Data transmission method, communication device, and storage medium

Abstract

Embodiments of the present disclosure provide a data transmission method, a communication device, and a storage medium. The method comprises: obtaining a first pilot sequence; generating a first data symbol, wherein the first data symbol is obtained by encoding and modulating, using a spreading sequence, first data to be sent; and sending a first symbol sequence, wherein the first symbol sequence is composed of the first pilot sequence and the first data symbol.

Description

Data transmission method, communication apparatus, and storage medium

[0001] The present disclosure claims priority to Chinese Patent Application No. 202411104656.8, filed on August 12, 2024, the entire contents of which are incorporated herein by reference. TECHNICAL FIELD

[0002] The present disclosure relates to the field of communication technology, and in particular to a data transmission method, a communication apparatus, and a storage medium. BACKGROUND

[0003] 6G (6 th The sixth generation mobile communication technology (6G) has higher requirements for connection density and proposes a massive communication scenario, with a huge number of potential access terminals, and the traditional access scheme is difficult to meet this massive connection scenario. Therefore, grant-free transmission emerges as the times require.

[0004] In the code division multiple access grant-free transmission process, since the base station does not know which user terminals have accessed and transmitted data, the base station generally uses the orthogonality or cross-correlation between the spreading sequences to detect the spreading sequences, so as to realize the separation and analysis of the data transmitted by each user terminal. SUMMARY

[0005] In one aspect, a data transmission method is provided, applied to a first node. The data transmission method includes: obtaining a first pilot sequence; generating a first data symbol, wherein the first data symbol is obtained by encoding and modulating a first data to be transmitted using a spreading sequence; and transmitting a first symbol sequence, wherein the first symbol sequence is composed of the first pilot sequence and the first data symbol.

[0006] In another aspect, a data transmission method is provided, applied to a second node. The data transmission method includes: receiving a second symbol sequence, wherein the second symbol sequence is composed of a second pilot sequence and a second data symbol, and the second symbol sequence includes at least one first symbol sequence; pre-processing the second data symbol based on a channel estimation result to obtain a third data symbol, wherein the channel estimation result is obtained based on channel estimation of the second pilot sequence and a pilot sequence set; and performing analysis processing on the third data symbol to obtain first data of at least one first node.

[0007] In yet another aspect, a communication apparatus is provided. The communication apparatus includes an obtaining module, a generating module and a sending module. The obtaining module is configured to obtain a first pilot sequence; the generating module is configured to generate a first data symbol, wherein the first data symbol is obtained by encoding and modulating a first data to be sent using an extension sequence; and the sending module is configured to send a first symbol sequence, wherein the first symbol sequence is composed of the first pilot sequence and the first data symbol.

[0008] In yet another aspect, a communication apparatus is provided. The communication apparatus includes a receiving module and a processing module. The receiving module is configured to receive a second symbol sequence, wherein the second symbol sequence is composed of a second pilot sequence and a second data symbol, and the second symbol sequence includes at least one first symbol sequence; and the processing module is configured to pre-process the second data symbol based on a channel estimation result to obtain a third data symbol, wherein the channel estimation result is obtained based on channel estimation of the second pilot sequence and a pilot sequence set; and the processing module is further configured to parse the third data symbol to obtain first data of at least one first node.

[0009] In yet another aspect, a communication apparatus is provided. The communication apparatus includes a processor and a memory storing processor-executable instructions; wherein the processor is configured to execute the instructions, so that the communication apparatus performs the data transmission method of any one of the aspects above.

[0010] In yet another aspect, a computer-readable storage medium is provided. The computer-readable storage medium stores computer instructions, which, when executed on a communication apparatus, implement the data transmission method of any one of the aspects above.

[0011] In yet another aspect, a computer program product is provided. The computer program product includes computer instructions, which, when executed on a computer, cause the computer to perform the data transmission method of any one of the aspects above. BRIEF DESCRIPTION OF DRAWINGS

[0012] In order to more clearly illustrate the technical solutions in the present disclosure, the following will briefly introduce the drawings needed to be used in some embodiments of the present disclosure. Obviously, the drawings described in the following description are only some of the drawings of the present disclosure, and other drawings can also be obtained by those skilled in the art based on these drawings.

[0013] FIG. 1 is a schematic diagram of a system architecture of a communication system according to some embodiments of the present disclosure.

[0014] FIG. 2 is a schematic diagram of a data transmission method according to some embodiments of the present disclosure.

[0015] FIG. 3 is a schematic diagram of another data transmission method according to some embodiments of the present disclosure.

[0016] FIG. 4 is a structural schematic diagram of a communication apparatus according to some embodiments of the present disclosure.

[0017] FIG. 5 is a structural schematic diagram of another communication apparatus according to some embodiments of the present disclosure.

[0018] FIG. 6 is a structural schematic diagram of a communication apparatus according to some embodiments of the present disclosure. DETAILED DESCRIPTION

[0019] In order to enable a person skilled in the art to better understand the technical solutions of the embodiments of the present disclosure, the technical solutions in the present disclosure will be described clearly and completely below in conjunction with the drawings in the present disclosure. Obviously, the described embodiments are only some of the embodiments of the present disclosure, not all the embodiments. Based on the embodiments in the present disclosure, all other embodiments obtained by a person skilled in the art without creative work fall within the scope of protection of the present disclosure.

[0020] It should be noted that in the present disclosure, the words “exemplarily” or “for example” are used to represent as an example, illustration or description. Any embodiment or design scheme described as “exemplarily” or “for example” in the present disclosure should not be interpreted as more preferred or more advantageous than other embodiments or design schemes in the present disclosure. Rather, the words “exemplarily” or “for example” are used to present the relevant concept in a specific manner.

[0021] Hereinafter, the terms “first”, “second”, and the like are used only for descriptive purposes, and should not be construed as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined with “first”, “second”, and the like can explicitly or implicitly include one or more of the features.

[0022] In the description of the present disclosure, unless otherwise specified, the symbol “ / ” represents the relationship of “or”, for example, A / B can represent A or B. “And / or” in this document only represents a description of the association between the associated objects, which means that there can be three kinds of relationships, for example, A and / or B can represent: only A, only B, and A and B. In addition, “at least one” means one or more, and “multiple” means two or more than two.

