Communication method and apparatus, and device and storage medium

Abstract

The present application relates to the technical field of communications. Disclosed are a communication method and apparatus, and a device and a storage medium. The method comprises: a network device receiving at least one first message, which first message indicates whether frequency offset is supported and / or indicates a supported frequency offset range, and sending a second message, which second message indicates whether to perform frequency offset and / or indicates a frequency offset amount, and / or indicates a time-domain resource; and a terminal device sending a third message, wherein when the second message instructs the terminal device to perform frequency offset and indicates the time-domain resource, the third message is carried on a time-frequency resource determined on the basis of the second message, otherwise the third message is carried on a frequency-domain resource and / or time-domain resource carrying the first message. In this way, a reader can more efficiently and reasonably use time-domain and frequency-domain resources to complete the process of a plurality of A-IoT devices accessing the reader, and the impact of interference on the signal quality of the reader can also be reduced, thereby facilitating the demodulation of Msg3 by means of the reader.

Description

A communication method, apparatus, device, and storage medium

[0001] This application claims priority to Chinese Patent Application No. 202510128218.3, filed on January 27, 2025, entitled "A Communication Method, Apparatus, Device and Storage Medium", the entire contents of which are incorporated herein by reference. Technical Field

[0002] This application relates to the field of communication technology, and in particular to a communication method, apparatus, device and storage medium. Background Technology

[0003] With the widespread application of IoT technology, a massive number of IoT devices will be connected in the future. As a result, the Ambient Internet of Things (A-IoT) has emerged.

[0004] In IoT scenarios, readers can trigger a Random Access (RA) process, which is used for A-IoT devices to access the network for data transmission. During the RA process, the A-IoT device and the reader can exchange four messages (Msg): Message 1 (Msg1), Message 2 (Msg2), Message 3 (Msg3), and Message 4 (Msg4). Among these, Msg3 is for uplink transmission and requires uplink scheduling resources. How to configure the time and frequency domain resources of Msg3 to fully and flexibly utilize these resources is a problem that needs to be solved. Summary of the Invention

[0005] This application provides a communication method, apparatus, device, and storage medium capable of configuring the time-domain and frequency-domain resources of Msg3, thus fully and flexibly utilizing these resources. The technical solution is as follows:

[0006] In a first aspect, embodiments of this application provide a communication method applied to network devices in an environmental Internet of Things (IoT) environment. The network device can be a base station, which can provide reader functionality. In this method, the network device receives at least one first message. The first message reports whether a terminal device supports frequency offset and / or a supported frequency offset range. The frequency offset is an offset relative to the frequency domain resource location carrying the first message. The network device sends a second message, indicating whether the terminal device performs frequency offset and / or the amount of frequency offset, and / or indicating time domain resources, which are different from the time domain resources carrying the first message. Upon receiving the second message, the terminal device can send a third message according to the indication of the second message. Thus, when the network device receives the third message, if the second message indicates that the terminal device performs frequency offset and indicates time domain resources, the third message carries the time-frequency resources determined based on the second message. If the second message does not indicate that the terminal device performs frequency offset and / or time domain resources, the third message carries the frequency domain resources and / or time domain resources carrying the first message.

[0007] The aforementioned first, second, and third messages are used for one uplink synchronization of the terminal device. The first message can be Msg1 in the four-step random access process, the second message can be Msg2 in the four-step random access process, and the third message can be Msg3 in the four-step random access process. The terminal device reports frequency offset capability through Msg1, and the reader / writer uses Msg2 to indicate whether there is frequency offset, the frequency offset value, time domain resources, or one or more other information to configure the frequency domain resources and / or time domain resources of Msg3, thereby achieving flexible configuration of Msg3. Since the time domain and frequency domain resources allocated by the base station to multiple A-IoT devices in the A-IoT scenario are limited, the method provided in this application embodiment allows the reader / writer to utilize the time domain and frequency domain resources more efficiently and reasonably by flexibly configuring the frequency domain and time domain resources of Msg3, completing the process of multiple A-IoT devices accessing the reader / writer.

[0008] Due to the complex operating environment of IoT systems, and the fact that A-IoT devices are simple, low-cost hardware communication devices, they are prone to mutual interference when transmitting Msg3. The method provided in this application involves the reader instructing the A-IoT device to perform a frequency shift via Msg2. When transmitting Msg3, the A-IoT device can perform a certain frequency shift. By appropriately shifting the frequency, the spectrum is fully utilized, and the Msg3 transmitted by different A-IoT devices are as far apart as possible in the frequency domain, avoiding mutual interference, reducing the impact of interference on the reader's signal quality, and facilitating the demodulation of Msg3 by the reader.

[0009] In conjunction with the first aspect, in certain implementations of the first aspect, the message content of the first message, or the time-frequency position of the first message, or the random sequence corresponding to the first message, indicates whether the terminal device supports frequency offset and / or the supported frequency offset range. Thus, the terminal device can indicate whether it supports frequency offset and / or the supported frequency offset range through the message content of Msg1. For example, the message content may include a first field, the value of which can indicate whether the A-IoT device supports frequency offset. Alternatively, the terminal device can indicate whether it supports frequency offset and / or the supported frequency offset range by sending the time-frequency position of Msg1. Or, the terminal device can indicate whether it supports frequency offset and / or the supported frequency offset range through the random sequence corresponding to Msg1.

[0010] When Msg1 indicates that the terminal device only supports frequency offset, the reader can configure the frequency offset for the terminal device from a predefined frequency offset range. When Msg1 indicates that the terminal device does not support frequency offset, the corresponding Msg3 reuses the frequency domain configuration of Msg1.

[0011] In conjunction with the first aspect, in some implementations of the first aspect, the frequency offset range includes: multiple frequency offsets, frequency offset range groups, or the maximum value of the frequency offset. Thus, the first message can indicate the frequency offset range supported by the reporting terminal device, for example, reporting multiple frequency offsets supported by the terminal device, or reporting frequency offset range groups supported by the terminal device, or reporting the maximum value of the frequency offset supported by the terminal device. Accordingly, the reader determines the frequency offset range supported by the terminal device, the frequency offset indicated by the second message does not exceed the range reported by Msg1, and the frequency offset range sent by the terminal device in the third message does not exceed the reported capability range.

[0012] Optionally, in some implementations of the first aspect, Msg1 may report the frequency range supported by the terminal device.

[0013] In conjunction with the first aspect, in some implementations of the first aspect, the start indicator or clock acquisition portion of the second message indicates whether the terminal device performs a frequency offset.

[0014] In conjunction with the first aspect, in some implementations of the first aspect, when the start indicator or clock acquisition part of the second message instructs the terminal device to perform a frequency offset, the message content of the second message may indicate the frequency offset amount.

[0015] In conjunction with the first aspect, in some implementations of the first aspect, when the start indicator or clock acquisition part of the second message instructs the terminal device to perform a frequency offset, and the message content of the second message does not indicate the frequency offset, the frequency offset corresponding to the terminal device is a predefined value.

[0016] In this way, after receiving the second message, the terminal device can determine whether to perform a frequency offset based on the start indicator or the clock acquisition section. If a frequency offset is performed, the terminal device can obtain the frequency offset amount from the message content of the second message. If the message content of the second message does not indicate a frequency offset amount, the terminal device can perform a frequency offset based on a predefined value.

[0017] In conjunction with the first aspect, in some implementations of the first aspect, the duration of the high and low levels corresponding to the start indicator of the second message indicates whether the terminal device performs a frequency shift.

[0018] In conjunction with the first aspect, in some implementations of the first aspect, whether the total duration of the high level and the total duration of the low level corresponding to the start indicator of the second message are the same indicates whether the terminal device should perform frequency shifting; or, whether the duration of the high level and the duration of the low level of the i-th level segment corresponding to the start indicator of the second message are the same indicates whether the terminal device should perform frequency shifting, where i is an integer ≥ 1. For example, when the total duration of the high level and the total duration of the low level of the start indicator are the same, it indicates that no frequency shifting should be performed; when the total duration of the high level and the total duration of the low level are different, it indicates that frequency shifting should be performed. For example, when the duration of the high level and the duration of the low level of the i-th level segment are the same, it indicates that no frequency shifting should be performed; when the duration of the high level and the duration of the low level of the i-th level segment are different, it indicates that frequency shifting should be performed. After receiving the second message, the terminal device can determine whether to perform frequency shifting based on the duration of the high level and the low level.

[0019] In conjunction with the first aspect, in some implementations of the first aspect, the M value corresponding to the clock acquisition portion of the second message indicates whether the terminal device should perform a frequency shift. The duration of the clock acquisition portion varies with the M value; for example, the duration shortens as the M value increases. Different M values ​​are predefined to correspond to either not performing a frequency shift or performing a frequency shift. For example, a large M value indicates that the A-IoT device should not perform a frequency shift; a small M value indicates that the A-IoT device should perform a frequency shift. The network device can instruct the terminal device whether to perform a frequency shift based on the magnitude of the M value. Correspondingly, the terminal device can determine whether to perform a frequency shift based on the magnitude of the M value.

[0020] Alternatively, the M-value and repetition factor corresponding to the clock acquisition section of the second message indicate whether the terminal device should perform frequency offset. There can be multiple combinations of M-value and repetition factor, and different combinations of M-value and repetition factor may indicate that the A-IoT device should not perform frequency offset, or that the A-IoT device should perform frequency offset.

[0021] In conjunction with the first aspect, in some implementations of the first aspect, the M value corresponding to the clock acquisition part of the second message instructing the terminal device to perform frequency offset includes: the M value corresponding to the clock acquisition part of the second message instructing the frequency offset range grouping; or, the M value corresponding to the clock acquisition part of the second message and the repetition factor instructing the terminal device to perform frequency offset includes: the M value corresponding to the clock acquisition part of the second message and the repetition factor instructing the frequency offset range grouping.

[0022] In conjunction with the first aspect, in some implementations of the first aspect, when the message content of the second message includes multiple frequency offsets, the multiple frequency offsets are ordered according to a random identifier.

[0023] When the reader receives a Msg1 and replies with a Msg2, the reader can provide different instructions for different A-IoT devices. For example, for A-IoT device 1, the frequency offset is indicated by the aforementioned start indicator or clock acquisition section of Msg2, and the message content of Msg2 indicates the corresponding frequency offset amount for A-IoT device 1. For A-IoT device 2, no frequency offset is indicated by the aforementioned start indicator or clock acquisition section.

[0024] When the reader receives multiple Msg1 responses along with a single Msg2, it broadcasts a Msg2 message to multiple A-IoT devices. The start indicator or clock acquisition portion of Msg2 uniformly instructs the multiple A-IoT devices whether to perform frequency offset. The message content of Msg2 indicates the frequency offset for each A-IoT device, and these offsets can be ordered according to the random IDs of the A-IoT devices. Correspondingly, the terminal device can determine its own frequency offset based on its own random identifier.

[0025] In conjunction with the first aspect, in some implementations of the first aspect, the start indicator or clock acquisition portion of the second message indicates the frequency offset. Accordingly, the message content of the second message may not carry the frequency offset.

[0026] In conjunction with the first aspect, in some implementations of the first aspect, the frequency offset includes one of the following: a frequency offset value, an identifier of the frequency offset value, and a coefficient of the frequency offset, wherein the coefficient is an integer multiple of the minimum chip length corresponding to the message encoding method.

[0027] In conjunction with the first aspect, in some implementations of the first aspect, the time-domain resources include at least one of the following: time slot length and guard interval length, time-domain start time, and time-domain end time. The time-domain length is the duration for transmitting valid data. The guard interval length is the time interval between two Msg3 time intervals received by the base station, used to avoid inter-symbol interference. The time slot length supports multiple different length values, and the guard interval length also supports multiple different length values.

[0028] When indicating time-domain resources, network devices can specify the time slot length, time-domain start time, and time-domain end time occupied by the Msg3 resource in the second message. Alternatively, they can specify the time slot length and time-domain start time of Msg3 in the second message. After receiving Msg2, the terminal device can determine its own time-domain resources based on the indications in Msg2. By reconfiguring time-domain resources, Msg3 can occupy a longer time-domain resource length to carry more information and reduce time-domain resource waste; it can also reduce interference by increasing the length of the guard interval.

[0029] Optionally, the time-domain start time can be represented by the start time slot position, and the time-domain end time can be represented by the end time slot position. The start time slot position and / or end time slot position of the time-domain resource indicated by Msg2 can be a value based on a reference position, such as the clock start position, the end / start position of the start indicator, the end position of the clock acquisition section, etc.

[0030] The start and / or end timeslot positions of the time-domain resources indicated by Msg2 can also be relative values ​​to the resource timeslot positions of Msg1. The network device and the terminal device know the value of each Msg1 resource timeslot position relative to a reference position (denoted as value 1). Msg2 indicates the relative value of the resource timeslot position of Msg3 relative to the resource timeslot position of Msg1 (denoted as value 2). The terminal device can determine the resource timeslot position of Msg3 based on value 1 and value 2. For example, if the resource of Msg1 is the third resource in time-domain order, after receiving the indication of Msg2, the terminal device can calculate the corresponding resource position of Msg3 as the first resource in time-domain order by using value 2.

[0031] Optionally, in some implementations, the second message may indicate whether the terminal device performs a time-domain offset and / or a time-domain offset amount. A time-domain offset is an offset from the time-domain resource location where the message sent by the terminal device is located. Time-domain resources can be represented by REs or time slots.

[0032] In conjunction with the first aspect, in certain implementations of the first aspect, the message content of the first message, or the time-frequency position of the first message, or the random sequence corresponding to the first message, indicates whether the terminal device supports time-domain offset and / or the supported time-domain offset range. Thus, the terminal device can indicate whether it supports time-domain offset and / or the supported time-domain offset range through the message content of Msg1. For example, the message content may include a first field, the value of which can indicate whether the A-IoT device supports time-domain offset. Alternatively, the terminal device can indicate whether it supports time-domain offset and / or the supported time-domain offset range by sending the time-frequency position of Msg1. Or, the terminal device can indicate whether it supports time-domain offset and / or the supported time-domain offset range through the random sequence corresponding to Msg1.

[0033] When Msg1 indicates that the terminal device only supports time-domain offset, the reader can configure the time-domain offset for the terminal device from a predefined time-domain offset range. When Msg1 indicates that the terminal device does not support time-domain offset, the corresponding Msg3 reuses the time-domain configuration of Msg1.

[0034] In conjunction with the first aspect, in certain implementations of the first aspect, the time-domain offset range includes: multiple time-domain offsets, or time-domain offset range groups, or the maximum value of the time-domain offset. Thus, the first message can indicate the time-domain offset range supported by the reporting terminal device, for example, reporting multiple time-domain offsets supported by the terminal device, or reporting time-domain offset range groups supported by the terminal device, or reporting the maximum value of the time-domain offset supported by the terminal device. Correspondingly, the reader determines the time-domain offset range supported by the terminal device, the time-domain offset indicated by the second message does not exceed the range reported by Msg1, and the time-domain offset range of the third message sent by the terminal device does not exceed the reported capability range.

