Information acquisition method and related equipment

Abstract

The present application provides a method for acquiring information and related equipment, relating to the field of communication technology. The method for acquiring information can be applied to R2D scenarios or other low-rate communication scenarios of A‑IoT systems. The method utilizes the principle that the duration of OFDM symbols remains unchanged, and after the M value changes, the number of sampling points at the receiving end for different level states will change, and the duration corresponding to the different level states will also change accordingly. A scheme is designed in which the receiving end calculates the changed M value based on the actual number of sampling points or the actual chip duration. After the M value changes, the receiving end can synchronously obtain the changed M value, thereby avoiding problems such as clock synchronization and demodulation at the receiving end caused by the change in the M value, and improving the communication quality between the transmitting end and the receiving end in the R2D scenario.

Description

Technical Field

[0001] The present application relates to the field of communication technology, and in particular to a method for obtaining information and related equipment. Background Art

[0002] In the ambient internet of things (Ambient IoT) system, the transmitter and receiver (device) modulate the data to be transmitted onto a carrier for information transmission. To address multipath fading and other issues brought about by complex channel environments, Ambient IoT typically uses orthogonal frequency division multiplexing (OFDM) technology for communication. This technology replicates the tail signal of an OFDM symbol as a cyclic prefix (CP) and inserts it into the OFDM symbol header. This effectively mitigates inter-symbol interference (ISI) and inter-carrier interference (ICI) caused by multipath effects, ensuring subcarrier orthogonality.

[0003] However, in some communication scenarios of Ambient IoT, CP insertion may introduce erroneous rising or falling edges into OFDM symbols, affecting the accuracy of received signals. Summary of the Invention

[0004] An embodiment of the present application provides a method for obtaining information, which is used to solve the problem that after the transmitting end changes the value of the number of code chips M in the OFDM symbol, the receiving end cannot obtain the changed value of M.

[0005] The information acquisition method provided in this application utilizes the principle that the duration of the OFDM symbol remains unchanged. After the M value changes, the number of sampling points at the receiving end for different level states will change, and the duration corresponding to the different level states will also change accordingly. A scheme is designed for the receiving end to calculate the changed M value based on the actual number of sampling points or the actual chip duration. After the M value changes, the receiving end can synchronously obtain the changed M value, thereby avoiding problems such as clock synchronization and demodulation at the receiving end caused by the change in the M value, thereby improving the communication quality between the transmitter and the receiver in the R2D scenario.

[0006] Manchester coding uses level transitions to represent bits. An OFDM symbol consists of two level states, each corresponding to a chip. When the transmitter changes the number of chips M in the OFDM symbol, the receiver can The relationship between the number of reference sampling points and the changed M value is obtained. The number of reference sampling points refers to the number of sampling points corresponding to the reference chip duration when the M value is unchanged. According to the characteristics of Manchester encoding, the reference chip duration includes four situations: the first reference chip duration , its value is a standard chip duration ; Second benchmark chip duration , whose value is two standard durations The sum of the third benchmark chip duration , its value is a standard chip duration and the duration of the OFDM symbol cyclic prefix CP The sum of the fourth benchmark chip duration , its value is two standard chip durations and the duration of the OFDM symbol cyclic prefix CP The sum of the standard chip duration. When the value of M is unchanged, the duration of the OFDM symbol excluding the CP is divided into M equal parts.

[0007] In one possible implementation, when When, we can use the formula Calculate the changed M value.

[0008] In one possible implementation, when When, if The number of sampling points is different from the reference sampling points. At this time, the receiving end can distinguish is abnormal, but at this time, discard the current , do not use this to calculate the changed M value, but continue to obtain the next actual number of sampling points , and according to the number of the next actual sampling points Calculate the changed M value. The changed M value is calculated according to the following formula: ;like , the changed M value is calculated according to the following formula: .

[0009] In one possible implementation, when When, if The number of sampling points is the same as one of the reference sampling points. In this case, the receiver cannot distinguish If it is abnormal, the next actual sampling point number will be obtained. , and according to the number of the next actual sampling points Calculate the changed M value. If the value of M is 2 when it is not changed, then when the OFDM symbol duration and CP duration are specific values ​​(such as the specific values ​​specified in the 3GPP standard, such as , or ), The number of sampling points is different from the reference sampling points. At this time, the receiving end can distinguish is abnormal, so discard , get the next actual sampling point number , and according to the number of the next actual sampling points Calculate the changed M value. , the changed M value is calculated according to the following formula: ;like , the changed M value is calculated according to the following formula: .

[0010] In addition to obtaining the changed M value based on the number of sampling points, the receiver can also obtain the actual chip duration based on the number of sampling points, and obtain the changed M value based on the relationship between the actual chip duration and the benchmark chip duration.

[0011] In a first aspect, a method for obtaining information is provided, the method comprising: obtaining the number of sampling points for an OFDM symbol; obtaining a changed M value of the OFDM symbol based on the number of sampling points, the M value being used to indicate the number of chips included in the OFDM symbol.

[0012] In a second aspect, an electronic device is provided, comprising: a processor; a memory; the memory stores a computer program, the computer program comprising instructions, which, when executed by the processor, enable the electronic device to execute the method described in any implementation of the first aspect above.

[0013] In a third aspect, a communication device is provided, comprising a processor. The processor is coupled to a memory and can be configured to execute instructions or data in the memory to implement the method of any possible implementation of the first aspect. Optionally, the communication device further comprises a memory. Optionally, the communication device further comprises a communication interface, the processor being coupled to the communication interface.

[0014] In one implementation, the communication interface may be a transceiver, or an input / output interface.

[0015] In another implementation, the communication device is a chip configured in a terminal device. When the communication device is a chip configured in a terminal device, the communication interface may be an input / output interface.

[0016] In a fourth aspect, a processor is provided, comprising: an input circuit, an output circuit, and a processing circuit. The processing circuit is configured to receive a signal through the input circuit and transmit a signal through the output circuit, so that the processor executes the method in any possible implementation of any aspect.

[0017] In a specific implementation, the processor may be one or more chips, the input circuit may be an input pin, the output circuit may be an output pin, and the processing circuit may be a transistor, a gate circuit, a trigger, or various logic circuits. The input signal received by the input circuit may be, for example, but not limited to, received and input by a receiver, and the signal output by the output circuit may be, for example, but not limited to, output to and transmitted by a transmitter. The input circuit and the output circuit may be the same circuit, which functions as an input circuit and an output circuit at different times. The embodiments of the present application do not limit the specific implementation of the processor and various circuits.

[0018] In a fifth aspect, a computer program product is provided, comprising: a computer program (also referred to as code, or instructions), which, when executed, enables a computer to execute a method in any possible implementation of any of the above aspects.

[0019] In a sixth aspect, a computer-readable storage medium is provided, which stores a computer program (also referred to as code, or instructions) which, when run on a computer, enables the computer to execute a method in any possible implementation of any of the above aspects.

[0020] In a seventh aspect, embodiments of the present application provide a chip system comprising one or more processors configured to retrieve and execute instructions stored in a memory, thereby executing the method of each of the above aspects or any possible implementation of each aspect. The chip system may be composed of a chip or may include a chip and other discrete devices.

[0021] Among them, the chip system may include an input circuit or interface for sending information or data, and an output circuit or interface for receiving information or data.

[0022] In an eighth aspect, a communication system is provided, including a transmitter and a receiver. Optionally, the communication system may further include other devices communicating with the transmitter and / or the receiver. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 A schematic diagram showing level transitions in a Manchester encoding method provided in an embodiment of the present application.

[0024] Figure 2A schematic diagram of an actual chip duration provided in an embodiment of the present application.

[0025] Figure 3A and Figure 3B This is a schematic diagram of introducing erroneous rising or falling edges when inserting CPs into OFDM symbols provided in some embodiments of the present application.

[0026] Figure 4A and Figure 4B Some schematic diagrams of avoiding erroneous transition edges by changing the M value are provided in the embodiments of the present application.

[0027] Figure 5A and Figure 5B Some schematic diagrams of obtaining the changed M values ​​provided in the embodiments of the present application.

[0028] Figures 6A to 6C Schematic diagrams of other methods for obtaining modified M values ​​provided in embodiments of the present application.

[0029] Figure 7 A schematic flowchart of a method for obtaining information provided in an embodiment of the present application.

[0030] Figure 8 A schematic diagram of a wireless communication system 10 provided in an embodiment of the present application.

[0031] Figure 9 A schematic structural diagram of an electronic device 100 provided in an embodiment of the present application.

[0032] Figure 10 It is a schematic structural diagram of a receiving end 1000 provided in an embodiment of the present application. DETAILED DESCRIPTION

[0033] It should be noted that the terms used in the implementation methods section of the embodiments of the present application are only used to explain the specific embodiments of the present application, and are not intended to limit the present application. In the description of the embodiments of the present application, unless otherwise specified, " / " means or, for example, A / B can mean A or B; "and / or" in this article is merely a way to describe the association relationship of associated obstacles, indicating that there can be three relationships, for example, A and / or B can mean: A exists alone, A and B exist at the same time, and B exists alone. In addition, in the description of the embodiments of the present application, unless otherwise specified, "multiple" means two or more than two, "at least one" and "one or more" mean one, two or more than two.