[0023] 6G has higher requirements for connection density, proposes a massive communication scenario, and the number of potential access terminals is huge, which can reach tens of millions of terminals per square kilometer. In the traditional access and transmission scheme, the terminal first enters the connected state through random access before data transmission, and then applies for uplink transmission resources to the base station. After obtaining the grant of the base station, the information is transmitted on the uplink transmission resource authorized by the base station. In the massive connection scenario, this traditional access and transmission scheme faces problems such as large signaling overhead, high terminal power consumption, and large delay, and it is difficult to efficiently support massive terminal access. To solve this problem, unscheduled transmission emerges. In unscheduled transmission, different terminals use different code sequences or spreading sequences to transmit data, so that the base station can distinguish the data transmitted by different terminals.

[0024] Taking passive Internet of Things as an example, passive Internet of Things is a typical massive communication scenario. Considering the minimalist design of passive devices, in passive Internet of Things, a code division multiple access method based on on-off keying (OOK) waveform is generally used. This method encodes the transmission data of each terminal through a spreading sequence (also known as a spreading code), and then modulates the data to be sent onto a carrier signal through an OOK waveform and backscatters it to the base station. Due to unscheduled transmission, the base station does not know which user terminals have accessed and transmitted data, so the base station can use the orthogonality or cross-correlation between the spreading sequences to perform active user detection on the spreading sequences, so as to separate and analyze the mixed data received to obtain the transmission data of each terminal.

[0025] However, under the influence of the OOK waveform, the spreading sequence of the sending end becomes non-orthogonal or the cross-correlation becomes poor, which will affect the subsequent equalization demodulation and decoding of the data, causing the base station to be unable to correctly separate the transmission data of each user terminal, and reducing the performance of code division multiple access.

[0026] Based on this, the embodiment of the present disclosure provides a data transmission method, the sending end transmits a pilot sequence and a data symbol jointly, so that the receiving end can perform channel estimation based on the pilot symbol, and pre-process the received data symbol based on the channel estimation result, to ensure the orthogonality or cross-correlation of the spreading sequence in the received data symbol, so that the receiving end can correctly separate and analyze the data transmitted by each sending end from the received data symbol, and improve the performance of code division multiple access.

[0027] In some embodiments, the technical solutions of the present disclosure include: a first node obtains a first pilot sequence, and performs encoding processing and modulation processing on first data to be transmitted by using a spreading sequence to obtain first data symbols. Then, the first node transmits a first symbol sequence including the first pilot sequence and the first data symbols to a second node. The second node receives a second symbol sequence, pre-processes second data symbols based on a channel estimation result to obtain third data symbols, and then performs analysis processing on the third data symbols to obtain first data of the at least one first node.

[0028] It should be understood that the pilot in the embodiments of the present disclosure can be a pilot sequence, a pilot symbol, a reference signal, a preamble sequence, a preamble symbol, a random access signal, etc.

[0029] The network architecture of the communication network (including but not limited to 3G, 4G, 5G, 6G and future mobile communication networks) in the embodiments of the present disclosure can include at least one sending end (for example, including but not limited to a terminal, an Internet of Things device, etc.) and at least one receiving end (for example, including but not limited to a base station, a reader / writer, etc.).

[0030] Exemplarily, taking the sending end as at least one terminal and the receiving end as a base station as an example, FIG. 1 shows a system architecture diagram of a communication system provided by the embodiments of the present disclosure. As shown in FIG. 1, the communication system 10 includes a base station 11 and at least one terminal 12 (two terminals are taken as an example in the figure). The base station 11 and the terminal 12 can be communicatively connected. In a multiple access transmission, the terminal can perform channel coding, waveform coding, spreading code coding, modulation, etc. on first data to be transmitted to form data symbols, then map a selected pilot sequence to the data symbols and transmit to the base station, and the base station obtains the first data by processing the data symbols based on the pilot sequence.

[0031] In some embodiments, the base station 11 is configured to provide wireless access services for at least one terminal 12. For example, one base station 11 provides one service coverage area (also referred to as a cell). The terminal 12 entering the area can communicate with the base station 11 through wireless signals to accept the wireless access services provided by the base station 11. There can be overlap between the service coverage areas of the base stations 11, and the terminal 12 in the overlap area can receive wireless signals from multiple base stations 11.

[0032] In some embodiments, the base station 11 can connect multiple terminal 12 devices, for example, the base station 11 connects a first terminal 12 and a second terminal 12. The first terminal 12 and the second terminal 12 can be located in the same cell, and the first terminal 12 and the second terminal 12 can also be located in different cells. That is, one base station 11 can provide network services to the terminals 12 in one cell, and can also simultaneously provide network services to the terminals 12 in multiple cells.

[0033] In some embodiments, the base station 11 can be a base station in long term evolution (LTE), long term evolution advanced (LTEA), or an evolutional node B (eNB or eNodeB), a base station in a 5G network, or a base station in a future communication system, etc., which can include various macro base stations, micro base stations, home base stations, wireless remote devices, reconfigurable intelligent surfaces (RIS), routers, wireless fidelity (WIFI) devices, or other various network side devices involving primary cells and secondary cells, etc.

[0034] In some embodiments, the terminal 12 can be a device with wireless transceiving function, which can be deployed on land, including indoors or outdoors, handheld, wearable or vehicle-mounted; can also be deployed on water surface (such as ships, etc.); can also be deployed in the air (such as airplanes, balloons and satellites, etc.). The terminal can be a mobile phone, a tablet computer (Pad), a computer with wireless transceiving function, a virtual reality (VR) terminal, an augmented reality (AR) terminal, a wireless terminal in industrial control, a wireless terminal in self driving, a wireless terminal in remote medical, a wireless terminal in smart grid, a wireless terminal in transportation safety, a wireless terminal in smart city, a wireless terminal in smart home, etc. The embodiments of the present disclosure do not limit the application scenarios. The terminal can also be referred to as a user, a user equipment (UE), an access terminal, a UE unit, a UE station, a mobile station, a mobile station, a remote station, a remote terminal, a mobile device, a UE terminal, a wireless communication device, a UE agent or a UE apparatus, etc. The embodiments of the present disclosure do not limit this.

[0035] FIG. 2 is a flow diagram of a data transmission method provided by an embodiment of the present disclosure. Exemplarily, the data transmission method provided by the present disclosure can be applied in the system architecture shown in FIG. 1, for example, can be applied in a first node (such as a terminal).

[0036] As shown in FIG. 2, the data transmission method provided by the present disclosure can include S201-S203.

[0037] S201, the first node acquires a first pilot sequence.