[0035] Optionally, in some implementations of the first aspect, Msg1 may report the frequency range supported by the terminal device.

[0036] In conjunction with the first aspect, in some implementations of the first aspect, the start indicator or clock acquisition portion of the second message indicates whether the terminal device performs a time domain offset.

[0037] In conjunction with the first aspect, in some implementations of the first aspect, when the start indicator or clock acquisition part of the second message instructs the terminal device to perform a time domain offset, the message content of the second message can indicate the time domain offset amount.

[0038] In conjunction with the first aspect, in some implementations of the first aspect, when the start indicator or clock acquisition part of the second message instructs the terminal device to perform a time domain offset, and the message content of the second message does not indicate the time domain offset, the corresponding time domain offset of the terminal device is a predefined value.

[0039] In this way, after receiving the second message, the terminal device can determine whether to perform a time-domain offset based on the start indicator or the clock acquisition section. If a time-domain offset is performed, the terminal device can obtain the time-domain offset from the message content of the second message. If the message content of the second message does not indicate a time-domain offset, the terminal device can perform a time-domain offset based on a predefined value.

[0040] In conjunction with the first aspect, in some implementations of the first aspect, the duration of the high and low levels corresponding to the start indicator of the second message indicates whether the terminal device performs a time-domain offset.

[0041] In conjunction with the first aspect, in some implementations of the first aspect, whether the total duration of the high level and the total duration of the low level corresponding to the start indicator of the second message are the same indicates whether the terminal device should perform a time-domain offset; or, whether the duration of the high level and the duration of the low level of the i-th level segment corresponding to the start indicator of the second message are the same indicates whether the terminal device should perform a time-domain offset, where i is an integer ≥ 1. For example, when the total duration of the high level and the total duration of the low level of the start indicator are the same, it indicates that no time-domain offset should be performed; when the total duration of the high level and the total duration of the low level are different, it indicates that a time-domain offset should be performed. For example, when the duration of the high level and the low level of the i-th level segment are the same, it indicates that no time-domain offset should be performed; when the duration of the high level and the low level of the i-th level segment are different, it indicates that a time-domain offset should be performed. After receiving the second message, the terminal device determines whether to perform a time-domain offset based on the duration of the high level and the low level.

[0042] In conjunction with the first aspect, in some implementations of the first aspect, the M value corresponding to the clock acquisition portion of the second message indicates whether the terminal device should perform a time-domain offset. The duration of the clock acquisition portion varies with the M value; for example, the duration shortens as the M value increases. Different M values ​​are predefined to correspond to either not performing a time-domain offset or indicating that a time-domain offset should be performed. For example, when the M value is large, it indicates that the A-IoT device should not perform a time-domain offset; when the M value is small, it indicates that the A-IoT device should perform a time-domain offset. The network device can instruct the terminal device whether to perform a time-domain offset based on the magnitude of the M value. Correspondingly, the terminal device can determine whether to perform a time-domain offset based on the magnitude of the M value.

[0043] Alternatively, the M-value and repetition factor corresponding to the clock acquisition section of the second message indicate whether the terminal device should perform a time-domain offset. There can be multiple combinations of the M-value and repetition factor, and different combinations of the M-value and repetition factor may indicate that the A-IoT device should not perform a time-domain offset, or that it should perform a time-domain offset.

[0044] In conjunction with the first aspect, in some implementations of the first aspect, the M value corresponding to the clock acquisition portion of the second message instructing the terminal device to perform time-domain offset includes: the M value corresponding to the clock acquisition portion of the second message instructing the time-domain offset range grouping; or, the M value corresponding to the clock acquisition portion of the second message and the repetition factor instructing the terminal device to perform time-domain offset includes: the M value corresponding to the clock acquisition portion of the second message and the repetition factor instructing the time-domain offset range grouping.

[0045] In conjunction with the first aspect, in some implementations of the first aspect, when the message content of the second message includes multiple time-domain offsets, the multiple time-domain offsets are sorted according to a random identifier.

[0046] In conjunction with the first aspect, in some implementations of the first aspect, the start indicator or clock acquisition portion of the second message indicates the time domain offset. Accordingly, the message content of the second message may not carry the time domain offset.

[0047] In conjunction with the first aspect, in some implementations of the first aspect, the information carried by the message content of the third message is associated with the time slot length and the guard interval length.

[0048] The information carried in Msg3 can be divided into multiple sets of options, including mandatory options and multiple optional options. Different combinations of time slot length / guard interval length are associated with each optional option, and each combination of time slot length and guard interval length corresponds to a set of mandatory and optional options. The A-IoT device can determine the mandatory and optional options of message 3 based on the time slot length and guard interval length indicated by Msg2.

[0049] Secondly, embodiments of this application provide a communication method applied to a terminal device in an environmental Internet of Things (IoT) system. The terminal device can be an A-IoT device. In this method, the terminal device sends a first message, which reports whether the terminal device supports frequency offset and / or the supported frequency offset range. The frequency offset is an offset relative to the location of the frequency domain resources carrying the first message. The terminal device receives a second message, which indicates whether the terminal device performs frequency offset and / or the amount of frequency offset, and / or indicates time domain resources, which are different from the time domain resources carrying the first message. The terminal device can send a third message according to the indication of the second message. If the second message indicates that the terminal device performs frequency offset and indicates time domain resources, the third message is carried on the time-frequency resources determined based on the second message. If the second message does not indicate that the terminal device performs frequency offset and / or time domain resources, the third message is carried using the frequency domain resources and / or time domain resources carrying the first message.

[0050] The aforementioned first, second, and third messages are used for one uplink synchronization of the terminal device. The first message can be Msg1 in the four-step random access process, the second message can be Msg2 in the four-step random access process, and the third message can be Msg3 in the four-step random access process. The terminal device reports frequency offset capability through Msg1, and the reader / writer uses Msg2 to indicate whether there is frequency offset, the frequency offset value, time domain resources, or one or more other information to configure the frequency domain resources and / or time domain resources of Msg3, thereby achieving flexible configuration of Msg3. Since the time domain and frequency domain resources allocated by the base station to multiple A-IoT devices in the A-IoT scenario are limited, the method provided in this application embodiment allows the reader / writer to utilize the time domain and frequency domain resources more efficiently and reasonably by flexibly configuring the frequency domain and time domain resources of Msg3, completing the process of multiple A-IoT devices accessing the reader / writer.

[0051] Due to the complex operating environment of IoT systems, and the fact that A-IoT devices are simple, low-cost hardware communication devices, they are prone to mutual interference when transmitting Msg3. The method provided in this application involves the reader instructing the A-IoT device to perform a frequency shift via Msg2. When transmitting Msg3, the A-IoT device can perform a certain frequency shift. By appropriately shifting the frequency, the spectrum is fully utilized, and the Msg3 transmitted by different A-IoT devices are as far apart as possible in the frequency domain, avoiding mutual interference, reducing the impact of interference on the reader's signal quality, and facilitating the demodulation of Msg3 by the reader.

[0052] In conjunction with the second aspect, in some implementations of the second aspect, the message content of the first message, or the time-frequency position of the first message, or the random sequence corresponding to the first message, indicates whether the terminal device supports frequency offset and / or the supported frequency offset range. Thus, the terminal device can indicate whether it supports frequency offset and / or the supported frequency offset range through the message content of Msg1. For example, the message content may include a first field, the value of which can indicate whether the A-IoT device supports frequency offset. Alternatively, the terminal device can indicate whether it supports frequency offset and / or the supported frequency offset range by sending the time-frequency position of Msg1. Or, the terminal device can indicate whether it supports frequency offset and / or the supported frequency offset range through the random sequence corresponding to Msg1.

[0053] When Msg1 indicates that the terminal device only supports frequency offset, the reader can configure the frequency offset for the terminal device from a predefined frequency offset range. When Msg1 indicates that the terminal device does not support frequency offset, the corresponding Msg3 reuses the frequency domain configuration of Msg1.

[0054] In conjunction with the second aspect, in some implementations of the second aspect, the frequency offset range includes: multiple frequency offsets, frequency offset range groups, or the maximum value of the frequency offset. Thus, the first message can indicate the frequency offset range supported by the reporting terminal device, for example, reporting multiple frequency offsets supported by the terminal device, or reporting frequency offset range groups supported by the terminal device, or reporting the maximum value of the frequency offset supported by the terminal device. Accordingly, the reader determines the frequency offset range supported by the terminal device, the frequency offset indicated by the second message does not exceed the range reported by Msg1, and the frequency offset range sent by the terminal device in the third message does not exceed the reported capability range.

[0055] Optionally, in some implementations of the second aspect, Msg1 may report the frequency range supported by the terminal device.

[0056] In conjunction with the second aspect, in some implementations of the second aspect, the start indicator or clock acquisition portion of the second message indicates whether the terminal device performs a frequency offset.

[0057] In conjunction with the second aspect, in some implementations of the second aspect, when the start indicator or clock acquisition part of the second message instructs the terminal device to perform a frequency offset, the message content of the second message can indicate the frequency offset amount.

[0058] In conjunction with the second aspect, in some implementations of the second aspect, when the start indicator or clock acquisition part of the second message instructs the terminal device to perform a frequency offset, and the message content of the second message does not indicate the frequency offset, the frequency offset corresponding to the terminal device is a predefined value.

[0059] In this way, after receiving the second message, the terminal device can determine whether to perform a frequency offset based on the start indicator or the clock acquisition section. If a frequency offset is performed, the terminal device can obtain the frequency offset amount from the message content of the second message. If the message content of the second message does not indicate a frequency offset amount, the terminal device can perform a frequency offset based on a predefined value.

[0060] In conjunction with the second aspect, in some implementations of the second aspect, the duration of the high and low levels corresponding to the start indicator of the second message indicates whether the terminal device performs a frequency shift.

[0061] In conjunction with the second aspect, in some implementations of the second aspect, whether the total duration of the high level and the total duration of the low level corresponding to the start indicator of the second message are the same indicates whether the terminal device should perform frequency shifting; or, whether the duration of the high level and the duration of the low level of the i-th level segment corresponding to the start indicator of the second message are the same indicates whether the terminal device should perform frequency shifting, where i is an integer ≥ 1. For example, when the total duration of the high level and the total duration of the low level of the start indicator are the same, it indicates that no frequency shifting should be performed; when the total duration of the high level and the total duration of the low level are different, it indicates that frequency shifting should be performed. For example, when the duration of the high level and the low level of the i-th level segment are the same, it indicates that no frequency shifting should be performed; when the duration of the high level and the low level of the i-th level segment are different, it indicates that frequency shifting should be performed. After receiving the second message, the terminal device determines whether to perform frequency shifting based on the duration of the high level and the low level.

[0062] In conjunction with the second aspect, in some implementations of the second aspect, the M value corresponding to the clock acquisition portion of the second message indicates whether the terminal device should perform a frequency shift. The duration of the clock acquisition portion varies with the M value; for example, the duration shortens as the M value increases. Different M values ​​are predefined to correspond to either not performing a frequency shift or performing a frequency shift. For example, a large M value indicates that the A-IoT device should not perform a frequency shift; a small M value indicates that the A-IoT device should perform a frequency shift. The network device can instruct the terminal device whether to perform a frequency shift based on the magnitude of the M value. Correspondingly, the terminal device can determine whether to perform a frequency shift based on the magnitude of the M value.

[0063] Alternatively, the M-value and repetition factor corresponding to the clock acquisition section of the second message indicate whether the terminal device should perform frequency offset. There can be multiple combinations of M-value and repetition factor, and different combinations of M-value and repetition factor may indicate that the A-IoT device should not perform frequency offset, or that the A-IoT device should perform frequency offset.

[0064] In conjunction with the second aspect, in some implementations of the second aspect, the M value corresponding to the clock acquisition part of the second message instructing the terminal device to perform frequency offset includes: the M value corresponding to the clock acquisition part of the second message instructing the frequency offset range grouping; or, the M value corresponding to the clock acquisition part of the second message and the repetition factor instructing the terminal device to perform frequency offset includes: the M value corresponding to the clock acquisition part of the second message and the repetition factor instructing the frequency offset range grouping.

[0065] In conjunction with the second aspect, in some implementations of the second aspect, when the message content of the second message includes multiple frequency offsets, the multiple frequency offsets are ordered according to a random identifier.

[0066] When the reader receives a Msg1 and replies with a Msg2, the reader can provide different instructions for different A-IoT devices. For example, for A-IoT device 1, the frequency offset is indicated by the aforementioned start indicator or clock acquisition section of Msg2, and the message content of Msg2 indicates the corresponding frequency offset amount for A-IoT device 1. For A-IoT device 2, no frequency offset is indicated by the aforementioned start indicator or clock acquisition section.

[0067] When the reader receives multiple Msg1 responses along with a single Msg2, it broadcasts a Msg2 message to multiple A-IoT devices. The start indicator or clock acquisition portion of Msg2 uniformly instructs the multiple A-IoT devices whether to perform frequency offset. The message content of Msg2 indicates the frequency offset for each A-IoT device, and these offsets can be ordered according to the random IDs of the A-IoT devices. Correspondingly, the terminal device can determine its own frequency offset based on its own random identifier.

[0068] In conjunction with the second aspect, in some implementations of the second aspect, the start indicator or clock acquisition portion of the second message indicates the frequency offset. Accordingly, the message content of the second message may not carry the frequency offset.

[0069] In conjunction with the second aspect, in some implementations of the second aspect, the frequency offset includes one of the following: the frequency offset value, the identifier of the frequency offset value, and the coefficient of the frequency offset, wherein the coefficient is an integer multiple of the minimum chip length corresponding to the message encoding method.

[0070] In conjunction with the second aspect, in some implementations of the second aspect, the time-domain resources include at least one of the following: the time slot length and guard interval length occupied by the Msg3 resource, the time-domain start time, and the time-domain end time. The time slot length is the duration for transmitting valid data. The guard interval length is the time interval between two Msg3 time intervals received by the base station, used to avoid inter-symbol interference. The time slot length and the guard interval length support multiple different values.

[0071] When indicating time-domain resources, network devices can specify the time slot length, time-domain start time, and time-domain end time of Msg3 in the second message. Alternatively, they can specify the time slot length and time-domain start time of Msg3 in the second message. After receiving Msg2, the terminal device can determine its own time-domain resources based on the indications in Msg2. By reconfiguring time-domain resources, Msg3 can occupy a longer time-domain resource length to carry more information and reduce time-domain resource waste; it can also reduce interference by increasing the length of the guard interval.

[0072] Optionally, the time-domain start time can also be represented by the start time slot position, and the time-domain end time can be represented by the end time slot position. The start time slot position and / or end time slot position of the time-domain resource indicated by Msg2 can be a value based on a reference position, such as the clock start position, the end / start position of the start indicator, the end position of the clock acquisition section, etc.

