UWB segment signals, which are returned by multiple second responding devices in response to the first UWB segment signal, at the same time determined based on third delay information. The multiple first orthogonal UWB segment signals are orthogonal to each other. This scheme also helps the first initiating device perform ranging on multiple second initiating devices based on the multiple transmitted first UWB signals and the multiple received first orthogonal UWB segment signals.

[0013] In one optional implementation, if the polling frame further includes identical third delay information for M second responding devices to respond to a first UWB segment signal from the first initiating device, and the orthogonal sequence index of each second responding device, the first initiating device is active when it transmits N first UWB segment signals and receives a plurality of first orthogonal UWB segment signals. The first initiating device is idle during the interval time of the N first UWB segment signals, other than the time of transmitting the N first UWB segment signals and the time of receiving the plurality of first orthogonal UWB segment signals.

[0014] Thus, the first start device can be active when it transmits N first UWB segment signals and receives multiple first orthogonal UWB segment signals, and can be idle for the remaining time in the interval between the N first UWB segment signals. Therefore, the active time of the first start device can be reduced, thereby reducing the power consumption of the first start device.

[0015] In one implementation of further alternative options, the polling frame further includes a fourth delay information for each second responding device to transmit a data frame to the first initiating device. Thus, the first initiating device can further receive a plurality of data frames based on the fourth delay information for each second responding device to transmit a data frame to the first initiating device. Each of the plurality of data frames includes a time difference between the first responding device receiving N first UWB segment signals and the first responding device transmitting N second UWB segment signals or the first responding device transmitting N first orthogonal UWB segment signals. The first responding device is any one of M second responding devices.

[0016] It can be seen that the first initiating device can further receive the time difference between receiving and transmitting the UWB segment signals reported by the multiple second responding devices via a data frame at different times determined based on the fourth delay information for each second responding device. Thus, the first initiating device determines the distance measurement results for the multiple second responding devices based on the time difference between receiving and transmitting the UWB segment signals for the first initiating device, and the time difference between receiving and transmitting the UWB segment signals reported by the multiple second responding devices.

[0017] In one optional implementation, the first initiating device transmitting N first UWB segment signals separately based on the time-frequency position information of N first UWB segment signals includes, when the first timer has not expired and M response frames have been received, the first initiating device transmitting N first UWB segment signals separately based on the time-frequency position information of N first UWB segment signals, or when S response frames have been received and the first timer has expired, the first initiating device transmitting N first UWB segment signals separately based on the time-frequency position information of N first UWB segment signals. The first timer is triggered when the first initiating device transmits a polling frame, where S is an integer greater than or equal to 1 and less than M.

[0018] It is understood that the first initiating device triggers a first timer when it sends a polling frame. When the first initiating device receives response frames from all of the M second responding devices, it sends N first UWB segment signals separately, or when the first initiating device receives response frames from some of the M second responding devices and the first timer expires, it also sends N first UWB segment signals separately. Specifically, when some of the response frames have been received and the first timer expires, the first initiating device initiates the ranging round by directly sending N first UWB segment signals, without continuing to wait for responses from other second responding devices to the polling frame. This technique avoids ranging failures that would occur if the first initiating device were to indefinitely wait for responses from the second responding devices to the polling frame.

[0019] According to a second aspect, the application further provides a signal transmission method. The signal transmission method in this aspect corresponds to the signal transmission method in the first aspect. The signal transmission method in this aspect is described from the perspective of a first responding device. In this method, a first responding device receives a polling frame. The polling frame includes time-frequency position information of N first ultra-wideband (UWB) segment signals and first delay information for each of M second responding devices to reply to the first initiating device in a response frame, where N and M are integers of 2 or more. The first responding device is any one of the M second responding devices. The first responding device transmits a response frame to the first initiating device based on the timestamp of the polling frame and the first delay information for the first responding device to reply to the first initiating device in a response frame.

[0020] It is understood that, in this embodiment of the application, a polling frame received by any second responding device includes first delay information for the second responding device to reply to the polling frame from the first initiating device, so that any second responding device can reply to the first initiating device with a response frame at a time determined based on the first delay information for the second responding device. Thus, any second responding device can participate in a ranging round initiated by the first initiating device, thereby helping the first initiating device perform rangings on multiple second responding devices in a short amount of time, i.e., helping to improve ranging efficiency.

[0021] In one optional implementation, the polling frame further includes second delay information for each second responding device to respond to the first UWB segment signal from the first initiating device. Thus, the first responding device can further receive N first UWB segment signals separately based on the time-frequency position information of the N first UWB segment signals. The first responding device then transmits N second UWB segment signals separately to the first initiating device based on the second delay information for which the first responding device responds to the first UWB segment signal from the first initiating device.

[0022] What we can see is that if the polling frame further includes second delay information for each second responding device to reply to the first UWB segment signal from the first initiating device, any second responding device may further reply to the first initiating device with N second UWB segment signals based on the second delay information at different times, and as a result the first initiating device obtains the UWB segment signal used for distance measurement.

[0023] In one implementation of another option, the polling frame further includes identical third delay information for M second responding devices to reply to the first UWB segment signal from the first initiating device, and the orthogonal sequence index of each second responding device. Thus, the first responding device can further receive N first UWB segment signals separately based on the time-frequency position information of the N first UWB segment signals. The first responding device transmits N first orthogonal UWB segment signals separately to the first initiating device based on the third delay information. The first orthogonal UWB segment signals are determined based on the orthogonal sequence index of the first responding device.

[0024] It can be seen that any second responding device can reply to the first initiating device with N first orthogonal UWB segment signals at different times based on third delay information. Thus, different second responding devices can reply to the first initiating device with different first orthogonal UWB segment signals at the same time within the interval time of the N first UWB segment signals.

[0025] In one implementation of further alternative options, the polling frame further includes a fourth delay information for each second responding device to transmit a data frame to the first initiating device. Thus, the first responding device can further transmit a data frame to the first initiating device based on the fourth delay information for the first responding device to transmit a data frame to the first initiating device. The data frame includes a time difference between the first responding device receiving N first UWB segment signals and the first responding device transmitting N second UWB segment signals or the first responding device transmitting N first orthogonal UWB segment signals.

[0026] It can be understood that any second response device can further report to the first initiating device the time difference between receiving and transmitting a UWB segment signal at a time determined based on the fourth delay information. Therefore, by different second response devices transmitting data frames to the first initiating device at different times determined based on different fourth delay information, the time difference between receiving and transmitting a UWB segment signal for the first initiating device, and based on the time differences between receiving and transmitting a UWB segment signal reported by a plurality of second response devices, it can help the first initiating device perform ranging on a plurality of second response devices.

[0027] According to a third aspect, this application further provides a signal transmission method. In this method, a first initiating device transmits a polling frame. The polling frame includes the time-frequency position information of N first ultra-wideband (UWB) segment signals, the same response time for M second response devices to reply to the first initiating device in a response frame, and a sub-carrier set for all M second response devices to reply to the first initiating device in a response frame. The narrowband signal transmitted at the response time includes a plurality of sub-carriers. N and M are integers greater than or equal to 2. The first initiating device receives a response frame based on the response time and the sub-carrier set for all second response devices to reply to the first initiating device in a response frame, and the response frame includes a plurality of response signals.

[0028] It should be understood that, in this embodiment of this application, the polling frame transmitted by the first start device includes the same response time for M second response devices to reply to the first start device with a response frame, and a subcarrier set for all M second response devices to reply to the first start device with a response frame. Therefore, some or all of the M second response devices can reply to the first start device using response signals on different subcarrier sets at the above response time. Further, some or all of the M second response devices can participate in the ranging round of the first start device, thereby helping the first start device to perform ranging on a plurality of second response devices in a short time and helping to improve the ranging efficiency.

[0029] In one implementation of the option, the polling frame further includes second delay information for each second response device to reply to the first UWB segment signal from the first start device. Thus, the first start device can further transmit the N first UWB segment signals separately based on the time-frequency position information of the N first UWB segment signals. The first start device receives a plurality of second UWB segment signals separately based on the second delay information for each second response device to reply to the first UWB segment signal from the first start device.

[0030] It should be understood that the first start device starts a ranging round by transmitting the first UWB segment signal, and the first start device can receive the second UWB segment signals replied by a plurality of second response devices for all the first UWB segment signals at different times determined based on different second delay information. Therefore, the first start device performs ranging on a plurality of second start devices based on the plurality of transmitted first UWB signals and the plurality of received second UWB segment signals.

[0031] In one implementation of another option, the polling frame further includes identical third delay information for M second responding devices to respond to the first UWB segment signal from the first initiating device, and the orthogonal sequence index of each second responding device. Thus, the first initiating device can further transmit N first UWB segment signals separately based on the time-frequency position information of the N first UWB segment signals. The first initiating device receives multiple first orthogonal UWB segment signals separately based on the third delay information and the orthogonal sequence index of each second responding device.

[0032] It can be seen that a first initiating device initiates a ranging round by transmitting a first UWB segment signal, and the first initiating device can receive first orthogonal UWB segment signals, which are returned by multiple second responding devices in response to the first UWB segment signal, at the same time determined based on third delay information. The multiple first orthogonal UWB segment signals are orthogonal to each other. This scheme also helps the first initiating device perform ranging on multiple second initiating devices based on the multiple transmitted first UWB signals and the multiple received first orthogonal UWB segment signals.

[0033] In one optional implementation, if the polling frame further includes identical third delay information for M second responding devices to respond to a first UWB segment signal from a first initiating device, and an orthogonal sequence index for each second responding device, the first initiating device is active when it transmits N first UWB segment signals and receives a plurality of first orthogonal UWB segment signals, and idle during the interval time of the N first UWB segment signals other than the time of transmitting the N first UWB segment signals and the time of receiving the plurality of first orthogonal UWB segment signals.

[0034] Thus, the first start device can be active when it transmits N first UWB segment signals and receives multiple first orthogonal UWB segment signals, and can be idle for the remaining time in the interval between the N first UWB segment signals. Therefore, the active time of the first start device can be reduced, thereby reducing the power consumption of the first start device.

[0035] In one implementation of further alternative options, the polling frame further includes the same data frame time for all second responding devices to transmit the data frame to the first initiating device, and a set of subcarriers for all second responding devices to transmit the data frame to the first initiating device. Thus, the first initiating device can further receive the data frame based on the above data frame time and the set of subcarriers for all second responding devices to transmit the data frame to the first initiating device. The data frame includes a plurality of data signals. Each of the plurality of data signals includes a time difference between the first responding device receiving N first UWB segment signals and the first responding device transmitting N second UWB segment signals or the first responding device transmitting N first orthogonal UWB segment signals. The first responding device is any one of M second responding devices.

[0036] It can be seen that the first initiating device can further receive the time difference between receiving and transmitting the UWB segment signals reported by the multiple second responding devices via a data frame at different times determined based on a fourth delay information for each second responding device. This technique helps the first initiating device determine the ranging results for the multiple second responding devices based on the time difference between receiving and transmitting the UWB segment signals for the first initiating device, as well as the receive and transmit times reported by the multiple second responding devices.

[0037] According to a fourth aspect, the application further provides a signal transmission method. The signal transmission method in this aspect corresponds to the signal transmission method in the third aspect. The signal transmission method in this aspect is described from the perspective of a first responding device. In this method, a first responding device receives a polling frame. The polling frame includes time-frequency position information of N first ultra-wideband (UWB) segment signals, the same response time for M second responding devices to reply to the first initiating device in response frames, and a set of subcarriers for all of the M second responding devices to reply to the first initiating device in response frames. The narrowband signal transmitted during the response time includes multiple subcarriers, where N and M are integers of 2 or more. The first responding device transmits a response signal to the first initiating device based on the response time and the set of subcarriers for which the first responding device replies to the first initiating device in response frames. The first responding device is any one of the M second responding devices.

[0038] It is understood that in this embodiment of the application, any second response device can respond to the first initiator using a response frame on a subcarrier set for the second response device during the response time. Thus, any second response device can participate in the ranging round of the first initiator, thereby helping the first initiator perform ranging on multiple second response devices and improving ranging efficiency.

[0039] In one optional implementation, the polling frame further includes second delay information for each second responding device to respond to the first UWB segment signal from the first initiating device. Thus, the first responding device can further receive N first UWB segment signals separately based on the time-frequency position information of the N first UWB segment signals. The first responding device then transmits N second UWB segment signals separately to the first initiating device based on the second delay information for which the first responding device responds to the first UWB segment signal from the first initiating device.

[0040] In other optional implementations, the polling frame further includes second delay information for each second responding device to reply to the first UWB segment signal from the first initiating device. In this way, any second responding device can further reply to the first initiating device with N second UWB segment signals based on the second delay information, separately at different times, so that the first initiating device can obtain the UWB segment signals used for ranging. In one other optional implementation, the polling frame further includes the same third delay information for M second responding devices to reply to the first UWB segment signal from the first initiating device, and the orthogonal sequence index of each second responding device. Thus, the first responding device can further receive N first UWB segment signals separately based on the time-frequency position information of the N first UWB segment signals. The first responding device transmits N first orthogonal UWB segment signals separately to the first initiating device based on the third delay information. The first orthogonal UWB segment signal is determined based on the orthogonal sequence index of the first response device.

[0041] It can be seen that any second responding device can reply to the first initiating device with N first orthogonal UWB segment signals at different times based on third delay information. Thus, different second responding devices can reply to the first initiating device with different first orthogonal UWB segment signals at the same time within the interval time of the N first UWB segment signals.

[0042] In one optional implementation, the polling frame further includes the same data frame time for all second responding devices to transmit a data frame to the first initiating device, and a set of subcarriers for all second responding devices to transmit a data frame to the first initiating device. Thus, the first responding device further transmits a data signal to the first initiating device based on the data frame time and the set of subcarriers for the first responding device to transmit a data frame to the first initiating device. The data signal includes a time difference between the first responding device receiving N first UWB segment signals and the first responding device transmitting N second UWB segment signals or the first responding device transmitting N first orthogonal UWB segment signals.

[0043] It can be seen that any second responding device may further report to the first initiating device the time difference between receiving and transmitting the UWB segment signal at a time determined based on the fourth delay information. Thus, different second responding devices may transmit data frames to the first initiating device at different times determined based on different fourth delay information, which can help the first initiating device perform ranging to multiple second responding devices based on the time difference between receiving and transmitting the UWB segment signal for the first initiating device, and the time differences between receiving and transmitting the UWB segment signal reported by multiple second responding devices.

[0044] According to a fifth aspect, the application further provides a signal transmission method in which a control device transmits a polling frame, the polling frame comprising time-frequency position information of N ultra-wideband (UWB) segment signal groups, first delay information for each of M second response devices to reply to the control device in a response frame, and fifth delay information for each of X second initiating devices to reply to the control device in a response frame, where N, M, and X are integers of 2 or more. The control device receives a plurality of response frames based on a plurality of first delay information, a plurality of fifth delay information, and a timestamp of the polling frame.

[0045] It is understood that, in this embodiment of the application, the control device transmits a polling frame through which each of the X second initiating devices replies to the control device with a response frame and each of the M second responding devices replies to the control device with a response frame, so that some or all of the X second initiating devices may reply to the control device with a response frame at different times, and some or all of the M second responding devices may reply to the control device with a response frame at different times. Thus, multiple second initiating devices replying with response frames, and multiple second responding devices replying with response frames, participate in the same ranging round, thereby helping to perform ranging performed by multiple second initiating devices on multiple second responding devices, i.e., helping to improve ranging efficiency.

[0046] In one optional implementation, the polling frame further includes the orthogonal sequence index of each second initiating device, the orthogonal sequence index of each of the M second responding devices, and identical third delay information for all second responding devices to reply to the first initiating device with a third orthogonal UWB segment signal.

[0047] Thus, any second initiating device can separately transmit N second orthogonal UWB segment signals based on the time-frequency position information of N UWB segment signal groups and the orthogonal sequence index of the second initiating device. Consequently, any second responding device can separately receive multiple second orthogonal UWB segment signals based on the time-frequency position information of N UWB segment signal groups and the orthogonal sequence index of each second initiating device. Furthermore, any second responding device can transmit N third orthogonal UWB segment signals based on third delay information and the orthogonal sequence index of the second responding device. Consequently, any second initiating device can receive multiple third orthogonal UWB segment signals based on third delay information and the orthogonal sequence index of each second responding device.

[0048] In one implementation of another option, the polling frame further includes a fourth delay information for each second responding device to transmit a data frame to the second initiating device, so that any second responding device can transmit a data frame based on the fourth delay information for the second responding device. The data frame includes the time when the second responding device receives a second orthogonal UWB segment signal and the time when the second responding device transmits a third orthogonal UWB segment signal. Correspondingly, any first initiating device participating in the ranging round can receive multiple data frames based on the fourth delay information for each second responding device, and further perform ranging on multiple second responding devices based on the time information carried in those data frames.

[0049] According to a sixth aspect, the application further provides a signal transmission method. The signal transmission method in this aspect corresponds to the signal transmission method in the fifth aspect. The signal transmission method in this aspect is described from the perspective of a first initiator device. In this method, the first initiator device receives a polling frame which includes time-frequency position information of N ultra-wideband (UWB) segment signal groups and fifth delay information for each of X second initiators to reply to a control device in a response frame, the first initiator device being any one of the X second initiators, where N and X are integers of 2 or more. The first initiator device transmits a response frame based on the timestamp of the polling frame and the fifth delay information for the first initiator device to reply to the control device in a response frame.

[0050] It is understood that in this embodiment of the present application, a polling frame received by any second initiating device includes a fifth delay information for the initiating device to reply to the control device in a response frame, and as a result, any second initiating device can reply to the control device in a response frame based on the fifth delay information. Thus, any second initiating device can participate in a ranging round, and as a result, multiple initiating devices can participate in the same ranging round, thereby helping to improve ranging efficiency.

[0051] In one optional implementation, the polling frame further includes the orthogonal sequence index of each second initiating device, the orthogonal sequence index of each of the M second responding devices, and identical third delay information for all second responding devices to reply to the first UWB segment signal from the first initiating device, where M is an integer greater than or equal to 2. Thus, the first initiating device can further transmit N second orthogonal UWB segment signals separately based on the time-frequency position information of N UWB segment signal groups and the orthogonal sequence index of the first initiating device. The first initiating device receives a plurality of third orthogonal UWB segment signals separately based on the third delay information and the orthogonal sequence index of each second responding device.