[0038] The pilot sequence is usually used for channel estimation, synchronization and frequency offset correction.

[0039] In some embodiments, acquiring the first pilot sequence includes that the first node selects the first pilot sequence from a pilot sequence set. The pilot sequence set includes pilot sequences that are mutually orthogonal and / or have mutual correlation.

[0040] In some embodiments, the pilot sequence set is commonly known by the transceiving two ends (the first node and the second node).

[0041] In some embodiments, selecting the first pilot sequence from the pilot sequence set includes at least one of the following manners: selecting the first pilot sequence from the pilot sequence set according to signaling; randomly selecting the first pilot sequence from the pilot sequence set; selecting the first pilot sequence from the pilot sequence set according to pre-setting.

[0042] In some embodiments, the first node can determine the pilot sequence set according to signaling, and / or the first node can determine the pilot sequence set according to pre-setting.

[0043] It should be noted that in an actual communication system, the pilot sequence processing is used not only for channel estimation, but also for functions such as sampling frequency offset (SFO) estimation, timing offset (TO) estimation, and collision probability reduction. Therefore, in some embodiments, the pilot sequences in the pilot sequence set satisfy at least one of the following: the autocorrelation of each pilot sequence is normalized to 1; each pilot sequence is mutually orthogonal; the mutual correlation between each pilot sequence is the same; and the number of non-zero elements in each pilot sequence is the same.

[0044] S202, the first node generates a first data symbol.

[0045] The first data symbol is obtained by encoding and modulating the first data to be transmitted using a spreading sequence.

[0046] In some embodiments, the first data is data to be transmitted, and can include at least one of the following: service data, node identification, first pilot sequence information, and spreading sequence information.

[0047] In some embodiments, the encoding includes at least one of the following: channel coding; waveform coding; and spreading code coding (i.e., encoding using a spreading sequence).

[0048] The channel coding mentioned here can be convolutional codes, polar codes, low-density parity check codes (LDPC), Turbo codes, etc.

[0049] The waveform encoding mentioned here can be Manchester encoding, FM0 encoding, Miller encoding, etc.

[0050] In some embodiments, the modulation process described above includes at least one of the following: OOK, binary phase shift keying (BPSK).

[0051] In some embodiments, during the process of the first node performing extended code encoding using an extended sequence, the first node may obtain the extended sequence based on at least one of the following methods: selecting an extended sequence from a set of extended sequences according to signaling; randomly selecting an extended sequence from a set of extended sequences; or selecting an extended sequence from a set of extended sequences according to a preset setting.

[0052] In some embodiments, the extended sequence set is known to both the sending and receiving ends (the first node and the second node).

[0053] In some embodiments, the extended sequence set can be an orthogonal extended sequence set, such as the Walsh sequence, the Hadamard sequence, etc. It can also be a non-orthogonal extended sequence set, such as the Barker sequence, etc.

[0054] In some embodiments, the first node may determine the extended sequence set based on signaling, and / or the first node may determine the extended sequence set based on a preset setting.

[0055] S203, The first node sends the first symbol sequence.

[0056] The first symbol sequence consists of the first pilot sequence and the first data symbol.

[0057] After acquiring the first pilot sequence and the first data symbol, the first node can map the first pilot sequence and the first data symbol together onto the transmission resource and then send them to the second node.

[0058] Figure 3 is a schematic flowchart of another data transmission method provided by an embodiment of this disclosure. Exemplarily, the data transmission method provided by this disclosure can be applied to the system architecture shown in Figure 1, and can be applied to a second node (such as a base station).

[0059] As shown in Figure 3, the data transmission method provided in this disclosure may include S301-S303.

[0060] S301, the second node receives a second symbol sequence.

[0061] The second symbol sequence is composed of a second pilot sequence and a second data symbol, and the second symbol sequence includes at least one first symbol sequence.

[0062] It should be understood that in the scheduling-free transmission process, the second node can receive a plurality of first symbol sequences sent by the first nodes at the same time, and the received data is the second symbol sequence for the second node, which can also be referred to as a signal mixed by multiple first nodes. The second node can process the second symbol sequence to complete the processes of active first node detection, data separation and demodulation, that is, perform S302-S303 described below.

[0063] S302, the second node pre-processes the second data symbol based on a channel estimation result to obtain a third data symbol.

[0064] The channel estimation result is obtained based on channel estimation of the second pilot sequence and the pilot sequence set.

[0065] It should be understood that the second node detects the received pilot symbol using the pilot sequence set, identifies the pilot sequence sent by the first node, and performs channel estimation to obtain the channel estimation result. Then, the second node can restore the orthogonality or cross-correlation of the spreading sequence in the second data symbol after pre-processing the second data symbol based on the channel estimation result, which can facilitate the subsequent analysis process of the second node, thereby ensuring the performance of multiple access.

[0066] S303, the second node analyzes and processes the third data symbol to obtain first data of at least one first node.

[0067] In some embodiments, the analysis and processing includes at least one of the following: detection and separation of the third data symbol based on the spreading sequence set; channel estimation; channel equalization; demodulation; decoding.

[0068] The above-mentioned detection refers to that the second node detects the pre-processed third data symbol using the spreading sequence set, identifies the spreading sequence selected by the first node when transmitting the first data, completes the detection process, and obtains the first data symbol sent by the first node.

[0069] The above-mentioned channel estimation and channel equalization refer to that the second node performs secondary channel estimation on the data symbol of the first node based on the constellation characteristics of the modulation mode, and uses the channel estimation result to perform channel equalization to obtain the processed data symbol.

[0070] The above demodulation and decoding refer to that the second node demodulates and decodes the first data symbol of the first node, and can determine whether the decoding is correct according to a cyclical redundancy check (CRC) result. Since it is a contention-free scheduling transmission, the identity of the first node can be carried in the data part of the first data symbol, and the second node can obtain the identity information of the first node and the data transmitted by the first node after correctly decoding the data. In addition, the data part can also carry pilot sequence information, spreading sequence information and the like.

[0071] In some embodiments, the data transmission method provided by the embodiments of the present disclosure further includes the following S304A-S306A.

[0072] S304A, processing the first data of the at least one first node to obtain the first data symbol of the at least one first node.

[0073] S305A, eliminating the first data symbol of the at least one first node from the third data symbol.

[0074] S306A, performing parsing processing on the third data symbol after elimination to obtain the first data of other first nodes.