[0073] The start and / or end timeslot positions of the time-domain resources indicated by Msg2 can also be relative values ​​to the resource timeslot positions of Msg1. The network device and the terminal device know the value of each Msg1 resource timeslot position relative to a reference position (denoted as value 1). Msg2 indicates the relative value of the resource timeslot position of Msg3 relative to the resource timeslot position of Msg1 (denoted as value 2). The terminal device can determine the resource timeslot position of Msg3 based on value 1 and value 2. For example, if the resource of Msg1 is the third resource in time-domain order, after receiving the indication of Msg2, the terminal device can calculate the corresponding resource position of Msg3 as the first resource in time-domain order by using value 2.

[0074] Optionally, in some implementations, the second message may indicate whether the terminal device performs a time-domain offset and / or a time-domain offset amount. A time-domain offset is an offset from the time-domain resource location where the message sent by the terminal device is located. Time-domain resources can be represented by REs or time slots.

[0075] In conjunction with the second aspect, in some implementations of the second aspect, the message content of the first message, or the time-frequency position of the first message, or the random sequence corresponding to the first message, indicates whether the terminal device supports time-domain offset and / or the supported time-domain offset range. Thus, the terminal device can indicate whether it supports time-domain offset and / or the supported time-domain offset range through the message content of Msg1. For example, the message content may include a first field, the value of which can indicate whether the A-IoT device supports time-domain offset. Alternatively, the terminal device can indicate whether it supports time-domain offset and / or the supported time-domain offset range by sending the time-frequency position of Msg1. Or, the terminal device can indicate whether it supports time-domain offset and / or the supported time-domain offset range through the random sequence corresponding to Msg1.

[0076] When Msg1 indicates that the terminal device only supports time-domain offset, the reader can configure the time-domain offset for the terminal device from a predefined time-domain offset range. When Msg1 indicates that the terminal device does not support time-domain offset, the corresponding Msg3 reuses the time-domain configuration of Msg1.

[0077] In conjunction with the second aspect, in some implementations of the second aspect, the time-domain offset range includes: multiple time-domain offsets, or time-domain offset range groups, or the maximum value of the time-domain offset. Thus, the first message can indicate the time-domain offset range supported by the reporting terminal device, for example, reporting multiple time-domain offsets supported by the terminal device, or reporting time-domain offset range groups supported by the terminal device, or reporting the maximum value of the time-domain offset supported by the terminal device. Accordingly, the reader determines the time-domain offset range supported by the terminal device, the time-domain offset indicated by the second message does not exceed the range reported by Msg1, and the time-domain offset range of the third message sent by the terminal device does not exceed the reported capability range.

[0078] Optionally, in some implementations of the second aspect, Msg1 may report the frequency range supported by the terminal device.

[0079] In conjunction with the second aspect, in some implementations of the second aspect, the start indicator or clock acquisition portion of the second message indicates whether the terminal device performs a time domain offset.

[0080] In conjunction with the second aspect, in some implementations of the second aspect, when the start indicator or clock acquisition part of the second message instructs the terminal device to perform a time domain offset, the message content of the second message can indicate the time domain offset amount.

[0081] In conjunction with the second aspect, in some implementations of the second aspect, when the start indicator or clock acquisition part of the second message instructs the terminal device to perform a time domain offset, and the message content of the second message does not indicate the time domain offset, the corresponding time domain offset of the terminal device is a predefined value.

[0082] In this way, after receiving the second message, the terminal device can determine whether to perform a time-domain offset based on the start indicator or the clock acquisition section. If a time-domain offset is performed, the terminal device can obtain the time-domain offset from the message content of the second message. If the message content of the second message does not indicate a time-domain offset, the terminal device can perform a time-domain offset based on a predefined value.

[0083] In conjunction with the second aspect, in some implementations of the second aspect, the duration of the high and low levels corresponding to the start indicator of the second message indicates whether the terminal device performs a time-domain offset.

[0084] In conjunction with the second aspect, in some implementations of the second aspect, whether the total duration of the high level and the total duration of the low level corresponding to the start indicator of the second message are the same indicates whether the terminal device should perform a time-domain offset; or, whether the duration of the high level and the duration of the low level of the i-th level segment corresponding to the start indicator of the second message are the same indicates whether the terminal device should perform a time-domain offset, where i is an integer ≥ 1. For example, when the total duration of the high level and the total duration of the low level of the start indicator are the same, it indicates that no time-domain offset should be performed; when the total duration of the high level and the total duration of the low level are different, it indicates that a time-domain offset should be performed. For example, when the duration of the high level and the low level of the i-th level segment are the same, it indicates that no time-domain offset should be performed; when the duration of the high level and the low level of the i-th level segment are different, it indicates that a time-domain offset should be performed. After receiving the second message, the terminal device determines whether to perform a time-domain offset based on the duration of the high level and the low level.

[0085] In conjunction with the second aspect, in some implementations of the second aspect, the M value corresponding to the clock acquisition portion of the second message indicates whether the terminal device should perform a time-domain offset. The duration of the clock acquisition portion varies with the M value; for example, the duration shortens as the M value increases. Different M values ​​are predefined to correspond to either not performing a time-domain offset or indicating that a time-domain offset should be performed. For example, when the M value is large, it indicates that the A-IoT device should not perform a time-domain offset; when the M value is small, it indicates that the A-IoT device should perform a time-domain offset. The network device can instruct the terminal device whether to perform a time-domain offset based on the magnitude of the M value. Correspondingly, the terminal device can determine whether to perform a time-domain offset based on the magnitude of the M value.

[0086] Alternatively, the M-value and repetition factor corresponding to the clock acquisition section of the second message indicate whether the terminal device should perform a time-domain offset. There can be multiple combinations of the M-value and repetition factor, and different combinations of the M-value and repetition factor may indicate that the A-IoT device should not perform a time-domain offset, or that it should perform a time-domain offset.

[0087] In conjunction with the second aspect, in some implementations of the second aspect, the M value corresponding to the clock acquisition portion of the second message instructing the terminal device to perform time-domain offset includes: the M value corresponding to the clock acquisition portion of the second message instructing the time-domain offset range grouping; or, the M value corresponding to the clock acquisition portion of the second message and the repetition factor instructing the terminal device to perform time-domain offset includes: the M value corresponding to the clock acquisition portion of the second message and the repetition factor instructing the time-domain offset range grouping.

[0088] In conjunction with the second aspect, in some implementations of the second aspect, when the message content of the second message includes multiple time-domain offsets, the multiple time-domain offsets are sorted according to a random identifier.

[0089] In conjunction with the second aspect, in some implementations of the second aspect, the start indicator or clock acquisition portion of the second message indicates the time domain offset. Accordingly, the message content of the second message may not carry the time domain offset.

[0090] In conjunction with the second aspect, in some implementations of the second aspect, the information carried by the message content of the third message is associated with the time slot length and the guard interval length.

[0091] The information carried in Msg3 can be divided into multiple sets of options, including mandatory options and multiple optional options. Different combinations of time slot length / guard interval length are associated with each optional option, and each combination of time slot length and guard interval length corresponds to a set of mandatory and optional options. The A-IoT device can determine the mandatory and optional options of message 3 based on the time slot length and guard interval length indicated by Msg2.

[0092] Thirdly, a communication apparatus is provided, comprising units for performing steps of the method as described in any implementation of the first aspect, or comprising units for performing steps of the method as described in any implementation of the second aspect.

[0093] Fourthly, a communication device is provided, including a processor and an interface, the interface being used to send and / or receive signals, such that the processor performs the method described in any of the implementations of any of the preceding aspects.

[0094] Fifthly, a communication device is provided, comprising: a processor coupled to a memory for storing programs or instructions, wherein when the program or instructions are executed by the processor, the communication device performs the method described in any of the above-mentioned implementations.

[0095] In a sixth aspect, a communication system is provided, which includes the network equipment as described in the first aspect above and the terminal equipment as described in the second aspect above.

[0096] In a seventh aspect, a computer-readable medium is provided for storing a computer program that, when run on a computer, causes the computer to perform the method described in any of the implementations of any of the preceding aspects.

[0097] Eighthly, a chip is provided, on which a processing circuit (or processor) is disposed, the processing circuit (or processor) being used to execute the method in any of the above-mentioned implementations.

[0098] Ninthly, a computer program product comprising instructions is provided, the computer program product including: a computer program (also referred to as code or instructions), which, when run, causes a computer to perform a method in any of the implementations of any of the above aspects. Attached Figure Description

[0099] Figure 1 shows a schematic diagram of the structure of a communication system provided in an embodiment of this application;

[0100] Figure 2 shows a frequency offset schematic diagram provided in an embodiment of this application;

[0101] Figure 3 shows a flowchart of a communication method provided in an embodiment of this application;

[0102] Figure 4 shows a schematic diagram of a time-domain resource configuration provided in an embodiment of this application;

[0103] Figure 5 is a schematic diagram of the structure of a communication device provided in an embodiment of this application;

[0104] Figure 6 is a schematic diagram of another communication device provided in an embodiment of this application. Detailed Implementation

[0105] The technical solutions in the embodiments of this application will now be described with reference to the accompanying drawings. The network architecture and business scenarios described in the embodiments of this application are for the purpose of more clearly illustrating the technical solutions of the embodiments of this application, and do not constitute a limitation on the technical solutions provided in the embodiments of this application. As those skilled in the art will know, with the evolution of network architecture and the emergence of new business scenarios, the technical solutions provided in the embodiments of this application are also applicable to similar technical problems.

[0106] In this application, ordinal numbers such as "1", "2", "3", "first", "second", "third", and "fourth" are used to distinguish multiple objects and are not used to limit the order of multiple objects. "Multiple" in this application refers to two or more. The term "and / or" in this application is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, and B existing alone. Additionally, the character " / " in this document generally indicates that the preceding and following related objects have an "or" relationship. The term "at least one" in this application can represent "one" and "two or more". For example, at least one of A, B, and C can represent: A existing alone, B existing alone, C existing alone, A and B existing simultaneously, A and C existing simultaneously, C and B existing simultaneously, and A, B, and C existing simultaneously. In this application, "instruction" can include both direct and indirect instruction. For example, when describing information that indicates information I, the information can directly indicate I or indirectly indicate I, but does not necessarily indicate that the information carries I.

[0107] The technical solutions provided in this application can be applied to various communication systems, such as Long Term Evolution (LTE) systems, 5th Generation (5G) mobile communication systems, and New Radio (NR). The 5G mobile communication systems in this application include non-standalone (NSA) 5G mobile communication systems and standalone (SA) 5G mobile communication systems. The technical solutions provided in this application can also be applied to future communication systems, such as 6th Generation (6G) and 7th Generation (7G) mobile communication systems. The technical solutions provided in this application can also be applied to device-to-device (D2D) communication, vehicle-to-everything (V2X) communication, machine-to-machine (M2M) communication, machine-type communication (MTC), and Internet of Things (IoT) communication systems (e.g., Ambient Internet of Things (A-IoT) communication systems), or other communication systems. This application does not limit these applications.

[0108] For example, Figure 1 is a schematic diagram of a communication system provided in an embodiment of this application. As shown in Figure 1, the communication system includes network devices (110a and 110b in Figure 1) and terminal devices (120a-120g in Figure 1). The network device is an entity on the network side used to transmit or receive signals and communicate with the terminal devices; it also exchanges received air frames with Internet Protocol (IP) packets, acting as a router between the terminal devices and the rest of the access network, which may include an IP network, etc.

[0109] Network devices can also be devices that enable terminal devices to connect to a wireless network, such as radio access network (RAN) devices. RAN devices are sometimes also referred to as access network devices, RAN entities, or access nodes. For example, network devices can be base stations, 5G base stations (Next-Generation node B, gNB), new radio controllers (NR controllers), evolved Node Bs (eNodeBs), radio network controllers (RNCs), node Bs (NBs), base station controllers (BSCs), base transceiver stations (BTSs), home base stations (e.g., home evolved Node Bs, or home node Bs (HNBs)), base band units (BBUs), access points (APs), wireless relay nodes, wireless backhaul nodes, transmission points (TPs), or transmission and reception points (TRPs / TPs) or remote radio heads (RRHs) in Wi-Fi systems. Alternatively, the RAN node can also be a radio unit (RU), a centralized unit (CU), a distributed unit (DU), a CU control plane (CU-CP) node, or a CU user plane (CU-UP) node. The embodiments of this application do not limit the specific technology or device form used in the wireless access network equipment. In this application, access network equipment is referred to as network equipment; unless otherwise specified, network equipment refers to access network equipment in this application.

[0110] A terminal device is a device with wireless transceiver capabilities. Terminal devices can also be called terminals, access terminals, user terminals, user equipment (UE), mobile stations (MS), mobile terminals (MT), wireless terminals, wireless communication devices, etc. Terminal devices can be mobile phones, tablets, laptops, PDAs, mobile internet devices (MID), wearable devices, in-vehicle terminal devices, virtual reality (VR) devices, augmented reality (AR) devices, wireless terminals in industrial control, wireless terminals in self-driving cars, wireless terminals in smart grids, wireless terminals in transportation safety, wireless terminals in smart cities, or wireless terminals in smart homes, etc. This application does not limit the specific technology or device form used in the terminal embodiments.

[0111] Terminal devices can also be Internet of Things (IoT) terminal devices, such as smart tags, industrial control components, smart home devices, and environmental IoT devices (A-IoT devices). Among them, A-IoT devices can be battery-free devices without energy storage or devices with limited energy storage. A-IoT devices can be powered by energy harvesting (such as solar energy, radio waves, motion, vibration, heat, pressure, or other power sources).

[0112] Access network devices and / or terminals can be fixed or mobile. They can be deployed on land, including indoors or outdoors, handheld or vehicle-mounted; on water; or in the air on aircraft, balloons, and satellites. This application does not limit the application scenarios of the access network devices and terminals. Access network devices and terminal devices can be deployed in the same or different scenarios; for example, both can be deployed on land; or the access network device can be deployed on land, and the terminal device on water, etc., and so on.

[0113] In the embodiments of this application, the communication device with access network device function can be an access network device, or a module (such as a chip, chip system, or software module) in the access network device, or a control subsystem containing access network device function. For example, a control subsystem containing access network device function can be a control center in scenarios where terminals can be applied, such as smart grids, industrial control, intelligent transportation, or smart cities.

[0114] In the embodiments of this application, a communication device with terminal functionality may be a terminal, a module within a terminal (such as a chip, chip system, modem, or software model), or a device that includes terminal functionality. The following description uses the example of an access network device for implementing the functions of an access network device and a terminal device for implementing the functions of a terminal device.

[0115] For ease of explanation, in this embodiment, an environmental IoT device is used as an example of a terminal device, and a base station is used as an example of a network device.