[0052] It can be seen that any second initiating device can further transmit N second orthogonal UWB segment signals separately based on the orthogonal sequence index of the second initiating device and time-frequency position information of N UWB segment signal groups, and can receive a plurality of third orthogonal UWB segment signals separately based on third delay information and the orthogonal sequence index of each second responding device. Specifically, any second initiating device can perform distance measurement by transmitting second orthogonal UWB segment signals and receiving third orthogonal UWB segment signals.

[0053] In one implementation of another option, the polling frame further includes a fourth delay information for each second responding device to send a data frame to the second initiating device. Thus, the first initiating device can further receive a plurality of data frames based on the fourth delay information for each second responding device to send a data frame to the second initiating device. Each of the plurality of data frames includes the time for the first responding device to receive a plurality of second orthogonal UWB segment signals and the time for the first responding device to transmit a plurality of third orthogonal UWB segment signals. The first responding device is any one of M second responding devices.

[0054] It can be seen that any second initiating device can further separately receive the orthogonal UWB segment signal reception and transmission times reported by multiple second responding devices based on a fourth delay information for each responding device, and as a result, each second initiating device can perform distance measurements to the multiple second responding devices that reported the reception and transmission times based on the orthogonal UWB segment signal reception and transmission times.

[0055] According to a seventh aspect, the application further provides a signal transmission method. The signal transmission method in this aspect corresponds to the signal transmission methods in the fifth and sixth aspects. The signal transmission method in this aspect is described from the perspective of a first responding device. In this method, a first responding device receives a polling frame which includes time-frequency position information of N ultra-wideband (UWB) segment signal groups and first delay information for each of M second responding devices to reply to a control device in a response frame. The first responding device is any one of the M second responding devices, where N and X are integers greater than or equal to 2. The first responding device transmits a response frame based on the timestamp of the polling frame and the first delay information for the first responding device to reply to the control device in a response frame.

[0056] It is understood that in this embodiment of the present application, a polling frame received by any second responding device includes first delay information for the second responding device to reply to the control device in the response frame, so that any second responding device can reply to the control device in the response frame at different times, thereby helping multiple second responding devices participate in the same ranging round and helping to improve ranging efficiency.

[0057] In one optional implementation, the polling frame further includes the orthogonal sequence index of each of X second initiating devices, the orthogonal sequence index of each second responding device, and identical third delay information for all second responding devices to respond to the first UWB segment signal from the first initiating device, where X is an integer greater than or equal to 2. Thus, the second responding devices can further receive multiple second orthogonal UWB segment signals separately based on the time-frequency position information of N UWB segment signal groups and the orthogonal sequence indices of the X second initiating devices. The first responding device transmits multiple third orthogonal UWB segment signals separately based on the third delay information and the orthogonal sequence index of the first responding device.

[0058] In one optional implementation, the polling frame further includes a fourth delay information for each second responding device to transmit a data frame to the second initiating device. Thus, the first responding device can further transmit a data frame based on the fourth delay information for the first responding device to transmit a data frame to the second initiating device. The data frame includes the time for the first responding device to receive a plurality of second orthogonal UWB segment signals and the time for the first responding device to transmit a plurality of third orthogonal UWB segment signals.

[0059] According to the eighth aspect, the application further provides a signal transmission method, in which a control device transmits a polling frame, the polling frame comprising time-frequency position information of N ultra-wideband (UWB) segment signal groups, a first response time for X second initiating devices to reply to the control device in response frames, a subcarrier set for all X second initiating devices to reply to the control device in response frames, a second response time for M second responding devices to reply to the control device in response frames, and a subcarrier set for all M second responding devices to reply to the control device in response frames, where N, M, and X are integers of 2 or more. The control device receives a second response frame based on the same second response time for M second responding devices to reply to the control device in response frames and the subcarrier set for all second responding devices to reply to the control device in response frames, the second response frame comprising a plurality of second response signals. The control device receives a first response frame based on the same first response time for X second initiating devices to reply to the control device in response frames, and a set of subcarriers for all second initiating devices to reply to the control device in response frames, the first response frame comprising a plurality of first response signals.

[0060] It is understood that, in this embodiment of the present application, the control device transmits a polling frame, through which a first response time is configured for X second initiators to reply to the control device with response frames, and a subcarrier set for all X second initiators to reply to the control device with response frames; and a second response time is configured for M second response devices to reply to the control device with response frames, and a subcarrier set for all M second response devices to reply to the control device with response frames. Thus, a plurality of the X second initiators can reply to the control device with a first response signal at the first response time, and a plurality of the M second response devices can reply to the control device with a second response signal at the second response time. The first response signals replied by the plurality of second initiators are orthogonal to each other, and the second response signals replied by the plurality of second response devices are orthogonal to each other. Therefore, multiple second initiating devices that respond with response frames, and multiple second responding devices that respond with response frames, can participate in the same ranging round, thereby helping to perform ranging on multiple second responding devices by multiple second initiating devices, i.e., helping to improve ranging efficiency.

[0061] In one optional implementation, the polling frame further includes the orthogonal sequence index of each second initiating device, the orthogonal sequence index of each of the M second responding devices, and identical third delay information for all second responding devices to respond to the first UWB segment signal from the first initiating device.

[0062] In one implementation of another option, the polling frame further includes a data frame time during which M second responding devices transmit data frames to a second initiating device, and a set of subcarriers for all M second responding devices to transmit data frames to the second initiating device. Thus, different second responding devices can transmit data signals to the second initiating device on different subcarrier sets during the same data frame time, which are multiple data signals from the data frame. Each data signal includes a time difference between receiving and transmitting a UWB segment signal for the first responding device, and as a result, any second initiating device can perform ranging on multiple second responding devices based on the time carried in each data signal.

[0063] According to the ninth aspect, the application further provides a signal transmission method. The signal transmission method in this aspect corresponds to the signal transmission method in the eighth aspect. The signal transmission method in this aspect is described from the perspective of a first initiator device. In this method, the first initiator device receives a polling frame which includes time-frequency position information of N ultra-wideband (UWB) segment signal groups, the same first response time which X second initiators send back to the control device in response frames, and a set of subcarriers which all X second initiators send back to the control device in response frames, the first initiator device being any one of the X second initiators, where N and X are integers greater than or equal to 2. The second initiator device transmits a first response signal based on the first response time and the set of subcarriers which the first initiator device sends back to the control device in response frames.

[0064] It is understood that in this embodiment of the present application, a polling frame received by any second initiating device includes the time and subcarrier set for which the second initiating device replies to the control device with a first response signal, and as a result, multiple second initiating devices can participate in the same ranging round, thereby helping to perform ranging on multiple second initiating devices and helping to improve ranging efficiency.

[0065] In one optional implementation, the polling frame further includes the orthogonal sequence index of each second initiating device, the orthogonal sequence index of each of the M second responding devices, and identical third delay information for all second responding devices to reply to the first UWB segment signal from the second initiating device, where M is an integer greater than or equal to 2. Thus, the first initiating device can further transmit N second orthogonal UWB segment signals separately based on the time-frequency position information of N first UWB segment signal groups and the orthogonal sequence index of the first initiating device. The first initiating device receives a plurality of third orthogonal UWB segment signals separately based on the third delay information and the orthogonal sequence index of each second responding device.

[0066] In one optional implementation, the polling frame further includes the same data frame time during which all second responding devices transmit data frames to the first initiating device, and a set of subcarriers for all second responding devices to transmit data frames to the first initiating device. Thus, the first initiating device can further receive a data frame based on the above data frame time and the set of subcarriers for all second responding devices to transmit data frames to the first initiating device. The data frame includes a plurality of data signals, each of which includes the time during which the first responding device receives a plurality of second orthogonal UWB segment signals, and the time during which the first responding device transmits a plurality of third orthogonal UWB segment signals. The first responding device is any one of M second responding devices.

[0067] According to the tenth aspect, the application further provides a signal transmission method. The signal transmission method in this aspect corresponds to the signal transmission methods in the eighth and ninth aspects. The signal transmission method in this aspect is described from the perspective of a first responding device. In this method, the first responding device receives a polling frame which includes time-frequency position information of N ultra-wideband (UWB) segment signal groups, the same second response time which M second responding devices send back to the control device in response frames, and a set of subcarriers which all M second responding devices send back to the control device in response frames. N and M are integers greater than or equal to 2. The first responding device is any one of the M second responding devices. The first responding device transmits a second response signal based on the second response time and the set of subcarriers which the first responding device sends back to the control device in response frames.

[0068] It is understood that in this embodiment of the present application, a polling frame received by any second response device includes the time and subcarrier set for which the second response device replies to the control device with a second response signal, and as a result, multiple second response devices can participate in the same ranging round, thereby helping to perform ranging on multiple second response devices and improving ranging efficiency.

[0069] In one optional implementation, the polling frame further includes the orthogonal sequence index of each of X second initiating devices, the orthogonal sequence index of each second responding device, and identical third delay information for all second responding devices to respond to the first UWB segment signal from the first initiating device. The first initiating device is any one of the X second initiating devices, where X is an integer greater than or equal to 2. Thus, the first responding device can further receive multiple second orthogonal UWB segment signals based on the time-frequency position information of N UWB segment signal groups and the orthogonal sequence index of each second initiating device. The first responding device transmits multiple third orthogonal UWB segment signals separately based on the third delay information and the orthogonal sequence index of the first responding device.

[0070] In one implementation of another option, the polling frame further includes the same data frame time for all second responding devices to transmit data frames to the first initiating device, and a set of subcarriers for all second responding devices to transmit data frames to the first initiating device. Thus, the first responding device may further transmit a data signal based on the data frame time and the set of subcarriers for the first responding device to transmit data frames to the first initiating device, the data signal including the time for the first responding device to receive a plurality of second orthogonal UWB segment signals and the time for the first responding device to transmit a plurality of third orthogonal UWB segment signals.

[0071] According to the eleventh aspect, the application further provides a communication device having some or all of the functions to implement a first initiator device according to the first, third, sixth, and ninth aspects, or some or all of the functions to implement a first response device according to the second, fourth, seventh, and tenth aspects, or some or all of the functions to implement a control device according to the fifth or eighth aspect. For example, the functions of the communication device may include some or all of the functions in an embodiment of the first initiator device according to the first aspect of this application, or may have functions to independently implement any embodiment of the embodiments of this application. The functions may be implemented using hardware, or by using hardware that runs corresponding software. The hardware or software includes one or more units or modules corresponding to the functions described above.

[0072] In one possible design, the communication device may include a processing unit and a communication unit. The processing unit is configured to support the communication device when performing the corresponding functions in the manner described above. The communication unit is configured to support communication between the communication device and other communication devices. The communication device may further include a storage unit. The storage unit is configured to be coupled with the processing unit and the communication unit and stores the program instructions and data required for the communication device.

[0073] In one implementation, the communication device includes a processing unit and a communication unit. The processing unit is configured to control the communication unit to perform data / signaling reception and transmission. The communication unit is configured to transmit a polling frame. The polling frame includes time-frequency position information for N first ultra-wideband (UWB) segment signals and first delay information for each of M second responding devices to reply to the first initiating device in a response frame, where N and M are integers of 2 or greater. The communication unit is further configured to receive a plurality of response frames based on the timestamp of the polling frame and the first delay information for each second responding device to reply to the first initiating device in a response frame.

[0074] For other optional implementations of the communication device in this embodiment, please refer to the relevant content in the first embodiment. Details will not be explained again here.

[0075] In another implementation, the communication device includes a processing unit and a communication unit. The processing unit is configured to control the communication unit to perform data / signaling reception and transmission. The communication unit is configured to receive a polling frame. The polling frame has time-frequency position information for N first ultra-wideband (UWB) segment signals and first delay information for each of M second responding devices to reply to the first initiating device in a response frame, where N and M are integers greater than or equal to 2, and the first responding device is any one of the M second responding devices. The communication unit is further configured to send a response frame to the first initiating device based on the timestamp of the polling frame and the first delay information for the first responding device to reply to the first initiating device in a response frame.

[0076] Furthermore, for other optional implementations of the communication device in this embodiment, please refer to the relevant content in the second embodiment. Details will not be explained again here.

[0077] In yet another implementation, the communication device includes a processing unit and a communication unit. The processing unit is configured to control the communication unit to perform data / signaling reception and transmission. The communication unit is configured to transmit a polling frame. The polling frame includes time-frequency position information of N first ultra-wideband (UWB) segment signals, the same response time for M second responding devices to reply to the first initiating device in response frames, and a set of subcarriers for all M second responding devices to reply to the first initiating device in response frames, wherein the narrowband signal transmitted during the response time includes multiple subcarriers, and N and M are integers greater than or equal to 2. The communication unit is further configured to receive a response frame based on the response time and the set of subcarriers for all second responding devices to reply to the first initiating device in response frames, wherein the response frame includes multiple response signals.

[0078] Furthermore, for other optional implementations of the communication device in this embodiment, please refer to the relevant content in the third embodiment. Details will not be explained again here.

[0079] In yet another implementation, the communication device includes a processing unit and a communication unit. The processing unit is configured to control the communication unit to perform data / signaling reception and transmission. The communication unit is configured to receive a polling frame. The polling frame includes time-frequency position information of N first ultra-wideband (UWB) segment signals, the same response time for M second responding devices to reply to the first initiating device in a response frame, and a set of subcarriers for all of the M second responding devices to reply to the first initiating device in a response frame, wherein the narrowband signal transmitted in the response time includes multiple subcarriers, and N and M are integers greater than or equal to 2. The communication unit is further configured to transmit a response signal to the first initiating device based on the response time and the set of subcarriers for the first responding devices to reply to the first initiating device in a response frame, wherein the first responding device is any one of the M second responding devices.

[0080] Furthermore, for other optional implementations of the communication device in this embodiment, please refer to the relevant content in the fourth embodiment. Details will not be explained again here.

[0081] In yet another implementation, the communication device includes a processing unit and a communication unit. The processing unit is configured to control the communication unit to perform data / signaling reception and transmission. The communication unit transmits a polling frame. The polling frame includes time-frequency position information for N ultra-wideband (UWB) segment signal groups, first delay information for each of M second responding devices to reply to the control device in a response frame, and fifth delay information for each of X second initiating devices to reply to the control device in a response frame, where N, M, and X are integers greater than or equal to 2. The communication unit is further configured to receive a plurality of response frames based on a plurality of first delay information, a plurality of fifth delay information, and a timestamp of the polling frame.

[0082] Furthermore, for other optional implementations of the communication device in this embodiment, please refer to the relevant content in Embodiment 5. Details will not be explained again here.

[0083] In yet another implementation, the communication device includes a processing unit and a communication unit. The processing unit is configured to control the communication unit to perform data / signaling reception and transmission. The communication unit is configured to receive a polling frame. The polling frame includes time-frequency position information for N ultra-wideband (UWB) segment signal groups and fifth delay information for each of X second initiating devices to reply to the control device in a response frame, where the first initiating device is any one of the X second initiating devices, and N and X are integers greater than or equal to 2. The communication unit is further configured to transmit a response frame based on the timestamp of the polling frame and the fifth delay information for the first initiating device to reply to the control device in a response frame.

[0084] Furthermore, for other optional implementations of the communication device in this embodiment, please refer to the relevant content in Embodiment 6. Details will not be explained again here.

[0085] In yet another implementation, the communication device includes a processing unit and a communication unit. The processing unit is configured to control the communication unit to perform data / signaling reception and transmission. The communication unit is configured to receive polling frames. The polling frame includes time-frequency position information for N ultra-wideband (UWB) segment signal groups and first delay information for each of M second responding devices to reply to the control device in a response frame, where the first responding device is any one of the M second responding devices, and N and M are integers greater than or equal to 2. The communication unit is further configured to transmit a response frame based on the timestamp of the polling frame and the first delay information for the first responding device to reply to the control device in a response frame.

[0086] For other optional implementations of the communication device in this embodiment, please refer to the relevant content in Embodiment 7. Details will not be explained again here.

[0087] In yet another implementation, the communication device includes a processing unit and a communication unit. The processing unit is configured to control the communication unit to perform data / signaling reception and transmission. The communication unit is configured to transmit a polling frame. The polling frame includes time-frequency position information for N ultra-wideband (UWB) segment signal groups, identical second response times for M second responding devices to return to the control device in response frames, a set of subcarriers for all M second responding devices to return to the control device in response frames, identical first response times for X second initiating devices to return to the control device in response frames, and a set of subcarriers for all X second initiating devices to return to the control device in response frames, wherein the narrowband signal transmitted in response time includes multiple subcarriers, and N, M, and X are integers greater than or equal to 2.

[0088] The communication unit is further configured to receive a second response frame based on M second response devices sending back a response frame to the control device, and a set of subcarriers for all second response devices to send back a response frame to the control device, the second response frame comprising a plurality of second response signals. The communication unit is further configured to receive a first response frame based on X second initiating devices sending back a response frame to the control device, and a set of subcarriers for all second initiating devices to send back a response frame to the control device, the first response frame comprising a plurality of first response signals.

[0089] Furthermore, for other optional implementations of the communication device in this embodiment, please refer to the relevant content in Embodiment 8. Details will not be explained again here.

[0090] In yet another implementation, the communication device includes a processing unit and a communication unit. The processing unit is configured to control the communication unit to perform data / signaling reception and transmission. The communication unit is configured to receive polling frames. The polling frame includes time-frequency position information for N ultra-wideband (UWB) segment signal groups, the same first response time for X second initiating devices to reply to the control device in response frames, and a set of subcarriers for all X second initiating devices to reply to the control device in response frames, where the first initiating device is any one of the X second initiating devices, and N and X are integers greater than or equal to 2.

[0091] The communication unit is further configured to transmit a first response signal based on a first response time and a set of subcarriers for the first initiating device to reply to the control device in a response frame.

[0092] Furthermore, for other optional implementations of the communication device in this embodiment, please refer to the relevant content in Embodiment 9. Details will not be explained again here.