[0075] In some embodiments, the data transmission method provided by the embodiments of the present disclosure further includes the following S304B-S306B.

[0076] S304B, processing the first data of the at least one first node to obtain at least one first symbol sequence of the at least one first node.

[0077] S305B, eliminating the at least one first symbol sequence of the at least one first node from the second symbol sequence.

[0078] S306B, performing preprocessing and parsing processing on the second symbol sequence after elimination to obtain the first data of other first nodes.

[0079] It should be understood that for the data decoded correctly, the second node can generate the first data symbol sent by the first node after re-encoding, modulating, spreading code encoding, waveform modulation, etc. of the data output by decoding, and generate the pilot symbol sent by the first node according to the pilot information, and the pilot symbol and the first data symbol together constitute the first symbol sequence sent by the first node. In the spreading code encoding process, the second node determines the spreading sequence of the first node for encoding according to the spreading sequence information. Then, the second node reconstructs the received data symbol using the secondary channel estimation result, and then eliminates the reconstructed data symbol from the third data symbol to realize interference cancellation. Then the second node can identify and detect the first data transmitted by other first nodes from the third data symbol after cancellation (i.e., perform S306A). The second node can also use the first symbol sequence reconstructed by all decoded correctly nodes for least square (LS) channel estimation to obtain updated channel estimation results, and reconstruct the received symbol sequence for interference cancellation based on the updated channel estimation results. Then the second node can identify and detect the first data transmitted by other first nodes from the second symbol sequence after cancellation (i.e., perform S306B).

[0080] It should be understood that the above S304A-S306A or S304B-S306B can be repeatedly performed until no new active first node can be identified, or until a specified number of iterations is reached.

[0081] The data transmission method provided by the embodiments of the present disclosure will be described in detail below in combination with some embodiments and formulas.

[0082] In the grant-free transmission, the second node allows multiple first nodes to perform data transmission in the same time-frequency resource, that is, the superimposed data symbol of multiple first nodes received by the second node can be represented as:

[0083] wherein x u represents the data symbol sent by the first node u. y d represents the superimposed data symbol of U first nodes received by the second node, h u represents the channel experienced by the first node u, n d represents additive white Gaussian noise (AWGN).

[0084] In an implementation manner, when the first node modulates the data symbol to be sent to the carrier signal with BPSK waveform for transmission, the superimposed data symbol of multiple first nodes received by the second node can be further represented as

[0085] wherein c urepresents the spreading sequence selected by the first node u, i.e., the spreading sequence selected by the first node u from the spreading sequence set C according to a pre-set manner, or a spreading sequence selected by the first node u according to signaling configuration or randomly. u represents the data symbol after encoding and modulation of the first node u.

[0086] Exemplarily, the spreading sequence set C can be an orthogonal spreading sequence set, such as a Walsh sequence, a Hadamard sequence, etc., and satisfies: for any two different spreading sequences c i and c j in the set C, there is

[0087] For another example, the spreading sequence set C can also be a non-orthogonal spreading sequence set, such as a Barker sequence, etc., and satisfies: for any two different spreading sequences c i and c j in the set C, there is i.e., the spreading sequences in the set have a higher autocorrelation peak and a lower cross-correlation peak.

[0088] Since the first node modulates the data symbol to be transmitted to the carrier signal in the BPSK waveform for transmission, the second received multi-first node mixed data symbol can effectively preserve the properties of the spreading sequence set, and thus the second node can use it for detection and recovery. In order to simplify the analysis, taking the example of 2 first nodes transmitting data at the same time with non-collision spreading sequences, the first node 1 and the first node 2 select different spreading sequences c1 and c2, then the above formula (2) can be written as y d = h1c1s1 + h2c2s2 + n d formula (3)

[0089] In the scheduling-free transmission, since the second node does not know which first nodes are currently accessed and transmit data, the second node can perform active first node detection through the spreading sequence, and then perform channel equalization and subsequent data separation and demodulation. The second node can use the spreading sequence set C to perform active first node detection on the received multi-first node mixed data symbol y d . Then the estimated value of the data symbol can be represented as

[0090] In the embodiment of the present disclosure, taking the decorrelation algorithm as an example, if the decorrelation algorithm is used, then there is Other receiving algorithms can also be used, such as minimum mean squared error (MMSE) equalization, maximum likelihood (ML) algorithm, zero force (ZF) algorithm, etc. Then the second node will perform equalization demodulation decoding to complete detection of multiple first nodes.

[0091] However, when the first node modulates the data symbol to be sent to the carrier signal in the OOK waveform for transmission, the data symbol superimposed by multiple first nodes received by the second node is represented as

[0092] where s u is the data symbol after BPSK modulation. It can be seen that due to the OOK waveform, the originally orthogonal spreading codes in each first node are no longer orthogonal, resulting in difficulty in demodulation and recovery of data at the receiving end. Taking the example of 2 first nodes transmitting data simultaneously in non-collision spreading sequences. The first node 1 and the first node 2 select different spreading sequences c1 and c2, then the foregoing formula (2) can be written as

[0093] Further, the estimated symbol of the data symbol obtained by the second node can be represented as

[0094] and

[0095] It can be seen that due to the OOK waveform, the originally orthogonal spreading sequences in each first node are no longer orthogonal, and the second node introduces interference terms of data symbols of other first nodes into the data symbol estimation of each first node, which are and Therefore, compared with the estimated symbol under the BPSK waveform, the estimated symbol at this time has a lower signal-to-interference-and-noise ratio, further reducing the performance of subsequent equalization demodulation and decoding, and ultimately causing deterioration of the performance of multiple access.

[0096] To solve the above problems, the present disclosure proposes a data transmission method combined with a pilot sequence. Under this method, the base station can use the characteristics of the pilot sequence to perform channel estimation, and based on the channel estimation result, pre-process the superimposed data symbol to restore the orthogonality (or, cross-correlation) of the spreading sequence in the data symbol, thereby ensuring the performance of multiple access based on the OOK waveform.

[0097] Similarly, since multiple first nodes are allowed to transmit data in the same time-frequency resource, the pilot sequence superimposed by multiple first nodes received by the second node can be represented as

[0098] wherein, p u represents the pilot sequence transmitted by the first node u, i.e. the spreading sequence determined by the first node u from the pilot sequence set P according to a pre-set manner or configured by signaling or randomly selected. y p represents the pilot sequence received by the second node superimposed by U first nodes, n p represents the additive white Gaussian noise (AWGN).