[0116] In the A-IoT (Artificial Intelligence of Things) scenario, the base station can provide a reader function, triggering a Random Access (RA) procedure. This procedure is used for A-IoT devices to access the network for data transmission. The RA procedure can be either Contention-Based Random Access (CBRA) or Contention-Free Random Access (CFRA), depending on the reader configuration. The method described in this application can be applied to either CBRA or CFRA. The RA procedure can be a two-step or four-step random access procedure. The four-step random access procedure in the A-IoT scenario is described below.

[0117] During the four-step random access process, the A-IoT device and the reader can exchange four messages (Msg): Message 1 (Msg1), Message 2 (Msg2), Message 3 (Msg3), and Message 4 (Msg4). Msg2 and Msg4 represent reader-to-device (R2D) transmissions. Msg1 and Msg3 represent device-to-reader (D2R) transmissions, requiring uplink scheduling resources. Configuring the time and frequency domain resources for Msg3 is a problem that needs to be solved.

[0118] This application provides a communication method in which A-IoT devices report frequency offset capabilities via Msg1, and the reader configures the frequency domain resources and / or time domain resources of Msg3 by indicating one or more time-frequency resource-related information via Msg2, thereby achieving flexible configuration of the time-frequency resources of Msg3. Since the time-domain and frequency domain resources allocated by the base station to multiple A-IoT devices in an A-IoT scenario are limited, the method provided in this application allows the reader to utilize the time-domain and frequency domain resources more efficiently and rationally by flexibly configuring the frequency-domain and time-domain resources of Msg3, completing the process of multiple A-IoT devices accessing the reader.

[0119] To facilitate understanding of the technical solutions of the embodiments of this application, some terms involved in the embodiments of this application will be briefly explained below.

[0120] 1. Frequency Offset: The offset of the message sent by the terminal device relative to the frequency domain resource location where Msg 1 is located. Frequency domain resources can be represented by resource elements (REs), subcarriers, chip length, or number of chips.

[0121] In this embodiment, the frequency domain resource location corresponding to Msg1 is used as a reference to indicate whether the frequency domain resource location corresponding to Msg3 needs to be moved. "Frequency domain resource location corresponding to Msg1" refers to the frequency domain resource location used by the A-IoT device when transmitting Msg1. "Frequency domain resource location corresponding to Msg3" refers to the frequency domain resource location used by the A-IoT device when transmitting Msg3.

[0122] For example, Figure 2 illustrates a frequency offset diagram provided in an embodiment of this application. A-IoT device 1 sends its corresponding Msg1 in frequency domain resource 1, A-IoT device 2 sends its corresponding Msg1 in frequency domain resource 1, A-IoT device 3 sends its corresponding Msg1 in frequency domain resource 3, and A-IoT device 4 sends its corresponding Msg1 in frequency domain resource 4. Due to resource conflicts and interference, the Msg1 messages corresponding to A-IoT device 1 and A-IoT device 2 are not successfully sent to the reader. After receiving the Msg1 messages corresponding to A-IoT device 3 and A-IoT device 4, the reader reconfigures frequency domain resource 1 to frequency domain resource 4, thus reconfiguring the frequency domain resources for A-IoT device 3 and A-IoT device 4. The Msg2 instruction indicates the frequency domain resource locations for A-IoT devices 3 and 4. For example, it instructs A-IoT device 3 to perform a frequency offset, while instructing A-IoT device 4 not to perform a frequency offset. This allows A-IoT device 3 to transmit the corresponding Msg3 using frequency domain resource 1, and A-IoT device 4 to transmit the corresponding Msg3 using frequency domain resource 4. This fully utilizes the spectrum and increases the frequency domain spacing between the corresponding Msg3 messages of A-IoT devices 3 and 4.

[0123] Due to the complex operating environment of IoT systems, A-IoT devices are prone to mutual interference when sending Msg3. The method provided in this application allows the reader to indicate the frequency domain resource location of A-IoT devices via Msg2, for example, whether the A-IoT devices are frequency-shifted. When A-IoT devices send Msg3, they can make a certain frequency shift, fully utilizing the spectrum. Simultaneously, it ensures that the Msg3 sent by different A-IoT devices are as far apart as possible in the frequency domain, avoiding mutual interference. Furthermore, it reduces the impact of interference on the reader's signal quality, which is beneficial for the reader's demodulation of Msg3.

[0124] It is understandable that frequency offset has a certain range. The allowed frequency offset range for A-IoT devices can be predefined, and this range is determined based on the actual situation. For example, using RE as the offset unit, the allowed frequency offset range can be [-24, 24], [-3, 3], [-4, 4], or [-8, 8], etc. Taking the allowed frequency offset range of [-4, 4] as an example, the allowed frequency offset values ​​can be -4, -3, -2, -1, 0, 1, 2, 3, 4. Taking the allowed frequency offset range of [-8, 8] as an example, the allowed frequency offset values ​​can be -8, -7, -6, -5, -4, -3, -2, -1, 0, 1, 2, 3, 4, 5, 6, 7, 8. For example, a frequency offset value of 1RE indicates that the frequency domain resource location corresponding to Msg3 is N0+1, and N0 is the frequency domain resource location corresponding to Msg1. The frequency offset range supported by the A-IoT device is within the allowed range. It should be understood that A-IoT devices also report their frequency offset capabilities through this step, and subsequent instructions from the reader cannot exceed the reported capability range.

[0125] 2. Start-indicator: Located in the preamble of the R2D transmission message, it is used to identify the start of the R2D transmission.

[0126] Base stations can use a specific sequence as a start indicator, employing ON / OFF mode, i.e., high / low level transmission. In the relevant description of the start indicator section in 3GPP TS 38.769, the ON / OFF mode falling into the final Rel-19 version has two possibilities: single ON-OFF transmission and multi-ON-OFF transmission. A single ON-OFF transmission consists of one high-level transmission and one low-level transmission, where ON and OFF may have the same or different durations. Multi-ON-OFF transmission consists of multiple high-voltage transmissions and low-voltage transmissions, where different ON and different OFF signals can have the same or different durations, and different parts can have the same or different durations.

[0127] 3. Clock Acquisition: Located in the preamble portion of the R2D transmission message and after the start indicator portion, it is used by A-IoT devices to determine the duration of the binary on-off keying (OOK) chip for subsequent physical R2D channel (PRDCH) transmission.

[0128] In the description of the clock acquisition section in 3GPP TS 38.769, the clock acquisition section is based on OOK modulation technology for encoding. The OOK modulation technology can be OOK-4. OOK-4 modulation uses one OFDM symbol to transmit M bits / chips, where M is an integer greater than 1.

[0129] In some implementations, the duration of the clock acquisition section varies with different values ​​of M; for example, the duration decreases as the value of M increases. In other implementations, the duration of the clock acquisition section remains constant based on different values ​​of M for repetition; that is, the repetition factor increases as the value of M increases to keep the duration constant.

[0130] The technical solution of this application will be described in detail below with reference to Figures 3 and 4, using specific method embodiments.

[0131] For example, Figure 3 is a flowchart of a communication method provided in an embodiment of this application. It can be understood that the terminal device in Figure 3 can be the terminal device in Figure 1 (e.g., terminal device 120), or it can refer to a device within the terminal device (e.g., a processor, chip, or chip system). The access network device can be the access network device 110 in Figure 1, or it can refer to a device within the access network device (e.g., a processor, chip, or chip system).

[0132] It is also understood that some or all of the information exchanged between the terminal device and the access network device in Figure 3 can be carried in existing messages, channels, signals, or signaling, or can be newly defined messages, channels, signals, or signaling, without specific limitations. Referring to Figure 3, the communication method may specifically include the following steps S301-S303.

[0133] S301, the A-IoT device sends a first message to the reader. Correspondingly, the reader receives the first message. The reader can be a base station.

[0134] The first message can be a random access request message, such as Msg1 in the random access process. Msg1 can include a preamble and message content. The message content of Msg1 can include a payload, such as a random number (RN) identifier (ID) generated by the A-IoT device. The message content can sometimes also be referred to as control information.

[0135] Before the A-IoT device sends Msg1, the reader sends an R2D message, such as message 0 (Msg0), to the A-IoT device. This R2D message triggers random access. The R2D message includes the random access configuration for transmitting Msg1, such as the frequency division multiple access (FDMA) resource location / index. Accordingly, the A-IoT device receives this R2D message and obtains the random access configuration. The A-IoT device can then randomly select a time-frequency resource from those provided / allocated by the reader to send Msg1.

[0136] It is understandable that one reader can communicate with multiple A-IoT devices, and one reader can receive Msg1 from multiple A-IoT devices.

[0137] In this embodiment, Msg1 is used to report the frequency offset capability of the A-IoT device itself. Msg1 can indicate whether the A-IoT device sending the message supports frequency offset and / or the supported frequency offset range. If Msg1 indicates that the terminal device supports frequency offset, the reader can configure time-frequency resources for transmitting Msg3 for the terminal device. If Msg1 indicates that the terminal device does not support frequency offset, the terminal device uses the time-frequency resources corresponding to Msg1 to send Msg3.

[0138] A-IoT devices can provide specific instructions by sending the time-frequency location of Msg1, the random sequence corresponding to Msg1, and the message content of Msg1. An example is given below.

[0139] In some implementations, message 1 (Msg1) can indicate whether the A-IoT device supports frequency offset.

[0140] For example, the message content of message 1 may include a first field, the value of which can indicate whether the A-IoT device supports frequency offset. For example, the value of the first field can be 0 or 1. When the value of the first field is 0, it indicates that the A-IoT device does not support frequency offset; when the value of the first field is 1, it indicates that the A-IoT device supports frequency offset.

[0141] For example, whether the message content of message 1 includes the first field can indicate whether the A-IoT device supports frequency offset. For instance, when the message content of message 1 includes the first field, it indicates that the A-IoT device supports frequency offset; when the message content of message 1 does not include the first field, it indicates that the A-IoT device does not support frequency offset.

[0142] For example, the time-frequency location corresponding to message 1 indicates whether the A-IoT device supports frequency offset. For instance, a base station can allocate multiple time-frequency locations for the A-IoT device, and the A-IoT device selects one of these locations to send Msg1. One or more of the predefined time-frequency locations (e.g., time-frequency location 1) correspond to A-IoT devices supporting frequency offset, while the remaining locations (e.g., time-frequency location 2) correspond to A-IoT devices not supporting frequency offset. When the A-IoT device selects time-frequency location 1 to send message 1, it indicates that the A-IoT device supports frequency offset. When the A-IoT device selects time-frequency location 2 to send message 1, it indicates that the A-IoT device does not support frequency offset.

[0143] For example, the random sequence corresponding to message 1 indicates whether the A-IoT device supports frequency offset. For instance, a base station can assign multiple random sequences to the A-IoT device, and the A-IoT device selects one of these random sequences to generate a random ID. One or more of the predefined random sequences (e.g., random sequence 1) correspond to the A-IoT device supporting frequency offset, while the remaining random sequences (e.g., random sequence 2) correspond to the A-IoT device not supporting frequency offset. When message 1 corresponds to random sequence 1, it indicates that the A-IoT device supports frequency offset; when message 1 corresponds to random sequence 2, it indicates that the A-IoT device does not support frequency offset.

[0144] Based on the above implementation, the first message can indicate whether the terminal device supports frequency offset. Accordingly, when Msg1 indicates that the A-IoT device supports frequency offset, the reader can configure a frequency offset for the A-IoT device from a predefined frequency offset range. The frequency offset can be represented by a frequency offset value, a frequency offset value identifier, a frequency offset coefficient, etc.

[0145] In some implementations, Msg1 can indicate multiple frequency offsets supported by the A-IoT device.

[0146] For example, Msg1 can carry multiple supported frequency offsets. For instance, using frequency offset values ​​to represent frequency offsets, the control information portion of Msg1 can carry multiple supported frequency offset values. For example, if the A-IoT device supports multiple frequency offset values ​​{1,2,3,4}, Msg1 carries the information {1,2,3,4}. Alternatively, if the A-IoT device supports multiple frequency offset values ​​{1,2,3,4,5,6,7,8}, Msg1 carries the information {1,2,3,4,5,6,7,8}. Accordingly, after receiving message 1, the reader parses the information {1,2,3,4,5,6,7,8} from message 1 and can determine the multiple frequency offset values ​​supported by the A-IoT device.

[0147] For example, the random sequence corresponding to message 1 indicates multiple frequency offset values ​​supported by the A-IoT device. For instance, multiple frequency offset values ​​are predefined for each random sequence. For example, the multiple frequency offset values ​​corresponding to random sequence 1 are {1,2,3,4}, and the multiple frequency offset values ​​corresponding to random sequence 2 are {5,6,7,8}. When message 1 corresponds to random sequence 1, it indicates that the multiple frequency offset values ​​supported by the A-IoT device are {1,2,3,4}; when message 1 corresponds to random sequence 2, it indicates that the multiple frequency offset values ​​supported by the A-IoT device are {5,6,7,8}.

[0148] For example, the time-frequency location corresponding to message 1 indicates multiple frequency offset values ​​supported by the A-IoT device. For instance, multiple frequency offset values ​​are predefined for each time-frequency location; for example, the multiple frequency offset values ​​corresponding to time-frequency location 1 are {1,2,3,4}, and the multiple frequency offset values ​​corresponding to time-frequency location 2 are {5,6,7,8}. When message 1 includes time-frequency location 1, it indicates that the multiple frequency offset values ​​supported by the A-IoT device are {1,2,3,4}. When the message includes time-frequency location 2, it indicates that the multiple frequency offset values ​​supported by the A-IoT device are {5,6,7,8}.

[0149] In some other implementations, Msg1 can indicate the frequency offset range grouping supported by the A-IoT device.

[0150] For example, frequency offset values ​​are pre-grouped, with each group corresponding to an identifier. A first mapping relationship can be stored in the reader and the A-IoT device, including the correspondence between frequency offset range groups and identifiers. The control information portion of Msg1 can carry the identifier corresponding to the supported frequency offset range group, which indicates the frequency offset range supported by the A-IoT device. Accordingly, after receiving message 1, the reader parses the identifier from it to determine the frequency offset range group supported by the A-IoT device.

[0151] For example, when the allowed frequency offset range is [1,4], the frequency offset values ​​can be grouped, with {1,2} as the first group and {3,4} as the second group. Each group is assigned an identifier; for example, the identifier for {1,2} could be group1, and the identifier for {3,4} could be group2. Alternatively, the identifier for {1,2} could be 00, and the identifier for {3,4} could be 01. In one example, when the frequency offset range supported by the A-IoT device is {1,2}, Msg1 could carry the identifier 00.

[0152] For example, the random sequence corresponding to message 1 indicates the frequency offset range grouping supported by the A-IoT device. The frequency offset range grouping corresponding to each random sequence is predefined. For example, random sequence 1 corresponds to frequency offset range grouping {1,2}. Random sequence 2 corresponds to frequency offset range grouping {3,4}; when message 1 corresponds to random sequence 1, it indicates that the A-IoT device supports frequency offset range grouping {1,2}; when message 1 corresponds to random sequence 2, it indicates that the A-IoT device supports frequency offset range grouping {3,4}.