[0093] In yet another implementation, the communication device includes a processing unit and a communication unit. The processing unit is configured to control the communication unit to perform data / signaling reception and transmission. The communication unit is configured to receive a polling frame. The polling frame includes time-frequency position information of N ultra-wideband (UWB) segment signal groups, identical second response times for M second responding devices to reply to the control device in response frames, and a set of subcarriers for all M second responding devices to reply to the control device in response frames, where N and M are integers greater than or equal to 2, and the first responding device is any one of the M second responding devices. The communication unit is further configured to transmit a second response signal based on the second response times and the set of subcarriers for the first responding devices to reply to the control device in response frames.

[0094] Furthermore, for other optional implementations of the communication device in this embodiment, please refer to the relevant content in Embodiment 10. Details will not be explained again here.

[0095] In one example, the communication unit may be a transceiver or a communication interface, the storage unit may be memory, and the processing unit may be a processor.

[0096] In one implementation, the communication device includes a processor and a transceiver. The processor is configured to control the transceiver to perform data / signaling reception and transmission. The transceiver is configured to transmit a polling frame. The polling frame includes time-frequency position information for N first ultra-wideband (UWB) segment signals and first delay information for each of M second responding devices to reply to the first initiating device in a response frame, where N and M are integers of 2 or greater. The transceiver is further configured to receive a plurality of response frames based on the timestamp of the polling frame and the first delay information for each second responding device to reply to the first initiating device in a response frame.

[0097] For other optional implementations of the communication device in this embodiment, please refer to the relevant content in the first embodiment. Details will not be explained again here.

[0098] In another implementation, the communication device includes a processor and a transceiver. The processor is configured to control the transceiver to perform data / signaling reception and transmission. The transceiver receives a polling frame. The polling frame has time-frequency position information for N first ultra-wideband (UWB) segment signals and first delay information for each of M second responding devices to reply to the first initiating device in a response frame, where N and M are integers greater than or equal to 2, and the first responding device is any one of the M second responding devices. The transceiver is further configured to send a response frame to the first initiating device based on the timestamp of the polling frame and the first delay information for the first responding device to reply to the first initiating device in a response frame.

[0099] Furthermore, for other optional implementations of the communication device in this embodiment, please refer to the relevant content in the second embodiment. Details will not be explained again here.

[0100] In yet another implementation, the communication device includes a processor and a transceiver. The processor is configured to control the transceiver to perform data / signaling reception and transmission. The transceiver is configured to transmit a polling frame. The polling frame includes time-frequency position information of N first ultra-wideband (UWB) segment signals, identical response times for M second responding devices to reply to the first initiating device in response frames, and a set of subcarriers for all M second responding devices to reply to the first initiating device in response frames, wherein the narrowband signal transmitted during the response time includes multiple subcarriers, and N and M are integers greater than or equal to 2. The transceiver is further configured to receive a response frame based on the response time and the set of subcarriers for all second responding devices to reply to the first initiating device in response frames, wherein the response frame includes multiple response signals.

[0101] Furthermore, for other optional implementations of the communication device in this embodiment, please refer to the relevant content in the third embodiment. Details will not be explained again here.

[0102] In yet another implementation, the communication device includes a processor and a transceiver. The processor is configured to control the transceiver to perform data / signaling reception and transmission. The transceiver is configured to receive a polling frame. The polling frame includes time-frequency position information of N first ultra-wideband (UWB) segment signals, the same response time for M second responding devices to reply to the first initiating device in a response frame, and a set of subcarriers for all of the M second responding devices to reply to the first initiating device in a response frame, wherein the narrowband signal transmitted during the response time includes multiple subcarriers, and N and M are integers greater than or equal to 2. The transceiver is further configured to transmit a response signal to the first initiating device based on the response time and the set of subcarriers for the first responding devices to reply to the first initiating device in a response frame, wherein the first responding device is any one of the M second responding devices.

[0103] Furthermore, for other optional implementations of the communication device in this embodiment, please refer to the relevant content in the fourth embodiment. Details will not be explained again here.

[0104] In yet another implementation, the communication device includes a processor and a transceiver. The processor is configured to control the transceiver to perform data / signaling reception and transmission. The transceiver is configured to transmit a polling frame. The polling frame includes time-frequency position information for N ultra-wideband (UWB) segment signal groups, first delay information for each of M second responding devices to reply to the control device in a response frame, and fifth delay information for each of X second initiating devices to reply to the control device in a response frame, where N, M, and X are integers greater than or equal to 2. The transceiver is further configured to receive a plurality of response frames based on a plurality of first delay information, a plurality of fifth delay information, and a timestamp of the polling frame.

[0105] Furthermore, for other optional implementations of the communication device in this embodiment, please refer to the relevant content in Embodiment 5. Details will not be explained again here.

[0106] In yet another implementation, the communication device includes a processor and a transceiver. The processor is configured to control the transceiver to receive and transmit data / signaling. The transceiver is configured to receive a polling frame. The polling frame includes time-frequency position information for N ultra-wideband (UWB) segment signal groups and fifth delay information for each of X second initiating devices to reply to the control device in a response frame, where the first initiating device is any one of the X second initiating devices, and N and X are integers greater than or equal to 2. The transceiver is further configured to transmit a response frame based on the timestamp of the polling frame and the fifth delay information for the first initiating device to reply to the control device in a response frame.

[0107] Furthermore, for other optional implementations of the communication device in this embodiment, please refer to the relevant content in Embodiment 6. Details will not be explained again here.

[0108] In yet another implementation, the communication device includes a processor and a transceiver. The processor is configured to control the transceiver to receive and transmit data / signaling. The transceiver is configured to receive a polling frame. The polling frame includes time-frequency position information for N ultra-wideband (UWB) segment signal groups and first delay information for each of M second responding devices to reply to the control device in a response frame, where the first responding device is any one of the M second responding devices, and N and M are integers greater than or equal to 2. The transceiver is further configured to transmit a response frame based on the timestamp of the polling frame and the first delay information for the first responding device to reply to the control device in a response frame.

[0109] For other optional implementations of the communication device in this embodiment, please refer to the relevant content in Embodiment 7. Details will not be explained again here.

[0110] In yet another implementation, the communication device includes a processor and a transceiver. The processor is configured to control the transceiver to perform data / signaling reception and transmission. The transceiver is configured to transmit a polling frame. The polling frame includes time-frequency position information for N ultra-wideband (UWB) segment signal groups, identical second response times for M second responding devices to reply to the control device in response frames, a set of subcarriers for all M second responding devices to reply to the control device in response frames, identical first response times for X second initiating devices to reply to the control device in response frames, and a set of subcarriers for all X second initiating devices to reply to the control device in response frames, wherein the narrowband signal transmitted in response time includes multiple subcarriers, and N, M, and X are integers greater than or equal to 2.

[0111] The transceiver is further configured to receive a second response frame based on M second response devices sending back a response frame to the control device, and a set of subcarriers for all second response devices to send back a response frame to the control device, the second response frame comprising a plurality of second response signals. The transceiver is further configured to receive a first response frame based on X second initiating devices sending back a response frame to the control device, and a set of subcarriers for all second initiating devices to send back a response frame to the control device, the first response frame comprising a plurality of first response signals.

[0112] Furthermore, for other optional implementations of the communication device in this embodiment, please refer to the relevant content in Embodiment 8. Details will not be explained again here.

[0113] In yet another implementation, the communication device includes a processor and a transceiver. The processor is configured to control the transceiver to perform data / signaling reception and transmission. The transceiver is configured to receive a polling frame. The polling frame includes time-frequency position information of N ultra-wideband (UWB) segment signal groups, the same first response time for X second initiating devices to reply to the control device in response frames, and a set of subcarriers for all X second initiating devices to reply to the control device in response frames, where the first initiating device is any one of the X second initiating devices, and N and X are integers greater than or equal to 2. The transceiver is further configured to transmit a first response signal based on the first response time and the set of subcarriers for the first initiating devices to reply to the control device in response frames.

[0114] Furthermore, for other optional implementations of the communication device in this embodiment, please refer to the relevant content in Embodiment 9. Details will not be explained again here.

[0115] In yet another implementation, the communication device includes a processor and a transceiver. The processor is configured to control the transceiver to receive and transmit data / signaling. The transceiver is configured to receive a polling frame. The polling frame includes time-frequency position information for N ultra-wideband (UWB) segment signal groups, identical second response times for M second responding devices to reply to the control device in response frames, and a set of subcarriers for all M second responding devices to reply to the control device in response frames, where N and M are integers greater than or equal to 2, and the first responding device is any one of the M second responding devices. The transceiver is further configured to transmit a second response signal based on the second response times and the set of subcarriers for the first responding devices to reply to the control device in response frames.

[0116] Furthermore, for other optional implementations of the communication device in this embodiment, please refer to the relevant content in Embodiment 10. Details will not be explained again here.

[0117] In another implementation, the communication device is a chip or a chip system. The processing unit may also be represented as a processing circuit or a logic circuit. The communication unit may be an input / output interface, interface circuit, output circuit, input circuit, pin, associated circuit, or similar on the chip or chip system.

[0118] In the implementation process, the processor may be configured to perform baseband-related processing, for example, but not limited to the following, and the transceiver may be configured to perform radio frequency reception and transmission, for example, but not limited to the following. The above components may be located separately on multiple independent chips, or at least some or all of them may be located on the same chip. For example, the processor may be further divided into an analog baseband processor and a digital baseband processor. The analog baseband processor and the transceiver may be integrated on the same chip, while the digital baseband processor may be located on a separate chip. With the continuous development of integrated circuit technology, more components may be integrated on the same chip. For example, a digital baseband processor and multiple application processors (for example, graphics processing units and multimedia processors, for example, but not limited to the following) may be integrated on the same chip. Such a chip is sometimes called a system-on-a-chip (SoC). Whether components are located separately on different chips or integrated on one or more chips usually depends on the requirements of the product design. The implementation forms of the above components are not limited to the embodiments of this application.

[0119] According to a twelfth aspect, the application further provides a processor configured to perform the methods described above. In the process of performing these methods, the process of transmitting the information described above and the process of receiving the information described above may be understood as a process of outputting the information described above by the processor and a process of receiving the input information described above by the processor. When outputting the information described above, the processor outputs the information described above to a transceiver so that the transceiver transmits the information. After the information described above is output by the processor, further processing of the information may need to be performed on the information before it arrives at the transceiver. Similarly, in the reception of the input information described above by the processor, the transceiver receives the information described above and inputs the information described above to the processor. Also, after the transceiver receives the information described above, further processing of the information may need to be performed on the information before it is input to the processor.

[0120] Based on the principles described above, for example, sending a polling frame as described in the above method may be understood as the processor outputting a polling frame.

[0121] Unless otherwise stated, or if the operations such as transmission and reception related to the processor do not contradict the actual function or internal logic of the operations in the relevant description, all operations may be more generally understood as the outputs, receptions, and inputs of the processor, rather than the transmission and reception operations directly performed by the radio frequency circuit and antenna.

[0122] In the implementation process, the processor may be a processor specifically configured to perform these methods, or it may be a processor that performs these methods by executing computer instructions in memory, such as a general-purpose processor. The memory may be non-transitory memory, such as read-only memory (ROM). The memory and processor may be integrated on the same chip or arranged separately on different chips. The type of memory and the arrangement of the memory and processor are not limited to the embodiments of this application.

[0123] According to a thirteenth aspect, the application further provides a communication system comprising at least one first initiating device and at least two first responding devices as described in the above aspects. In one other possible design, the system may further include another device that interacts with the first initiating device and the first responding devices in the solution provided in the application.

[0124] According to the fourteenth aspect, the application provides a computer-readable storage medium configured to store instructions. When the instructions are executed by a computer, a method according to any of the first to tenth aspects is carried out.

[0125] According to the 15th aspect, the application further provides a computer program product including instructions. When the computer program product is executed on a computer, a method according to any of the first to tenth aspects is carried out.

[0126] According to the 16th aspect, the application provides a chip system. The chip system includes a processor and an interface, the interface being configured to acquire a program or instruction, and the processor being configured to implement or support a second communication device in performing a function in any of the first to tenth aspects, such as calling the program or instruction and determining or processing at least one of the data and information in the manner described above. In one possible design, the chip system further includes memory, the memory being configured to store program instructions and data required by a terminal. The chip system may include a chip, or it may include a chip and another discrete component. [Brief explanation of the drawing]

[0127] [Figure 1(a)] This is a diagram showing the configuration of a system architecture according to one embodiment of this application. [Figure 1(b)] This is a diagram showing the configuration of another system architecture according to one embodiment of this application. [Figure 2(a)] This is a diagram illustrating a distance measurement procedure for one-sided bidirectional distance measurement according to one embodiment of this application. [Figure 2(b)] This is a diagram illustrating a distance measurement procedure for bidirectional distance measurement according to one embodiment of this application. [Figure 3] This is a diagram showing the configuration of a UWB segment signal according to one embodiment of this application. [Figure 4] This is a diagram illustrating a one-to-one distance measurement procedure according to one embodiment of this application. [Figure 5] This is a schematic interaction flowchart of a signal transmission method according to one embodiment of this application. [Figure 6] This is a diagram of a distance measurement procedure according to one embodiment of this application. [Figure 7] This is a diagram of another distance measuring procedure according to one embodiment of this application. [Figure 8]This is a schematic interaction flowchart of another signal transmission method according to one embodiment of this application. [Figure 9] This is a diagram of yet another ranging procedure according to one embodiment of this application. [Figure 10] This is a diagram of yet another ranging procedure according to one embodiment of this application. [Figure 11] This is a schematic interaction flowchart of further other signal transmission methods according to one embodiment of this application. [Figure 12] This is a diagram of yet another ranging procedure according to one embodiment of this application. [Figure 13A] Figures 13A and 13B are schematic interaction flowcharts of further other signal transmission methods according to one embodiment of this application. [Figure 13B] Figures 13A and 13B are schematic interaction flowcharts of further other signal transmission methods according to one embodiment of this application. [Figure 14] This is a diagram of yet another ranging procedure according to one embodiment of this application. [Figure 15] This is a diagram showing the configuration of a communication device according to one embodiment of this application. [Figure 16] This is a diagram showing the configuration of another communication device according to one embodiment of this application. [Figure 17] This is a diagram of the configuration of a chip according to one embodiment of this application. [Modes for carrying out the invention]

[0128] The technical solutions in the embodiments of this application will be described clearly and completely below with reference to the accompanying drawings.

[0129] 1. System Architecture

[0130] To better understand the signal transmission method disclosed in the embodiments of this application, a system architecture to which the embodiments of this application can be applied will be described.

[0131] Figures 1(a) and 1(b) show system architectures to which embodiments of this application can be applied. Both Figures 1(a) and 1(b) include fully functional and reduced functional devices. Figure 1(a) shows a star topology system architecture. In this architecture, a central control node communicates data with one or more other nodes. Figure 1(b) shows a peer-to-peer topology system configuration. In this architecture, the central control node can communicate data with one or more other nodes, and other different nodes can also communicate data with each other.

[0132] In embodiments of this application, the nodes in Figures 1(a) and 1(b) include, but are not limited to, a central control point such as a communication server, router, switch, network bridge, computer, mobile phone, other network devices, and other terminal devices, a personal area network (PAN), and a PAN coordinator.

[0133] It should be understood that the wireless communication systems in embodiments of this application include, but are not limited to, three application scenarios: narrowband internet of things (NB-IoT) systems, long-term evolution (LTE) systems, and 5G mobile communication systems, namely enhanced mobile broadband (eMBB), ultra-reliable low-latency communication (URLLC), and massive machine-type communications (mMTC), wireless fidelity (Wi-Fi) systems, or 5G and later mobile communication systems.

[0134] The network device in this embodiment of the application is a device having wireless transceiver functionality, configured to communicate with a terminal device, and may be an evolved Node B (eNB or eNodeB) in LTE, a base station in a 5G network, a base station in a future advanced public land mobile network (PLMN), a broadband network gateway (BNG), an aggregation switch, a 3rd generation partnership project (3GPP) access device, or similar. Optionally, the network devices in embodiments of this application may include various forms of base stations, such as macro base stations, micro base stations (also known as small cells), relay stations, access points, devices for implementing base station functions in the future, access nodes in Wi-Fi systems, transmitting and receiving points (TRPs), transmitting points (TPs), mobile switching centers, and devices that function as base stations in communications such as device-to-device (D2D), vehicle-to-everything (V2X), and machine-to-machine (M2M). This is not particularly limited to embodiments of this application.

[0135] The terminal devices in the embodiments of this application may include various handheld devices, in-vehicle devices, wearable devices, or computing devices having wireless communication capabilities, or other processing devices connected to a wireless modem. Terminal devices also include user equipment (UE), access terminals, subscriber units, user agents, cellular phones, smartphones, wireless data cards, personal digital assistants (PDAs), tablet computers, wireless modems, handheld devices (handsets), laptop computers, machine-type communication (MTC) terminals, communication devices carried on high-altitude aircraft, wearable devices, unmanned aerial vehicles, robots, terminals in device-to-device (D2D) communication, terminals in vehicle-to-everything (V2X), terminal devices in virtual reality (VR), terminal devices in augmented reality (AR), wireless terminals in industrial control, wireless terminals in self-driving, wireless terminals in remote medical care, and smart grids. This may also refer to wireless terminals in grids, wireless terminals in transportation safety, wireless terminals in smart cities, wireless terminals in smart homes, terminal devices in future communication networks, or similar devices. This is not limited to these in this application.

[0136] To facilitate understanding of the embodiments disclosed in this application, the following two points will be explained.

[0137] (1) In the embodiments disclosed in this application, an example is used in which the scenario is a 5G new radio (NR) network scenario in a wireless communication network. The solutions in the embodiments disclosed in this application can also be applied to other wireless communication networks, and the corresponding names can be replaced with the names of the corresponding functions in other wireless communication networks.

[0138] (2) All aspects, embodiments, or features of this application are presented by describing systems, in the embodiments disclosed herein, that include a plurality of devices, components, and modules, etc. It should be recognized and understood that each system may include other devices, components, and modules, etc., and / or may not include all of the devices, components, and modules, etc., described with reference to the accompanying drawings. Alternatively, combinations of these solutions may be used.