[0099] Further, the second node performs channel estimation based on the pilot sequence. Assuming that the second node obtains ideal channel estimation results of each first node based on the pilot sequence, the received data y d The process of pre-processing so that the received spreading sequence of each first node becomes orthogonal is as follows:

[0100] Still taking the example of 2 first nodes transmitting data simultaneously with non-collision spreading sequences, the first node 1 and the first node 2 select different spreading sequences c1 and c2, the second node obtains the data symbol estimation based on the pre-processed received data y d The estimation symbol of the data symbol obtained by the second node can be expressed as

[0101] and

[0102] It can be seen that the signal-to-interference-and-noise ratio of the current estimation symbol is improved, which can improve the performance of subsequent equalization demodulation and decoding, thereby improving the performance of multiple access under the OOK waveform.

[0103] In some embodiments, the data transmission method proposed by the present disclosure is described taking two first nodes as an example. It should be understood that the present disclosure does not limit the number of first nodes simultaneously transmitting data, nor the number of colliding pilots on the same time-frequency resource. For example, K (K is greater than or equal to 2) first nodes simultaneously transmit data on the same time-frequency resource, wherein the pilots of at least 2 first nodes collide, and the pilots of the remaining first nodes do not collide. For another example, the pilots of the first node 1 and the first node 2 collide, and the pilots of the first node 3 to the first node K do not collide. For another example, the pilots of the first node 1 and the first node 2 collide, and the pilots of the first node 3 and the first node 4 collide, and the pilots of the first node 5 to the first node K do not collide. For another example, the pilots of the first node 1, the first node 2 and the first node 3 collide, and the pilots of the first node 4 to the first node K do not collide.

[0104] Embodiment one

[0105] In the embodiment, the pilot sequence set has the following characteristics: the autocorrelation of each pilot sequence is normalized to 1; and the pilot sequences are mutually orthogonal. That is, for the pilot sequence set P = [p1, p2, …, p|P|] known to both the transceiver, there is |P| ] t and for any 1≤i, j≤|P| and i≠j, there is |p i | 2 = 1, where |P| represents the size of the pilot sequence set P; [·] t represents sequence transposition.

[0106] Exemplarily, taking the pilot sequence length as 3, the pilot sequence set in the embodiment can be or or or The embodiment of the present disclosure does not make a limitation in this regard.

[0107] Exemplarily, taking the pilot sequence length as 4, the pilot sequence set in the embodiment can be or or or The embodiment of the present disclosure does not make a limitation in this regard.

[0108] Exemplarily, taking the pilot sequence length as 5, the pilot sequence set in the embodiment can be or or or or or or The embodiment of the present disclosure does not make a limitation in this regard.

[0109] Exemplarily, taking the pilot sequence length as 6, the pilot sequence set in the embodiment can be

[0110] or

[0111] or

[0112] or

[0113] or

[0114] or

[0115] Also, the first node can be configured to select a pilot sequence from the set of pilot sequences according to a pre-set manner or randomly.

[0116] The present disclosure is not limited in this regard.

[0117] In the present embodiment, the first node selects a pilot sequence from the set of pilot sequences according to signaling configuration or according to a pre-set manner or randomly, and transmits the pilot sequence together with the data symbol to be transmitted.

[0118] When the first node has service data to be transmitted, the first node performs channel coding, waveform coding, modulation, spreading code coding and the like on the service data to form a data symbol to be transmitted. Then the first node maps the pilot sequence and the data symbol to be transmitted onto a transmission resource for transmission.

[0119] In the present embodiment, the second node receives the superimposed symbol sequence of multiple first nodes, which includes pilot symbols and data symbols. Further, the second node performs channel estimation based on the pilot symbols.

[0120] In one example, the first node 1 and the first node 2 do not collide in pilot. Then the superimposed pilot symbols of multiple first nodes received by the second node can be represented as y p = h1p1+ h2p2+ n p

[0121] Then, the channel estimation of the second node based on the pilot symbols is

[0122] By setting a suitable threshold value, the effective channel estimation can be obtained as and Thus, the pre-processing of the aforementioned formula (8) under the actual channel estimation is

[0123] wherein, Further, the second node obtains the estimated symbol of the data symbol based on the pre-processed received data y d The process of obtaining the estimated symbol of the data symbol is as described above and will not be described again here.

[0124] In another example, the first node 1 and the first node 2 collide in pilot. Then the superimposed pilot symbols of multiple first nodes received by the second node can be represented as y p = h1p1+ h2p1+ n p

[0125] Then, the channel estimation of the second node based on the pilot symbols is

[0126] By setting a suitable threshold value, the effective and channel estimation can be obtained as Therefore, the preprocessing of the aforementioned formula (8) under this actual channel estimation is:

[0127] in, Furthermore, the second node, based on the preprocessed received data y d The process of estimating the symbol of the obtained data symbol is as described above and will not be repeated here.

[0128] Example 2

[0129] The pilot sequence set in the aforementioned embodiment 1 has the following characteristics: the autocorrelation of each pilot sequence is normalized to 1; and each pilot sequence is orthogonal to the others.

[0130] In this embodiment, the pilot sequence set has the following characteristics: the autocorrelation of each pilot sequence is normalized to 1; and the cross-correlation among the pilot sequences is the same. That is, for a set of pilot sequences P = [p1, p2, ..., p...] that is known to both the transmitting and receiving ends... |P| ] t And for any 1≤i,j≤|P| and i≠j, we have |p i | 2 =1, Where |P| represents the size of the pilot sequence set P; [·] t Indicates sequence transpose; 0 <a<1。

[0131] For example, taking a pilot sequence length of 3 as an example, the pilot sequence set in this embodiment can be: at this time It can also be at this time It can also be at this time This disclosure does not limit the scope of the embodiments.

[0132] For example, taking a pilot sequence length of 4 as an example, the pilot sequence set in this embodiment can be: at this time It can also be at this time It can also be at this time This disclosure does not limit the scope of the embodiments.

[0133] For example, taking a pilot sequence length of 5 as an example, the pilot sequence set in this embodiment can be:

[0134] At this time, a = 3 / 4;

[0135] It can also be At this time, a = 2 / 3;

[0136] Also, a = 2 / 3. At this time

[0137] Also, a = 2 / 3. At this time a = 3 / 4.

[0138] Also, a = 2 / 3. At this time a = 2 / 3.