[0153] For example, the time-frequency location corresponding to message 1 indicates the frequency offset range grouping supported by the A-IoT device. Each time-frequency location corresponds to a predefined frequency offset range grouping. For instance, time-frequency location 1 corresponds to frequency offset range grouping {1,2}, and time-frequency location 2 corresponds to frequency offset range grouping {3,4}. When the A-IoT device selects time-frequency location 1 to send message 1, it indicates that the A-IoT device supports frequency offset range grouping {1,2}; when the A-IoT device selects time-frequency location 2 to send message 1, it indicates that the A-IoT device supports frequency offset range grouping {3,4}.

[0154] In some implementations, Msg1 can indicate the maximum frequency offset supported by the A-IoT device.

[0155] For example, the control information section of Msg1 may carry the maximum frequency offset supported by the A-IoT device. For instance, if the frequency offset values ​​supported by the A-IoT device are -3, -2, -1, 0, 1, 2, and 3, then the maximum frequency offset supported by the A-IoT device is the absolute value 3. The A-IoT device may carry the maximum supported frequency offset as -3 and / or 3 in the control information section of Msg1.

[0156] In other implementations, Msg1 can indicate that the A-IoT device supports frequency offsets and specify multiple frequency offsets supported by the A-IoT device. For example, the message content portion of Msg1 carries a first field and the multiple supported frequency offsets. For example, the time-frequency position corresponding to Msg1 indicates that the A-IoT device supports frequency offsets, and the message content portion of Msg1 carries the multiple supported frequency offsets. For example, the random sequence corresponding to Msg1 indicates that the A-IoT device supports frequency offsets, and the message content portion of Msg1 carries the multiple supported frequency offsets.

[0157] In other implementations, Msg1 can indicate that the A-IoT device supports frequency offset and specify the supported frequency offset range groupings. For example, the message content portion of Msg1 carries a first field and an identifier of the supported frequency offset range groupings. For example, the time-frequency position corresponding to Msg1 indicates that the A-IoT device supports frequency offset, and the message content portion of Msg1 carries an identifier of the supported frequency offset range groupings. For example, the random sequence corresponding to Msg1 indicates that the A-IoT device supports frequency offset, and the message content portion of Msg1 carries an identifier of the supported frequency offset range groupings.

[0158] In other implementations, Msg1 can indicate that the A-IoT device supports frequency offset and also indicate the maximum supported frequency offset range. For example, the message content portion of Msg1 carries a first field and the maximum supported frequency offset range. For example, the time-frequency position corresponding to Msg1 indicates that the A-IoT device supports frequency offset, and the message content portion of Msg1 carries the maximum supported frequency offset range. For example, the random sequence corresponding to Msg1 indicates that the A-IoT device supports frequency offset, and the message content portion of Msg1 carries the maximum supported frequency offset range.

[0159] Based on the above implementation, the first message can indicate the frequency offset range supported by the reporting terminal device. For example, it can report multiple frequency offsets supported by the terminal device, or report a group of frequency offset ranges supported by the terminal device, or report the maximum frequency offset supported by the terminal device. Accordingly, the reader determines the frequency offset range supported by the terminal device. The frequency offset indicated by message 2 does not exceed the range reported by Msg1, and the frequency offset range sent by the A-IoT device in message 3 does not exceed the reported capability range.

[0160] Optionally, in some embodiments, Msg1 may report the frequency range supported by the A-IoT device.

[0161] S302, the reader sends a second message to the A-IoT device. Correspondingly, the A-IoT device receives the second message.

[0162] The second message can be a random access response, for example, it can be Msg2 in the random access process.

[0163] After receiving Msg1, the reader replies with Msg2 to the A-IoT device. The reader can reply with one Msg2 for each received Msg1, or it can reply with one Msg2 for multiple received Msg1s. Msg2 includes a preamble and the message content. The preamble may include a start indicator and a clock acquisition section, etc.

[0164] In this embodiment, the reader configures frequency domain resources and / or time domain resources corresponding to each Msg3, and sends them to the A-IoT device through Msg2.

[0165] For frequency domain resource configuration, in some implementations, Msg2 can indicate whether the A-IoT device should perform a frequency offset and / or the amount of the offset. Specifically, if a frequency offset is performed, the preamble of Msg2 indicates that the A-IoT device should perform a frequency offset, and the amount of the offset is indicated in the message content; alternatively, the preamble of Msg2 indicates the amount of the frequency offset; or, the preamble of Msg2 indicates that the A-IoT device should perform a frequency offset, but the amount of the offset is not indicated in the message content. A detailed explanation with examples follows.

[0166] In some implementations, the Msg2 start-indicator indicates whether the A-IoT device is performing a frequency offset.

[0167] Optionally, the sequence corresponding to the start indicator of Msg2 indicates whether the A-IoT device performs a frequency offset.

[0168] The start indicator supports the use of one or more different sequences, with each sequence predefined to indicate whether frequency offset should be performed. For example, when the start indicator is sequence 1 (e.g., sequence 1 is 0101), it indicates that the A-IoT device should not perform frequency offset; when the start indicator is sequence 2 (e.g., sequence 2 is 1001), it indicates that the A-IoT device should perform frequency offset.

[0169] Optionally, the duration of the high (ON) and low (OFF) levels corresponding to the start indicator of Msg2 indicates whether the A-IoT device is performing a frequency shift.

[0170] For example, whether the total duration of the high level and the total duration of the low level corresponding to the start indicator are the same indicates whether the A-IoT device should perform frequency shifting. For instance, when the total duration of the high level and the total duration of the low level of the start indicator are the same, it indicates no frequency shifting; when the total duration of the high level and the total duration of the low level are different, it indicates frequency shifting. For example, if the start-indicator is 111000, the total duration of the high level is 3 chips, and the total duration of the low level is 3 chips, the total duration of the high and low levels is the same, indicating no frequency shifting. For example, if the start-indicator is 100001, the total duration of the high level is 2 chips, and the total duration of the low level is 4 chips, the total duration of the high and low levels is different, indicating frequency shifting.

[0171] For example, in a multi-segment on / off transmission mode, the start indicator can correspond to multiple ON / OFF level segments. Whether the duration of the high level and the duration of the low level in the i-th level segment are the same indicates whether the A-IoT device should perform frequency shifting. For instance, if the duration of the high level and the duration of the low level in the i-th level segment are the same, it indicates that no frequency shifting should occur; if the duration of the high level and the duration of the low level in the i-th level segment are different, it indicates that frequency shifting should occur. Here, i is an integer ≥ 1.

[0172] For example, the value of 'i' can be 1. When the duration of the first high-level and the first low-level segments corresponding to the start indicator are the same, no frequency shift is indicated; when the durations of the first high-level and the first low-level segments are different, a frequency shift is indicated. For example, if the start-indicator is 110010, where the first high-level segment lasts for 2 chips and the first low-level segment lasts for 2 chips, and the durations of the first high-level and low-level segments are the same, no frequency shift is indicated. Alternatively, if the start-indicator is 100010, where the first high-level segment lasts for 1 chip and the first low-level segment lasts for 3 chips, and the durations of the first high-level and low-level segments are different, a frequency shift is indicated.

[0173] For example, the value of 'i' can be 3. When the durations of the third high-level and third low-level segments corresponding to the start indicator are the same, no frequency shift is indicated; when the durations of the third high-level and third low-level segments are different, a frequency shift is indicated. For example, if the start-indicator is 10101100, where the third high-level segment lasts for 2 chips and the third low-level segment lasts for 2 chips, and the durations of the third high-level and low-level segments are the same, no frequency shift is indicated. Alternatively, if the start-indicator is 10101110, where the third high-level segment lasts for 3 chips and the third low-level segment lasts for 1 chip, and the durations of the third high-level and low-level segments are different, a frequency shift is indicated.

[0174] In some implementations, the clock-acquisition portion of Msg2 indicates whether the A-IoT device is performing a frequency shift.

[0175] Optionally, the M value corresponding to the clock acquisition section of Msg2 indicates whether the A-IoT device performs frequency offset.

[0176] Different predefined M values ​​correspond to either no frequency offset or a frequency offset instruction. For example, a larger M value instructs the A-IoT device not to perform a frequency offset, while a smaller M value instructs the A-IoT device to perform a frequency offset. The value of M can be 2, 4, 6, 8, etc. In this embodiment, the definition of the M value is not limited; for example, M > 8 is considered a large M value, and M ≤ 8 is considered a small M value. In this implementation, the duration of the clock acquisition section is not fixed; for example, as the M value increases, the duration shortens.

[0177] Optionally, when using the M value to instruct A-IoT devices to perform frequency offset, the M value can indicate frequency offset range grouping. That is, when the M value indicates whether the A-IoT device should perform frequency offset, different M values ​​correspond to either no frequency offset or grouped frequency offset ranges. For example, if the frequency offset range is divided into two groups: {1,2} and {3,4}, when the M value is 2, it indicates that the A-IoT device should not perform frequency offset; when the M value is 4, it indicates that the frequency offset range is group 1 {1,2}; and when the M value is 6, it indicates that the frequency offset range is group 2 {3,4}. In this implementation, the duration of the clock acquisition section is not fixed.

[0178] Optionally, the M value and repetition factor corresponding to the clock acquisition section of Msg2 indicate whether the A-IoT device performs frequency offset.

[0179] Different combinations of the M value and the repetition factor indicate either that the A-IoT device should not perform frequency offset, or that it should perform frequency offset. There can be various combinations of the M value and the repetition factor, such as M=2 and repetition factor=2, M=4 and repetition factor=4, M=6 and repetition factor=6, M=12 and repetition factor=12, and so on. One or more combinations can indicate frequency offset; other combinations can indicate no frequency offset. For example, a smaller M value indicates no frequency offset, while a larger M value indicates frequency offset. In this implementation, the duration of the clock acquisition is fixed; the repetition factor increases as the M value increases to maintain a constant duration.

[0180] Optionally, when using the M-value and repetition factor to instruct A-IoT devices to perform frequency offset, the M-value and repetition factor can indicate frequency offset range grouping. That is, different combinations of the M-value and repetition factor correspond to either instructing the A-IoT device not to perform frequency offset, or instructing frequency offset range grouping. For example, if the frequency offset range is divided into two groups: {1,2} and {3,4}, when the M-value is 2 and the repetition factor is 2, the A-IoT device is instructed not to perform frequency offset; when the M-value is 4 and the repetition factor is 4, the range indicating frequency offset is group 1 {1,2}; and when the M-value is 6 and the repetition factor is 6, the range indicating frequency offset is group 2 {3,4}. In this implementation, the duration of the clock acquisition section is fixed.

[0181] Based on the above implementation, the start indicator or clock acquisition part of Msg2 indicates whether the A-IoT device should perform a frequency offset. Here, "indicating whether the A-IoT device should perform an offset" can also be expressed as "indicating whether the message content part indicates the frequency offset amount".

[0182] If the preamble of Msg2 indicates a frequency offset, the message content of Msg2 may indicate the frequency offset amount. The frequency offset amount includes one of the following: the frequency offset value, an identifier for the frequency offset value, and a frequency offset coefficient.

[0183] Optionally, the message content of Msg2 can carry a frequency offset value, such as 0RE, 2RE, or 4RE.

[0184] Optionally, the Msg2 message content can carry an identifier for the frequency offset value. For example, the identifier for the frequency offset value can be a mapped value of the frequency offset value. A predefined correspondence between frequency offset values ​​and mapped values ​​is stored by the reader and the A-IoT device. For example, 2RE corresponds to a mapped value of 1, 4RE corresponds to a mapped value of 2, and 6RE corresponds to a mapped value of 3. The Msg2 message content can carry the mapped value corresponding to the frequency offset value, such as 1, 2, 3, etc., and the A-IoT device can parse the frequency offset value from the mapped value.

[0185] For example, the identifier of the frequency offset value can be the order of the frequency offset value within the frequency offset range group. For instance, the clock-acquisition portion of Msg2 indicates the frequency offset range group, where the first frequency offset value in the group is represented by binary 00, and the second by binary 01. For example, if the frequency offset range group is {1,2}, and the reader assigns a frequency offset value of 1RE to the A-IoT device, the message content of Msg2 can carry the identifier "00" for the frequency offset value. This saves bits in the message content.

[0186] Optionally, the Msg2 message content can carry a frequency offset coefficient n, where the coefficient n is an integer multiple of the minimum chip length corresponding to the message encoding method. Different encoding methods correspond to different minimum chip lengths. For example, in Manchester encoding, the frequency offset value is expressed as n*1 / (2*chip_length). For a square wave, the frequency offset value is expressed as n*R / Tb. After receiving the Msg2 message, the A-IoT device parses the coefficient n and can then determine the frequency offset value.

[0187] It should be noted that when the reader responds with a Msg2 for each Msg1 received, the reader can provide different instructions for different A-IoT devices. For example, for A-IoT device 1, the frequency offset is indicated by the start indicator or clock acquisition section of Msg2, and the message content of Msg2 indicates the corresponding frequency offset amount for A-IoT device 1, such as 2RE. For A-IoT device 2, no frequency offset is indicated by the start indicator or clock acquisition section, and the message content of Msg2 does not indicate the frequency offset amount for A-IoT device 2. For A-IoT device 3, the frequency offset is indicated by the start indicator or clock acquisition section of Msg2, and the message content of Msg2 indicates the corresponding frequency offset amount for A-IoT device 3, such as 4RE.

[0188] When the reader receives multiple Msg1 responses along with a single Msg2, it broadcasts a Msg2 message to multiple A-IoT devices. The start indicator or clock acquisition portion of Msg2 uniformly instructs the multiple A-IoT devices whether to perform a frequency offset. The message content of Msg2 indicates the frequency offset for each A-IoT device. After receiving Msg2, each A-IoT device parses its own corresponding frequency offset.

[0189] Multiple frequency offsets in the Msg2 message content can be sorted according to the random IDs corresponding to the A-IoT devices. For example, if the frequency offset value for A-IoT device 1 is 2RE, for A-IoT device 2 it is 4RE, and for A-IoT device 3 it is 6RE, then the message content would be: 2RE, 4RE, 6RE. As another example, if the frequency offset value for A-IoT device 1 is 4RE, for A-IoT device 2 it is 6RE, and for A-IoT device 3 it is 2RE, then the message content would be: 2, 1, 3.

[0190] In some cases, if the A-IoT device supports frequency offset, the preamble of Msg2 indicates frequency offset, but the message content of Msg2 does not indicate the amount of frequency offset. After receiving Msg2, the A-IoT device can use a default value as the frequency offset value; for example, the default frequency offset value can be 0. This application does not limit the value of the default value. It should be noted that different A-IoT devices may have different default frequency offset values.

[0191] If the A-IoT device supports frequency offset, the preamble of Msg2 indicates that frequency offset is not performed, the message content of Msg2 does not include the indication field, and the corresponding Msg3 reuses the FDMA resource index of Msg1.