[0034] In the following, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly specifying the number of the technical features indicated. Therefore, the definition of "first" and "second" features may explicitly or implicitly include one or more of the features.

[0035] References to "one embodiment" or "some embodiments" in this specification mean that a particular feature, structure, or characteristic described in conjunction with that embodiment is included in one or more embodiments of the present application. Thus, phrases such as "in one embodiment," "in some embodiments," "in other embodiments," and "in yet other embodiments" appearing in various places in this specification do not necessarily refer to the same embodiment, but rather mean "one or more, but not all, embodiments," unless otherwise specifically emphasized. The terms "including," "comprising," "having," and variations thereof mean "including but not limited to," unless otherwise specifically emphasized.

[0036] The following specific embodiments are used to describe the technical solution of the present application in detail. The following specific embodiments can be combined with each other, and the same or similar concepts or processes may not be described in detail in some embodiments.

[0037] In order to better understand the channel monitoring method provided in the embodiments of the present application, the following first introduces the terms or concepts that may be involved in the present application.

[0038] 1. Ambient IoT (A-IoT)

[0039] Ambient IoT is a wireless sensing technology based on ambient energy harvesting. Ambient IoT devices utilize energy from their surroundings, such as light, heat, and radio waves, and convert this energy into electricity through energy harvesting technology to power the devices. The devices then transmit signals through backscatter and low-power radio frequency methods, enabling low-throughput data transmission. Powered by ambient energy, Ambient IoT devices require minimal external energy input or no batteries, operating at power levels as low as microwatts, ensuring long-term stable operation.

[0040] 2. Reader to device (R2D)

[0041] In the Ambient IoT, R2D scenarios are an important link in realizing data transmission and interaction between readers and environmental IoT devices (such as electronic tags, cargo status monitors, smart switches, temperature and humidity sensors, etc.). They are of great significance for promoting the application of the Environmental IoT in smart cities, industrial automation, smart homes and other fields.

[0042] The R2D scenario involves downlink transmission, primarily consisting of a preamble and a physical transmission channel. The physical transmission channel, referred to as the physical reader-to-device channel (PRDCH), involves three steps: cyclic redundancy check (CRC), linear encoding, and R2D waveform generation. In R2D communication scenarios, given the energy constraints and low processing power of devices, the R2D waveform is designed as an on-off keying (OOK) waveform based on OFDM modulation. By modulating the transmitted data into an OOK waveform, devices can recover the original data based on the presence or absence of a detected signal, enabling simple, low-power communication.

[0043] 3. Cyclic Prefix (CP)

[0044] The cyclic prefix is ​​formed by copying a signal segment from the end of an OFDM symbol to the beginning of the symbol. The cyclic prefix is ​​primarily used to mitigate ISI and inter-subcarrier interference (ICI) caused by multipath. In a wireless channel, signals travel through multiple paths to the receiver, arriving at different times, which can cause interference between successive symbols. The presence of a CP ensures that the multipath components of each OFDM symbol fall completely within the symbol, provided the multipath delay is less than the CP length. This ensures orthogonality between subcarriers, avoids ISI and ICI, and significantly improves the system's anti-interference capability and transmission reliability.

[0045] In the discussion of Ambient IoT in the 3rd Generation Partnership Project (3GPP) Release 19 (R19), regarding the modulation part of the R2D scenario, according to TR38.769, the following are the processing of CP:

[0046] For cyclic prefix handling, the following candidate methods are studied based on aspects such as the impact of CP on R2D timing acquisition, PRDCH decoding and performance, reader and device implementation complexity, interference between R2D and NR downlink / uplink if in the same new radio (NR) frequency band, and spectral efficiency.

[0047] Method Type 1: The cyclic prefix is ​​removed at the device end, and no specific provisions are made at the transmitting end.

[0048] Method type 2: Ensure that when a cyclic prefix is ​​inserted into an OFDM-based waveform, no false rising / falling edges are introduced between the last on-off keying (OOK) chip of OFDM symbol (n-1) and the first OOK chip of OFDM symbol n.

[0049] For method type 2, two approaches are studied for subcarrier orthogonality:

[0050] Alternative M2-1: Method type 2 maintains subcarrier orthogonality, i.e., the cyclic prefix is ​​copied from the end of one OFDM symbol.

[0051] Alternative M2-1-1: The first OOK chip (or OOK chips) and the last OOK chip (or OOK chips) in an OFDM symbol are the same.

[0052] Alternative M2-1-2: Ensure that one transition edge occurs only at the beginning of the cyclic prefix or only at the end of the cyclic prefix, and no transition edge occurs during the cyclic prefix.

[0053] It should be noted that the information acquisition method provided in the embodiment of the present application is proposed based on the above discussion of method type 2.

[0054] 4. Manchester encoding

[0055] Manchester coding is a coding method that uses level transitions to represent binary information (0 or 1) to be transmitted. There are different conventions for representing level transitions. For example Figure 1 As shown in the figure, one representation proposed by GE Thomas et al. is that a low-to-high level transition is used to represent "0" in a code element, and a high-to-low level transition is used to represent "1"; another representation specified by IEEE 802.3 is that a low-to-high level transition is used to represent "1" in a code element, and a high-to-low level transition is used to represent "0".

[0056] R2D communication in the Ambient IoT uses Manchester encoding. Each code element corresponds to two levels (one high and one low). Level transitions are used to synchronize clock and data transmission. Each level in a code element corresponds to a chip, meaning that a Manchester-encoded code element contains two chips.

[0057] 5. Signal reception at the receiving end in R2D communication

[0058] After receiving the OFDM signal, the receiver may not be able to directly distinguish the boundaries of different OFDM symbols due to hardware limitations or complex channel environment. However, the receiver can use pre-configured sampling parameters (such as sampling frequency) to ) to sample the received signal.

[0059] Since different level states correspond to specific sampling numbers under the Manchester coding rule, the receiving end can determine the duration of different level states by combining the number of sampling points with the known sampling frequency. In the embodiment of the present application, the number of sampling points corresponding to different level states in the OFDM symbol obtained by the receiving end can be defined as the actual number of sampling points. or Indicates that the duration obtained based on the actual number of sampling points is defined as the actual chip duration. In this embodiment of the application, or It is understood that the actual chip duration corresponds to the duration of the continuous same level state in the OFDM symbol, which can be equal to the duration of one chip or two chips in terms of value, rather than strictly corresponding to a single chip.

[0060] In the embodiment of the present application, for the convenience of description, the first actual chip duration, the second actual chip duration, etc. are defined. The first actual chip duration may refer to the actual duration of the first chip including the OFDM symbol. Figure 2 For example, the first actual chip duration of OFDM symbol n can be equal to the sum of the last chip duration of OFDM symbol (n-1), the CP duration of OFDM symbol n, and the first chip duration of OFDM symbol n, where n is any integer greater than or equal to 1. The second actual chip duration of OFDM symbol n can be equal to the duration of two consecutive chips with the same level. In other cases, the second actual chip duration can also be equal to the duration of a single chip, depending on the specific bit information represented by the OFDM symbol.

[0061] Based on the above introduction, OFDM technology is currently widely used for R2D communication in the ambient IoT. In Manchester encoding, an M value is introduced for each OFDM symbol to represent the number of chips it contains. When communicating based on OFDM technology, a CP is typically inserted before each OFDM symbol. This CP is a signal copied from the end of the OFDM symbol. Because the signal level at the end of the copied OFDM symbol may differ from the level at the beginning of the OFDM symbol, the OFDM symbol after the CP insertion may exhibit erroneous rising or falling edges (or collectively, transition edges).

[0062] For example, assuming an OFDM symbol n consists of 6 chips (i.e., M is 6), when inserting a CP before the OFDM symbol, part of the signal in the last chip at the end of OFDM symbol n can be copied as the CP. For ease of description, the level state of the last chip of OFDM symbol (n-1) is recorded as a, the level state of the first chip of OFDM symbol n is recorded as b, and the level state of the last chip of OFDM symbol n is recorded as c. Based on the discussion in method type 2 above, a=b must exist. However, if a=b≠c is satisfied, then inserting a CP will introduce an erroneous transition edge in the OFDM symbol. For example, see Figure 3A , the last chip of OFDM symbol (n-1) and the first chip of OFDM symbol n are both low, and the last chip of OFDM symbol n is high. Then, when part of the signal in the last chip of OFDM symbol n is copied as CP and inserted into the head of OFDM symbol n, an erroneous falling edge will be introduced. Similarly, see Figure 3B , the last chip of OFDM symbol (n-1) and the first chip of OFDM symbol n are both high level, and the last chip of OFDM symbol n is low level, then an erroneous rising edge will be introduced when inserting CP into OFDM symbol n.

[0063] Under Manchester encoding, the receiver samples bits and extracts information based on level transitions within a symbol. However, an erroneous rising or falling edge in an OFDM symbol disrupts the inherent level transitions of Manchester encoding, causing the corresponding transition characteristics at the receiver's sampling moment to shift. This in turn leads to bit sampling errors, compromising the accuracy of received information. Furthermore, erroneous transitions can disrupt the orthogonality between OFDM subcarriers, introducing ISI and ICI, which can increase the bit error rate.