[0139] Ultra-wideband (UWB) technology is a wireless carrier communication technology. In this technology, data transmission is performed through narrow, non-sinusoidal pulses at the nanosecond level, so that a wide spectral range is occupied. In ranging, the accuracy of measurement or sensing is related to the signal bandwidth. A larger signal bandwidth results in higher accuracy sensing or ranging. Therefore, it has been proposed to use UWB solutions for ranging to improve the accuracy of ranging and sensing.

[0140] Currently, methods for performing ranging measurements on multiple nodes from a single node include single-sided two-way ranging (SS-TWR) and double-sided two-way ranging (DS-TWR). The procedure for performing SS-TWR ranging measurements on multiple nodes from a single node is shown in Figure 2(a). The initiator broadcasts a UWB signal #a used for ranging. Responders 1 through n receive the UWB signal #a, and respond to the UWB signal #a from the initiator through scheduling or contention; that is, responders 1 through n respond to the initiator with UWB signals #1 through #n, respectively. The UWB signal returned by each responder carries the time the responder received the UWB signal #a and the time the responder returned the UWB signal. For example, in the case of responder #1, the UWB signal #1 returned by responder #1 carries the time when responder #1 received UWB signal #a and the time when responder #1 transmitted UWB signal #1. Therefore, the initiator can calculate the time of flight (TOF) between the initiator and each responder based on the receive and transmit times carried in the UWB signal returned by each responder, and the UWB signal receive and transmit times for the initiator, thereby completing the ranging for multiple responders.

[0141] Figure 2(b) shows the procedure for performing DS-TWR ranging on multiple nodes using a single node. As can be seen by comparing it with Figure 2(a), the difference between the DS-TWR ranging procedure and the SS-TWR ranging procedure is that after receiving the UWB signal returned by each responder, the initiator broadcasts UWB signal #a again, and this UWB signal #a carries the time when the initiator received the UWB signal returned by each responder and the time when the initiator transmitted the UWB signal #a. Thus, after receiving the UWB signal #a, each responder can calculate the TOF between the responder and the initiator based on the UWB signal reception and transmission times for the responder. Therefore, not only can the initiator complete ranging on each responder, but each responder can also complete ranging on the initiator, i.e., two-way ranging is implemented.

[0142] However, because the bandwidth of UWB systems is excessively large, the Federal Communications Commission imposes strict limits on the power spectral density of UWB signals to suppress interference to other narrowband devices caused by operating UWB systems. In one embodiment, the total energy of UWB signals transmitted within 1 millisecond in a 500 MHz bandwidth is limited to 37 nJ, and this limit reduces the coverage of UWB signals. In other words, when ranging is performed using the UWB signals shown in Figures 2(a) and 2(b), the coverage of the UWB signals is low. As a result, the signal-to-noise ratio of the UWB signals received at the receiving end is low, further affecting ranging performance.

[0143] Therefore, in order to improve the instantaneous power of the transmitted signal, increase the coverage of the UWB signal, and increase the signal-to-noise ratio of the UWB signal received at the receiving end, it is proposed that the energy of the UWB signal be transmitted together in a shorter time. Based on this, in some scenarios where increased transmission power is required, the transmitting end divides the UWB signal to be transmitted into multiple segments, with each UWB segment signal having a time length of less than 1 millisecond. For example, in Figure 3, the divided UWB segment signals include UWB segment signal 1, UWB segment signal 2, and UWB segment signal 3, and the transmitting end transmits only one of these UWB segment signals within each millisecond.

[0144] Currently, Figure 4 shows the procedure for performing distance measurement between one node and another based on UWB segment signals. When the initiator performs distance measurement on the responder, it involves multiple ranging blocks, one of which includes an active ranging round.

[0145] In an active ranging round, the initiator transmits a polling frame using a narrowband signal, which contains time-frequency position information for multiple UWB segment signals #1. When a responder receives a polling frame and decides to participate in the initiator's ranging round, the responder replies to the initiator with a response frame, which carries time-frequency position information for replying to the initiator with multiple UWB segment signals #2. The process of the initiator transmitting a polling frame and the responder replying with a response frame is a negotiation phase in the ranging round, where the initiator and responder negotiate time-frequency position information for transmitting multiple UWB segment signals #1 and time-frequency position information for replying with multiple UWB segment signals #2. Based on the time-frequency position information for multiple UWB segment signals #1, the initiator transmits multiple UWB segment signals #1 separately. The responder receives multiple UWB segment signals #1 separately based on their time-frequency position information. The responder replies with multiple UWB segment signals #2 separately based on their time-frequency position information. The initiator receives multiple UWB segment signals #2 separately based on their time-frequency position information. Finally, the responder reports to the initiator via a data frame the time it received multiple UWB segment signals #1 and the time it transmitted multiple UWB segment signals #2. The initiator then calculates the Time of Flight (TOF) for the responder based on the time it transmitted multiple UWB segment signals #1, the time it received multiple UWB segment signals #2, the time the responder received multiple UWB segment signals #1, and the time the responder transmitted multiple UWB segment signals #2, thereby completing the distance measurement for the responder.

[0146] However, in the above process where the initiator performs one-to-one distance measurement to responders using UWB segment signals, the initiator must complete the distance measurement to the responder within a few milliseconds, resulting in low distance measurement efficiency. If the initiator performs one-to-many distance measurement to multiple responders, and the initiator still schedules all responders one by one in the above manner, the process of scheduling multiple responders is complex, resulting in long distance measurement times and low distance measurement efficiency.

[0147] In embodiments of this application, the first initiating device is one of a plurality of second initiating devices. Each of the plurality of second initiating devices is a device that initiates a ranging round, and each second initiating device may initiate a ranging request to another device by transmitting a polling frame. The first responding device is one of a plurality of second responding devices. Each of the plurality of second responding devices may receive a polling frame transmitted by the first initiating device. If a second responding device decides to participate in the ranging round of the first initiating device, the second responding device may reply to the first initiating device in a response frame to determine whether the second responding device should participate in the ranging round of the first initiating device.

[0148] 2. Signal transmission method 100

[0149] One embodiment of this application provides a signal transmission method 100. Figure 5 is a schematic interaction flowchart of the signal transmission method 100. The signal transmission method 100 is described in terms of interaction between a first initiating device and a first responding device. The signal transmission method 100 includes, but is not limited to, the following steps.

[0150] S101: The first initiating device transmits a polling frame which includes time-frequency position information of N first ultra-wideband (UWB) segment signals and first delay information for each of M second responding devices to reply to the first initiating device in a response frame.

[0151] N and M are integers greater than or equal to 2. The N first UWB segment signals are N portions of the UWB signal used for ranging by the first initiating device; that is, the first initiating device divides the UWB signal used for ranging into N first UWB segment signals. This technique can increase the transient power of the transmitted signal, increase the signal coverage, and increase the signal-to-noise ratio of the signal received at the receiving end.

[0152] Each of the N first UWB segment signals has a time length of less than 1 ms, and the time interval between any two first UWB segment signals is 1 ms or greater. The time length of each first UWB segment signal and the time interval between two first UWB segment signals are not limited to the embodiments of this application. In this embodiment of this application, an example is used for illustrative purposes in which the time interval between any two first UWB segment signals is 1 ms. For example, the time-frequency position information for each of the N first ultrawideband UWB segment signals is shown in Figure 6, where the time interval between any two first UWB segment signals is 1 ms.

[0153] Furthermore, the delay in the first delay information is the delay between the first initiating device sending the polling frame, i.e., the delay between the timestamp of the polling frame. Different second responding devices have different first delay information, i.e., the delays for all second responding devices to reply to the first initiating device with a response frame are different. Thus, all second responding devices reply to the first initiating device with a response frame after a different delay from the time the first device sent the polling frame. In other words, the first initiating device constitutes one first delay information for each second responding device to reply to the first initiating device with a response frame, so that all second responding devices can reply to the first initiating device with a response frame at different times and thereby participate in the ranging round of the first initiating device.

[0154] For example, the delay in the first delay information for responding device #1 to reply to the first initiating device in a response frame is 5 μs, the delay in the first delay information for responding device #2 to reply to the first initiating device in a response frame is 8 μs, and the time when the first initiating device sends a polling frame is time #A. If both responding device #1 and responding device #2 decide to participate in the ranging initiated by the first initiating device, responding device #1 will reply to the first initiating device in a response frame at time 5 μs after time #A, and responding device #2 will reply to the first initiating device in a response frame at time 8 μs after time #A. Furthermore, both responding device #1 and responding device #2 will participate in the ranging round of the first initiating device.

[0155] The polling frame timestamp may be carried within the polling frame, or it may be delivered by the first initiating device to M second responding devices by using other signaling. For example, the first initiating device notifies the M second responding devices of the polling frame timestamp based on downlink control information (DCI).

[0156] The polling frame contains the time-frequency position information of N first UWB segment signals to broadcast the time-frequency position information of N first UWB segment signals to M second responding devices, which is used when a first initiating device performs distance measurement. Thus, each of the M second responding devices can subsequently receive N first UWB segment signals based on the time-frequency position information of N first UWB segment signals.

[0157] The polling frame contains a first delay information for each of the M second responding devices to reply to the first initiating device in the response frame, indicating that the first initiating device initiates a ranging request to the M second responding devices. Each of the M second responding devices has one first delay information for replying to the first initiating device in the response frame, indicating that the first initiating device performs narrowband signal scheduling to the M second responding devices in a time-division multiplexer. Thus, all M second responding devices can reply to the first device in response frames at different times in order to participate in the ranging round of the first initiating device. Furthermore, this technique helps to perform ranging on multiple second responding devices as performed by the first initiating device, i.e., it helps to improve ranging efficiency.

[0158] It can be understood that the first initiating device may broadcast polling frames to M second responding devices to reduce signaling overhead.

[0159] In one optional implementation, the polling frame may further include second delay information for each of the M second responding devices to respond to the first UWB segment signal from the first initiating device. The delay in the second delay information is the delay for all N first UWB segment signals. In other words, the first initiating device configures a delay for each second responding device to respond to the N first UWB segment signals from the first initiating device. This technique helps all second responding devices respond to the first UWB segment signal at different times.

[0160] In one implementation of another option, the polling frame further includes identical third delay information for M second responders to respond to a first UWB segment signal from a first starter device, and an orthogonal sequence index for each second responder. The orthogonal sequence of each second responder is used by the second responders to generate an orthogonal UWB segment signal. In other words, the first starter device comprises identical delay information for M second responders to respond to N first UWB segment signals, and different orthogonal sequence indices for all second responders to generate an orthogonal UWB segment signal. Thus, all second responders can simultaneously respond to a first orthogonal UWB signal from a first starter device, and the orthogonal UWB segment signal is determined based on the orthogonal sequence index of the second responders.

[0161] Thus, the first initiating device configures a polling frame such that all M second responding devices simultaneously respond to the first orthogonal UWB segment signal, and therefore the first initiating device also simultaneously receives the first orthogonal UWB segment signal responded to by all second responding devices. It can be seen that the first initiating device does not need to frequently receive orthogonal UWB segment signals from multiple second responding devices within each time interval of the first UWB segment signal, but only needs to receive orthogonal UWB segment signals from multiple second responding devices at fixed times, thereby reducing the power consumption of the first initiating device.

[0162] Specifically, the first starter device is active when it transmits N first UWB segment signals and receives multiple first orthogonal UWB segment signals. The first starter device is idle during the interval between the N first UWB segment signals, other than the time spent transmitting and receiving the multiple first orthogonal UWB segment signals. It can be seen that this technique can significantly reduce the time the first starter device is active and thus reduce its power consumption.

[0163] In one implementation of further alternative options, the polling frame further includes a fourth delay information for each second responding device to send a data frame to the first initiating device. The delay in the fourth delay information is the delay relative to the last time interval of the time intervals of N first UWB segment signals. The data frame includes the time difference between receiving and transmitting the UWB segment signal for each second responding device. Specifically, the first initiating device, through the polling frame, constitutes the reported time difference between receiving and transmitting the UWB segment signal for each second responding device. Different second responding devices have different fourth delay information, and as a result, different second responding devices send data frames to the first initiating device at different times. This technique helps the first initiating device to obtain the time difference between receiving and transmitting the UWB segment signal for multiple second responding devices, and further helps the first initiating device to calculate the TOF for multiple responding devices and perform ranging for multiple responding devices.

[0164] Optionally, the polling frame further includes the addresses of M second responding devices. Thus, after receiving a polling frame, each second responding device determines, based on the address information in the polling frame, whether it can participate in the ranging round of the first initiating device.

[0165] From the above, it can be seen that, in addition to the time-frequency position information of the N first UWB segment signals, the polling frame further includes one or more items from Table 1 below. [Table 1]

[0166] S102: The first responding device receives a polling frame.

[0167] S103: The first responding device sends a response frame to the first initiating device based on the timestamp of the polling frame and first delay information for the first responding device to reply to the first initiating device in the response frame.

[0168] The first responding device is one of M second responding devices. The response frame is used to confirm the time-frequency position information of N first UWB segment signals in the polling frame. If any of the M second responding devices decide to participate in the ranging round of the first initiating device, the second responding device may send a response frame to the first initiating device.

[0169] A polling frame received by any second responding device includes first delay information for the second responding device to reply to the first initiating device in the response frame. Thus, any second responding device can send a response frame to the first initiating device based on the delay in the first delay information for the second responding device and the timestamp of the polling frame. It can be understood that any second responding device determines when it will send a response frame based on the delay in the first delay information for the second responding device and the timestamp of the polling frame, and then sends the response frame to the first initiating device at that time.

[0170] For example, as shown in Figure 6, the second response device #1 determines the transmission time as time #1 based on the first delay information for the second response device #1 and the timestamp of the polling frame, and the second response device #M determines the transmission time as time #M based on the first delay information for the second response device #M and the timestamp of the polling frame. In this case, the second response device #1 sends response frame 1 to the first initiator at time #1, and the second response device #M sends response frame M to the first initiator at time #M.

[0171] Specifically, any of the M second response devices can send a response frame to the first start device based on first delay information for that response device, and different second response devices send response frames to the first start device at different times. In other words, different response devices can participate in the ranging round of the first start device by sending response frames to the first start device at different times. Thus, multiple second response devices can participate in the ranging round of the first start device so that the first start device performs ranging on multiple second response devices.

[0172] S104: The first initiating device receives multiple response frames based on the timestamp of the polling frame and first delay information for each second responding device to reply to the first initiating device in the response frame.

[0173] Accordingly, the first initiating device can determine when each second responding device should send a response frame based on the polling frame's timestamp and first delay information for each second responding device to reply to the first initiating device with a response frame, and as a result, the first initiating device can receive response frames from multiple second responding devices at different times when the response frames are received.

[0174] The first initiating device can determine, based on the received response frame, which of the M second response devices has decided to participate in the ranging round, and thus can subsequently perform ranging using the UWB segment signal returned by the second response device that transmitted the response frame.

[0175] S105: The first initiating device transmits N first UWB segment signals separately based on the time-frequency position information of the N first UWB segment signals.

[0176] The first initiating device transmits N first UWB segment signals, each at a different time-frequency position of the N first UWB segment signals. For example, as shown in Figure 6, the first initiating device transmits N first UWB segment signals, each at a different time-frequency position.

[0177] In one optional implementation, the first initiating device transmitting N first UWB segment signals separately based on the time-frequency position information of N first UWB segment signals includes, when the first timer has not expired and M response frames have been received, the first initiating device transmitting N first UWB segment signals separately based on the time-frequency position information of N first UWB segment signals, or when S response frames have been received and the first timer has expired, the first initiating device transmitting N first UWB segment signals separately based on the time-frequency position information of N first UWB segment signals. The first timer is triggered when a polling frame is transmitted, and S is an integer greater than or equal to 1 and less than M.

[0178] It is understood that the first initiating device starts a first timer when it sends a polling frame. The duration of the first timer is self-defined by the first initiating device. When the first timer has not expired and response frames have been received from all M second responding devices, the first initiating device transmits N first UWB segment signals separately based on the time-frequency position information of N first UWB segment signals. When response frames have been received from some of the M second responding devices and the first timer has expired, the first initiating device transmits N first UWB segment signals separately based on the time-frequency position information of N first UWB segment signals, without continuing to wait for responses from the other second responding devices. This technique avoids ranging failures that would occur if the first initiating device were to indefinitely wait for responses in response frames from the second responding devices.

[0179] Optionally, when the first timer expires, the first initiating device does not receive any response frames returned by any of the second responding devices, i.e., S is equal to 0. Thus, the first initiating device retransmits the polling frame, i.e., rebroadcasts the polling frame to M second responding devices, re-requesting the M second responding devices to participate in the ranging round.

[0180] S106: The first response device receives N first UWB segment signals separately based on the time-frequency position information of the N first UWB segment signals.

[0181] A polling frame received by any second responding device contains time-frequency position information for N first UWB segment signals, and as a result, any second responding device can receive N first UWB segment signals at different time-frequency positions based on the time-frequency position information for N first UWB segment signals.

[0182] S107: The first responding device separately transmits the UWB segment signals to the first initiating device.

[0183] Whenever any responding device receives a first UWB segment signal, any responding frame replies to the first UWB segment signal from the first initiating device, i.e., transmits a UWB segment signal to the first initiating device.

[0184] In one optional implementation, if the polling frame further includes second delay information for each second responding device to respond to a first UWB segment signal from the first initiating device, any second responding device separately sends N second UWB segment signals to the first initiating device based on the second delay information for the second responding device to respond to a first UWB segment signal from the first initiating device.

[0185] In other words, each second responding device can thus determine the time to transmit N second UWB segment signals to the first initiating device based on second delay information for the second responding device, and transmit N second UWB segment signals to the first initiating device separately at the determined time. All second responding devices have different second delay information. Therefore, within each time interval of the first UWB segment signal, all second responding devices transmit the second UWB segment signals to the first initiating device at different times.

[0186] For example, as shown in Figure 6, all second response devices transmit second UWB segment signals to the first start device at different times within each time interval of the first UWB segment signal, and each second response device transmits N second UWB segment signals separately.

[0187] In one implementation of another option, if the polling frame further includes identical third delay information for M second responding devices to reply to a first UWB segment signal from the first initiating device, and the orthogonal sequence index of each second responding device, then any second responding device separately transmits N first orthogonal UWB segment signals to the first initiating device based on the third delay information. The first orthogonal UWB segment signals are determined based on the orthogonal sequence index of the first responding device.