[0139] Also, a = 2 / 3. At this time

[0140] Also, a = 2 / 3. At this time The embodiment of the present disclosure is not limited in this regard.

[0141] Exemplarily, taking the pilot sequence length of 6 as an example, the pilot sequence set in the embodiment can be At this time a = 4 / 5.

[0142] Also, a = 2 / 3. At this time a = 3 / 4.

[0143] Also, a = 2 / 3. At this time

[0144] Also, a = 2 / 3. At this time a = 2 / 3.

[0145] Also, a = 2 / 3. At this time a = 1 / 3.

[0146] Also, a = 2 / 3. At this time a = 1 / 2. The embodiment of the present disclosure is not limited in this regard.

[0147] In the embodiment, the second node receives a symbol sequence superimposed by multiple first nodes, and the symbol sequence includes pilot symbols and data symbols. Further, the second node performs channel estimation based on the pilot symbols. The channel estimation based on the pilot symbols in the embodiment is a sum estimation of effective channels, specifically:

[0148] Wherein, the channel estimation in the set M Satisfies | M | represents the size of the set M, and b is a threshold for judging whether it is an effective channel estimation.

[0149] In one example, the first node 1 and the first node 2 do not have pilot collision. Then, the pilot symbols superimposed by multiple first nodes received by the second node can be represented as y p = h1p1 + h2p2 + np

[0150] Then, the channel estimate of the second node based on the pilot symbols is

[0151] By setting a proper threshold b, the effective channel estimate set can be obtained and and |M| = 2. Further, the effective channel and estimate are

[0152] Thus, the pre-processing of the aforementioned formula (8) under this actual channel estimate is

[0153] where, Further, the second node obtains the estimated symbol of the data symbol based on the pre-processed received data y d The process of obtaining the estimated symbol of the data symbol from the pre-processed received data y

[0154] In yet another example, the first node 1 and the first node 2 have pilot collision. Then, the pilot symbol received by the second node superimposed by multiple first nodes can be represented as y p = h1p1+ h2p1+ n p

[0155] Then, the channel estimate of the second node based on the pilot symbols is

[0156] By setting a proper threshold b, the effective channel estimate set can be obtained and and |M| = 1. Further, the effective channel and estimate are

[0157] Thus, the pre-processing of the aforementioned formula (8) under this actual channel estimate is

[0158] where, Further, the second node obtains the estimated symbol of the data symbol based on the pre-processed received data y d The process of obtaining the estimated symbol of the data symbol from the pre-processed received data y

[0159] Embodiment Three

[0160] The difference between this embodiment and the aforementioned embodiments is that the pilot sequence set has different characteristics.

[0161] In the embodiment, the pilot sequence set has the following characteristics: the number of non-zero elements of each pilot sequence is the same. That is, for the pilot sequence set P = [p1, p2, …, pi, …, p|P|] known to both the transceiver, there is |p1|0= |p2|0= … = |pi|0= … = |p|P||0, where |P| represents the size of the pilot sequence set P, |·|0 represents the L0 norm, i.e., the number of non-zero elements in the sequence, and l is an integer. |P| ] t And for any 1≤i, j≤|P| and i≠j, there is |p i |0= |p j |0= l, where |P| represents the size of the pilot sequence set P, |·|0 represents the L0 norm, i.e., the number of non-zero elements in the sequence, and l is an integer.

[0162] For example, taking a pilot sequence length of 3 as an example, the pilot sequence set in the embodiment can be In this case, l = 1; or In this case, l = 2. The embodiment of the present disclosure does not limit this.

[0163] For example, taking a pilot sequence length of 4 as an example, the pilot sequence set in the embodiment can be In this case, l = 3;

[0164] Or In this case, l = 2;

[0165] Or In this case, l = 1. The embodiment of the present disclosure does not limit this.

[0166] For example, taking a pilot sequence length of 5 as an example, the pilot sequence set in the embodiment can be In this case, l = 1;

[0167] Or In this case, l = 2;

[0168] Or In this case, l = 3;

[0169] Or In this case, l = 4. The embodiment of the present disclosure does not limit this.

[0170] For example, taking a pilot sequence length of 5 as an example, the pilot sequence set in the embodiment can be In this case, l = 1;

[0171] Or In this case, l = 2;

[0172] Or In this case, l = 3;

[0173] Or In this case, l = 4;

[0174] Also, for At this time, l = 5. The embodiments of the present disclosure do not limit this.

[0175] In the present embodiment, the second node receives a plurality of first node superimposed symbol sequences, and the symbol sequences include pilot symbols and data symbols. Further, the second node performs channel estimation based on the pilot symbols. Wherein, the channel estimation based on the pilot symbols in the present embodiment is the sum estimation of effective channels, specifically:

[0176] Wherein, L represents the length of the pilot sequence, and l represents the number of non-zero elements in the pilot sequence. The i-th element of the received pilot symbol y p .

[0177] In one example, the length of each pilot sequence in the pilot sequence set P is L, and the number of non-zero elements in each pilot sequence is l. The first node 1 and the first node 2 do not collide with the pilot. Then, the plurality of first node superimposed pilot symbols received by the second node can be represented as y p = h1p1+ h2p2+ n p

[0178] Then, the element-by-element addition sum of the received pilot symbol sequence is

[0179] Therefore, the sum channel estimation of the received pilot symbol determined by the second node is

[0180] Therefore, the preprocessing of the aforementioned formula (8) under the actual channel estimation is

[0181] Wherein, Further, the second node obtains the estimated symbol of the data symbol based on the preprocessed received data y d The process of obtaining the estimated symbol of the data symbol is as described above, which will not be repeated here.

[0182] In another example, the first node 1 and the first node 2 collide with the pilot. Then, the plurality of first node superimposed pilot symbols received by the second node can be represented as y p = h1p1+ h2p1+ n p

[0183] Then, the element-by-element addition sum of the received pilot symbol sequence is

[0184] Therefore, the sum channel estimation determined by the second node based on the received pilot symbol is

[0185] Thus, the pre-processing of the aforementioned formula (8) under the actual channel estimation is

[0186] wherein, Further, the second node obtains the estimation of the data symbol based on the pre-processed received data y d The process of obtaining the estimation of the data symbol from the obtained data symbol is as previously described, and thus will not be described again here.