[0064] It should be noted that in different scenarios, the duration of the CP can be determined based on specific application requirements and channel characteristics. In some cases, if the number of chips in an OFDM symbol is large (i.e., the M value is large), the duration of a single chip is short, and the duration of the CP may correspond to the duration of multiple consecutive chips. In this case, multiple chips at the end of the OFDM symbol will be copied as the CP, and a transition edge will appear during the CP. In other cases, if the number of chips in an OFDM symbol is small (i.e., the M value is small), the duration of a single chip is long, and the duration of the CP may correspond to the duration of one or less than one chip. In this case, a chip at the end of the OFDM symbol or part of the signal in a chip will be copied as the CP. There is no transition edge during the CP, but a transition edge may appear at the beginning or end of the CP. Since the information acquisition method provided in the embodiment of the present application is proposed based on the discussion of method type 2, based on the alternative scheme M2-1-2 in the discussion, this scheme is applicable to the situation where there is no transition edge during the CP, but a transition edge may appear at its beginning or end. Therefore, the embodiment of the present application mainly relates to the former situation, and the other situation is not discussed.

[0065] To avoid false transitions caused by inserting a CP when a = b ≠ c, the 120th 3GPP meeting proposed Scheme M2, which uses Manchester coding for R2D. Alternative M2-1-2 proposes changing the value of M to the adjacent M+1, thus transforming the case of a = b ≠ c into a = b = c. Discussions at the meeting led to the following agreement: For Alternative M2-1-2, a detailed design will be developed based on Proposal 4. Specifically, for OFDM symbol n, the value of M will be changed to the adjacent M±1, thus transforming the case of a = b ≠ c into a = b = c.

[0066] Among them, a specific way to change the M value is to shift the chip in the OFDM symbol to the adjacent subsequent OFDM symbol, for example, by shifting the last chip in OFDM symbol n backward to OFDM symbol (n+1), so that the M value of OFDM symbol n is changed to (M-1).

[0067] Take changing the M value to (M-1) as an example, Figure 4A and Figure 4B As shown in FIG, some schematic diagrams of avoiding erroneous transition edges by changing the M value are provided in the embodiments of the present application. Figure 4A, the level states of the last chip of OFDM symbol (n-1) and the first chip of OFDM symbol n are both low, while the level state of the last chip of OFDM symbol n is high. If the M value is not changed, then when a portion of the signal from the last chip of OFDM symbol n is copied and inserted as the CP into the header of OFDM symbol n, an erroneous falling edge will be introduced into OFDM symbol n. However, if the last chip of OFDM symbol n is shifted to the adjacent OFDM symbol (n+1), the M value is changed to (M-1) (for example, changing the M value of OFDM symbol n from 6 to 5), the level state of the last chip of OFDM symbol n becomes low. In this case, copying a portion of the signal from the last chip of OFDM symbol n as the CP will not introduce an erroneous level transition.

[0068] Similarly, if the level state is opposite, the same principle applies. Figure 4B , the level states of the last chip of OFDM symbol (n-1) and the first chip of OFDM symbol n are both high, while the level state of the last chip of OFDM symbol n is low. If the M value is not changed, then when a portion of the signal from the last chip of OFDM symbol n is copied and inserted as the CP into the header of OFDM symbol n, an erroneous rising edge will be introduced into OFDM symbol n. However, if the last chip of OFDM symbol n is shifted to the adjacent OFDM symbol (n+1), the M value is changed to (M-1) (for example, changing the M value of OFDM symbol n from 6 to 5), the level state of the last chip of OFDM symbol n becomes high. At this time, copying a portion of the signal from the last chip of OFDM symbol n as the CP will not introduce an erroneous level transition.

[0069] As shown in the above example, changing the M value in the OFDM symbol to adjacent M±1 can indeed eliminate the problem of false rising or falling edges caused by CP insertion. However, this approach ignores the fact that the change in the M value occurs at the transmitter (reader). The receiver (or device) is unaware of the change in the M value, which may affect its clock synchronization and demodulation.

[0070] In order to solve the above problems, an embodiment of the present application provides a method for obtaining information. It uses the principle that the duration of the OFDM symbol remains unchanged. After the M value is changed, the number of sampling points for different level states at the receiving end will change, and the duration corresponding to the different level states will also change accordingly. A scheme is designed for the receiving end to calculate the changed M value based on the actual number of sampling points or the actual chip duration. After the M value is changed, the receiving end can synchronously obtain the changed M value, thereby avoiding problems such as clock synchronization and demodulation at the receiving end caused by the change in the M value, thereby improving the communication quality between the transmitting end and the receiving end in the R2D scenario.

[0071] like Figure 5A For ease of understanding, when the M value does not change, the duration of a single OFDM symbol chip (chip duration) is recorded as the standard chip duration. After the M value changes, the chip duration actually obtained by the receiver is recorded as the actual chip duration, and express.

[0072] In the A-lot standard discussion, a standard chip duration It is defined as M equal parts of the OFDM symbol duration excluding the CP, which can be calculated using formula (1-1):

[0073] (1-1)

[0074] in, is the duration of the OFDM symbol excluding the CP part, and M is the number of chips in the OFDM symbol.

[0075] It should be understood that the receiving end cannot directly distinguish the boundary between two consecutive chips in the same level state. Usually, the actual chip duration is determined based on the rising edge or falling edge. Therefore, when the M value does not change, the actual chip duration obtained by the receiving end includes four situations: (1) ; (2) ; (3) ; (4) .in, is the duration of the OFDM symbol CP. When the M value changes, the duration of the OFDM symbol remains unchanged, and the actual chip duration obtained by the receiver will change compared to the duration in the above four situations, resulting in the actual chip duration no longer meeting the duration in the above four situations. Therefore, the duration in the above four situations can be used as a benchmark to determine whether the M value has changed. For the sake of convenience, the following will be 、 、 、 Collectively referred to as benchmark chip duration.

[0076] Among them, if the actual chip duration If the chip duration meets a certain benchmark, it is considered It is a normal value. At this time, it is impossible to determine whether the M value has changed. If the actual chip duration If it does not meet any benchmark chip duration, it is considered For outliers, it can be determined that the M value has changed.

[0077] In some embodiments, the standard chip duration after the M value is changed is recorded as , which is the time duration of the OFDM symbol divided into (M±1) equal parts. It can be calculated using formula (1-2) :

[0078] (1-2)

[0079] In some embodiments, after the value of M is changed, the actual duration of the first chip corresponding to the OFDM symbol n obtained by the receiving end is: , that is , here The duration of the last chip of OFDM symbol (n-1).

[0080] Generally speaking, after M is changed, the actual chip duration obtained by the receiver is different from the benchmark chip duration. For example, see Figure 5B , taking the OFDM symbol n M value changed to (M-1) as an example, the standard chip duration after the M value is changed Greater than the standard chip duration when the M value remains unchanged , so the relationship between the first actual chip duration of OFDM symbol n obtained by the receiver and the reference chip satisfies: ,Right now , that is to say Or, in some special cases, after the M value is changed, the first actual chip duration obtained by the receiving end just meets a certain benchmark chip duration, but the next actual chip duration in this case must be different from the benchmark chip duration. Based on this, the embodiment of the present application can be Compare this with the benchmark chip duration to determine whether the M value has changed. If so, reverse the relationship and determine the changed M value.

[0081] The following describes the specific methods for determining the changed M value under different comparison results.

[0082] Comparison result A: .

[0083] Depend on It can be inferred The duration is different from the benchmark chip duration, and the M value is changed.

[0084] Further, by It can be inferred ,Right now , which means that the standard chip duration after M is changed becomes longer than when the M value is unchanged. In reverse, it can be seen that the M value corresponding to the OFDM symbol becomes smaller at this time, and the M value is changed to (M-1).

[0085] In one implementation, the receiving end can pre-acquire the specific value of M. After determining that the value of M has been changed to (M-1), the receiving end can obtain the changed value based on the known value of M. For example, the transmitting end can send the specific value of M to the receiving end via a preamble when establishing communication or performing clock synchronization with the receiving end. Alternatively, the receiving end can pre-acquire the specific value of M according to protocol specifications.

[0086] In another implementation, the receiving end may also calculate the changed M value using the following formula (1-3):

[0087] (1-3)

[0088] in, It can be a value specified by the protocol, such as ; The actual chip duration of the first OFDM symbol n after the M value is changed can be obtained by the receiver by calculating the number of sampling points. The value of , The standard chip duration of OFDM symbol n when the M value is unchanged. is the CP duration of OFDM symbol n.

[0089] In some embodiments, the receiving end may pre-acquire , as calculated according to formula (1-1).

[0090] In some embodiments, the receiving end may also obtain For example, the CP duration may be obtained through protocol provisions, or the CP duration may be obtained based on CP length information sent by the transmitting end. The embodiment of the present application does not limit the specific manner in which the receiving end obtains the CP duration.

[0091] Comparison result B: .

[0092] , in this case, that is, satisfying , at this time if The actual chip durations in the above four situations are different, and the receiver can distinguish is abnormal, then the following: (1) The receiving end can Calculate the changed M value; (2) The receiving end can discard the , according to the next actual chip duration received Get the changed M value.