[0188] Specifically, within each time interval of the first UWB segment signal, different second response devices simultaneously transmit the first orthogonal UWB segment signal to the first initiating device; that is, multiple second response devices simultaneously transmit the first orthogonal UWB segment signal, orthogonal in a code-decomposition scheme. The time at which the first orthogonal UWB segment signal is transmitted within each time interval of the first UWB segment signal is determined based on third delay information and the time at which the first UWB segment signal is transmitted within the time interval of the first UWB segment signal.

[0189] The first orthogonal UWB segment signal from each second response device is determined based on the orthogonal sequence index of the second response device. Implementations in which each second response device generates the first orthogonal UWB segment signal based on the orthogonal sequence index are not limited to the embodiments of this application. For example, different first orthogonal UWB segment signals may be realized based on M sequences of different parameters, or on repetitions of M sequences of different parameters. The formula for generating the M sequences is as follows: d(n) = 1 - 2x(m) (1) m=[n+43N ID ] mod L (2)

[0190] Here, 0 ≤ n ≤ L, x(i+7) = [x(i+4) + x(i)] mod 2, where L is the length of the M sequence, and N ID is the orthogonal sequence index assigned within the polling frame, where ZL is the number of pulses in the first orthogonal UWB segment signal, and Z is a positive integer. Furthermore, [x(6) x(5) x(4) x(3) x(2) x(1) x(0)] = [1 1 1 0 1 1 0]. In this case, the first orthogonal UWB segment signal is obtained by encoding an M sequence of length L using binary phase shift keying (BPSK) and performing the encoding Z times.

[0191] For example, as shown in Figure 7, within each time interval of the first UWB segment signal, all second response devices simultaneously transmit different first orthogonal UWB segment signals to the first start device, while each second response device transmits N first orthogonal UWB segment signals separately.

[0192] Thus, within each time interval of the first UWB segment signal, different second response devices simultaneously transmit different first orthogonal UWB segment signals to the first device, and as a result, the first initiating device also simultaneously receives different first orthogonal UWB segment signals from multiple second response devices. The first initiating device is active when it transmits N first UWB segment signals and receives multiple first orthogonal UWB segment signals. The first initiating device is idle during the intervals between the N first UWB segment signals, other than the time spent transmitting and receiving the N first orthogonal UWB segment signals.

[0193] Compared to the aforementioned case where all second response devices transmit the second UWB segment signal at different times, the first initiating device does not need to frequently receive multiple second UWB segment signals. This technique reduces the active time of the first initiating device, thereby reducing its power consumption.

[0194] Furthermore, within each time interval of the first UWB segment signal, the number of turnarounds between the time for the first initiating device to transmit the first UWB signal and the time for the first initiating device to receive the first orthogonal UWB segment signal returned by multiple second responding devices can be set to 1, thereby reducing the risk of occupying turnaround time. In addition, the idle time within each time interval of the first UWB segment signal is increased, and multiple second responding devices can return response frames at different times during the idle time, thereby increasing the number of second responding devices participating in the ranging of the first initiating device and improving ranging efficiency.

[0195] S108: The first initiating device receives multiple UWB segment signals separately.

[0196] Correspondingly, if the polling frame further includes second delay information for each second responding device to reply to the first UWB segment signal from the first initiating device, the first initiating device receives a plurality of second UWB segment signals separately based on the second delay information for each second responding device to reply to the first UWB segment signal from the first initiating device.

[0197] Optionally, if the polling frame further includes identical third delay information for responding to first UWB segment signals from the first initiating device, and the orthogonal sequence index of each second initiating device, the first initiating device receives multiple first orthogonal UWB segment signals separately based on the third delay information and the orthogonal sequence index of each second initiating device.

[0198] It can be understood that an implementation in which the first initiating device receives multiple UWB segment signals separately is similar to an implementation in which each second responding device transmits a UWB segment signal separately. For details, please refer to the above implementation in which each second responding device transmits a UWB segment signal separately. We will not go into detail again.

[0199] In one optional implementation, the polling frame may further include a fourth delay information for each second responding device to transmit a data frame to the first initiating device. Thus, the first responding device can transmit a data frame to the first initiating device based on the fourth delay information for the first responding device to transmit a data frame to the first initiating device, the data frame including the time for the first responding device to receive N first UWB segment signals and the time for transmitting N second UWB segment signals or N first orthogonal UWB segment signals.

[0200] Specifically, any second responding device may further determine, based on fourth delay information for the second responding device, the time to send a data frame to the first initiating device, and as a result, the second responding device sends the data frame to the first initiating device at the determined time and reports to the first initiating device the time difference between receiving and transmitting the UWB segment signal for the second responding device. The first initiating device also performs distance measurement based on the time difference between receiving and transmitting the UWB segment signal.

[0201] Accordingly, the first initiating device can receive a plurality of data frames based on a fourth delay information for each second responding device to transmit a data frame to the first initiating device, obtain from the plurality of data frames the time difference between receiving and transmitting UWB segment signals for the plurality of second responding devices, and further perform ranging for the plurality of second responding devices.

[0202] For example, as shown in Figures 6 and 7, different second response devices send data frames to the first start device at different times determined based on the fourth delay information, and the M second response devices send a total of M data frames to the first start device. The first start device receives these multiple data frames at different times.

[0203] In this embodiment of the application, the time for each second responder device to transmit a UWB segment signal and the time for the first initiator device to transmit a first UWB segment signal must be turned around, i.e., the time for each second responder device to transmit a UWB segment signal is alternated with the time for the first initiator device to transmit a first UWB segment signal. For example, in Figures 6 and 7, there is a turnaround time after the first initiator device has finished transmitting the first UWB segment signal and before the first initiator device begins transmitting the first UWB segment signal. Thus, the first device can distinguish between the time for transmitting the first UWB segment signal and the time for receiving UWB segment signals from multiple second responder devices, thereby facilitating distance measurement based on these two times.

[0204] It can be understood that this embodiment of the application further includes a procedure for performing distance measurement on multiple response devices using multiple start devices, which is derived from the procedure for performing distance measurement on multiple response devices using one start device as shown in Figures 6 and 7.

[0205] It is understood that, in this embodiment of the application, a polling frame transmitted by a first initiating device includes first delay information for each of a plurality of second responding devices to reply to the first initiating device in a response frame, i.e., includes time-division scheduling for the plurality of second responding devices. Thus, response frames from the plurality of second responding devices can be received at different times, and therefore, the plurality of second responding devices participate in the ranging or sensing process initiated by the first initiating device. Furthermore, the first initiating device initiates a ranging round by transmitting N first UWB segment signals. The plurality of second responding devices participate in the ranging round of the first initiating device by replying to the first initiating device in UWB segment signals. This technique helps the first initiating device to perform ranging for the plurality of second responders in a short time, and helps improve ranging efficiency.

[0206] 3. Signal transmission method 200

[0207] One embodiment of this application further provides a signal transmission method 200. Figure 8 is a schematic interaction flowchart of the signal transmission method 200. The signal transmission method 200 is described in terms of interaction between a first initiating device and a first responding device. The signal transmission method 200 includes, but is not limited to, the following steps:

[0208] S201: A first initiating device transmits a polling frame which includes time-frequency position information of N first ultra-wideband (UWB) segment signals, the same response time for M second responding devices to reply to the first initiating device in response frames, and a set of subcarriers for all M second responding devices to reply to the first initiating device in response frames, wherein the narrowband signals transmitted during the response time include multiple subcarriers.

[0209] N and M are integers greater than or equal to 2.

[0210] For information on the N first ultra-wideband (UWB) segment signals and the time-frequency position information of the N first ultra-wideband (UWB) segment signals, please refer to the explanation in S101. Further details will not be provided here.

[0211] In other words, the first initiating device, through polling frames, constitutes the same response time for M second responding devices to reply to the first initiating device with response frames, and a set of subcarriers for all second responding devices to reply to the first initiating device with response frames. Specifically, the first initiating device performs narrowband scheduling for the M second responding devices in a frequency division scheme so that the M second responding devices can reply to the first initiating device using response frames on different subcarrier sets in the same response time. Thus, the M second responding devices can participate in the ranging round of the first initiating device in a frequency division scheme, thereby helping the first initiating device perform sensing or measurement on multiple second responding devices and improving ranging efficiency.

[0212] For other implementations of the polling frame in this embodiment of this application, please refer to the description in S101. Further details will not be provided here.

[0213] Referring to the implementation of polling frames in S101, it can be seen that polling frames may contain the information in Table 2. [Table 2]

[0214] S202: The first responding device receives a polling frame.

[0215] S203: The first responding device transmits a response signal based on the response time and the set of subcarriers for the first responding device to reply to the first initiating device in the response frame.

[0216] Since the polling frame includes the response times of M second response devices and the subcarrier sets for all second response devices, any second response device can send a response signal to the first start device on the subcarrier set for the first response device during the response time when it decides to participate in the ranging of the first start device. For example, as shown in Figure 9, multiple second response devices send response signals to the first start device on different subcarrier sets at time #a, and multiple response signals form a response frame.

[0217] S204: The first initiating device receives a response frame based on the response time and a set of subcarriers for all second responding devices to reply to the first initiating device in a response frame, the response frame comprising a plurality of response signals.

[0218] Correspondingly, the first initiating device receives a response frame at the above response time, the response frame containing response signals on different subcarrier sets, the response signals on different subcarrier sets originating from a different second response device.

[0219] In this embodiment of the application, the first initiating device receives response signals from multiple second response devices at the same response time. Compared to S104, in which the first initiating device receives response frames from different second response devices at different times, in this implementation, when receiving response frames, the first initiating device is active only at the above response time, and as a result, the active time of the first initiating device can be reduced, thereby reducing the power consumption of the first initiating device.

[0220] S205: The first initiating device transmits N first UWB segment signals separately based on the time-frequency position information of the N first UWB segment signals.

[0221] S206: A first response device receives N first UWB segment signals separately based on the time-frequency position information of the N first UWB segment signals.

[0222] For the implementation of S205 and S206, please refer to the implementations of S105 and S106 described above. Further details will not be explained again.

[0223] S207: The first responding device separately transmits the UWB segment signals to the first initiating device.

[0224] A UWB signal transmitted to the first initiating device by an arbitrary second responding device is a reply signal to the first UWB segment signal transmitted by the first initiating device.

[0225] In one optional implementation, if the polling frame further includes second delay information for each second responding device to respond to the first UWB segment signal from the first initiating device, the first responding device separately transmits N second UWB segment signals to the first initiating device based on the second delay information for the first responding device to respond to the first UWB segment signal from the first initiating device. For a specific implementation of this, see the explanation in S107.

[0226] For example, as shown in Figure 9, after receiving the first UWB segment signal from the first initiating device within each time interval of the first UWB segment signal, all second responding devices transmit a second UWB segment signal to the first initiating device at different times based on their respective second delay information. Each second responding device transmits a total of N second UWB segment signals separately.

[0227] In one implementation of another option, if the polling frame further includes identical third delay information for M second responding devices to respond to a first UWB segment signal from the first initiating device, and the orthogonal sequence index of each second responding device, the first responding device transmits the first orthogonal UWB segment signal to the first initiating device based on the third delay information and the orthogonal sequence index of the first responding device. For a specific implementation of this, see the explanation in S107.

[0228] For example, as shown in Figure 10, after receiving the first UWB segment signal within each time interval of the first UWB segment signal, all second response devices transmit the first orthogonal UWB segment signal, determined based on the orthogonal sequence index of each second response device, at the same time determined based on the third delay information. Within the time intervals of N first UWB segment signals, each response device transmits a total of N first orthogonal UWB segment signals to the first start device.

[0229] Furthermore, within each time interval of the first UWB segment signal, the number of turnarounds between the time it takes for the first initiating device to transmit the first UWB signal and the time it takes for the first initiating device to receive the first orthogonal UWB segment signal returned by multiple second responding devices can be set to 1, thereby reducing the risk of occupying turnaround time. This enhances the robustness of the system. In addition, the idle time within each time interval of the first UWB segment signal increases, and multiple second responding devices can return response frames at different times during the idle time. As a result, the number of second responding devices participating in the ranging of the first initiating device can be increased, which improves ranging efficiency.

[0230] S208: The first initiating device receives multiple UWB segment signals separately.

[0231] In one optional implementation, if the polling frame further includes second delay information for each second responding device to respond to the first UWB segment signal from the first initiating device, the first initiating device receives a plurality of second UWB segment signals based on the second delay information for each second responding device to respond to the first UWB segment signal from the first initiating device.

[0232] In one implementation of another option, if the polling frame further includes identical third delay information for responding to first UWB segment signals from the first initiating device and the orthogonal sequence index of each second initiating device, the first initiating device receives a plurality of first orthogonal UWB segment signals based on the third delay information and the orthogonal sequence index of each second initiating device.

[0233] For a detailed implementation of how the first initiating device receives multiple UWB segment signals separately, please refer to the explanation in S108. Further details will not be provided here.

[0234] In one implementation of further alternative options, the polling frame further includes the same data frame time for all second responding devices to transmit a data frame to the first initiating device, and a set of subcarriers for all second responding devices to transmit a data frame to the first initiating device. Thus, the first responding device can further transmit a data signal based on the above data frame time and the set of subcarriers for the first responding device to transmit a data frame to the first initiating device. The data signal includes a time difference between the first responding device receiving N first UWB segment signals and the first responding device transmitting N second UWB segment signals or the first responding device transmitting N first orthogonal UWB segment signals.

[0235] Correspondingly, the first initiating device can receive data frames on different subcarrier sets during the data frame time, and the data frames include data signals from multiple second responding devices. Thus, the first initiating device does not need to receive data frames from different second responding devices at different times, but only needs to receive data frames during a single data frame time, thereby reducing the power consumption of the first initiating device.

[0236] It can be understood that this embodiment of the application further includes a procedure for performing ranging on multiple response devices by multiple start devices, which is derived from the procedure for performing ranging on multiple response devices by one start device in Figures 9 and 10. It can be understood that, in this embodiment of the application, the first start device constitutes, through a polling frame, the same response time for which M second response devices reply in response frames, and a set of subcarriers for which all second response devices reply in response frames, i.e., constitutes frequency division scheduling for the M second response devices. Thus, the M second response devices transmit response signals to the first start device on different subcarrier sets at the same response time. As a result, some or all of the M second response devices can participate in the ranging round of the first start device, thereby improving ranging efficiency.

[0237] Signal transmission method 300

[0238] One embodiment of this application further provides a signal transmission method 300. Figure 11 is a schematic interaction flowchart of the signal transmission method 300. The signal transmission method 300 is described in terms of the interaction between a control device, a first initiating device, and a first responding device. The signal transmission method 300 includes, but is not limited to, the following steps:

[0239] S301: The control device transmits a polling frame which includes time-frequency position information for N ultra-wideband (UWB) segment signal groups, first delay information for each of M second response devices to reply to the control device in a response frame, and fifth delay information for each of X second initiating devices to reply to the control device in a response frame.

[0240] N, M, and X are integers greater than or equal to 2. The control device may be an independent device or any one of X second start devices. The UWB segment signal group includes multiple second orthogonal UWB segment signals. The delay in the first delay information and the delay in the fifth delay information are both delays relative to the polling frame's timestamp.

[0241] In other words, the control device configures delay information via polling frames for each of the M second response devices and each of the X second start devices to send response frames to the first start device in order to perform time-division scheduling for the M second response devices and X second start devices. Thus, multiple devices from the M second response devices and multiple devices from the X second start devices can participate in the same ranging round, thereby helping to improve ranging efficiency.

[0242] In one optional implementation, the polling frame further includes the orthogonal sequence index of each second initiating device, the orthogonal sequence index of each of the M second responding devices, and identical third delay information for all second responding devices to respond to the second orthogonal UWB segment signals from the first initiating device. Thus, any second initiating device can separately transmit N second orthogonal UWB segment signals based on the time-frequency position information of N UWB segment signal groups and the orthogonal sequence index of the second initiating device. Consequently, any second responding device can receive multiple second orthogonal UWB segment signals based on the time-frequency position information of N UWB segment signal groups and the orthogonal sequence index of each second initiating device.

[0243] Furthermore, any second response device can transmit N third orthogonal UWB segment signals based on the third delay information and the orthogonal sequence index of the second response device. Thus, any second initiating device can receive multiple third orthogonal UWB segment signals based on the third delay information and the orthogonal sequence index of each second response device.

[0244] In one implementation of another option, the polling frame further includes a fourth delay information for each second responding device to transmit a data frame to the second initiating device, so that any second responding device can transmit a data frame based on the fourth delay information for the second responding device. The data frame includes the time when the second responding device receives a second orthogonal UWB segment signal and the time when the second responding device transmits a third orthogonal UWB segment signal. Correspondingly, any first initiating device participating in the ranging round can receive multiple data frames based on the fourth delay information for each second responding device, and further perform ranging on multiple second responding devices based on the time information carried in those data frames.

[0245] Optionally, the polling frame may further include the addresses of M second responding devices and X second initiating devices to request that the devices containing address information participate in the same ranging round.

[0246] S302: The first initiating device receives a polling frame.

[0247] S303: The first responding device receives a polling frame.

[0248] The order in which S302 and S303 are performed is not limited to the embodiments of this application. S302 may be performed after S303, or S303 may be performed after S302.

[0249] Any one of the X second start devices may receive a polling frame. Any one of the M second responder devices may receive a polling frame.

[0250] S304: The first initiating device sends a response frame to the control device based on the timestamp of the polling frame and fifth delay information for the first initiating device to reply to the control device in the response frame.

[0251] Any second initiating device sends a response frame to the control device at a time determined based on the polling frame's timestamp and a fifth delay information for that second initiating device. Different second initiating devices send response frames to the control device at different times based on different fifth delay information.

[0252] For example, as shown in Figure 12, the response frame transmitted by the second initiating device 1 is response frame i1, the response frame transmitted by the second initiating device X is response frame ix, and X second initiating devices transmit response frames at different times.

[0253] S305: The first response device sends a response frame to the control device based on the timestamp of the polling frame and first delay information for the first response device to send a response frame back to the control device.

[0254] Any second response device sends a response frame to the control device at a time determined based on the polling frame's timestamp and first delay information for that second response device. Different second response devices send response frames to the control device at different times based on different first delay information.