[0192] If the A-IoT device does not have frequency offset capability, the preamble of Msg2 does not need to indicate the frequency offset, the message content of Msg2 does not include the indication field, and the corresponding Msg3 reuses the FDMA resource index of Msg1.

[0193] In some other implementations, when the reader replies with a Msg2 for each Msg1 received, the start indicator or clock acquisition part of Msg2 can indicate the frequency offset.

[0194] Optionally, the start indicator of Msg2 corresponds to the sequence indicator frequency offset.

[0195] For example, a frequency offset value is predefined for each sequence. For instance, sequence 1 corresponds to a frequency offset value of 1RE, sequence 2 corresponds to a frequency offset value of 2RE, and sequence 3 corresponds to a frequency offset value of 3RE. For example, when the sequence corresponding to the start indicator of Msg2 is sequence 1, the frequency offset value corresponding to the A-IoT device is 1RE.

[0196] For example, a frequency offset coefficient is predefined for each sequence. For instance, sequence 1 corresponds to a frequency offset coefficient n1, sequence 2 corresponds to a frequency offset coefficient n2, and sequence 3 corresponds to a frequency offset coefficient n3. For example, when the sequence corresponding to the start indicator of Msg2 is sequence 1, the frequency offset coefficient corresponding to the A-IoT device is n1.

[0197] Optionally, the M value corresponding to the clock acquisition section of Msg2 indicates the frequency offset.

[0198] For example, a frequency offset value is predefined for each M value. For instance, an M value of 2 corresponds to a frequency offset value of 1RE; an M value of 4 corresponds to a frequency offset value of 2RE; and an M value of 6 corresponds to a frequency offset value of 3RE. For example, when the M value corresponding to the clock acquisition part of Msg2 is 4, it indicates that the frequency offset value corresponding to the A-IoT device is 2RE.

[0199] For example, a frequency offset coefficient is predefined for each M value. For instance, an M value of 2 corresponds to a frequency offset coefficient n1, an M value of 4 corresponds to a frequency offset coefficient n2, and an M value of 6 corresponds to a frequency offset coefficient n3. For example, when the M value corresponding to the clock acquisition part of Msg2 is 4, the frequency offset coefficient corresponding to the A-IoT device is n2.

[0200] Optionally, the M-value and repetition factor corresponding to the clock acquisition section of Msg2 indicate the frequency offset.

[0201] For example, a frequency offset value corresponding to a predefined combination of M value and repetition factor is defined. For instance, an M value of 2 and a repetition factor of 2 correspond to a frequency offset value of 1RE; an M value of 4 and a repetition factor of 4 correspond to a frequency offset value of 2RE; and an M value of 6 and a repetition factor of 6 correspond to a frequency offset value of 3RE. For example, when the M value of the clock acquisition part of Msg2 is 4 and the repetition factor is 4, the frequency offset value corresponding to the A-IoT device is 2RE.

[0202] For example, a frequency offset coefficient corresponding to a predefined combination of M value and repetition factor is defined. For instance, an M value of 2 and a repetition factor of 2 correspond to a frequency offset coefficient n1; an M value of 4 and a repetition factor of 4 correspond to a frequency offset coefficient n2; and an M value of 6 and a repetition factor of 6 correspond to a frequency offset coefficient n3. For example, when the M value corresponding to the clock acquisition part of Msg2 is 4, the frequency offset coefficient corresponding to the A-IoT device is n2.

[0203] When the frequency offset is directly indicated in the start indicator or clock acquisition section of Msg2, the message content section of Msg2 does not need to indicate the frequency offset.

[0204] In some implementations, Msg2 can indicate the frequency domain resource location of A-IoT devices for frequency domain resource configuration. For example, Msg2 can indicate the subcarrier location corresponding to each A-IoT device.

[0205] Specifically, based on the frequency offset capabilities already reported by the A-IoT device, the Reader selects a specific frequency offset value from the A-IoT device's offset range and indicates it to the A-IoT device via Msg2. The A-IoT device then uses this frequency offset value, combined with the frequency domain resource location of Msg1, to determine the location of the frequency domain resource configuration for Msg3. For example, if the starting position of the frequency domain for Msg1 of the A-IoT device is relative to CRB0 + 10RB, and the indicated frequency offset value is 2RB, then the starting position of the frequency domain for Msg3 is relative to CRB0 + 12RB.

[0206] For time-domain resources, Msg2 can indicate the required time-domain resource length and / or time-domain start time for each A-IoT device's corresponding Msg3. The time-domain resource length (size) includes: the slot length and / or guard interval length occupied by each Msg3 resource. The slot length is the duration for transmitting valid data. The guard interval length is the time interval between two Msg3 receptions by the base station, used to avoid inter-symbol interference.

[0207] In one implementation, Msg2 can indicate the time slot length, time domain start time, and time domain end time of the Msg3 corresponding to the A-IoT device.

[0208] Optionally, the time-domain start and end times can be determined based on the clock start time, in units of chips or slots. For example, the time-domain start time is the time window starting from the x-th chip from the clock start time. The time-domain end time is the time window starting from the y-th chip from the clock start time. x and y are both positive integers greater than or equal to 1. The time window has a predefined length.

[0209] Optionally, the time-domain start time can also be represented by the start time slot position, and the time-domain end time can be represented by the end time slot position. The start time slot position and / or end time slot position of the time-domain resource indicated by Msg2 can be a value based on a reference position, such as the clock start position, the end / start position of the start indicator, the end position of the clock acquisition section, etc.

[0210] The start and / or end timeslot positions of the time-domain resources indicated by Msg2 can also be relative values ​​to the resource timeslot positions of Msg1. The network device and the terminal device know the value of each Msg1 resource timeslot position relative to a reference position (denoted as value 1). Msg2 indicates the relative value of the resource timeslot position of Msg3 relative to the resource timeslot position of Msg1 (denoted as value 2). The terminal device can determine the resource timeslot position of Msg3 based on value 1 and value 2. For example, if the resource of Msg1 is the third resource in time-domain order, after receiving the indication of Msg2, the terminal device can calculate the corresponding resource position of Msg3 as the first resource in time-domain order by using value 2.

[0211] If Msg2 is a one-to-one response to Msg1, Msg2 indicates the slot length, time domain start time, and time domain end time of the corresponding A-IoT device. For example, the message content is: slot, guard, time domain start time, time domain end time. For example, the time domain start time can be 5 chips, and the time domain end time can be 15 chips.

[0212] If Msg2 is a one-to-many response to Msg1, Msg2 indicates the slot length, time domain start time, and time domain end time of multiple A-IoT devices. For example, the message content is: slot, guard, start time 1, end time 1, start time 2, end time 2, start time 3, end time 3. The message content of Msg2 arranges the time domain sequence of each A-IoT device in a specific order, for example, according to their RN IDs.

[0213] In another implementation, Msg2 can indicate the time slot length and time domain start time of the Msg3 corresponding to the A-IoT device.

[0214] If Msg2 is a one-to-one response to Msg1, Msg2 indicates the slot length and time domain start time of the corresponding A-IoT device. For example, the message content is: slot, guard, time domain start time.

[0215] If Msg2 is a one-to-many response to Msg1, Msg2 indicates the slot length and time domain start time of multiple A-IoT devices. For example, the message content is: slot, guard, start time 1, start time 2, start time 3.

[0216] In another implementation, Msg2 can indicate the time slot length and time domain end time of the Msg3 corresponding to the A-IoT device.

[0217] If Msg2 is a one-to-one response to Msg1, Msg2 indicates the slot length and time domain end time of the corresponding A-IoT device. For example, the message content is: slot, guard, time domain end time.

[0218] If Msg2 is a one-to-many response to Msg1, Msg2 indicates the slot length and time domain end time of multiple A-IoT devices. For example, the message content is: slot, guard, end time 1, end time 2, end time 3.

[0219] In another implementation, Msg2 can indicate the time-domain start time and time-domain end time of Msg3 corresponding to the A-IoT device.

[0220] If Msg2 is a one-to-one response to Msg1, Msg2 indicates the time-domain start and end times of the corresponding A-IoT device. For example, the message content is: start time, end time.

[0221] If Msg2 is a one-to-one response to Msg1, Msg2 indicates the time-domain start and end times of multiple A-IoT devices. For example, the message content is: start time 1, end time 1, start time 2, end time 2, start time 3, end time 3.

[0222] After receiving Msg2, the A-IoT device can determine its own time-domain resources based on the instructions in Msg2. In this embodiment, the time slot length and the guard interval length support multiple different values. The specific values ​​of the time slot length and the guard interval length can be determined according to specific circumstances, and this embodiment does not limit them.

[0223] For example, Figure 4(a) illustrates a time-domain resource configuration diagram. A-IoT device 1 sends its corresponding Msg1 in time slot 1, A-IoT device 2 sends its corresponding Msg1 in time slot 2, A-IoT device 3 sends its corresponding Msg1 in time slot 3, and A-IoT device 4 sends its corresponding Msg1 in time slot 4. Due to signal interference or other reasons, the Msg1 messages corresponding to A-IoT devices 1 and 2 are not successfully sent to the reader. After receiving the Msg1 messages corresponding to A-IoT devices 3 and 4, the reader reconfigures time slots 1 through 4, reconfiguring the time-domain resources for A-IoT devices 3 and 4. It then indicates the time-domain resource locations of A-IoT devices 3 and 4 via Msg2. At this point, the time domain resources indicated by Msg2 are different from those corresponding to Msg1. A-IoT device 3 can use time slots 1 and 2 to send Msg3, and A-IoT device 4 can use time slots 3 and 4 to send Msg3. Therefore, Msg3 can occupy more time domain resources to carry more information and reduce time domain resource waste. Interference can also be reduced by increasing the length of the guard interval.

[0224] Figure 4(b) illustrates another temporal resource configuration, where Msg1 corresponding to A-IoT device 2 is not successfully sent to the reader. After receiving Msg1 from A-IoT devices 1, 3, and 4, the reader reconfigures time slots 1 to 4, reconfiguring the temporal resources for A-IoT devices 1, 3, and 4. In this case, three Msg3s are sent in time slots 1 to 4, allowing Msg3 to occupy a larger portion of the temporal resource length.

[0225] In this embodiment, the time-domain resources of Msg3 are configured using one or more of the following information: time slot resource length, guard interval length, time-domain start time, and time-domain end time. This allows for flexible configuration of the time-domain resources of Msg3. Furthermore, Msg3s sent by different A-IoT devices can only be further apart in the time domain, avoiding mutual interference, reducing the impact of interference on the reader signal quality, and facilitating the demodulation of Msg3 by the reader.

[0226] For time-domain resource configuration, in some implementations, Msg2 can instruct the A-IoT device whether to perform a time-domain offset and / or the amount of the offset. A time-domain offset is the deviation of a message sent by the terminal device relative to the time-domain resource location where Msg1 is situated. Time-domain resources can be represented by REs or time slots. The following explanation uses REs as an example.

[0227] Specifically, for the case of time-domain offset, the preamble sequence of Msg2 instructs the A-IoT device to perform a time-domain offset, and the amount of the time-domain offset is indicated in the message content; alternatively, the preamble sequence of Msg2 indicates the amount of the time-domain offset; or alternatively, the preamble sequence of Msg2 instructs the A-IoT device to perform a time-domain offset, but the amount of the time-domain offset is not indicated in the message content. A detailed explanation with examples follows.

[0228] In some implementations, the Msg2 start-indicator indicates whether the A-IoT device is performing a time-domain offset.

[0229] Optionally, the sequence corresponding to the start indicator of Msg2 indicates whether the A-IoT device is entering the time domain offset.

[0230] The start indicator supports the use of one or more different sequences, with each sequence predefined to indicate whether a time-domain offset is performed. For example, when the start indicator is sequence 1 (e.g., sequence 1 is 0101), it indicates that the A-IoT device does not perform a time-domain offset; when the start indicator is sequence 2 (e.g., sequence 2 is 1001), it indicates that the A-IoT device performs a time-domain offset.

[0231] Optionally, the duration of the high (ON) and low (OFF) levels corresponding to the start indicator of Msg2 indicates whether the A-IoT device is performing a time-domain offset.

[0232] For example, whether the total duration of the high level and the total duration of the low level corresponding to the start indicator are the same indicates whether the A-IoT device should perform a time-domain offset. For instance, when the total duration of the high level and the total duration of the low level of the start indicator are the same, it indicates that no time-domain offset is performed; when the total duration of the high level and the total duration of the low level are different, it indicates that a time-domain offset is performed. For example, if the start-indicator is 111000, the total duration of the high level is 3 chips, and the total duration of the low level is 3 chips, the total duration of the high level and the low level are the same, indicating that no time-domain offset is performed. For example, if the start-indicator is 100001, the total duration of the high level is 2 chips, and the total duration of the low level is 4 chips, the total duration of the high level and the low level are different, indicating that a time-domain offset is performed.

[0233] For example, in a multi-segment on / off transmission mode, the start indicator can correspond to multiple ON / OFF level segments. Whether the duration of the high level and the duration of the low level in the i-th level segment are the same indicates whether the A-IoT device should perform a time-domain offset. For instance, if the durations of the high and low levels in the i-th level segment are the same, it indicates no time-domain offset; if the durations of the high and low levels in the i-th level segment are different, it indicates a time-domain offset. Here, i is an integer ≥ 1.

[0234] For example, the value of 'i' can be 1. When the duration of the first high-level and the first low-level corresponding to the start indicator are the same, no time-domain offset is indicated; when the durations of the first high-level and the first low-level are different, a time-domain offset is indicated. For example, if the start-indicator is 110010, where the first high-level lasts for 2 chips and the first low-level lasts for 2 chips, and the durations of the first high-level and the low-level are the same, no time-domain offset is indicated. Alternatively, if the start-indicator is 100010, where the first high-level lasts for 1 chip and the first low-level lasts for 3 chips, and the durations of the first high-level and the low-level are different, a time-domain offset is indicated.

[0235] For example, the value of 'i' can be 3. When the durations of the third high-level and third low-level segments corresponding to the start indicator are the same, no time-domain offset is indicated; when the durations of the third high-level and third low-level segments are different, a time-domain offset is indicated. For example, if the start-indicator is 10101100, where the third high-level segment lasts for 2 chips and the third low-level segment lasts for 2 chips, and the durations of the third high-level and low-level segments are the same, no time-domain offset is indicated. Alternatively, if the start-indicator is 10101110, where the third high-level segment lasts for 3 chips and the third low-level segment lasts for 1 chip, and the durations of the third high-level and low-level segments are different, a time-domain offset is indicated.

[0236] In some other implementations, the clock-acquisition portion of Msg2 indicates whether the A-IoT device is performing a time-domain offset.

[0237] Optionally, the M value corresponding to the clock acquisition section of Msg2 indicates whether the A-IoT device performs a time domain offset.