[0093] For (1), similar to the calculation method in comparison result A, the receiver can calculate the changed M value using the following formula (1-4):

[0094] (1-4)

[0095] in, The actual first chip duration of OFDM symbol n after the M value is changed; , The standard chip duration of OFDM symbol n when the M value is unchanged. is the CP duration of OFDM symbol n; The standard chip duration of OFDM symbol n when the value of M is unchanged; is the CP duration of OFDM symbol n. and It can be obtained in advance by the receiving end. The acquisition method can be found in the above introduction and will not be repeated here.

[0096] It should be noted that using method (1) to calculate the modified M value is optional. In specific applications, this calculation method is applicable when the receiver can distinguish that the first actual chip duration of the OFDM symbol is abnormal, that is, different from the reference chip duration. In this case, the modified M value can be calculated using the above formula (1-4).

[0097] It should be noted that if the M value is changed, the actual chip duration of the OFDM symbol just meets , and the second actual chip duration is , the receiver will consider the first actual chip duration as a normal value and the second actual chip duration as the first abnormal value. In this case, the above formula (1-4) can no longer be used to calculate the changed M value. However, the method of obtaining the changed M value using the calculation method in (2) is feasible. In other words, the method of calculating the changed M value using the above formula (1-4) is suitable for the case where the receiver can identify that the first actual chip duration of the OFDM symbol is an abnormal value.

[0098] It should also be noted that if the receiving end does not distinguish the abnormality of the first actual chip duration, and the second actual chip duration , that is, the second actual chip duration meets the comparison result B. Then, using method (2) to calculate the changed M value, the receiver needs to obtain at least 4 chips of the OFDM symbol. That is, method (2) in this case is applicable to the case where the M value changes from 3 to 4 or above (the case of comparison result D below is a special case of the calculation method in this case).

[0099] Regarding (2), obtaining the changed M value based on the next actual chip duration can be divided into the following two situations.

[0100] Case a: Next actual chip duration .

[0101] like Figure 6A As shown, if the next actual chip duration , that is, the next actual chip duration is the duration of a standard chip after the M value is changed. At this time, It can be inferred that the M value corresponding to OFDM symbol n becomes larger, that is, the M value is changed to (M+1).

[0102] In one implementation, the receiving end can pre-acquire the specific value of M. After determining that the value of M has been changed to (M+1), the receiving end can obtain the changed value based on the known value of M. For example, the transmitting end can send the specific value of M to the receiving end via a preamble when establishing communication or performing clock synchronization with the receiving end. Alternatively, the receiving end can pre-acquire the specific value of M according to protocol specifications.

[0103] In another implementation, the receiving end can also use the following formula (1-5) based on the next actual chip duration and Calculate the changed M value:

[0104] (1-5)

[0105] in, It can be a value specified by the protocol, such as ; After the M value is changed, the actual second chip duration of OFDM symbol n can be obtained by the receiver through the number of sampling points. The value of .

[0106] Case b: Next actual chip duration .

[0107] like Figure 6B As shown, if the next actual chip duration , that is, the next actual chip duration is two standard chip durations after the M value is changed. At this time, It can be inferred that the M value corresponding to OFDM symbol n becomes larger, that is, the M value is changed to (M+1).

[0108] In one implementation, the receiving end may obtain a specific value of M in advance. After determining that the value of M is changed to (M+1), the receiving end may obtain the changed value based on the known value of M.

[0109] In another implementation, the receiving end can also use the following formula (1-6) based on the next actual chip duration and Calculate the changed M value:

[0110] (1-6)

[0111] in, It can be a value specified by the protocol, such as ; After the M value is changed, the actual second chip duration of OFDM symbol n can be obtained by the receiver through the number of sampling points. The value of .

[0112] Comparison result C: .

[0113] Different from the comparison result B above, in this case, the receiver cannot distinguish Is it abnormal? That is, in this case, after the M value is changed, The same as a benchmark chip duration. For example, Figure 6C As shown, if the M value is changed, it just satisfies , which means that one of the above four situations is satisfied , then the receiver may draw the wrong conclusion based on the comparison result that the M value has not changed. Since no abnormality is identified, the receiver can continue to obtain the next actual chip duration. , considering the change of M value, the next actual chip duration It must be abnormal and not affected by Therefore, the changed M value can be obtained according to the next actual chip duration.

[0114] The case of obtaining the changed M value according to the next actual chip duration is similar to the case in the above comparison result B and can be divided into the following two cases.

[0115] Case c: Actual chip duration of the next chip .

[0116] like Figure 6A As shown, if the next actual chip duration , that is, the next actual chip duration is the standard chip duration after the M value is changed. At this time, It can be inferred that the M value corresponding to OFDM symbol n becomes larger, that is, the M value is changed to (M+1).

[0117] In one implementation, the receiving end may obtain a specific value of M in advance. After determining that the value of M is changed to (M+1), the receiving end may obtain the changed value based on the known value of M.

[0118] In another implementation, the receiving end can also use formula (1-5) based on the next actual chip duration and Calculate the changed M value. The introduction to formulas (1-5) can be found above and will not be repeated here.

[0119] Case d: Next actual chip duration .

[0120] like Figure 6B As shown, if the next actual chip duration , that is, the next actual chip duration is two standard chip durations of the M value change, At this time, It can be inferred that the M value corresponding to OFDM symbol n becomes larger, that is, the M value is changed to (M+1).

[0121] In one implementation, the receiving end may obtain a specific value of M in advance, and the receiving end may obtain the changed value based on the known M value.

[0122] In another implementation, the receiving end can also use formula (1-6) based on the next actual chip duration and Calculate the changed M value. The introduction to formula (1-6) can be found above and will not be repeated here.

[0123] Comparison result D: When the initial value of M is 2, .

[0124] It should be noted that 3GPP The value of has been specified. or In addition, in this scenario When the initial value of M is 2, if (That is, theoretically consistent with the above comparison result C), then based on and There must be a specific value of , the receiver can now distinguish Therefore, this situation is essentially the same as that in the aforementioned comparison result B. Therefore, the modified M value is calculated not by the method in the aforementioned comparison result C, but by the method in the aforementioned comparison result B as a special case.

[0125] According to the information acquisition method provided in the embodiment of the present application, the receiving end determines the changed M value based on the actual chip duration of the OFDM symbol, so that the receiving end can synchronously obtain the accurate M value even when the transmitting end changes the M value and does not indicate it to the transmitting end, thereby avoiding the impact of the change in the M value on the clock synchronization, demodulation, etc. of the receiving end, and improving the communication quality.

[0126] It is understandable that if the receiving end can directly obtain the actual chip duration of OFDM symbol n (e.g., by monitoring the duration of different level states in the OFDM symbol), then the modified M value can be obtained according to the method provided in the above embodiment. However, in actual applications, the receiving end generally does not directly monitor the chip duration, but instead indirectly obtains the chip duration through the number of sampling points and the relationship between the number of sampling points and the sampling duration. Therefore, to increase the universality of the solution, the information acquisition method provided in the embodiment of the present application can further rewrite the above method to design another solution for determining the M value based on the sampling points.

[0127] For ease of description, the following embodiments record the number of sampling points corresponding to OFDM symbol n as , the number of sampling points corresponding to the CP of the OFDM symbol n is recorded as , The corresponding number of sampling points is recorded as , The corresponding number of sampling points is recorded as , the above benchmark chip duration 、 、 and The corresponding number of sampling points is recorded as 、 、 and The number of sampling points and duration are directly proportional ( ,in is the sampling duration, f is the sampling frequency), so we can also use the method of judging whether the M value has changed by the benchmark chip duration to calculate the number of sampling points. 、 、 and It is used as a benchmark to determine whether the M value has changed, and is referred to as the benchmark sampling point number below.

[0128] In some embodiments, the receiving end samples the OFDM symbol to obtain the actual number of sampling points corresponding to different level states. After that, the receiving end can Compare this with the number of baseline sampling points to determine if the M value has changed. If so, reverse the relationship and determine the changed M value.

[0129] Among them, if the actual number of sampling points If the number of sampling points meets a certain benchmark, it is considered that the is a normal value, and it is impossible to tell that the M value has changed; if the actual number of sampling points If any of the benchmark sampling points are not met, the is an outlier, and the M value changes.

[0130] The following describes the specific methods for determining the changed M value under different comparison results.

[0131] Comparison result E: .

[0132] This situation corresponds to the comparison result A mentioned above, so formula (1-3) can be rewritten to obtain the M value calculation formula based on the number of sampling points.

[0133] when When .Will Substituting the relationship between the number of sampling points and the sampling duration into formula (1-4), we can obtain formula (1-7):

[0134] (1-7)

[0135] in, is the number of sampling points corresponding to the OFDM symbol, which can be calculated based on the OFDM duration and sampling frequency.

[0136] In some embodiments, the receiving end may pre-acquire For example, after M is changed, the receiver can obtain the value of For example, the receiving end can also obtain the value of and ,according to Get The value of .

[0137] Comparison result F: .

[0138] In this case, if The number of sampling points is different from the baseline, and the receiver can tell that the M value has changed. Then: (1) The receiver can Calculate the changed M value; (2) The receiving end can continue sampling according to the next actual sampling number Determine the changed M value.

[0139] Regarding (1), the calculation method is similar to that in comparison result E and will not be repeated here.

[0140] For (2), according to the next actual sampling number Determining the changed M value can be divided into the following two situations.

[0141] Case a: The next actual number of sampling points .