[0187] The embodiments of the present disclosure provide a data transmission method. The first node transmits a pilot sequence and a symbol sequence jointly, so that the second node can perform channel estimation based on the pilot symbol, pre-process the received data symbol based on the channel estimation result, ensure the orthogonality or cross-correlation of the spreading sequence in the received data symbol, and thus enable the second node to correctly separate and parse the data transmitted by each first node from the received symbol sequence, thereby improving the performance of code division multiple access.

[0188] It can be understood that, in order to implement the above functions, the communication device comprises hardware structures and / or software modules corresponding to each function. Those skilled in the art should easily realize that, in combination with the algorithm steps of each example described in the embodiments of the present disclosure, the present disclosure can be implemented in the form of hardware or a combination of hardware and computer software. Whether a certain function is implemented in hardware or computer software driven hardware depends on the specific application and design constraints of the technical solution. Professional technicians can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of the present disclosure.

[0189] The embodiments of the present disclosure can divide the functional modules of the communication device according to the method embodiments described above. For example, each functional module can be divided according to each function, or two or more functions can be integrated into one functional module. The integrated module can be implemented in the form of hardware or software. It should be noted that the division of modules in the embodiments of the present disclosure is illustrative, and is only a logical functional division. Actual implementation can have another division manner. The following will be described taking the example of dividing each functional module according to each function.

[0190] FIG. 4 is a structural schematic diagram of a communication device provided by an embodiment of the present disclosure, which can execute the data transmission method provided by the method embodiments described above. As shown in FIG. 4, the communication device comprises an acquisition module 401, a generation module 402 and a transmission module 403.

[0191] The acquisition module 401 is configured to acquire a first pilot sequence.

[0192] The generating module 402 is configured to generate a first data symbol, wherein the first data symbol is obtained by encoding and modulating first data to be transmitted by using an extension sequence.

[0193] The sending module 403 is configured to send the first symbol sequence, wherein the first symbol sequence is composed of the first pilot sequence and the first data symbol.

[0194] In some embodiments, the acquiring module 401 is configured to select the first pilot sequence from a pilot sequence set, wherein the pilot sequence set comprises pilot sequences that are orthogonal to each other and / or have mutual correlation.

[0195] In some embodiments, the selection of the first pilot sequence from the pilot sequence set comprises at least one of the following: selecting the first pilot sequence from the pilot sequence set according to signaling; randomly selecting the first pilot sequence from the pilot sequence set; and selecting the first pilot sequence from the pilot sequence set according to pre-setting.

[0196] In some embodiments, the pilot sequences in the pilot sequence set satisfy at least one of the following: the autocorrelation of each pilot sequence is normalized to 1; the pilot sequences are orthogonal to each other; the mutual correlation between the pilot sequences is the same; and the number of non-zero elements in each pilot sequence is the same.

[0197] In some embodiments, the communication apparatus further comprises a determining module 404. The determining module 404 is configured to determine the pilot sequence set according to signaling and / or pre-setting.

[0198] In some embodiments, the encoding comprises at least one of the following: channel coding; waveform coding; and spreading code coding.

[0199] In some embodiments, the acquiring module 401 is further configured to acquire the extension sequence based on at least one of the following: selecting the extension sequence from an extension sequence set according to signaling; randomly selecting the extension sequence from the extension sequence set; and selecting the extension sequence from the extension sequence set according to pre-setting.

[0200] In some embodiments, the determining module 404 is further configured to determine the extension sequence set according to signaling and / or pre-setting.

[0201] In some embodiments, the first data comprises at least one of the following: service data; a node identifier; first pilot sequence information; and extension sequence information.

[0202] FIG. 5 is a structural schematic diagram of another communication apparatus provided by an embodiment of the present disclosure, which can perform the data transmission method provided by the method embodiments. As shown in FIG. 5, the communication apparatus comprises a receiving module 501 and a processing module 502.

[0203] The receiving module 501 is configured to receive a second symbol sequence, the second symbol sequence being composed of a second pilot sequence and second data symbols; the second symbol sequence including at least one first symbol sequence.

[0204] The processing module 502 is configured to pre-process the second data symbols based on a channel estimation result to obtain third data symbols; the channel estimation result being obtained based on channel estimation of the second pilot sequence and the pilot sequence set.

[0205] The processing module 502 is further configured to perform parsing processing on the third data symbols to obtain the first data of the at least one first node.

[0206] In some embodiments, the processing module 502 is configured to subtract the channel estimation result from the second data symbols to obtain the third data symbols.

[0207] In some embodiments, the parsing processing includes at least one of the following: detection and separation of the third data symbols based on the spreading sequence set; channel estimation; channel equalization; demodulation; decoding.

[0208] In some embodiments, the processing module 502 is further configured to process the first data of the at least one first node to obtain first data symbols of the at least one first node; eliminate the first data symbols of the at least one first node from the third data symbols; and perform parsing processing on the third data symbols after elimination to obtain the first data of other first nodes.

[0209] In some embodiments, the processing module 502 is further configured to process the first data of the at least one first node to obtain at least one first symbol sequence; eliminate the at least one first symbol sequence from the second symbol sequence; and perform pre-processing and parsing processing on the second symbol sequence after elimination to obtain the first data of other first nodes.

[0210] In some embodiments, the first data includes at least one of the following: service data; node identifier; first pilot sequence information; spreading sequence information.

[0211] In the case of implementing the functions of the above integrated modules in the form of hardware, the embodiments of the present disclosure provide another structure of the communication apparatus involved in the above embodiments. As shown in FIG. 6, the communication apparatus 60 includes a memory 601, a processor 602, a communication interface 603, and a bus 604.

[0212] The memory 601 can be a read-only memory (ROM) or other type of static storage device that can store static information and instructions, can be a random access memory (RAM) or other type of dynamic storage device that can store dynamic information and instructions, can be an electrically erasable programmable read-only memory (EEPROM), a magnetic disk storage medium, or other magnetic storage device, or any other medium capable of carrying or storing desired program code in the form of instructions or data structures and that can be accessed by a computer, but is not limited thereto.

[0213] The processor 602 can be a logical block, a module and a circuit that implement or execute various exemplary methods described in combination with the embodiments of the present disclosure. The processor 602 can be a central processing unit, a general-purpose processor, a digital signal processor, an application-specific integrated circuit, a field programmable gate array or other programmable logic device, a transistor logic device, a hardware component or any combination thereof. The processor 602 can also implement or execute various exemplary logical blocks, modules and circuits described in combination with the embodiments of the present disclosure. The processor 602 can also be a combination of computing functions, such as a combination of one or more microprocessors, a combination of a digital signal processor (DSP) and a microprocessor, and the like.