[0255] For example, as shown in Figure 12, the response frame transmitted by the second response device 1 is response frame r1, the response frame transmitted by the second response device M is rm, and M second response devices transmit response frames at different times.

[0256] The order in which S304 and S305 are carried out is not limited to the embodiments of this application. S304 may be carried out after S305, or S305 may be carried out after S304.

[0257] S306: The control device receives multiple response frames based on multiple first delay information, multiple fifth delay information, and the timestamp of the polling frame.

[0258] Correspondingly, the control device can determine the time at which multiple second initiating devices transmit response frames based on multiple fifth delay information and the timestamps of the polling frames, and as a result, the control device can receive response frames from different second initiating devices at different determined times. The control device can further determine the time at which multiple second responding devices transmit response frames based on multiple first delay information and the timestamps of the polling frames, and as a result, the control device can receive response frames from different second responding devices at different determined times.

[0259] S307: The first initiating device transmits N second orthogonal UWB segment signals separately.

[0260] In one optional implementation, the polling frame further includes the orthogonal sequence index of each second initiating device. Thus, any second initiating device can transmit N second orthogonal UWB segment signals based on the time-frequency position information of N UWB segment signal groups and the orthogonal sequence index of the second initiating device. Specifically, each second initiating device that replies in the response frame can transmit a second orthogonal UWB segment signal, determined based on the orthogonal sequence of the second initiating device, at N transmission times determined based on the time-frequency position information of the N UWB segment signal groups.

[0261] Therefore, within each time interval of the UWB segment signal group, multiple second initiating devices simultaneously transmit different second orthogonal UWB segment signals, each second orthogonal UWB segment signal being an orthogonal UWB segment signal determined by the corresponding second initiating device based on the orthogonal sequence index of the corresponding second initiating device. By having multiple second initiating devices transmit the second orthogonal UWB segment signals at once within each time interval of the UWB segment signal group, the risk of any second initiating device occupying the receive-to-transmit turnaround time is reduced.

[0262] For example, as shown in Figure 12, any one of the X second initiating devices transmits N second orthogonal UWB segment signals separately at N times determined based on the time-frequency position information of N UWB segment signal groups. The second orthogonal UWB segment signals transmitted by multiple second initiating devices are included at the position of each UWB segment signal group.

[0263] S308: The first response device receives multiple second orthogonal UWB segment signals separately.

[0264] Correspondingly, any second responding device separately receives multiple second orthogonal UWB segment signals at N time intervals determined based on the time-frequency position information of N UWB segment signal groups, based on the orthogonal sequence index of each second initiating device.

[0265] S309: The first response device transmits multiple third orthogonal UWB segment signals separately.

[0266] In one optional implementation, the polling frame further includes the orthogonal sequence index of each second initiating device, the orthogonal sequence index of each of the M second responding devices, and identical third delay information for all second responding devices to respond to the second orthogonal UWB segment signal from the first initiating device. Thus, any second responding device can transmit a third orthogonal UWB segment signal, determined based on the orthogonal sequence index of the second responding device, at N times determined based on the third delay information. All second responding devices reply to the first initiating device with different third orthogonal UWB segment signals at the same time determined based on the third delay information.

[0267] For example, as shown in Figure 12, all of the different second response devices simultaneously respond with a third orthogonal UWB segment signal.

[0268] Thus, each second response device can be active during the time it receives the second orthogonal UWB segment signal and transmits the third orthogonal UWB segment signal, and idle at other times, thereby reducing the active time of each second response device and lowering the power consumption of each second response device.

[0269] S310: The first initiating device receives multiple third orthogonal UWB segment signals separately.

[0270] Correspondingly, any second initiating device receives different third orthogonal UWB segment signals from multiple second responding devices at the same time determined based on third delay information within each time interval of the UWB segment signal group.

[0271] In one optional implementation, the polling frame further includes fourth delay information for each second responding device to transmit a data frame to the second initiating device. Thus, any second responding device can transmit a data frame based on the fourth delay information for that second responding device. The data frame includes the time at which the second responding device receives a plurality of second orthogonal UWB segment signals and the time at which the second responding device transmits a plurality of third orthogonal UWB segment signals. In other words, different second responding devices transmit different data frames at different times determined based on different fourth delay information.

[0272] Correspondingly, any second initiating device can receive multiple data frames at different times determined based on multiple fourth delay information, and multiple second responding devices can obtain the time at which they received multiple second orthogonal UWB segment signals and the time at which they transmitted multiple third orthogonal UWB segment signals, and furthermore, distance measurement can be performed based on the obtained times.

[0273] For example, as shown in Figure 12, M second response devices transmit data frames separately at different times determined based on different fourth delay information. The data frames transmitted by the M second response devices are data frame 1 through data frame M, respectively.

[0274] In this embodiment of the application, the control device transmits a polling frame through which each of X second initiating devices replies to the control device with a response frame and each of M second responding devices replies to the control device with a response frame, so that some or all of the X second initiating devices may reply to the control device with a response frame at different times, and some or all of the M second responding devices may reply to the control device with a response frame at different times. Thus, multiple second initiating devices and multiple second responding devices that reply with a response frame participate in the same ranging round, thereby helping to perform ranging performed by multiple second initiating devices on multiple second responding devices, i.e., helping to improve ranging efficiency.

[0275] 5. Signal transmission method 400

[0276] One embodiment of this application further provides a signal transmission method 400. Figures 13A and 13B are schematic interaction flowcharts of the signal transmission method 400. The signal transmission method 400 is also described in terms of interaction between a control device, a first initiating device, and a first responding device. The signal transmission method 400 includes, but is not limited to, the following steps:

[0277] S401: The control device transmits a polling frame which includes time-frequency position information for N ultra-wideband (UWB) segment signal groups, a first response time for X second initiating devices to reply to the control device in a response frame, a subcarrier set for all X second initiating devices to reply to the control device in a response frame, a second response time for M second responding devices to reply to the control device in a response frame, and a subcarrier set for all M second responding devices to reply to the control device in a response frame.

[0278] N, M, and X are integers greater than or equal to 2. The control device may be an independent device or any one of the X second start devices. The UWB segment signal group includes a plurality of second orthogonal UWB segment signals.

[0279] The polling frame includes a first response time for the X second start devices to reply to the control device with a response frame and a subcarrier set for all of the X second start devices to reply to the control device with a response frame. As a result, all of the X second start devices can reply to the control device with a first response signal on different subcarrier sets at the first response time. The polling frame includes a second response time for the M second response devices to reply to the control device with a response frame and a subcarrier set for all of the M second response devices to reply to the control device with a response frame. As a result, all of the M second response devices can reply to the control device with a second response signal on different subcarrier sets at the second response time. Specifically, the control device can perform frequency division scheduling for the M second response devices and frequency division scheduling for the X second start devices. Thus, a plurality of devices among the M second response devices and a plurality of devices among the X second start devices can participate in the same ranging round, thereby helping to improve the ranging efficiency.

[0280] Also, all of the M second response devices simultaneously reply to the control device with a second response signal, and all of the X second start devices also simultaneously reply to the control device with a first response signal, and the control device simultaneously receives the first response frame and the second response frame. This can reduce the active time of the control device, that is, can reduce the power consumption of the control device. Also, in this way, multiple groups of second response devices and multiple groups of second start devices can participate in the same ranging round, thereby implementing ranging performed by more second start devices on more second response devices, and further improving the ranging efficiency.

[0281] For other implementations of the polling frame, refer to the description in S301. Details will not be described again.

[0282] S402: The first start device receives the polling frame.

[0283] S403: The first response device receives the polling frame.

[0284] The execution order of S402 and S403 is not limited in the embodiments of this application. S402 may be executed after S403, or S403 may be executed after S402.

[0285] S404: The first start device transmits a first response signal to the control device based on the first response time and the subcarrier set for the first start device to reply to the control device with a response frame.

[0286] Any second start device can reply to the control device with a first response signal on the subcarrier set for the second start device at the first response time. Different second start devices transmit different first response signals to the control device on different subcarrier sets at the first response time.

[0287] For example, as shown in Figure 14, multiple second initiating devices transmit different first response signals at a first response time, forming a first response frame (response frame i) with the multiple first response signals, and multiple second response devices transmit different second response signals at a second response time, forming a second response frame (response frame r) with the multiple second response signals.

[0288] S405: The first response device transmits a second response signal to the control device based on the second response time and the set of subcarriers for which the first response device sends a response frame back to the control device.

[0289] The order in which S404 and S405 are carried out is not limited to the embodiments of this application. S404 may be carried out after S405, or S405 may be carried out after S404.

[0290] S406: The control device receives a first response frame based on a first response time and a set of subcarriers for all second initiating devices to reply to the control device in response frames, the first response frame comprising a plurality of first response signals.

[0291] S407: The control device receives a second response frame based on a second response time and a set of subcarriers for all second response devices to reply to the control device in response frames, the second response frame comprising a plurality of second response signals.

[0292] The order in which S406 and S407 are carried out is not limited to the embodiments of this application. S406 may be carried out after S407, or S407 may be carried out after S406.

[0293] S408: The first start device transmits N second orthogonal UWB segment signals separately.

[0294] S409: The first response device receives multiple second orthogonal UWB segment signals separately.

[0295] S410: The first response device transmits multiple third orthogonal UWB segment signals separately.

[0296] S411: The first initiating device receives multiple third orthogonal UWB segment signals separately.

[0297] For the implementation of S408 to S411, please refer to the implementation described above in S307 to S310. Further details will not be explained again.

[0298] In one implementation of another option, the polling frame further includes a data frame time during which M second responding devices transmit data frames to a second starter device, and a set of subcarriers for all M second responding devices to transmit data frames to the second starter device. Thus, different second responding devices can transmit data signals to the second starter device on different subcarrier sets during the same data frame time, and multiple data signals can form a data frame.

[0299] Correspondingly, any second initiating device can receive a data frame during the data frame time, the data frame containing multiple data signals, all of which are carried on different subcarrier sets. Each data signal includes a time difference between receiving and transmitting the UWB segment signal for the first responding device, and as a result, any second initiating device can perform distance measurement based on the time carried by each data signal.

[0300] It is understood that, in this embodiment of the present application, the control device transmits a polling frame, through which it configures, for X second initiators, a first response time for the X second initiators to reply to the control device with response frames, and a subcarrier set for all X second initiators to reply to the control device with response frames; and through which it configures, for M second responders, a second response time for the M second responders to reply to the control device with response frames, and a subcarrier set for all M second responders to reply to the control device with response frames, so that a plurality of the X second initiators can reply to the control device with a first response signal at the first response time, and a plurality of the M second responders can reply to the control device with a second response signal at the second response time. Thus, a plurality of second initiators replying with response frames and a plurality of second responders replying with response frames participate in the same ranging round. Furthermore, multiple second initiating devices can perform distance measurements on multiple second response devices, thereby improving distance measurement efficiency.

[0301] It can be understood that this embodiment of the application further includes a procedure for performing bidirectional distance measurement on multiple response devices using multiple starting devices, which is obtained based on the procedure for performing one-sided distance measurement on multiple response devices using multiple starting devices as shown in Figures 12 and 14.

[0302] It can be understood that in the above signal transmission method 100, all the second response devices may further transmit data signals to the first starting device on different sub-carrier sets simultaneously, and each data signal includes the time when the second response device receives the first UWB segment signal and the time when the second response device transmits the second UWB segment signal or the first orthogonal UWB segment signal. In other words, the implementation in which each second response device transmits a data frame to the first starting device in the signal transmission method 100 is not limited in the embodiments of this application.

[0303] Similarly, in the above signal transmission method 200, all the second response devices may further transmit data frames to the first starting device at different times. In other words, the implementation in which each second response device transmits a data frame to the first starting device in the signal transmission method 200 is not limited in the embodiments of this application.

[0304] Similarly, the implementation in which each second response device transmits a data frame to the first starting device in the signal transmission method 300 and the signal transmission method 400 is not limited in the embodiments of this application.

[0305] It can be understood that in the signal transmission method 400 described above, all second response devices and all second initiating devices can simultaneously respond to the control device with response signals on different subcarrier sets, forming a response frame with multiple response signals. Optionally, some of the X second initiating devices and some of the M second response devices simultaneously respond to the control device with response signals on different subcarrier sets, while the other devices of the X second initiating devices and the other devices of the M second response devices respond to the control device with response signals on different subcarrier sets at a different time. In other words, the frequency division scheduling scheme of the control device for the X second initiating devices and M second response devices in the signal transmission method 400 is not limited to the embodiments of this application. This would therefore help support more second initiating devices and second response devices participating in the same ranging round.

[0306] 6. Apparatus Embodiments

[0307] To implement all the functions in the methods provided in embodiments of this application, the control device, the first initiating device, or the first responding device may include a hardware structure and / or software module to implement the above functions in the form of a hardware structure, a software module, or a combination of a hardware structure and a software module. Whether the functions among the above functions are implemented by a hardware structure, a software module, or a combination of a hardware structure and a software module depends on the specific application and design constraints of the technical solution.

[0308] As shown in Figure 15, one embodiment of this application provides a communication device 1500. The communication device 1500 may be a component of a first initiating device (e.g., an integrated circuit or chip), or a component of a first responding device (e.g., an integrated circuit or chip), or a component of a control device (e.g., an integrated circuit or chip). Alternatively, the communication device 1500 may be another communication unit configured to carry out the method in the method embodiment of this application. The communication device 1500 may include a communication unit 1501 and a processing unit 1502. Optionally, the communication device 1500 may include a storage unit 1503.

[0309] In one possible design, one or more units of Figure 15 may be implemented by one or more processors, by one or more processors and memory, by one or more processors and transceivers, or by one or more processors, memory, and transceivers. This is not limited to the embodiments of this application. The processors, memory, and transceivers may be arranged separately or integrated.

[0310] The communication device 1500 has the capability to implement a first initiation device as described in embodiments of this application. Optionally, the communication device 1500 has the capability to implement a first response device as described in embodiments of this application. Optionally, the communication device 1500 has the capability to implement a control device as described in embodiments of this application. For example, the communication device 1500 includes corresponding modules, units, or means for the first initiation device to perform steps related to the first initiation device as described in embodiments of this application. Such functions, units, or means may be implemented by software or hardware, by hardware running corresponding software, or by a combination of software and hardware. For further details, see the corresponding descriptions in the corresponding method embodiments described above.

[0311] In one possible design, the communication device 1500 may include a processing unit 1502 and a communication unit 1501. The processing unit 1502 is configured to control the communication unit 1501 to perform data / signaling reception and transmission.

[0312] In one implementation, the communication unit 1501 is configured to transmit a polling frame. The polling frame includes time-frequency position information for N first ultra-wideband (UWB) segment signals and first delay information for each of M second responding devices to reply to the first initiating device in a response frame, where N and M are integers of 2 or greater. The communication unit 1501 is further configured to receive a plurality of response frames based on the timestamp of the polling frame and the first delay information for each second responding device to reply to the first initiating device in a response frame.

[0313] In one optional implementation, the polling frame further includes second delay information for each second responding device to respond to the first UWB segment signal from the first initiating device. The communication unit 1501 is further configured to transmit N first UWB segment signals separately based on the time-frequency position information of N first UWB segment signals and to receive a plurality of second UWB segment signals separately based on the second delay information for each second responding device to respond to the first UWB segment signal from the first initiating device.

[0314] In one optional implementation, the polling frame further includes identical third delay information for M second responding devices to respond to the first UWB segment signal from the first initiating device, and the orthogonal sequence index of each second responding device. The communication unit 1501 is further configured to transmit N first UWB segment signals separately by the first initiating device based on the time-frequency position information of N first UWB segment signals, and to receive a plurality of first orthogonal UWB segment signals separately based on the third delay information and the orthogonal sequence index of each second responding device.

[0315] In one optional implementation, the communication device 1500 is active when it transmits N first UWB segment signals and receives multiple first orthogonal UWB segment signals. The communication device 1500 is idle during the interval time between the N first UWB segment signals, other than the time required to transmit the N first UWB segment signals and the time required to receive the multiple first orthogonal UWB segment signals.

[0316] In one optional implementation, the polling frame further includes a fourth delay information for each second responding device to transmit a data frame to the first initiating device. The communication unit 1501 is further configured to receive a plurality of data frames based on the fourth delay information for each second responding device to transmit a data frame to the first initiating device, each of the plurality of data frames including a time difference between the first responding device receiving N first UWB segment signals and the first responding device transmitting N second UWB segment signals or the first responding device transmitting N first orthogonal UWB segment signals, wherein the first responding device is any one of M second responding devices.

[0317] In one optional implementation, the communication unit 1501 transmits N first UWB segment signals separately based on the time-frequency position information of N first UWB segment signals, specifically, when the first timer has not expired and M response frames have been received, it transmits N first UWB segment signals separately based on the time-frequency position information of N first UWB segment signals, or when S response frames have been received and the first timer has expired, the first timer is triggered when a polling frame is transmitted, and S is an integer greater than or equal to 1 and less than M.

[0318] This embodiment of this application and the method embodiment described above are based on the same concept and produce the same technical effects. For specific principles, please refer to the description of the embodiment described above. Details will not be explained again.

[0319] In another possible design, the communication device 1500 includes a processing unit 1502 and a communication unit 1501. The processing unit 1502 is configured to control the communication unit 1501 to perform data / signaling reception and transmission. The communication unit 1501 is configured to receive a polling frame. The polling frame includes time-frequency position information of N first ultra-wideband (UWB) segment signals and first delay information for each of M second responding devices to reply to the first initiating device in a response frame, where N and M are integers greater than or equal to 2, and the first responding device is any one of the M second responding devices. The communication unit 1501 is further configured to transmit a response frame to the first initiating device based on the timestamp of the polling frame and the first delay information for the first responding device to reply to the first initiating device in a response frame.

[0320] In one optional implementation, the polling frame further includes second delay information for each second responding device to respond to the first UWB segment signal from the first initiating device. The communication unit 1501 is further configured to separately receive N first UWB segment signals based on the time-frequency position information of N first UWB segment signals and to separately transmit N second UWB segment signals to the first initiating device based on the second delay information for the first responding device to respond to the first UWB segment signal from the first initiating device.