[0142] The next actual number of sampling points is the standard number of sampling points after the M value is changed. At this point, the changed M value can be determined by the following formula (1-8):

[0143] (1-8)

[0144] in, is the number of sampling points corresponding to the OFDM symbol, which can be calculated based on the OFDM duration and sampling frequency; is the actual number of sampling points corresponding to the next level state, that is, the actual number of sampling points corresponding to the second level state of OFDM symbol n.

[0145] Case b: The next actual sampling number .

[0146] The next actual number of sampling points is the number of two standard sampling points after the M value is changed. At this point, the changed M value can be determined by the following formula (1-9):

[0147] (1-9)

[0148] in, is the number of sampling points corresponding to the OFDM symbol, which can be calculated based on the OFDM duration and sampling frequency; is the actual number of sampling points corresponding to the next level state, that is, the actual number of sampling points corresponding to the second level state of OFDM symbol n.

[0149] Comparison result G: .

[0150] The difference from the above comparison result F is that in this case, even if the value of M changes, It may also be the same as one of the reference sampling points, in which case the receiver cannot distinguish There are exceptions. For example, if the M value is changed , but just satisfying (or ), then the receiver may be based on The comparison result with the number of benchmark sampling points leads to the wrong conclusion that the M value has not changed. Considering that the next actual number of sampling points after the M value changes It must be abnormal, so the number of actual sampling points can be Determine the changed M value.

[0151] Among them, according to the number of actual sampling points next The situation of determining the changed M value is similar to situation a and situation b described in the above comparison result F. For details, please refer to the above introduction and will not be repeated here.

[0152] Comparison result H:M initial value is 2, .

[0153] It should be noted that 3GPP has no specific requirements for the scenarios in which the embodiments of this application are applicable. The value of has been specified. or In addition, in this scenario When the initial value of M is 2, if , then based on the above and There must be a specific value of , the receiver can now distinguish is abnormal. At this time, the receiving end can continue sampling according to the actual number of samples corresponding to the next level state. Determine the changed M value.

[0154] Among them, the actual number of sampling points corresponding to the next level state The situation of determining the changed M value is the same as situation a and situation b described in the above situation F. For details, please refer to the above introduction and will not be repeated here.

[0155] According to the method for determining communication information provided in an embodiment of the present application, the receiving end determines the changed M value based on the number of sampling points for different level states of the OFDM symbol, so that the receiving end can synchronously obtain the accurate M value even when the transmitting end changes the M value and does not indicate it to the transmitting end, thereby avoiding the impact of the change in the M value on the clock synchronization, demodulation, etc. of the receiving end, and improving the communication quality.

[0156] In order to better understand the method for determining communication information provided in the embodiment of the present application, the solution of the present application is introduced below with reference to more specific examples.

[0157] Taking the initial M value of OFDM symbol n as 4 as an example, assuming the sampling rate , , , then the number of benchmark sampling points 、 、 and They can be calculated as follows:

[0158] ;

[0159] ;

[0160] ;

[0161] .

[0162] Example 1: The transmitter changes the M value of the OFDM symbol to 3 (that is, M is changed to M-1).

[0163] The actual number of sampling points for OFDM symbols at the receiver is 84 or 85. The actual number of sampling points can be determined by the receiving end based on the actual sampling situation. For ease of understanding, the following theoretical verification of the actual number of sampling points is based on the value of the changed M value.

[0164] The actual number of sampling points satisfies the formula ,in, The standard chip duration corresponding to the last chip of OFDM symbol (n-1) is is the chip duration corresponding to the CP of OFDM symbol n, The actual chip duration corresponding to the first chip of OFDM symbol n.

[0165] in:

[0166] ;

[0167] ;

[0168] ;

[0169] .

[0170] when The value of hour, It is 84.

[0171] Since 84 or 85 is greater than 74 (or 75), the current example satisfies , at this time, the changed M value can be determined using formula (1-7), that is:

[0172] ;

[0173] or,

[0174] ;

[0175] or,

[0176] ;

[0177] or,

[0178] .

[0179] That is, and For different possible values, the changed M value calculated by formula (1-7) falls within the range of 2.98~3.12. Rounding the M value, the changed M value is 3.

[0180] Optionally, the receiver can also obtain the corresponding actual chip duration based on the actual number of sampling points in this example. or, according to 、 、 Get the corresponding actual chip duration After calculation, The value of .

[0181] because The duration is different from the benchmark chip and meets At this time, the changed M value can be determined using formula (1-3), and the changed M value is 3.

[0182] Example 2: The transmitter changes the M value of OFDM symbol n to 5 (that is, M is changed to M+1).

[0183] The actual number of sampling points for OFDM symbol n at the receiver The actual number of sampling points can be determined by the receiver based on the actual sampling situation. For ease of understanding, the following theoretical verification of the actual number of sampling points is based on the changed value of M.

[0184] The actual number of sampling points satisfies the formula ,in, The standard chip duration corresponding to the last chip of OFDM symbol (n-1) is is the chip duration corresponding to the CP of OFDM symbol n, The actual chip duration corresponding to the first chip of OFDM symbol n.

[0185] in:

[0186] ;

[0187] ;

[0188] .

[0189] Will 、 and The specific value of , we can conclude that the actual number of sampling points is 68. The value of hour, It is 67.

[0190] Due to the actual number of sampling points and So in actual scenarios, the receiver may not be able to distinguish the actual number of sampling points from The difference between The number of sampling points that meet the benchmark , and conclude that M has not changed.

[0191] On this basis, the receiving end can continue to sample the signal corresponding to the next level state in OFDM symbol n, and divide it into the following two situations according to the sampling results.

[0192] Case a: The actual number of sampling points is 25 or 26.

[0193] At this point, it can be concluded 13.3 , The value of M after the change can be determined according to the following formula:

[0194] ;

[0195] or

[0196] .

[0197] That is, Under different possible values, the calculated changed M value falls within the range of 4.92~5.12. Rounding the M value, the changed M value is 5, which is consistent with the actual situation.

[0198] Case b: The actual number of sampling points is 51 or 52.

[0199] At this point, it can be concluded for , The value of M after the change can be determined according to the following formula:

[0200] ;

[0201] or,

[0202] .

[0203] That is, Under different possible values, the calculated changed M value falls within the range of 4.92~5.02. By rounding the M value, the changed M value is 5, which is consistent with the actual situation.

[0204] Optionally, the receiver can also obtain the actual number of sampling points in this example to obtain the corresponding actual chip duration. , then based on Determine the changed M value.

[0205] .

[0206] Will and The specific value of is put into the above formula to get for or .

[0207] Due to the actual chip duration and So in actual scenarios, the receiver may not be able to distinguish the actual chip duration from ( ) between the two, This is consistent with the benchmark chip duration, so we conclude that M has not changed.

[0208] On this basis, the receiving end can continue to obtain the next actual chip duration in OFDM symbol n and calculate the changed M value based on the next actual chip duration. The specific calculation process can be found in the above description and will not be repeated here.

[0209] According to the method for determining communication information provided in an embodiment of the present application, the receiving end determines the changed M value based on the number of sampling points or chip duration for different level states of the OFDM symbol, so that the receiving end can synchronously obtain the accurate M value even when the transmitting end changes the M value and does not indicate it to the transmitting end, thereby avoiding the impact of the change in the M value on the clock synchronization, demodulation, etc. of the receiving end, and improving the communication quality.

[0210] It should be noted that the above embodiment is a method for obtaining the modified M value under ideal communication conditions. In actual communication, the influence of sampling frequency offset (SFO) needs to be considered. Specifically, it can be divided into the following situations.

[0211] (1) The receiving end performs frequency correction or adopts clock synchronization and other means to eliminate SFO: In this case, the receiving end can effectively suppress the influence of frequency deviation, and the method provided in this application can be executed normally in the established manner to ensure the accuracy and stability of signal processing.

[0212] (2) The receiving end does not perform frequency correction, but the frequency deviation is relatively stable: Although the receiving end does not actively correct the frequency deviation, since the frequency deviation is relatively fixed, the number of abnormal sampling points or abnormal chip duration can still be accurately identified by comparing between sampling points. When calculating the M value based on the sampling point ratio, since the number of sampling points N is proportional to the sampling frequency, according to the characteristics of the division operation, the frequencies f cancel each other out during the calculation process and will not interfere with the accurate solution of the M value. The method provided in this application can still function normally.

[0213] (3) The receiving end does not perform frequency correction, and the frequency offset fluctuates significantly over time: Due to the lack of stability and large fluctuation range of the frequency offset, the receiving end cannot accurately determine the M value, and it will also seriously interfere with the Manchester decoding process, causing the technical solution to fail. In this case, it is necessary to consider replacing hardware with better performance, or deploying real-time digital phase-locked loops (PLLs), Kalman filters, and other devices at the receiving end to track frequency changes in real time. However, the latter two methods will significantly increase the design complexity and implementation cost of the receiving end.

[0214] For example, Figure 7FIG. 1 is a schematic flow chart of a method for obtaining information provided in an embodiment of the present application. The process can be executed by a receiving device and may include the following steps:

[0215] S701: Obtain the number of sampling points for an OFDM symbol.

[0216] S702: Obtain a changed M value of the OFDM symbol according to the number of sampling points. The M value is used to indicate the number of chips included in the OFDM symbol.