[0214] The communication interface 603 is configured to connect with other devices through a communication network. The communication network can be an Ethernet, a wireless access network, a wireless local area network (WLAN), and the like.

[0215] In some implementations, the memory 601 can exist independently of the processor 602, and the memory 601 can be connected with the processor 602 through the bus 604, for storing instructions or program codes. When the processor 602 invokes and executes the instructions or program codes stored in the memory 601, the methods provided by the embodiments of the present disclosure can be implemented.

[0216] In some implementations, the memory 601 can also be integrated with the processor 602.

[0217] Bus 604, which can be an extended industry standard architecture (EISA) bus, a peripheral component interconnect (PCI) bus, or another type of bus, connects the various components in the computing device. The bus 604 can be split into buses, for example, an address bus, a data bus, a control bus, etc. For simplicity, the bus 604 is shown in Figure 6 as a single bus, but it is understood that the bus 604 can include multiple buses.

[0218] In some embodiments, the memory 601 stores executable instructions which, when executed by the processor 602, cause the communication device to perform the method of any of the above embodiments.

[0219] Some embodiments of the present disclosure provide a computer-readable storage medium (for example, a non-transitory computer-readable storage medium) having stored computer program instructions, which, when executed on a computer, cause the computer to perform the method of any of the above embodiments.

[0220] By way of example, the above computer-readable storage medium can include, but is not limited to, magnetic storage devices (for example, hard disks, floppy disks, or magnetic tapes), optical disks (for example, compact disks (CDs), digital versatile disks (DVDs), etc.), smart cards, and flash memory devices (for example, Erasable Programmable Read-Only Memory (EPROM), card, stick, or key drive, etc.). The various computer-readable storage media described in the present disclosure can represent one or more devices and / or other machine-readable storage media for storing information. The term "machine-readable storage medium" can include, but is not limited to, wireless channels and various other media capable of storing, containing, and / or carrying instructions and / or data.

[0221] The embodiments of the present disclosure provide a computer program product containing instructions, which, when executed on a computer, cause the computer to perform the method of any of the above embodiments.

[0222] The above description is merely a specific implementation of the present disclosure, but the protection scope of the present disclosure is not limited thereto. Any change or replacement within the technical scope disclosed in the present disclosure should be covered within the protection scope of the present disclosure. Therefore, the protection scope of the present disclosure should be subject to the protection scope of the claims.

Claims

1. A data transmission method applied to a first node, wherein, The method comprises: acquiring a first pilot sequence; generating a first data symbol, wherein the first data symbol is obtained by encoding and modulating first data to be transmitted using an extension sequence; transmitting a first symbol sequence, wherein the first symbol sequence is composed of the first pilot sequence and the first data symbol.

2. The method of claim 1, wherein, The acquiring of the first pilot sequence comprises: selecting the first pilot sequence from a pilot sequence set; wherein the pilot sequence set comprises pilot sequences that are mutually orthogonal and / or have mutual correlation.

3. The method of claim 2, wherein, The selecting of the first pilot sequence from the pilot sequence set comprises at least one of the following: selecting the first pilot sequence from the pilot sequence set according to signaling; randomly selecting the first pilot sequence from the pilot sequence set; or selecting the first pilot sequence from the pilot sequence set according to pre-setting.

4. The method of claim 2, wherein, The pilot sequences in the pilot sequence set satisfy at least one of the following: the autocorrelation of each pilot sequence is normalized to 1; each pilot sequence is mutually orthogonal; the mutual correlation between each pilot sequence is the same; or the number of non-zero elements in each pilot sequence is the same.

5. The method according to claim 2, further comprising: determining the pilot sequence set according to signaling; and / or determining the pilot sequence set according to pre-setting. The encoding process comprises at least one of the following:

6. The method of claim 1, wherein, channel coding; waveform coding; or spreading code coding.

7. The method according to claim 1, further comprising: acquiring the extension sequence based on at least one of the following: selecting the extension sequence from an extension sequence set according to signaling; randomly selecting the extension sequence from an extension sequence set; or selecting the extension sequence from an extension sequence set according to pre-setting.

8. The method according to claim 7, further comprising: determining the extension sequence set according to signaling; and / or determining the extension sequence set according to pre-setting. The first data comprises at least one of the following: service data; 9. The method of claim 1, wherein, node identifier; first pilot sequence information; extension sequence information. The method comprises: receiving a second symbol sequence, wherein the second symbol sequence is composed of a second pilot sequence and a second data symbol, and the second symbol sequence comprises at least one first symbol sequence; 10. A data transmission method applied to a second node, wherein, preprocessing the second data symbol based on a channel estimation result to obtain a third data symbol, wherein the channel estimation result is obtained based on channel estimation of the second pilot sequence and a pilot sequence set; parsing the third data symbol to obtain first data of at least one first node. The preprocessing of the second data symbol based on the channel estimation result to obtain the third data symbol comprises: subtracting the channel estimation result from the second data symbol to obtain the third data symbol.

11. The method of claim 10, wherein, The parsing process comprises at least one of the following: detecting and separating the third data symbol based on an extension sequence set; 12. The method of claim 10, wherein, channel estimation; channel equalization; demodulation; or decoding.

13. The method according to claim 10, further comprising: ​ ​ processing the first data of the at least one first node to obtain first data symbols of the at least one first node; eliminating the first data symbols of the at least one first node from the third data symbols; performing parsing processing on the third data symbols after elimination to obtain first data of other first nodes.

14. The method of claim 10, further comprising: processing the first data of the at least one first node to obtain at least one first symbol sequence; eliminating the at least one first symbol sequence from the second symbol sequence; performing preprocessing and parsing processing on the second symbol sequence after elimination to obtain first data of other first nodes.

15. The method of claim 10, wherein, The first data comprises at least one of: service data; node identifier; first pilot sequence information; spreading sequence information.

16. A communications device comprising: a processor and a memory for storing instructions executable by the processor; wherein the processor is configured to execute the instructions to cause the communication device to perform the data transmission method according to any one of claims 1-15.

17. A computer readable storage medium, wherein, The computer readable storage medium has stored thereon computer instructions which, when executed on a communication device, cause the communication device to perform the data transmission method according to any one of claims 1-15.

18. A computer program product, wherein, The computer program product contains computer instructions which, when executed on a computer, cause the computer to perform the data transmission method according to any one of claims 1-15.

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