[0238] Different predefined M values ​​correspond to either no time-domain offset or an indication of time-domain offset. For example, a larger M value indicates that the A-IoT device should not perform a time-domain offset; a smaller M value indicates that the A-IoT device should perform a time-domain offset. The value of M can be 2, 4, 6, 8, etc. In this embodiment, the definition of the magnitude of the M value is not limited; for example, M > 8 is considered a large M value, and M ≤ 8 is considered a small M value.

[0239] Optionally, when using the M value to indicate whether an A-IoT device should perform a time-domain offset, the M value can indicate a grouping of time-domain offset ranges. That is, when the M value indicates whether an A-IoT device should perform a time-domain offset, different M values ​​correspond to either no time-domain offset or a grouping of time-domain offset ranges. For example, if the time-domain offset range is divided into two groups: {1,2} and {3,4}, when the M value is 2, it indicates that the A-IoT device should not perform a time-domain offset; when the M value is 4, it indicates that the range for time-domain offset is group 1 {1,2}; and when the M value is 6, it indicates that the range for time-domain offset is group 2 {3,4}.

[0240] Optionally, the M value and repetition factor corresponding to the clock acquisition section of Msg2 indicate whether the A-IoT device performs time-domain offset.

[0241] Different combinations of the M-value and the repetition factor indicate whether the A-IoT device should not perform a time-domain offset or should perform one. There can be various combinations of the M-value and the repetition factor, such as M=2 and a repetition factor of 2, M=4 and a repetition factor of 4, M=6 and a repetition factor of 6, M=12 and a repetition factor of 12, and so on. One or more combinations can indicate a time-domain offset; other combinations can indicate that no time-domain offset should be performed. For example, a smaller M-value indicates no time-domain offset, while a larger M-value indicates a time-domain offset.

[0242] Optionally, when using the M-value and repetition factor to instruct A-IoT devices to perform time-domain offsets, the M-value and repetition factor can indicate time-domain offset range groupings. That is, different combinations of the M-value and repetition factor correspond to either instructing the A-IoT device not to perform a time-domain offset, or instructing time-domain offset range groupings. For example, if the time-domain offset range is divided into two groups: {1,2} and {3,4}, when the M-value is 2 and the repetition factor is 2, it indicates that the A-IoT device does not perform a time-domain offset; when the M-value is 4 and the repetition factor is 4, it indicates that the range for time-domain offset is group 1 {1,2}; and when the M-value is 6 and the repetition factor is 6, it indicates that the range for time-domain offset is group 2 {3,4}.

[0243] Based on the above implementation, the start indicator or clock acquisition part of Msg2 indicates whether the A-IoT device performs a time domain offset. Here, "indicating whether the A-IoT device performs an offset" can also be expressed as "indicating whether the message content part indicates the time domain offset amount".

[0244] If the preamble of Msg2 indicates a time-domain offset, the message content of Msg2 can indicate the time-domain offset. The time-domain offset includes one of the following: the time-domain offset value, an identifier for the time-domain offset value, and a time-domain offset coefficient.

[0245] Optionally, the message content of Msg2 can carry a time-domain offset value, such as 0RE, 2RE, or 4RE.

[0246] Optionally, the Msg2 message content can carry an identifier for the time-domain offset value. For example, the identifier for the time-domain offset value can be a mapped value of the time-domain offset value. A predefined correspondence between time-domain offset values ​​and mapped values ​​is stored by the reader / writer and the A-IoT device. For example, 2RE corresponds to a mapped value of 1, 4RE corresponds to a mapped value of 2, and 6RE corresponds to a mapped value of 3. The Msg2 message content can carry the mapped value corresponding to the time-domain offset value, such as 1, 2, 3, etc., and the A-IoT device can parse the time-domain offset value from the mapped value.

[0247] For example, the identifier of the time-domain offset value can be the order of the time-domain offset value within the time-domain offset range group. For instance, the clock acquisition section of Msg2 indicates the time-domain offset range group, where the first time-domain offset value in the group is represented by binary 00, and the second-ranked time-domain offset value is represented by binary 01. For example, if the time-domain offset range group is {1,2}, and the reader assigns a time-domain offset value of 1RE to the A-IoT device, the message content of Msg2 can carry the identifier "00" for the time-domain offset value. This saves bits in the message content.

[0248] Optionally, the message content of Msg2 can carry a time-domain offset coefficient m.

[0249] For example, the coefficient m can be an integer multiple of one time slot. For instance, the message content of Msg2 can carry a time domain offset coefficient m of 1, indicating that Msg3 is offset by m*1 time slots relative to Msg1. After receiving Msg2, the A-IoT device parses the coefficient m and can then determine the time domain offset value.

[0250] It should be noted that when the reader responds with a Msg2 for each Msg1 received, the reader can provide different instructions for different A-IoT devices. For example, for A-IoT device 1, the time domain offset is indicated by the aforementioned start indicator or clock acquisition section of Msg2, and the message content of Msg2 indicates the corresponding time domain offset for A-IoT device 1. For A-IoT device 2, no time domain offset is indicated by the aforementioned start indicator or clock acquisition section, and the message content of Msg2 does not indicate the corresponding time domain offset for A-IoT device 2. For A-IoT device 3, the time domain offset is indicated by the aforementioned start indicator or clock acquisition section of Msg2, and the message content of Msg2 indicates the corresponding time domain offset for A-IoT device 3.

[0251] When the reader receives multiple Msg1 responses along with a single Msg2, it broadcasts a Msg2 message to multiple A-IoT devices. The start indicator or clock acquisition portion of Msg2 uniformly indicates whether the multiple A-IoT devices should perform a time-domain offset. The message content of Msg2 indicates the time-domain offset for each A-IoT device. After receiving Msg2, each A-IoT device parses its own corresponding time-domain offset.

[0252] Multiple time-domain offsets in the Msg2 message content can be sorted according to the random IDs corresponding to the A-IoT devices. For example, if the time-domain offset value for A-IoT device 1 is 2RE, for A-IoT device 2 it is 4RE, and for A-IoT device 3 it is 6RE, then the message content would be: 2RE, 4RE, 6RE. As another example, if the time-domain offset value for A-IoT device 1 is 4RE, for A-IoT device 2 it is 6RE, and for A-IoT device 3 it is 2RE, then the message content would be: 2, 1, 3.

[0253] In some cases, if the A-IoT device supports time-domain offset, the preamble of Msg2 indicates a time-domain offset, but the message content of Msg2 does not indicate the amount of the time-domain offset. After receiving Msg2, the A-IoT device can use a default value as the time-domain offset value; for example, the default time-domain offset value can be 0. This application does not limit the value of the default value. It should be noted that different A-IoT devices may have different default time-domain offset values.

[0254] If the A-IoT device supports time-domain offset, the preamble of Msg2 indicates that no time-domain offset will be performed, the message content of Msg2 does not include the indication field, and the corresponding Msg3 reuses the time-domain resources of Msg1.

[0255] If the A-IoT device does not have time-domain offset capability, the preamble sequence of Msg2 does not need to indicate the time-domain offset, the message content of Msg2 does not include the indication field, and the corresponding Msg3 reuses the time-domain resources of Msg1.

[0256] In some other implementations, when the reader replies with a Msg2 for each Msg1 received, the start indicator or clock acquisition part of Msg2 can indicate the time domain offset.

[0257] Optionally, the start indicator of Msg2 corresponds to the sequence indicator time-domain offset.

[0258] For example, a time-domain offset value is predefined for each sequence. For instance, sequence 1 corresponds to a time-domain offset value of 1RE, sequence 2 corresponds to a time-domain offset value of 2RE, and sequence 3 corresponds to a time-domain offset value of 3RE. For example, when the sequence corresponding to the start indicator of Msg2 is sequence 1, the time-domain offset value corresponding to the A-IoT device is 1RE.

[0259] For example, a time-domain offset coefficient is predefined for each sequence. For instance, sequence 1 corresponds to time-domain offset coefficient m1, sequence 2 corresponds to time-domain offset coefficient m2, and sequence 3 corresponds to time-domain offset coefficient m3. For example, when the sequence corresponding to the start indicator of Msg2 is sequence 1, the time-domain offset coefficient corresponding to the A-IoT device is m1.

[0260] Optionally, the M value corresponding to the clock acquisition section of Msg2 indicates the time domain offset.

[0261] For example, a time-domain offset value is predefined for each M value. For instance, an M value of 2 corresponds to a time-domain offset value of 1RE; an M value of 4 corresponds to a time-domain offset value of 2RE; and an M value of 6 corresponds to a time-domain offset value of 3RE. For example, when the M value corresponding to the clock acquisition part of Msg2 is 4, it indicates that the time-domain offset value corresponding to the A-IoT device is 2RE.

[0262] For example, a time-domain offset coefficient is predefined for each M value. For instance, an M value of 2 corresponds to a time-domain offset coefficient m1, an M value of 4 corresponds to a time-domain offset coefficient m2, and an M value of 6 corresponds to a time-domain offset coefficient m3. For example, when the M value corresponding to the clock acquisition part of Msg2 is 4, the time-domain offset coefficient corresponding to the A-IoT device is m2.

[0263] Optionally, the M-value and repetition factor corresponding to the clock acquisition section of Msg2 indicate the time domain offset.

[0264] For example, a time-domain offset value corresponding to a predefined combination of M value and repetition factor is defined. For instance, an M value of 2 and a repetition factor of 2 correspond to a time-domain offset value of 1RE; an M value of 4 and a repetition factor of 4 correspond to a time-domain offset value of 2RE; and an M value of 6 and a repetition factor of 6 correspond to a time-domain offset value of 3RE. For example, when the M value corresponding to the clock acquisition part of Msg2 is 4 and the repetition factor is 4, the time-domain offset value corresponding to the A-IoT device is 2RE.

[0265] For example, a time-domain offset coefficient corresponding to a predefined combination of M value and repetition factor is defined. For instance, an M value of 2 and a repetition factor of 2 correspond to a time-domain offset coefficient m1; an M value of 4 and a repetition factor of 4 correspond to a time-domain offset coefficient m2; and an M value of 6 and a repetition factor of 6 correspond to a time-domain offset coefficient m3. For example, when the M value corresponding to the clock acquisition part of Msg2 is 4, the time-domain offset coefficient corresponding to the A-IoT device is m2.

[0266] When the time domain offset is directly indicated in the start indicator or clock acquisition section of Msg2, the message content section of Msg2 does not need to indicate the time domain offset.

[0267] S303, the A-IoT device sends a third message to the reader. Correspondingly, the reader receives the third message.

[0268] The third message can be Msg3 during the random access process. Msg3 includes the device ID and may also include any other upper-layer data.

[0269] With time-domain and frequency-domain resources specified in Msg2, the A-IoT device determines its own frequency-domain and time-domain resource locations based on the instructions in Msg2. The A-IoT device then uses the time-frequency resources configured in Msg2 to send Msg3 to the reader.

[0270] If Msg2 does not indicate time-domain resources but only frequency-domain resources, the A-IoT device uses the time-domain resources corresponding to Msg1 and the frequency-domain resources indicated by Msg2 to send Msg3.

[0271] If Msg2 does not indicate frequency domain resources but only time domain resources, the A-IoT device uses the frequency domain resources corresponding to Msg1 and the time domain resources indicated by Msg2 to send Msg3.

[0272] The information carried in Msg3 can be divided into multiple sets of options, including required options and several optional options. Required options include information that Msg3 must send, such as the device's identity document (ID), which uniquely identifies A-IoT devices. Specifically, the ID can be an Electronic Product Code (EPC). Optional options include other information, such as the device's remaining battery power, temperature, humidity, whether it participates in the current polling round, and whether it participates in the next polling round, etc.

[0273] If the time-domain resource size is insufficient to send the entire message, mandatory options can be sent based on the actual resource size, or mandatory options and some optional options can be sent. For example, different combinations of time slot lengths / guard interval lengths are associated with various optional options, and each combination of time-domain resource length and guard interval length corresponds to a set of mandatory and optional options. The A-IoT device can determine the mandatory and optional options for message 3 based on the time slot length and guard interval length indicated by Msg2.

[0274] It should be noted that the base station can also send Msg4 to A-IoT devices. Msg4 is a subsequent R2D transmission following D2R transmission.

[0275] In some embodiments, terms such as “send,” “report / distribute,” and “transmit” can be used interchangeably.

[0276] It should be understood that, in the various embodiments of this application, unless otherwise specified or in case of logical conflict, the terms and / or descriptions between different embodiments may be consistent and may be referenced by each other, and the technical features in different embodiments may be combined to form new embodiments according to their inherent logical relationships.

[0277] The communication method provided in the embodiments of this application has been described above with reference to Figures 1 to 4. The communication device for performing the above communication method provided in the embodiments of this application is described below.

[0278] Referring to Figure 5, which is a schematic diagram of the communication device provided in this application, the communication device 500 may include a communication unit 510 and optionally a processing unit 520. The communication unit 510 can implement corresponding communication functions, which can be internal communication within the communication device 500 or communication between the communication device 500 and other devices. The processing unit 520 can implement corresponding processing functions. The communication unit 510 may also be referred to as a communication interface or a transceiver unit. Optionally, the communication device 500 may further include a storage unit, which can be used to store instructions and / or data. The processing unit 520 can read the instructions and / or data from the storage unit to enable the communication device 500 to implement the aforementioned method embodiments.

[0279] In one possible design, the communication device 500 can be a network device in the above method embodiments, or it can be a module or chip applied to a network device. The communication device 500 can be used to execute the steps or processes performed by the network device in the above embodiments.

[0280] Specifically, the communication unit 510 is configured to: receive at least one first message, the first message being used to report whether the terminal device supports frequency offset and / or the supported frequency offset range, the frequency offset being an offset relative to the position of the frequency domain resource carrying the first message; send a second message, the second message indicating whether the terminal device performs frequency offset and / or the amount of frequency offset, and / or indicating time domain resources, the time domain resources being different from the time domain resources carrying the first message; receive a third message, in which case if the second message indicates that the terminal device performs frequency offset and indicates time domain resources, the third message is carried on the time-frequency resources determined based on the second message, and in which case if the second message does not indicate that the terminal device performs frequency offset and / or time domain resources, the third message is carried using the frequency domain resources and / or time domain resources carrying the first message.

[0281] In one possible design, the communication device 500 can be the terminal device in the above method embodiments, or it can be a module or chip applied to the second device. The communication device 500 can be used to execute the steps or processes performed by the terminal device in the above embodiments.

[0282] Specifically, the communication unit 510 is configured to: send a first message, which is used to report whether the terminal device supports frequency offset and / or the supported frequency offset range, wherein the frequency offset is an offset relative to the position of the frequency domain resource carrying the first message; receive a second message, which indicates whether the terminal device performs frequency offset and / or the amount of frequency offset, and / or indicates time domain resources, wherein the time domain resources are different from the time domain resources carrying the first message; and send a third message, wherein if the second message indicates that the terminal device performs frequency offset and indicates time domain resources, the third message is carried on the time-frequency resources determined based on the second message, and if the second message does not indicate that the terminal device performs frequency offset and / or time domain resources, the third message is carried on the frequency domain resources and / or time domain resources carrying the first message.