[0217] In some embodiments, the method further includes: obtaining the total number of sampling points for the OFDM symbol , the number of sampling points of the cyclic prefix CP of the OFDM symbol , Number of first standard sampling points One or more of the following, the number of the first standard sampling points The number of sampling points corresponding to the standard chip duration of the OFDM symbol when the M value is unchanged; the number of sampling points corresponding to the OFDM symbol , the number of sampling points corresponding to the cyclic prefix CP of the OFDM symbol , the number of first standard sampling points One or more of the items in the table are related to the actual number of sampling points. Get the M value after the OFDM symbol is changed, the actual number of sampling points is the number of sampling points corresponding to different level states of the OFDM symbol.

[0218] In some embodiments, the method further comprises: according to the number of sampling points corresponding to the cyclic prefix CP of the OFDM symbol , Number of first standard sampling points Obtain the number of reference sampling points, wherein the number of reference sampling points includes obtaining the first number of reference sampling points , the number of the second benchmark sampling points , the number of the third benchmark sampling points , the number of the fourth benchmark sampling points ; Wherein, the number of the first reference sampling points is the number of the first standard sampling points The number of the second reference sampling points is twice the number of the first standard sampling points The third reference sampling point number is the number of sampling points corresponding to the cyclic prefix of the OFDM symbol. and the first standard number of sampling points The fourth reference sampling point number is the number of sampling points corresponding to the cyclic prefix of the OFDM symbol. and the first two standard sampling point numbers sum.

[0219] In some embodiments, the method further comprises: The relationship between the number of reference sampling points and the number of reference sampling points is used to obtain the M value of the OFDM symbol after the change.

[0220] In some embodiments, the method further comprises: when the When , the changed M value is calculated according to the following formula:

[0221] ;

[0222] When satisfied When the actual number of next sampling points is obtained ;in:

[0223] If satisfied , the changed M value is calculated by the following formula:

[0224] ;

[0225] If satisfied , the changed M value is calculated using the following formula:

[0226] .

[0227] In some embodiments, the When the actual number of next sampling points is obtained , specifically including: when meeting When the If the number of sampling points is different from the reference sampling points, it will be discarded. , get the next actual sampling point number ; or, when satisfied When the If the number of actual sampling points is the same as one of the reference sampling points, the actual number of sampling points corresponding to the next level state is obtained. ; or, when satisfied When the initial value of M is 2, and the If the number of sampling points is different from the reference sampling points, it will be discarded. , get the actual number of sampling points corresponding to the next level state .

[0228] In some embodiments, the method further includes: obtaining the M value when it is unchanged.

[0229] In some embodiments, the changed M value is M+1 or M-1, and the method further includes: when the When the changed M value is M+1, or when the When the actual number of next sampling points is obtained ; Among them: if satisfied , obtain the changed M value as M+1; if , obtain the changed M value as M-1; and obtain the value of M+1 or the value of M-1 according to the unchanged M value.

[0230] In some embodiments, obtaining the unchanged M value specifically includes: receiving M value indication information sent by the transmitting end; and obtaining the unchanged M value according to the M value indication information.

[0231] In some embodiments, obtaining the changed M value of the OFDM symbol according to the number of sampling points specifically includes: obtaining the actual chip duration corresponding to the OFDM symbol according to the number of sampling points , the actual chip duration The duration corresponding to different level states in the OFDM symbol; according to the actual chip duration Obtain the changed M value of the OFDM symbol.

[0232] In some embodiments, the method further comprises: according to the duration of the OFDM symbol and the M value when it is unchanged, to obtain the first standard chip duration , the first standard chip duration The duration of one chip in the OFDM symbol when the M value is unchanged; the duration of the chip according to the first standard and the duration of the cyclic prefix CP of the OFDM symbol Get the benchmark chip duration, which includes the first benchmark chip duration , Second benchmark chip duration , the third benchmark chip duration , the fourth benchmark chip duration ; Among them, the first benchmark chip duration The first standard chip duration , the second benchmark chip duration The duration of the two first standard chips The sum of the third benchmark chip duration The duration corresponding to the cyclic prefix CP of the OFDM symbol and the first standard chip duration The sum of the fourth benchmark chip duration The duration corresponding to the cyclic prefix CP of the OFDM symbol and the duration of the first two standard chips sum.

[0233] In some embodiments, the method further comprises: when the When , the changed M value is calculated according to the following formula:

[0234] ;

[0235] When satisfied Get the next actual chip duration ;in:

[0236] If satisfied , the changed M value is calculated using the following formula:

[0237] ;

[0238] If satisfied , the changed M value is calculated by the following formula:

[0239] .

[0240] In some embodiments, the Get the next actual chip duration , specifically including: when meeting When the If the chip duration is different from the benchmark chip duration, it will be discarded. , get the next actual chip duration ; or, when satisfied When the If it is the same as one of the benchmark chip durations, the next actual chip duration is obtained. ; or, when satisfied When the initial value of M is 2, and the If the chip duration is different from the benchmark chip duration, it will be discarded. , get the next actual chip duration .

[0241] In some embodiments, the method further includes: obtaining the M value when it is unchanged.

[0242] In some embodiments, the changed M value is M+1 or M-1, and the method further includes: when the When the changed M value is M+1, or when the Get the next actual chip duration ; Among them: if satisfied , obtain the changed M value as M+1; if , obtain the changed M value as M-1; and obtain the value of M+1 or the value of M-1 according to the unchanged M value.

[0243] In some embodiments, obtaining the unchanged M value specifically includes: receiving M value indication information sent by the transmitting end; and obtaining the unchanged M value according to the M value indication information.

[0244] In some embodiments, the encoding method corresponding to the OFDM symbol is Manchester encoding.

[0245] According to the information acquisition method provided in the embodiment of the present application, by utilizing the principle that the duration of the OFDM symbol remains unchanged, the number of sampling points for different level states at the receiving end will change after the M value is changed, and the duration corresponding to the different level states will also change accordingly, a scheme is designed for the receiving end to calculate the changed M value based on the actual number of sampling points or the actual chip duration, so that after the M value is changed, the receiving end can synchronously obtain the changed M value, thereby avoiding problems such as clock synchronization and demodulation at the receiving end caused by the change in the M value, and improving the communication quality between the transmitting end and the receiving end in the R2D scenario.

[0246] The technical solution provided in this application can be applied to the R2D scenario in the A-IoT system, or can also be applied to other low-traffic communication scenarios.

[0247] The technical solutions provided in this application can be applied to various communication systems, such as: global system for mobile communications (GSM) system, general packet radio service (GPRS), wireless local area network (WLAN), long term evolution (LTE) system, LTE frequency division duplex (FDD) system, LTE time division duplex (TDD) system, sidelink communication system, universal mobile telecommunication system (UMTS), worldwide interoperability for microwave access (WiMAX) communication system, non-terrestrial network (NTN) communication system, fifth generation (5G) mobile communication system or new radio access technology (NR). Among them, 5G mobile communication system can include non-standalone (NSA) and / or standalone (SA) networking. The technical solutions provided in this application can also be applied to future communication systems. This application is not limited to this.

[0248] Figure 8 FIG1 is a schematic diagram of a wireless communication system 10 used in an embodiment of the present application. The wireless communication system 10 may include a transmitter and a receiver.

[0249] The transmitting end in this application may also be referred to as a reader end or reader end. For example, the transmitting end can be a device installed in a specific location and used to batch read information from the receiving end; alternatively, the transmitting end can be a handheld reader, a vehicle-mounted reader, or an industrial-grade reader. The transmitting end can also be a network-side device such as an access network or core network device. Access network devices are sometimes also referred to as access nodes. Access network devices have wireless transceiver functions and are used to communicate with terminals. Access network devices include, but are not limited to, base stations (base stations), evolved NodeBs (eNodeBs), transmission reception points (TRPs) in the above-mentioned communication systems, next-generation NodeBs (gNBs) in 5G mobile communication systems, access network devices or modules of access network devices in open access networks (ORAN) systems, satellites in NTN communication systems, base stations in future mobile communication systems, or access nodes in WiFi systems. Access network devices can also be modules or units that can implement some of the functions of a base station. The access network device can be a macro base station, a micro base station or an indoor station, a relay node or a donor node, or a wireless controller in a cloud radio access network (CRAN) scenario. Optionally, the access network device can also be a server, a wearable device, or an on-board device. For example, the access network device in the vehicle to everything (V2X) technology can be a road side unit (RSU). Multiple access network devices in a communication system can be base stations of the same type or different types. A base station can communicate with a terminal or communicate with a terminal through a relay station. A terminal can communicate with multiple base stations in different access technologies. The embodiments of the present application do not limit the specific technology and specific device form adopted by the access network device. In the present application, the access network device is referred to as a network device.

[0250] The receiving end in the embodiments of the present application may also be referred to as a device end or device end. The receiving end may be, for example, a smart sensor, smart tag, smart home appliance, wearable device, etc. The receiving end can be widely used in various low-rate communication scenarios, such as device-to-device (D2D), vehicle-to-everything (V2X) communication, machine-type communication (MTC), Internet of Things (IoT), ultra-reliable low-latency communication (URLLC), virtual reality, augmented reality, industrial control, autonomous driving, telemedicine, smart grid, smart furniture, smart office, smart wearable, smart transportation, smart city, or satellite communication. The terminal may be a mobile phone, tablet computer, computer with wireless transceiver capabilities, wearable device, vehicle, aircraft (such as drones, helicopters, airplanes), hot air balloon, ship, robot, robotic arm, or smart home appliance. The embodiments of the present application do not limit the form of the terminal device.