[0321] In one implementation of another option, the polling frame further includes identical third delay information for M second responding devices to respond to the first UWB segment signals from the first initiating device, and the orthogonal sequence index of each second responding device. The communication unit 1501 is further configured to receive N first UWB segment signals separately based on time-frequency position information of N first UWB segment signals by the first responding device, and to transmit N first orthogonal UWB segment signals separately to the first initiating device based on the third delay information, the first orthogonal UWB segment signals being determined based on the orthogonal sequence index of the first responding device.

[0322] In one implementation of further other options, the polling frame further includes a fourth delay information for each second responding device to transmit a data frame to the first initiating device. The communication unit 1501 is further configured to transmit a data frame to the first initiating device based on the fourth delay information for the first responding device to transmit a data frame to the first initiating device, the data frame including a time difference between the first responding device receiving N first UWB segment signals and the first responding device transmitting N second UWB segment signals or the first responding device transmitting N first orthogonal UWB segment signals.

[0323] This embodiment of this application and the method embodiment described above are based on the same concept and produce the same technical effects. For specific principles, please refer to the description of the embodiment described above. Details will not be explained again.

[0324] In one further possible design, the communication device 1500 includes a processing unit 1502 and a communication unit 1501. The processing unit 1502 is configured to control the communication unit 1501 to perform data / signaling reception and transmission. The communication unit 1501 is configured to transmit a polling frame. The polling frame includes time-frequency position information of N first ultra-wideband (UWB) segment signals, the same response time for M second responding devices to reply to the first initiating device in a response frame, and a set of subcarriers for all M second responding devices to reply to the first initiating device in a response frame, wherein the narrowband signal transmitted in the response time includes multiple subcarriers, and N and M are integers of 2 or greater. The communication unit 1501 is further configured to receive a response frame based on the response time and the set of subcarriers for all second responding devices to reply to the first initiating device in a response frame, wherein the response frame includes multiple response signals. In one optional implementation, the polling frame further includes second delay information for each second responding device to respond to the first UWB segment signal from the first initiating device. The communication unit 1501 is further configured to transmit N first UWB segment signals separately based on the time-frequency position information of N first UWB segment signals and to receive a plurality of second UWB segment signals separately based on the second delay information for each second responding device to respond to the first UWB segment signal from the first initiating device.

[0325] In one optional implementation, the polling frame further includes identical third delay information for M second responding devices to respond to a first UWB segment signal from a first initiating device, and the orthogonal sequence index of each second responding device. The communication unit 1501 is further configured to transmit N first UWB segment signals separately based on the time-frequency position information of N first UWB segment signals, and to receive a plurality of first orthogonal UWB segment signals separately based on the third delay information and the orthogonal sequence index of each second responding device.

[0326] In one optional implementation, the communication device 1500 is active when it transmits N first UWB segment signals and receives multiple first orthogonal UWB segment signals. The communication device 1500 is idle during the interval time between the N first UWB segment signals, other than the time required to transmit the N first UWB segment signals and the time required to receive the multiple first orthogonal UWB segment signals.

[0327] In one optional implementation, the polling frame further includes the same data frame time for all second responding devices to transmit a data frame to the first initiating device, and a set of subcarriers for all second responding devices to transmit a data frame to the first initiating device. The communication unit 1501 is further configured to receive a data frame based on the above data frame time and the set of subcarriers for all second responding devices to transmit a data frame to the first initiating device, the data frame comprising a plurality of data signals, each of which comprises a time difference between the first responding device receiving N first UWB segment signals and the first responding device transmitting N second UWB segment signals or the first responding device transmitting N first orthogonal UWB segment signals, the first responding device being any one of M second responding devices.

[0328] This embodiment of this application and the method embodiment described above are based on the same concept and produce the same technical effects. For specific principles, please refer to the description of the embodiment described above. Details will not be explained again.

[0329] In one further possible design, the communication device 1500 includes a processing unit 1502 and a communication unit 1501. The processing unit 1502 is configured to control the communication unit 1501 to perform data / signaling reception and transmission. The polling frame includes time-frequency position information of N first ultra-wideband (UWB) segment signals, the same response time for M second responding devices to reply to the first initiating device in response frames, and a set of subcarriers for all of the M second responding devices to reply to the first initiating device in response frames, wherein the narrowband signal transmitted during the response time includes multiple subcarriers, and N and M are integers greater than or equal to 2. The communication unit 1501 is further configured to transmit a response signal to the first initiating device based on the response time and the set of subcarriers for the first responding devices to reply to the first initiating device in response frames, wherein the first responding device is any one of the M second responding devices.

[0330] In one optional implementation, the polling frame further includes second delay information for each second responding device to respond to the first UWB segment signal from the first initiating device. The communication unit 1501 is further configured to receive N first UWB segment signals separately by the first responding device based on the time-frequency position information of the N first UWB segment signals, and to transmit N second UWB segment signals separately to the first initiating device based on the second delay information for the first responding device to respond to the first UWB segment signal from the first initiating device.

[0331] In one optional implementation, the polling frame further includes identical third delay information for M second responding devices to respond to a first UWB segment signal from a first initiating device, and the orthogonal sequence index of each second responding device. The communication unit 1501 is further configured to separately receive N first UWB segment signals based on time-frequency position information of N first UWB segment signals and to separately transmit N first orthogonal UWB segment signals to the first initiating device based on the third delay information, the first orthogonal UWB segment signals being determined based on the orthogonal sequence index of the first responding device.

[0332] In one optional implementation, the polling frame further includes the same data frame time for all second responding devices to transmit a data frame to the first initiating device, and a set of subcarriers for all second responding devices to transmit a data frame to the first initiating device. The communication unit 1501 is further configured to transmit a data signal to the first initiating device based on the data frame time and the set of subcarriers for the first responding devices to transmit a data frame to the first initiating device, the data signal including a time difference between the first responding device receiving N first UWB segment signals and the first responding device transmitting N second UWB segment signals or the first responding device transmitting N first orthogonal UWB segment signals.

[0333] This embodiment of this application and the method embodiment described above are based on the same concept and produce the same technical effects. For specific principles, please refer to the description of the embodiment described above. Details will not be explained again.

[0334] In one further possible design, the communication device 1500 includes a processing unit 1502 and a communication unit 1501. The processing unit 1502 is configured to control the communication unit 1501 to perform data / signaling reception and transmission.

[0335] The communication unit 1501 is configured to transmit a polling frame. The polling frame includes time-frequency position information for N ultra-wideband (UWB) segment signal groups, first delay information for each of M second response devices to reply to the control device in a response frame, and fifth delay information for each of X second initiating devices to reply to the control device in a response frame, where N, M, and X are integers of 2 or more. The communication unit 1501 is further configured to receive a plurality of response frames based on a plurality of first delay information, a plurality of fifth delay information, and a timestamp of the polling frame.

[0336] In one optional implementation, the polling frame further includes the orthogonal sequence index of each second initiating device, the orthogonal sequence index of each of the M second responding devices, and identical third delay information for all second responding devices to reply to the first initiating device with a third orthogonal UWB segment signal.

[0337] In one implementation of another option, the polling frame further includes a fourth delay information for each second responding device to send a data frame to the second initiating device.

[0338] This embodiment of this application and the method embodiment described above are based on the same concept and produce the same technical effects. For specific principles, please refer to the description of the embodiment described above. Details will not be explained again.

[0339] In one further possible design, the communication device 1500 includes a processing unit 1502 and a communication unit 1501. The processing unit 1502 is configured to control the communication unit 1501 to perform data / signaling reception and transmission. The communication unit 1501 is configured to receive a polling frame. The polling frame includes time-frequency position information for N ultra-wideband (UWB) segment signal groups and fifth delay information for each of X second initiating devices to reply to the control device in a response frame, where the first initiating device is any one of the X second initiating devices, and N and X are integers greater than or equal to 2. The communication unit 1501 is further configured to transmit a response frame based on the timestamp of the polling frame and the fifth delay information for the first initiating device to reply to the control device in a response frame.

[0340] In one optional implementation, the polling frame further includes the orthogonal sequence index of each second initiating device, the orthogonal sequence index of each of the M second responding devices, and identical third delay information for all second responding devices to respond to the first UWB segment signal from the first initiating device, where M is an integer greater than or equal to 2. The communication unit 1501 is further configured to transmit N second orthogonal UWB segment signals separately based on the time-frequency position information of N UWB segment signal groups and the orthogonal sequence index of the first initiating device, and to receive a plurality of third orthogonal UWB segment signals separately based on the third delay information and the orthogonal sequence index of each second responding device.

[0341] In one implementation of another option, the polling frame further includes a fourth delay information for each second responding device to transmit a data frame to the second initiating device. The communication unit 1501 is further configured to receive a plurality of data frames based on the fourth delay information for each second responding device to transmit a data frame to the second initiating device, each of which includes a time for the first responding device to receive a plurality of second orthogonal UWB segment signals and a time for the first responding device to transmit a plurality of third orthogonal UWB segment signals, wherein the first responding device is any one of M second responding devices.

[0342] This embodiment of this application and the method embodiment described above are based on the same concept and produce the same technical effects. For specific principles, please refer to the description of the embodiment described above. Details will not be explained again.

[0343] In one further possible design, the communication device 1500 includes a processing unit 1502 and a communication unit 1501. The processing unit 1502 is configured to control the communication unit 1501 to perform data / signaling reception and transmission. The communication unit 1501 is configured to receive polling frames. The polling frames include time-frequency position information for N ultra-wideband (UWB) segment signal groups and first delay information for each of M second responding devices to reply to the control device in a response frame, where the first responding device is any one of the M second responding devices, and N and M are integers greater than or equal to 2. The communication unit 1501 is further configured to transmit a response frame based on the timestamp of the polling frame and the first delay information for the first responding device to reply to the control device in a response frame.

[0344] In one optional implementation, the polling frame further includes the orthogonal sequence index of each of X second initiating devices, the orthogonal sequence index of each second responding device, and identical third delay information for all second responding devices to respond to the first UWB segment signal from the first initiating device, where X is an integer greater than or equal to 2. The communication unit 1501 is further configured to separately receive multiple second orthogonal UWB segment signals based on the time-frequency position information of N UWB segment signal groups and the orthogonal sequence indices of X second initiating devices, and to separately transmit multiple third orthogonal UWB segment signals based on the third delay information and the orthogonal sequence indices of the first responding devices.

[0345] In one optional implementation, the polling frame further includes a fourth delay information for each second responding device to transmit a data frame to the second initiating device. The communication unit 1501 is further configured to transmit a data frame based on the fourth delay information for the first responding device to transmit a data frame to the second initiating device, the data frame including the time for the first responding device to receive a plurality of second orthogonal UWB segment signals and the time for the first responding device to transmit a plurality of third orthogonal UWB segment signals.

[0346] In one further possible design, the communication device 1500 includes a processing unit 1502 and a communication unit 1501. The processing unit 1502 is configured to control the communication unit 1501 to perform data / signaling reception and transmission. The communication unit 1501 is configured to transmit a polling frame. The polling frame includes time-frequency position information for N ultra-wideband (UWB) segment signal groups. The polling frame includes time-frequency position information for N ultra-wideband (UWB) segment signal groups, a first response time for X second initiating devices to reply to the control device in a response frame, a subcarrier set for all X second initiating devices to reply to the control device in a response frame, a second response time for M second responding devices to reply to the control device in a response frame, and a subcarrier set for all M second responding devices to reply to the control device in a response frame, where N, M, and X are integers greater than or equal to 2.

[0347] The communication unit 1501 is further configured to receive a second response frame based on the same second response time for M second response devices to reply to the control device in response frames, and a set of subcarriers for all second response devices to reply to the control device in response frames, wherein the second response frame includes a plurality of second response signals, and to receive a first response frame based on the same first response time for X second initiating devices to reply to the control device in response frames, and a set of subcarriers for all second initiating devices to reply to the control device in response frames, wherein the first response frame includes a plurality of first response signals.

[0348] In one optional implementation, the polling frame further includes the orthogonal sequence index of each second initiating device, the orthogonal sequence index of each of the M second responding devices, and identical third delay information for all second responding devices to respond to the first UWB segment signal from the first initiating device.

[0349] In one implementation of another option, the polling frame further includes the data frame time for which M second responding devices transmit data frames to the second initiating device, and the set of subcarriers for all M second responding devices to transmit data frames to the second initiating device.

[0350] This embodiment of this application and the method embodiment described above are based on the same concept and produce the same technical effects. For specific principles, please refer to the description of the embodiment described above. Details will not be explained again.

[0351] In one further possible design, the communication device 1500 includes a processing unit 1502 and a communication unit 1501. The processing unit 1502 is configured to control the communication unit 1501 to perform data / signaling reception and transmission. The communication unit 1501 is configured to receive a polling frame. The polling frame includes time-frequency position information of N ultra-wideband (UWB) segment signal groups, the same first response time which X second initiating devices send back to the control device in response frames, and a set of subcarriers for all X second initiating devices to send back to the control device in response frames, where the first initiating device is any one of the X second initiating devices, and N and X are integers greater than or equal to 2. The communication unit 1501 is further configured to transmit a first response signal based on the first response time and the set of subcarriers for the first initiating devices to send back to the control device in response frames.

[0352] In one optional implementation, the polling frame further includes the orthogonal sequence index of each second initiating device, the orthogonal sequence index of each of the M second responding devices, and identical third delay information for all second responding devices to reply to the first UWB segment signal from the second initiating device, where M is an integer greater than or equal to 2. The communication unit 1501 is further configured to transmit N second orthogonal UWB segment signals separately based on the time-frequency position information of N first UWB segment signal groups and the orthogonal sequence index of the first initiating device, and to receive a plurality of third orthogonal UWB segment signals separately based on the third delay information and the orthogonal sequence index of each second responding device.

[0353] In one optional implementation, the polling frame further includes the same data frame time for all second responding devices to transmit the data frame to the first initiating device, and a set of subcarriers for all second responding devices to transmit the data frame to the first initiating device. The communication unit 1501 is further configured to receive a data frame based on the above data frame time and the set of subcarriers for all second responding devices to transmit the data frame to the first initiating device, the data frame comprising a plurality of data signals, each of which comprises the time for the first responding device to receive a plurality of second orthogonal UWB segment signals and the time for the first responding device to transmit a plurality of third orthogonal UWB segment signals, the first responding device being any one of M second responding devices.

[0354] This embodiment of this application and the method embodiment described above are based on the same concept and produce the same technical effects. For specific principles, please refer to the description of the embodiment described above. Details will not be explained again.

[0355] In one further possible design, the communication device 1500 includes a processing unit 1502 and a communication unit 1501. The processing unit 1502 is configured to control the communication unit 1501 to perform data / signaling reception and transmission. The communication unit 1501 is configured to receive a polling frame. The polling frame includes time-frequency position information of N ultra-wideband (UWB) segment signal groups, identical second response times for M second responding devices to reply to the control device in response frames, and a set of subcarriers for all M second responding devices to reply to the control device in response frames, where N and M are integers greater than or equal to 2, and the first responding device is any one of the M second responding devices. The communication unit 1501 is further configured to transmit a second response signal based on the second response times and the set of subcarriers for the first responding devices to reply to the control device in response frames.

[0356] In one optional implementation, the polling frame further includes the orthogonal sequence index of each of X second initiating devices, the orthogonal sequence index of each second responding device, and identical third delay information for all second responding devices to respond to a first UWB segment signal from a first initiating device, where the first initiating device is any one of the X second initiating devices, and M is an integer greater than or equal to 2. The communication unit 1501 is further configured to receive a plurality of second orthogonal UWB segment signals based on time-frequency position information of N UWB segment signal groups and the orthogonal sequence index of each second initiating device, and to transmit a plurality of third orthogonal UWB segment signals separately based on the third delay information and the orthogonal sequence index of the first responding device.

[0357] In one implementation of another option, the polling frame further includes the same data frame time for all second responding devices to transmit data frames to the first initiating device, and a set of subcarriers for all second responding devices to transmit data frames to the first initiating device. The communication unit 1501 is further configured to transmit a data signal based on the above data frame time and the set of subcarriers for the first responding devices to transmit data frames to the first initiating device, the data signal including the time for the first responding device to receive a plurality of second orthogonal UWB segment signals and the time for the first responding device to transmit a plurality of third orthogonal UWB segment signals.

[0358] This embodiment of this application and the method embodiment described above are based on the same concept and produce the same technical effects. For specific principles, please refer to the description of the embodiment described above. Details will not be explained again.

[0359] One embodiment of this application further provides a communication device 1600. Figure 16 is a diagram of the configuration of the communication device 1600. The communication device 1600 may be a first initiator, a first response device, or a control device, or it may be a chip, chip system, or processor, etc., that supports the first initiator, first response device, or control device when carrying out the method described above. The device may be configured to carry out the method described in the method embodiment described above. For further details, please refer to the description in the method embodiment described above.

[0360] The communication device 1600 may include one or more processors 1601. The processors 1601 may be general-purpose processors, dedicated processors, or similar. For example, the processor may be a baseband processor, a digital signal processor, an application-specific integrated circuit, a field-programmable gate array or other programmable logic device, a discrete gate or transistor logic device, a discrete hardware component, or a central processing unit (CPU). The baseband processor may be configured to process communication protocols and communication data. The central processing unit may be configured to control the communication device (e.g., a base station, a baseband chip, a terminal, a terminal chip, a distributed unit (DU), or a central unit (CU)), execute software programs, and process data from the software programs.

[0361] Optionally, the communication device 1600 may include one or more memories 1602. The memories 1602 store instructions 1604, which are executed on the processor 1601, enabling the communication device 1600 to perform the method described in the above-described embodiment. Optionally, the memories 1602 may store further data. The processor 1601 and the memories 1602 may be located separately or integrated together.

[0362] Memory 1602 may include, but is not limited to, non-volatile memory such as hard disk drives (HDDs) or solid-state drives (SSDs), random access memory (RAM), erasable programmable ROM (EPROM), ROM, or compact disc read-only memory (CD-ROM).

[0363] Optionally, the communication device 1600 may further include a transceiver 1605 and an antenna 1606. The transceiver 1605 may also be called a transceiver unit, transceiver machine, or transceiver circuit, and is configured to implement transceiver functionality. The transceiver 1605 may include a receiver and a transmitter. The receiver may also be called a receiver machine or receiver circuit, and is configured to implement receiving functionality. The transmitter may also be called a transmitter machine or transmitter circuit, and is configured to implement transmitting functionality.