[0283] For details regarding the steps or processes executed by each unit in the communication device 500, please refer to the above method embodiments; they will not be described in detail here.

[0284] It should be understood that the "unit" in the communication device 500 can be implemented in hardware, software, or by hardware executing corresponding software. For example, the "unit" can refer to an application-specific integrated circuit (ASIC), electronic circuitry, a processor (e.g., a shared processor, a proprietary processor, or a group processor, etc.) and memory for executing one or more software or firmware programs, combined logic circuitry, and / or other suitable components supporting the described functions. As another example, the communication unit 510 can be replaced by a transceiver circuit (e.g., it may include receiving and transmitting circuitry), and the processing unit 520 can be replaced by a processor or processing circuitry.

[0285] Referring to Figure 6, which is a schematic diagram of the structure of a communication device 600 applicable to an embodiment of this application. The device 600 can be a communication equipment, or a chip, chip system, or processor that supports the communication equipment in implementing the above methods. The communication equipment can be a terminal device or a network device. This device can be used to implement the methods described in the above method embodiments; for details, please refer to the descriptions in the above method embodiments.

[0286] The communication device 600 includes one or more processors 601, which can also be called processing units, and can perform certain control functions. The processor 601 can be a general-purpose processor or a special-purpose processor, etc.

[0287] In an alternative design, the processor 601 may also store instructions and / or data that can be executed by the processor 601 to cause the communication device 600 to perform the methods described in the above method embodiments.

[0288] Optionally, the communication device 600 may include one or more memories 602, which may store instructions that can be executed on the processor 601, causing the communication device 600 to perform the methods described in the above method embodiments. Optionally, the memories 602 may also store data. Optionally, the processor 601 may also store instructions and / or data. The processor 601 and the memories 602 may be provided separately or integrated together.

[0289] In another alternative design, the communication device 600 may include a communication interface 603 for implementing receiving and transmitting functions. For example, the communication interface 603 may be a transceiver circuit, interface, interface circuit, or transceiver. The transceiver circuit, interface, interface circuit, or transceiver for implementing receiving and transmitting functions may be separate or integrated. The aforementioned transceiver circuit, interface, interface circuit, or transceiver may be used for reading and writing code / data, or it may be used for transmitting or relaying signals.

[0290] Those skilled in the art will understand that, for ease of explanation, Figure 6 only shows one memory and one processor. In actual devices, multiple processors and memories may exist. Memory may also be referred to as storage medium or storage device, etc., and the embodiments of this application do not impose such limitations.

[0291] It should be understood that, in one possible design, the steps in the method embodiments provided in this application can be implemented by integrated logic circuits in the processor's hardware or by instructions in software form. The steps of the methods disclosed in the embodiments of this application can be directly implemented by a hardware processor, or implemented by a combination of hardware and software modules in the processor. The software modules can reside in random access memory, flash memory, read-only memory, programmable read-only memory, electrically erasable programmable memory, registers, or other mature storage media in the art. This storage medium is located in memory, and the processor reads information from the memory and, in conjunction with its hardware, completes the steps of the above method. To avoid repetition, detailed descriptions are not provided here.

[0292] It should be noted that the processor in the embodiments of this application can be an integrated circuit chip with signal processing capabilities. In implementation, the steps of the above method embodiments can be completed by the integrated logic circuitry in the processor's hardware or by software instructions.

[0293] In the embodiments of this application, the processor can be a CPU, or other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. A general-purpose processor can be a microprocessor or any conventional processor. The steps of the method disclosed in the embodiments of this application can be directly manifested as execution by a hardware decoding processor, or execution by a combination of hardware and software modules in the decoding processor. The software modules can reside in random access memory, flash memory, read-only memory, programmable read-only memory, electrically erasable programmable memory, registers, or other mature storage media in the art. This storage medium is located in memory; the processor reads information from the memory and, in conjunction with its hardware, completes the steps of the above method.

[0294] It should be understood that, in the embodiments of this application, the memory may include read-only memory and random access memory, and provides instructions and data to the processor. The memory may also include non-volatile random access memory. The memory may be volatile memory or non-volatile memory, or may include both. The non-volatile memory may be read-only memory (ROM), programmable read-only memory (PROM), erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), or flash memory. The volatile memory may be random access memory (RAM), which serves as an external cache. By way of example, but not limitation, many forms of RAM are available, such as static random access memory (SRAM), dynamic random access memory (DRAM), synchronous dynamic random access memory (SDRAM), double data rate synchronous dynamic random access memory (DDR SDRAM), enhanced synchronous dynamic random access memory (ESDRAM), synchronous linked dynamic random access memory (SLDRAM), and direct rambus RAM (DR RAM).

[0295] This application provides a communication network, including at least one application function entity, at least one network device, and at least one read / write device. The application entity is used to execute the steps of application function execution in the method embodiment, the network device is used to execute the steps of core network execution in the method embodiment, and the read / write device is used to execute the steps of reader execution in the method embodiment.

[0296] This application provides a computer storage medium that stores a computer program (also referred to as code or instructions) that, when run on a computer, causes the computer to perform the methods of this application.

[0297] This application provides a computer program product containing instructions, which includes a computer program (also referred to as code or instructions) that, when run, causes a computer to perform the method of this application embodiment.

[0298] The above embodiments can be implemented, in whole or in part, by software, hardware, firmware, or any other combination thereof. When implemented using software, the above embodiments can be implemented, in whole or in part, as a computer program product. This computer program product includes one or more computer instructions or computer programs. When the computer instructions or computer program are loaded or executed on a computer, all or part of the processes or functions according to the embodiments of this application are generated. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions can be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another. For example, the computer instructions can be transmitted from one website, computer, server, or data center to another website, computer, server, or data center via wired (e.g., infrared, wireless, microwave, etc.) means. The computer-readable storage medium can be any available medium that a computer can access or a data storage device such as a server or data center that includes one or more sets of available media. The available medium can be a magnetic medium (e.g., floppy disk, hard disk, magnetic tape), an optical medium (e.g., DVD), or a semiconductor medium. A semiconductor medium can be a solid-state drive.

[0299] Those skilled in the art will recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0300] Those skilled in the art will understand that, for the sake of convenience and brevity, the specific working processes of the systems, devices, and units described above can be referred to the corresponding processes in the foregoing method embodiments, and will not be repeated here.

[0301] In the several embodiments provided in this application, it should be understood that the disclosed systems, apparatuses, and methods can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative; for instance, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be through some interfaces; the indirect coupling or communication connection between apparatuses or units may be electrical, mechanical, or other forms.

[0302] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0303] In addition, the functional units in the various embodiments of this application can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit.

[0304] If the aforementioned functions are implemented as software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or a portion of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of this application. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0305] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A communication method, characterized in that, Applied to network devices, the method includes: Receive at least one first message, the first message being used to report whether the terminal device supports frequency offset and / or the supported frequency offset range, the frequency offset being an offset relative to the frequency domain resource location carrying the first message; Send a second message, the second message indicating whether the terminal device performs frequency offset and / or frequency offset amount, and / or indicating time domain resources, the time domain resources being different from the time domain resources carrying the first message; Upon receiving a third message, if the second message instructs the terminal device to perform a frequency offset and indicates time-domain resources, the third message carries time-frequency resources determined based on the second message; if the second message does not instruct the terminal device to perform a frequency offset and / or time-domain resources, the third message carries the frequency-domain resources and / or time-domain resources that carried the first message.

2. The method according to claim 1, characterized in that, The message content of the first message, or the time-frequency position of the first message, or the random sequence corresponding to the first message, indicates whether the terminal device supports frequency offset and / or the supported frequency offset range.

3. The method according to claim 1 or 2, characterized in that, The frequency offset range includes: multiple frequency offsets, or frequency offset range groupings, or the maximum value of the frequency offset.

4. The method according to any one of claims 1 to 3, characterized in that, The start indicator or clock acquisition section of the second message indicates whether the terminal device performs a frequency shift.

5. The method according to claim 4, characterized in that, When the start indicator or clock acquisition section of the second message indicates that the terminal device is to perform a frequency offset, the message content of the second message indicates the frequency offset amount.

6. The method according to claim 4 or 5, characterized in that, If the terminal device is instructed to perform a frequency offset in the start indicator or clock acquisition section of the second message, and the message content of the second message does not indicate the frequency offset amount, the frequency offset amount corresponding to the terminal device is a predefined value.

7. The method according to any one of claims 4 to 6, characterized in that, The duration of the high and low levels corresponding to the start indicator of the second message indicates whether the terminal device performs a frequency shift.

8. The method according to claim 7, characterized in that, Whether the total duration of the high level and the total duration of the low level corresponding to the start indicator of the second message are the same indicates whether the terminal device should perform frequency shift; Alternatively, whether the duration of the high level and the duration of the low level of the i-th level segment corresponding to the start indicator of the second message are the same indicates whether the terminal device performs a frequency shift, where i is an integer ≥ 1.

9. The method according to any one of claims 4 to 8, characterized in that, The M value corresponding to the clock acquisition part of the second message indicates whether the terminal device performs frequency shift; Alternatively, the M value and repetition factor corresponding to the clock acquisition portion of the second message indicate whether the terminal device performs a frequency offset.

10. The method according to claim 8, characterized in that, The M value corresponding to the clock acquisition part of the second message instructs the terminal device to perform frequency offset, including: the M value corresponding to the clock acquisition part of the second message instructs the frequency offset range grouping; Alternatively, the M value and repetition factor corresponding to the clock acquisition portion of the second message instructing the terminal device to perform frequency offset includes: the M value and repetition factor corresponding to the clock acquisition portion of the second message indicating frequency offset range grouping.

11. The method according to claim 5, characterized in that, In the case where the message content of the second message includes multiple frequency offsets, the multiple frequency offsets are ordered according to random identifiers.

12. The method according to any one of claims 1 to 3, characterized in that, The start indicator or clock acquisition section of the second message indicates the frequency offset.

13. The method according to any one of claims 1 to 12, characterized in that, The frequency offset includes one of the following: frequency offset value, identifier of frequency offset value, and coefficient of frequency offset, wherein the coefficient is an integer multiple of the minimum chip length corresponding to the message encoding method.

14. The method according to any one of claims 1 to 13, characterized in that, The time-domain resources include at least one of the following: the time slot length and protection interval length occupied by the third message, the time-domain start time, and the time-domain end time.

15. The method according to claim 14, characterized in that, The information carried in the message content of the third message is associated with the time slot length and the protection interval length.

16. A communication method, characterized in that, Applied to a terminal device, the method includes: Send a first message, which is used to report whether the terminal device supports frequency offset and / or the supported frequency offset range, wherein the frequency offset is the offset relative to the subcarrier position of the first message; Receive a second message, the second message indicating whether the terminal device performs frequency offset and / or frequency offset amount, and / or indicating time domain resources, the time domain resources being different from the time domain resources carrying the first message; Upon receiving a third message, if the second message instructs the terminal device to perform a frequency offset and indicates time-domain resources, the third message carries time-frequency resources determined based on the second message; if the second message does not instruct the terminal device to perform a frequency offset and / or time-domain resources, the frequency-domain resources and / or time-domain resources carrying the first message are used to carry the third message, and the first message, the second message, and the third message are used for one uplink synchronization of the terminal device.

17. The method according to claim 16, characterized in that, The message content of the first message, or the time-frequency position of the first message, or the random sequence corresponding to the first message, indicates whether the terminal device supports frequency offset and / or the supported frequency offset range.

18. The method according to claim 16 or 17, characterized in that, The frequency offset range includes: multiple frequency offsets, or frequency offset range groupings, or the maximum value of the frequency offset.

19. The method according to any one of claims 16 to 18, characterized in that, The start indicator or clock acquisition section of the second message indicates whether the terminal device performs a frequency shift.

20. The method according to claim 19, characterized in that, When the start indicator or clock acquisition section of the second message indicates that the terminal device is to perform a frequency offset, the message content of the second message indicates the frequency offset amount.

21. The method according to claim 19 or 20, characterized in that, If the terminal device is instructed to perform a frequency offset in the start indicator or clock acquisition section of the second message, and the message content of the second message does not indicate the frequency offset amount, the frequency offset amount corresponding to the terminal device is a predefined value.

22. The method according to any one of claims 19 to 21, characterized in that, The duration of the high and low levels corresponding to the start indicator of the second message indicates whether the terminal device performs a frequency shift.

23. The method according to claim 22, characterized in that, Whether the total duration of the high level and the total duration of the low level corresponding to the start indicator of the second message are the same indicates whether the terminal device should perform frequency shift; Alternatively, whether the duration of the high level and the duration of the low level of the i-th level segment corresponding to the start indicator of the second message are the same indicates whether the terminal device performs a frequency shift, where i is an integer ≥ 1.

24. The method according to any one of claims 19 to 21, characterized in that, The M value corresponding to the clock acquisition part of the second message indicates whether the terminal device performs frequency shift; Alternatively, the M value and repetition factor corresponding to the clock acquisition portion of the second message indicate whether the terminal device performs a frequency offset.

25. The method according to claim 24, characterized in that, The M value corresponding to the clock acquisition part of the second message instructs the terminal device to perform frequency offset, including: the M value corresponding to the clock acquisition part of the second message instructs the frequency offset range grouping; Alternatively, the M value and repetition factor corresponding to the clock acquisition portion of the second message instructing the terminal device to perform frequency offset includes: the M value and repetition factor corresponding to the clock acquisition portion of the second message indicating frequency offset range grouping.

26. The method according to claim 20, characterized in that, In the case where the message content of the second message includes multiple frequency offsets, the multiple frequency offsets are ordered according to random identifiers.

27. The method according to any one of claims 16 to 18, characterized in that, The start indicator or clock acquisition section of the second message indicates the frequency offset.

28. The method according to any one of claims 16 to 27, characterized in that, The frequency offset includes one of the following: frequency offset value, identifier of frequency offset value, frequency offset coefficient, wherein the coefficient is an integer multiple of the minimum chip length corresponding to the message encoding method.

29. The method according to any one of claims 16 to 28, characterized in that, The time-domain resources include at least one of the following: the time slot length and protection interval length occupied by the third message, the time-domain start time, and the time-domain end time.

30. The method according to claim 29, characterized in that, The information carried in the message content of the third message is associated with the time slot length and the protection interval length.

31. A communication device, characterized in that, include: A processor coupled to a memory for storing programs or instructions, which, when executed by the processor, cause the communication device to perform: the method as claimed in any one of claims 1-15, or the method as claimed in any one of claims 16-30.

32. A communication device, characterized in that, It includes a processor and an interface for sending and / or receiving signals, such that the processor performs the method as claimed in any one of claims 1-15, or the method as claimed in any one of claims 16-30.

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