[0251] In this application, the device for implementing the function of the receiving end can be a device or a device that can support the receiving end to implement the function, such as a processor, circuit, chip, chip system, etc. The device can be installed in the UE or connected to the UE for use. In the technical solution provided in this application, the technical solution provided in this application is described by taking the device for implementing the function of the UE as an example.

[0252] For example, Figure 9 , which is a schematic structural diagram of an electronic device 100 provided in an embodiment of the present application. The electronic device may correspond to the client and / or server in the present application.

[0253] It should be noted that Figure 9 The structure of the electronic device 100 shown in the embodiment is only an example. In actual applications, the electronic device 100 may have more or fewer components, and the embodiment of the present application is not limited to this.

[0254] The electronic device may include a processor 110, a universal serial bus (USB) 120, a mobile communication module 130, a sensor 140, a display screen 150, etc. The sensor 140 may include a temperature sensor, a humidity sensor, a pressure sensor, a gyroscope sensor, an air pressure sensor, a magnetic sensor, an acceleration sensor, a distance sensor, a proximity light sensor, a fingerprint sensor, a temperature sensor, a touch sensor, an ambient light sensor, a bone conduction sensor, etc.

[0255] It is understood that the structures illustrated in the embodiments of the present invention do not constitute specific limitations on the electronic device. In other embodiments of the present application, the electronic device may include more or fewer components than shown, or may combine or separate certain components, or arrange the components differently. The illustrated components may be implemented in hardware, software, or a combination of software and hardware.

[0256] The processor 110 may include one or more processing units. For example, the processor 110 may include an application processor (AP), a modem processor, a graphics processing unit (GPU), an image signal processor (ISP), a controller, a memory, a video codec, a digital signal processor (DSP), a baseband processor, and / or a neural-network processing unit (NPU). The different processing units may be independent devices or integrated into one or more processors.

[0257] The controller can be the nerve center and command center of the electronic device. The controller can generate operation control signals based on instruction operation codes and timing signals to complete the control of instruction fetching and execution.

[0258] Processor 110 may also include a memory for storing instructions and data. In some embodiments, the memory in processor 110 is a cache memory. This memory can store instructions or data that have just been used or are being recycled by processor 110. If processor 110 needs to use the same instruction or data again, it can directly access the memory. This avoids duplicate accesses, reduces processor 110 latency, and thus improves system efficiency.

[0259] In some embodiments, the processor 110 may include one or more interfaces. The interfaces may include an inter-integrated circuit (I2C) interface, an inter-integrated circuit sound (I2S) interface, a pulse code modulation (PCM) interface, a universal asynchronous receiver / transmitter (UART) interface, a mobile industry processor interface (MIPI), a general-purpose input / output (GPIO) interface, a subscriber identity module (SIM) interface, and / or a universal serial bus (USB) interface.

[0260] It is understood that the interface connection relationship between the modules illustrated in the embodiments of the present invention is only a schematic illustration and does not constitute a structural limitation of the electronic device. In other embodiments of the present application, the electronic device may also adopt different interface connection methods in the above embodiments, or a combination of multiple interface connection methods.

[0261] The mobile communication module 130 can provide solutions for wireless communications, including 2G / 3G / 4G / 5G, applied on the receiving end. The mobile communication module 130 can include at least one filter, a switch, a power amplifier, a low-noise amplifier (LNA), etc. The mobile communication module 150 can receive electromagnetic waves via an antenna, filter, amplify, and perform other processing on the received electromagnetic waves, and transmit them to a modem processor for demodulation. The mobile communication module 130 can also amplify the signals modulated by the modem processor and convert them into electromagnetic waves for radiation via the antenna. In some embodiments, at least some of the functional modules of the mobile communication module 130 can be provided in the processor 110. In some embodiments, at least some of the functional modules of the mobile communication module 130 can be provided in the same device as at least some of the modules of the processor 110.

[0262] For example, Figure 10 FIG. 1 is a schematic structural diagram of a receiving end 1000 provided in an embodiment of the present application. The receiving end 1000 includes a sampling module 1001 and a processing module 1002 .

[0263] In some embodiments, the sampling module is configured to obtain the number of sampling points for the OFDM symbol;

[0264] The processing module is used to obtain the changed M value of the OFDM symbol according to the number of sampling points, and the M value is used to indicate the number of chips included in the OFDM symbol.

[0265] In some embodiments, the sampling module is further configured to obtain the total number of sampling points for the OFDM symbol. , the number of sampling points of the cyclic prefix CP of the OFDM symbol , Number of first standard sampling points One or more of the following, the number of the first standard sampling points is the number of sampling points corresponding to the standard chip duration of the OFDM symbol when the M value is unchanged;

[0266] The processing module is further configured to process the OFDM symbols according to the number of sampling points corresponding to the OFDM symbols. , the number of sampling points corresponding to the cyclic prefix CP of the OFDM symbol , Number of first standard sampling points One or more of the items in the table are related to the actual number of sampling points. Get the M value after the OFDM symbol is changed, the actual number of sampling points is the number of sampling points corresponding to different level states of the OFDM symbol.

[0267] In some embodiments, the processing module is further configured to calculate the number of sampling points corresponding to the cyclic prefix CP of the OFDM symbol. , Number of first standard sampling points Obtain the number of reference sampling points, wherein the number of reference sampling points includes obtaining the first number of reference sampling points , the number of the second benchmark sampling points , the number of the third benchmark sampling points , the number of the fourth benchmark sampling points ; Wherein, the number of the first reference sampling points is the number of the first standard sampling points The number of the second reference sampling points is twice the number of the first standard sampling points The third reference sampling point number is the number of sampling points corresponding to the cyclic prefix of the OFDM symbol. and the first standard number of sampling points The fourth reference sampling point number is the number of sampling points corresponding to the cyclic prefix of the OFDM symbol. and the first two standard sampling point numbers sum.

[0268] In some embodiments, the processing module is further configured to: The relationship between the number of reference sampling points and the number of reference sampling points is used to obtain the M value of the OFDM symbol after the change.

[0269] In some embodiments, the processing module is further configured to: When , the changed M value is calculated according to the following formula:

[0270] ;

[0271] When satisfied When the actual number of next sampling points is obtained ;in:

[0272] If satisfied , the changed M value is calculated by the following formula:

[0273] ;

[0274] If satisfied , the changed M value is calculated by the following formula:

[0275] .

[0276] In some embodiments, the processing module is further configured to: When the If the number of sampling points is different from the reference sampling points, it will be discarded. , get the next actual sampling point number ; or, when satisfied When the If the number of actual sampling points is the same as one of the reference sampling points, the actual number of sampling points corresponding to the next level state is obtained. ; or, when satisfied When the initial value of M is 2, and the If the number of sampling points is different from the reference sampling points, it will be discarded. , get the actual number of sampling points corresponding to the next level state .

[0277] In some embodiments, the processing module is further configured to obtain the M value when it is unchanged.

[0278] In some embodiments, the processing module is further configured to: When the changed M value is M+1, or when the When the actual number of next sampling points is obtained ; Among them: if satisfied , obtain the changed M value as M+1; if , obtain the changed M value as M-1; and obtain the value of M+1 or the value of M-1 according to the unchanged M value.

[0279] In some embodiments, the receiving end further includes a communication module, which is used to receive M value indication information sent by the transmitting end; the processing module is also used to obtain the unchanged M value based on the M value indication information.

[0280] In some embodiments, the processing module is further configured to obtain the actual chip duration corresponding to the OFDM symbol according to the number of sampling points. , the actual chip duration The duration corresponding to different level states in the OFDM symbol; according to the actual chip duration Obtain the changed M value of the OFDM symbol.

[0281] In some embodiments, the processing module is further configured to: and the M value when it is unchanged, to obtain the first standard chip duration , the first standard chip duration The duration of one chip in the OFDM symbol when the M value is unchanged; the duration of the chip according to the first standard and the duration of the cyclic prefix CP of the OFDM symbol Get the benchmark chip duration, which includes the first benchmark chip duration , Second benchmark chip duration , the third benchmark chip duration , the fourth benchmark chip duration ; Among them, the first benchmark chip duration The first standard chip duration , the second benchmark chip duration The duration of the two first standard chips The sum of the third benchmark chip duration The duration corresponding to the cyclic prefix CP of the OFDM symbol and the first standard chip duration The sum of the fourth benchmark chip duration The duration corresponding to the cyclic prefix CP of the OFDM symbol and the duration of the first two standard chips sum.

[0282] In some embodiments, the processing module is further configured to: When , the changed M value is calculated according to the following formula:

[0283] ;

[0284] When satisfied Get the next actual chip duration ;in:

[0285] If satisfied , the changed M value is calculated using the following formula:

[0286] ;

[0287] If satisfied , the changed M value is calculated using the following formula:

[0288] .