[0364] When the communication device 1600 is the first initiating device, the transceiver 1605 is configured to perform S101, S104, S105, and S108 in the signal transmission method 100, S201, S204, S205, and S208 in the signal transmission method 200, S302, S304, S307, and S310 in the signal transmission method 300, and S402, S404, S408, and S411 in the signal transmission method 400.

[0365] When the communication device 1600 is the first response device, the transceiver 1605 is configured to perform S102, S103, S106, and S107 in the signal transmission method 100, S202, S203, S206, and S207 in the signal transmission method 200, S303, S305, S308, and S309 in the signal transmission method 300, and S403, S405, S409, and S410 in the signal transmission method 400.

[0366] When the communication device 1600 is a control device, the transceiver 1605 is configured to execute S301 and S306 in the signal transmission method 300, and to execute S401, S406, and S407 in the signal transmission method 300.

[0367] In another possible design, the processor 1601 may include a transceiver configured to implement receiving and transmitting functions. For example, the transceiver may be a transceiver circuit, interface, or interface circuit. The transceiver circuit, interface, or interface circuit configured to implement receiving and transmitting functions may be separate or integrated together. The transceiver circuit, interface, or interface circuit may be configured to read or write code / data, or the transceiver circuit, interface, or interface circuit may be configured to perform signal transmission or transfer.

[0368] In one further possible design, the processor 1601 may optionally store instruction 1603, and the execution of instruction 1603 on the processor 1601 allows the communication device 1600 to execute the method described in the above-described embodiment. Instruction 1603 may be fixed to the processor 1601, in which case the processor 1601 may be implemented using hardware.

[0369] In yet another possible design, the communication device 1600 may include a circuit that can implement the transmit, receive, or communicate functions in the method embodiments described above. The processors and transceivers described in embodiments of this application may be mounted on integrated circuits (ICs), analog ICs, radio frequency integrated circuits (RFICs), mixed-signal ICs, application-specific integrated circuits (ASICs), printed circuit boards (PCBs), or electronic devices. Alternatively, the processors and transceivers may be manufactured using various IC process technologies, such as complementary metal oxide semiconductors (CMOS), N-type metal oxide semiconductors (NMOS), P-type metal oxide semiconductors (PMOS), bipolar junction transistors (BJTs), bipolar CMOS (BiCMOS), silicon germanium (SiGe), and gallium arsenide (GaAs).

[0370] The communication device described in the embodiments described above may be a first communication device or a second communication device. However, the scope of the communication device described in the embodiments of this application is not limited thereto, and the configuration of the communication device may not be limited by Figure 16. The communication device may be a standalone device or part of a larger device. For example, the communication device may be: (1) an independent integrated circuit (IC), chip, or chip system or subsystem; (2) A set having one or more ICs, which may optionally include a storage component configured to store data and instructions instead; (3) ASICs such as modems (modulators); (4) Modules that can be incorporated into other devices; (5) Receivers, terminals, intelligent terminals, cellular telephones, wireless devices, handheld devices, mobile units, in-vehicle devices, network devices, cloud devices, artificial intelligence devices, or similar items, (6) Others It can be.

[0371] If the communication device can be a chip or a chip system, refer to the chip configuration diagram shown in Figure 17. The chip 1700 shown in Figure 17 includes a processor 1701 and an interface 1702. There may be one or more processors 1701 and multiple interfaces 1702. The processor 1701 can be a logic circuit, and the interface 1702 can be an input / output interface, an input interface, or an output interface. The chip 1700 may further include a memory 1703.

[0372] Details of a design in which the chip is configured to implement the functions of the first initiation device in an embodiment of this application are as follows: The processor 1701 is configured to control the interface 1702 to output or receive.

[0373] Interface 1702 is configured to transmit polling frames. The polling frames include time-frequency position information for N first ultra-wideband (UWB) segment signals and first delay information for each of M second responding devices to reply to the first initiating device in a response frame, where N and M are integers greater than or equal to 2. Interface 1702 is further configured to receive a plurality of response frames based on the timestamp of the polling frame and the first delay information for each second responding device to reply to the first initiating device in a response frame.

[0374] In another design, where the chip is configured to implement the functionality of the first responding device in this embodiment, further details are provided below. Interface 1702 is configured to receive a polling frame, which has time-frequency position information for N first ultra-wideband (UWB) segment signals and first delay information for each of M second responding devices to reply to the first initiating device in a response frame, where N and M are integers greater than or equal to 2, and the first responding device is any one of the M second responding devices. Interface 1702 is further configured to send a response frame to the first initiating device based on the timestamp of the polling frame and the first delay information for the first responding device to reply to the first initiating device in a response frame.

[0375] Further details regarding a design in which the chip is configured to implement the functionality of the first initiation device in this embodiment of the application are as follows:

[0376] Interface 1702 is configured to transmit a polling frame. The polling frame includes time-frequency position information of N first ultra-wideband (UWB) segment signals, the same response time for M second responding devices to reply to the first initiating device in response frames, and a set of subcarriers for all M second responding devices to reply to the first initiating device in response frames, wherein the narrowband signal transmitted during the response time includes multiple subcarriers, and N and M are integers greater than or equal to 2. Interface 1702 is further configured to receive a response frame based on the response time and the set of subcarriers for all second responding devices to reply to the first initiating device in response frames, wherein the response frame includes multiple response signals.

[0377] Further details regarding a design in which the chip is configured to implement the functionality of the first response device in this embodiment are as follows:

[0378] Interface 1702 is configured to receive a polling frame. The polling frame includes time-frequency position information of N first ultra-wideband (UWB) segment signals, the same response time for M second responding devices to reply to the first initiating device in a response frame, and a set of subcarriers for all of the M second responding devices to reply to the first initiating device in a response frame, wherein the narrowband signal transmitted during the response time includes multiple subcarriers, and N and M are integers greater than or equal to 2. Interface 1702 is further configured to transmit a response signal to the first initiating device based on the response time and the set of subcarriers for the first responding devices to reply to the first initiating device in a response frame, wherein the first responding device is any one of the M second responding devices.

[0379] Details regarding another design in which the chip is configured to implement the functions of the control device in the embodiment of this application are as follows:

[0380] Interface 1702 is configured to transmit a polling frame. The polling frame includes time-frequency position information for N ultra-wideband (UWB) segment signal groups, first delay information for each of M second response devices to reply to the control device in a response frame, and fifth delay information for each of X second initiating devices to reply to the control device in a response frame, where N, M, and X are integers of 2 or greater. Interface 1702 is further configured to receive multiple response frames based on a plurality of first delay information, a plurality of fifth delay information, and a timestamp of the polling frame.

[0381] Further details regarding a design in which the chip is configured to implement the functionality of the first initiation device in this embodiment of the application are as follows:

[0382] Interface 1702 is configured to receive polling frames. The polling frames include time-frequency position information for N ultra-wideband (UWB) segment signal groups and fifth delay information for each of X second initiating devices to reply to the control device in a response frame, where the first initiating device is any one of the X second initiating devices, and N and X are integers greater than or equal to 2. Interface 1702 is further configured to transmit response frames based on the timestamp of the polling frame and the fifth delay information for the first initiating device to reply to the control device in a response frame.

[0383] Further details regarding a design in which the chip is configured to implement the functionality of the first response device in this embodiment are as follows:

[0384] Interface 1702 is configured to receive polling frames. The polling frames include time-frequency position information for N ultra-wideband (UWB) segment signal groups and first delay information for each of M second responding devices to reply to the control device in a response frame, where the first responding device is any one of the M second responding devices, and N and M are integers greater than or equal to 2. Interface 1702 is further configured to transmit response frames based on the timestamp of the polling frame and the first delay information for the first responding device to reply to the control device in a response frame.

[0385] Further details regarding a design in which the chip is configured to implement the functions of the control device in this embodiment of the application are as follows:

[0386] Interface 1702 is configured to transmit a polling frame. The polling frame includes time-frequency position information for N ultra-wideband (UWB) segment signal groups. The polling frame includes time-frequency position information for N ultra-wideband (UWB) segment signal groups, identical second response times for M second responding devices to send back to the control device in response frames, a set of subcarriers for all M second responding devices to send back to the control device in response frames, identical first response times for X second initiating devices to send back to the control device in response frames, and a set of subcarriers for all X second initiating devices to send back to the control device in response frames, wherein the narrowband signal transmitted in response time includes multiple subcarriers, and N, M, and X are integers greater than or equal to 2.

[0387] Interface 1702 is further configured to receive a second response frame based on M second response devices sending a response frame back to the control device, and a set of subcarriers for all second response devices to send a response frame back to the control device, wherein the second response frame includes a plurality of second response signals, and to receive a first response frame based on X second start devices sending a response frame back to the control device, and a set of subcarriers for all second start devices to send a response frame back to the control device, wherein the first response frame includes a plurality of first response signals.

[0388] Further details regarding a design in which the chip is configured to implement the functionality of the first initiation device in this embodiment of the application are as follows:

[0389] Interface 1702 is configured to receive a polling frame. The polling frame includes time-frequency position information for N ultra-wideband (UWB) segment signal groups, the same first response time for X second initiating devices to send back to the control device in a response frame, and a set of subcarriers for all X second initiating devices to send back to the control device in a response frame, where the first initiating device is any one of the X second initiating devices, and N and X are integers greater than or equal to 2. Interface 1702 is further configured to transmit a first response signal based on the first response time and the set of subcarriers for the first initiating devices to send back to the control device in a response frame.

[0390] Further details regarding a design in which the chip is configured to implement the functionality of the first response device in this embodiment are as follows:

[0391] Interface 1702 is configured to receive a polling frame. The polling frame includes time-frequency position information for N ultra-wideband (UWB) segment signal groups, identical second response times for M second response devices to send back to the control device in response frames, and a set of subcarriers for all M second response devices to send back to the control device in response frames, where N and M are integers greater than or equal to 2, and the first response device is any one of the M second response devices. Interface 1702 is further configured to transmit a second response signal based on the second response times and the set of subcarriers for the first response devices to send back to the control device in response frames.

[0392] In embodiments of this application, the communication device 1600 and the chip 1700 may further implement the communication device 1500. Those skilled in the art will further understand that the various illustrative logical blocks and steps enumerated in embodiments of this application may be implemented using electronic hardware, computer software, or a combination thereof. Whether a function is implemented using hardware or software depends on the specific application and the design requirements of the overall system. Those skilled in the art should not consider that, for each specific application, the described functions can be implemented in various ways, and that such implementations exceed the scope of the embodiments of this application.

[0393] This embodiment of this application, and the method embodiments shown in signal transmission methods 100 to 400, are based on the same concept and produce the same technical effects. For specific principles, please refer to the description of the embodiments shown in signal transmission methods 100 to 400. Details will not be explained again here.

[0394] This application further provides a computer-readable storage medium configured to store computer software instructions. When the instructions are executed by a communication device, the functions of any of the above-described method embodiments are performed.

[0395] This application further provides a computer program product configured to store computer software instructions. When the instructions are executed by a communication device, the functions of any of the above-described embodiments of the method are performed.

[0396] This application further provides a computer program. When the computer program is executed on a computer, the functions of any of the above-described embodiments of the method are performed.

[0397] This application further provides a communication system comprising at least one first initiating device and at least two first responding devices in the embodiments described above. In one other possible design, the system may further include another device that interacts with the first initiating device and the first responding devices in the solution provided in this application.

[0398] All or part of the embodiments described above may be implemented using software, hardware, firmware, or any combination thereof. When software is used to implement an embodiment, all or part of the embodiment may be implemented in the form of a computer program product. A computer program product includes one or more computer instructions. When the computer instructions are loaded onto a computer and executed, all or part of the procedures or functions according to the embodiments of this application are generated. The computer may be a general-purpose computer, a dedicated computer, a computer network, or other programmable device. The computer instructions may be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another. For example, computer instructions may be transmitted by wired means (e.g., coaxial cable, optical fiber, or digital subscriber line (DSL)) or wireless means (e.g., infrared, radio waves, or microwaves) from one website, computer, server, or data center to another website, computer, server, or data center. Computer-readable storage media can be any available medium accessible by a computer, or they can be a data storage device that integrates one or more available media, such as a server or data center. Available media can be magnetic media (e.g., floppy disks, hard disks, or magnetic tapes), optical media (e.g., high-density digital video discs (DVDs)), semiconductor media (e.g., SSDs), or similar.

[0399] The above description is merely a specific implementation of this application and is not intended to limit the scope of protection of this application. Any modification or substitution that a person skilled in the art can easily conceive within the scope of the technical scope disclosed in this application is also within the scope of protection of this application. Accordingly, the scope of protection of this application is subject to the scope of protection of the claims.

Claims

1. A signal transmission method, A first initiating device transmits a polling frame, the polling frame having first delay information for each of M second responding devices to reply to the first initiating device in a response frame, the M second responding devices including second responding device #1 and second responding device #M, where M is an integer of 2 or more. The first initiating device receives a plurality of response frames based on the timestamp of the polling frame and the first delay information for each second responding device to reply to the first initiating device in the response frame. A method having the following characteristics.

2. After receiving the aforementioned plurality of response frames, the method further: The first start device transmits the first UWB segment signal #1 based on the time-frequency position information of the first UWB segment signal #1. The first initiating device separately receives the second UWB segment signal #1 from the second responding device #1 and the second UWB segment signal #M from the second responding device #M. Having, The transmission time of the second UWB segment signal #1 is different from the transmission time of the second UWB segment signal #M. The method according to claim 1.

3. After receiving the aforementioned plurality of response frames, the method further: The first start device transmits the first UWB segment signal #1 based on the time-frequency position information of the first UWB segment signal #1. The first start device receives a first orthogonal UWB segment signal #1 from the second response device #1 and a first orthogonal UWB segment signal #M from the second response device #M, based on the third delay information, the orthogonal sequence index of the second response device #1, and the orthogonal sequence index of the second response device #M. Having, The transmission time of the first orthogonal UWB segment signal #1 is the same as the transmission time of the first orthogonal UWB segment signal #M. The method according to claim 1.

4. The first start device is active when it transmits the first UWB segment signal #1 and receives the first orthogonal UWB segment signal #1 and the first orthogonal UWB segment signal #M. The method according to claim 3.

5. After the first initiating device receives the UWB segment signal returned in response to the first UWB segment signal #1, the method further: The first initiating device separately receives data frame #1 from the second response device #1 and data frame #M from the second response device #M. Having, The transmission time of data frame #1 is different from the transmission time of data frame #M. The method according to claim 2.

6. The data frame #1 includes the time when the second response device #1 received the first UWB segment signal #1, and the time when the second response device #1 transmitted the second UWB segment signal #1, or The data frame #M includes the time when the second response device #M received the first UWB segment signal #1, and the time when the second response device #M transmitted the second UWB segment signal #M. The method according to claim 5.

7. The data frame #1 includes the time when the second response device #1 received the first UWB segment signal #1, and the time when the second response device #1 transmitted the first orthogonal UWB segment signal #1, or The data frame #M includes the time when the second response device #M received the first UWB segment signal #1, and the time when the second response device #M transmitted the first orthogonal UWB segment signal #M. The method according to claim 5.

8. The first initiating device transmits the first UWB segment signal #1 based on the time-frequency position information of the first UWB segment signal #1, When the first timer has not expired and the first start device has received M response frames, the first start device transmits the first UWB segment signal #1 based on the time-frequency position information of the first UWB segment signal #1, or When the first start device has received S response frames and the first timer has expired, the first start device transmits the first UWB segment signal #1 based on the time-frequency position information of the first UWB segment signal #1. Having, The first timer is triggered when the polling frame is transmitted, and S is an integer greater than or equal to 1 and less than M. The method according to claim 2.

9. A signal transmission method, A first response device receives a polling frame, the polling frame having first delay information for each of M second response devices to reply to the first initiator in a response frame, the first response device being any one of the M second response devices, where M is an integer of 2 or more. The first response device transmits a response frame to the first start device based on the timestamp of the polling frame and first delay information for the first response device to reply to the first start device in the response frame. A method having the following characteristics.

10. After transmitting the response frame to the first initiation device, the method further: The first response device receives the first UWB segment signal based on the time-frequency position information of the first UWB segment signal. The first response device transmits a second UWB segment signal to the first start device based on the second delay information. The method according to claim 9, wherein the method is as follows:

11. After transmitting the response frame to the first initiation device, the method further: The first response device receives the first UWB segment signal based on the time-frequency position information of the first UWB segment signal. The first response device transmits a first orthogonal UWB segment signal to the first start device based on third delay information, and the first orthogonal UWB segment signal is determined based on the orthogonal sequence index of the first response device. The method according to claim 9, wherein the method is as follows:

12. After transmitting the UWB segment signal to the first start device, the method further: The first response device transmits the data frame to the first start device based on a fourth delay information that the first response device uses to transmit the data frame to the first start device. The method according to claim 10, wherein the above is achieved.

13. The data frame includes the time the first response device received the first UWB segment signal and the time the first response device transmitted the second UWB segment signal. The method according to claim 12.

14. The data frame includes the time the first response device received the first UWB segment signal and the time the first response device transmitted the first orthogonal UWB segment signal. The method according to claim 12.

15. A communication device having a module configured to perform the method described in any one of claims 1 to 8, or a module configured to perform the method described in any one of claims 9 to 14.

16. A communication device having a processor, wherein the processor is configured to perform the method described in any one of claims 1 to 8, or to perform the method described in any one of claims 9 to 14.

17. A chip having at least one processor, wherein the processor executes instructions, enabling a communication device having the chip to perform the method according to any one of claims 1 to 8 or the method according to any one of claims 9 to 14.

18. The chip according to claim 17, further comprising an interface circuit configured to receive the instruction to be executed and to transmit the instruction to be executed to the processor.

19. A computer-readable storage medium configured to store instructions, wherein when the instructions are executed on a communication device, the method described in any one of claims 1 to 8 or the method described in any one of claims 9 to 14 is performed.

20. A computer program having instructions, wherein when the instructions are executed on a communication device, the method described in any one of claims 1 to 8 or the method described in any one of claims 9 to 14 is performed.

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