[0289] In some embodiments, the processing module is further configured to: When the If the chip duration is different from the benchmark chip duration, it will be discarded. , get the next actual chip duration ; or, when satisfied When the If it is the same as one of the benchmark chip durations, the next actual chip duration is obtained. ; or, when satisfied When the initial value of M is 2, and the If the chip duration is different from the benchmark chip duration, it will be discarded. , get the next actual chip duration .

[0290] In some embodiments, the processing module is further configured to obtain the M value when it is unchanged.

[0291] In some embodiments, the processing module is further configured to: When the changed M value is M+1, or when the Get the next actual chip duration ; Among them: if satisfied , obtain the changed M value as M+1; if , obtain the changed M value as M-1; and obtain the value of M+1 or the value of M-1 according to the unchanged M value.

[0292] In some embodiments, the communication module is further configured to receive M value indication information sent by the transmitting end; and obtain the unchanged M value according to the M value indication information.

[0293] Based on the same technical concept, an embodiment of the present application also provides an electronic device, including a processor; a memory; the memory stores a computer program, and the computer program includes instructions. When the instructions are executed by the processor, the electronic device performs one or more steps in any of the above methods.

[0294] Based on the same technical concept, an embodiment of the present application also provides a communication system, including a transmitting end and a receiving end, and the receiving end can execute one or more steps in any of the above methods respectively used for the receiving end to execute.

[0295] Based on the same technical concept, an embodiment of the present application also provides a chip system, which includes: a processing circuit, a receiving pin and a transmitting pin; wherein, the receiving pin, the transmitting pin and the processing circuit communicate with each other through an internal connection path, and the processing circuit executes one or more steps in any of the above methods to control the receiving pin to receive signals and control the transmitting pin to send signals.

[0296] Based on the same technical concept, an embodiment of the present application also provides a computer-readable storage medium, which stores computer-executable program instructions. When the computer-executable program instructions are executed on a computer, the computer or processor executes one or more steps in any of the above methods.

[0297] Based on the same technical concept, an embodiment of the present application also provides a computer program product containing instructions, wherein the computer program product includes computer program code. When the computer program code is run on a computer, the computer or processor executes one or more steps in any of the above methods.

[0298] In the above embodiments, all or part of the embodiments may be implemented using software, hardware, firmware, or any combination thereof. When implemented using software, all or part of the embodiments may be implemented in the form of a computer program product. The computer program product includes one or more computer instructions. When the computer instructions are loaded and executed on a computer, the processes or functions described in the embodiments of the present application are generated in whole or in part.

[0299] In the several embodiments provided in this application, it should be understood that the disclosed systems, devices and methods can be implemented in other ways. For example, the device embodiments described above are merely schematic. For example, the division of the units is merely a logical function division. In actual implementation, there may be other division methods, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0300] It should be understood that in the various embodiments of the present application, the size of the serial number of each process does not mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present application.

[0301] In short, the above description is only a preferred embodiment of the technical solution of this application and is not intended to limit the scope of protection of this application. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of this application shall be included in the scope of protection of this application.

Claims

1. A method for obtaining information, characterized in that: The method comprises: Get the number of sampling points for OFDM symbols; Acquire a changed M value of the OFDM symbol according to the number of sampling points, where the M value is used to indicate the number of chips included in the OFDM symbol; The obtaining of the changed M value of the OFDM symbol according to the number of sampling points specifically includes: Obtain the actual chip duration corresponding to the OFDM symbol according to the number of sampling points , the actual chip duration The duration corresponding to different level states in the OFDM symbol; according to the actual chip duration Obtain the changed M value of the OFDM symbol.

2. The method according to claim 1, characterized in that The method further comprises: Get the total number of sampling points for the OFDM symbol , the number of sampling points of the cyclic prefix CP of the OFDM symbol , Number of first standard sampling points One or more of the following, the number of the first standard sampling points is the number of sampling points corresponding to the standard chip duration of the OFDM symbol when the M value is unchanged; According to the number of sampling points corresponding to the OFDM symbol , the number of sampling points corresponding to the cyclic prefix CP of the OFDM symbol , the number of first standard sampling points One or more of the items in the table are related to the actual number of sampling points. Get the M value after the OFDM symbol is changed, the actual number of sampling points is the number of sampling points corresponding to different level states of the OFDM symbol.

3. The method according to claim 2, characterized in that The method further comprises: According to the number of sampling points corresponding to the cyclic prefix CP of the OFDM symbol , Number of first standard sampling points Get the number of benchmark sampling points, where The number of reference sampling points includes obtaining the number of first reference sampling points , the number of second benchmark sampling points , the number of third benchmark sampling points , the number of fourth benchmark sampling points ; Wherein, the number of the first reference sampling points is the number of the first standard sampling points The number of the second reference sampling points is twice the number of the first standard sampling points The third reference sampling point number is the number of sampling points corresponding to the cyclic prefix of the OFDM symbol. and the first standard number of sampling points The fourth reference sampling point number is the number of sampling points corresponding to the cyclic prefix of the OFDM symbol. and the first two standard sampling point numbers sum.

4. The method according to claim 3, characterized in that The method further comprises: According to the actual number of sampling points The relationship between the number of reference sampling points and the number of reference sampling points is used to obtain the M value of the OFDM symbol after the change.

5. The method according to claim 4, characterized in that The method further comprises: When satisfied When , the changed M value is calculated according to the following formula: ； When satisfied When the actual number of next sampling points is obtained ;in: If satisfied , the changed M value is calculated by the following formula: ； If satisfied , the changed M value is calculated using the following formula: 。 6. The method according to claim 5, characterized in that When the When the actual number of next sampling points is obtained , specifically including: When satisfied When the If the number of sampling points is different from the reference sampling points, it will be discarded. , get the next actual sampling point number ;or, When satisfied When the If the number of actual sampling points is the same as one of the reference sampling points, the next actual sampling point number is obtained. ;or, When satisfied When M is unchanged, the value is 2, and the If the number of sampling points is different from the reference number, it will be discarded. , get the actual number of sampling points corresponding to the next level state .

7. The method according to claim 4, characterized in that The method further comprises: Get the value of M when it is unchanged.

8. The method according to claim 7, characterized in that The changed M value is M+1 or M-1, and the method further includes: When satisfied , obtaining the changed M value as M+1; or, When satisfied When the actual number of next sampling points is obtained ;in: If satisfied , obtaining the changed M value as M+1; If satisfied , obtain the changed M value as M-1; The value of M+1 or M-1 is obtained according to the unchanged value of M.

9. The method according to claim 7 or 8, characterized in that The obtaining of the unchanged M value specifically includes: Receive M value indication information sent by the transmitter; The unchanged M value is obtained according to the M value indication information.

10. The method according to claim 1, characterized in that The method further comprises: According to the duration of the OFDM symbol and the M value when it is unchanged, to obtain the first standard chip duration , the first standard chip duration The duration corresponding to one chip in the OFDM symbol when the M value is unchanged; According to the first standard chip duration and the duration of the cyclic prefix CP of the OFDM symbol Get the benchmark chip duration, which includes the first benchmark chip duration , Second benchmark chip duration , the third benchmark chip duration , the fourth benchmark chip duration ; Among them, the first benchmark chip duration The first standard chip duration , the second benchmark chip duration The duration of the two first standard chips The sum of the third benchmark chip duration The duration corresponding to the cyclic prefix CP of the OFDM symbol and the first standard chip duration The sum of the fourth benchmark chip duration The duration corresponding to the cyclic prefix CP of the OFDM symbol and the duration of the first two standard chips sum.

11. The method according to claim 10, characterized in that The method further comprises: When satisfied When , the changed M value is calculated according to the following formula: ； When satisfied Get the next actual chip duration ;in: If satisfied , the changed M value is calculated using the following formula: ； If satisfied , the changed M value is calculated using the following formula: 。 12. The method according to claim 11, characterized in that When the Get the next actual chip duration , specifically including: When satisfied When the If the chip duration is different from the benchmark chip duration, it will be discarded. , get the next actual chip duration ;or, When satisfied When the If it is the same as one of the benchmark chip durations, the next actual chip duration is obtained. ;or, When satisfied When the initial value of M is 2, and the If the chip duration is different from the benchmark chip duration, it will be discarded. , get the next actual chip duration .

13. The method according to claim 12, characterized in that The method further comprises: Get the value of M when it is unchanged.

14. The method according to claim 13, characterized in that The changed M value is M+1 or M-1, and the method further includes: When satisfied , obtaining the changed M value as M+1; or, When satisfied Get the next actual chip duration ;in: If satisfied , obtaining the changed M value as M+1; If satisfied , obtain the changed M value as M-1; The value of M+1 or M-1 is obtained according to the unchanged value of M.

15. The method according to claim 13 or 14, characterized in that The obtaining of the unchanged M value specifically includes: Receive M value indication information sent by the transmitter; The unchanged M value is obtained according to the M value indication information.

16. The method according to claim 1 or 2, characterized in that The encoding method corresponding to the OFDM symbol is Manchester encoding.

17. An electronic device, characterized in that: include: processor; Memory; The memory stores a computer program, which includes instructions. When the instructions are executed by the processor, the electronic device performs the method according to any one of claims 1 to 16.

18. A computer-readable storage medium, characterized in that The computer-readable storage medium stores computer-executable program instructions, which, when executed on a computer, enable the computer to perform the method according to any one of claims 1 to 16.

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