A cellular Internet of Things relay NOMA transmission method and system

Abstract

The present invention discloses a cellular Internet of Things relay NOMA transmission method and system. In the present invention, an Internet of Things signal end uses a first radio frequency NOMA signal sent by a signal sending end to load its own Internet of Things information and generate a first reflected signal. The first reflected signal is received by the signal sending end and the signal relay end respectively. The signal relay end obtains information required by an edge user end according to the first reflected signal and the first radio frequency NOMA signal, encodes and generates a second radio frequency NOMA signal for transmission. The edge user receives the second radio frequency NOMA signal to obtain information required by itself. The Internet of Things signal end uses the second radio frequency NOMA signal to load its own Internet of Things information and generate a second reflected signal. The second reflected signal and the second radio frequency NOMA signal are received by the signal sending end. During the entire signal transmission process, the edge user and the Internet of Things signal end share spectrum, and the signal relay end and the reflected signal are used to expand the signal coverage while reducing energy consumption.

Description

Technical Field

[0001] The present invention relates to a cellular Internet of Things relay NOMA transmission method and system, belonging to the technical field of mobile communications. Background Art

[0002] Currently, cellular IoT users already coexist with a large number of IoT sensors. Cellular IoT users and IoT sensors mainly access the network through traditional orthogonal multiple access. Although the two can share spectrum resources, they actually have a symbiotic relationship. Due to the introduction of a large number of IoT sensors, the signals of cellular users will be greatly interfered with. Therefore, the current premise of IoT sensors and cellular users sharing spectrum resources is to damage the performance of cellular users. In order to solve the above problems, non-orthogonal multiple access technology is introduced. By adopting non-orthogonal multiplexing of power domain resources, multiple users can share other physical layer resources at the same time, effectively improving the system spectrum efficiency and node connection density, but it will result in a small signal range coverage and excessive node power consumption. Summary of the invention

[0003] The purpose of the present invention is to overcome the shortcomings of the prior art and provide a cellular Internet of Things relay NOMA transmission method and system, which improves the spectrum efficiency of cellular users and Internet of Things sensors, expands the signal coverage range, and solves the current problem of low spectrum sharing efficiency and poor performance between cellular users and Internet of Things sensors.

[0004] In order to solve the above technical problems, the present invention is implemented by adopting the following technical solutions:

[0005] On the one hand, the present invention provides a cellular Internet of Things relay NOMA transmission method, comprising:

[0006] Sending a first radio frequency NOMA signal to an IoT signal end and a signal relay end predetermined according to a signal transmitting end and a target IoT cluster channel power;

[0007] receiving a second radio frequency NOMA signal sent by the signal relay end;

[0008] Receive a first reflected signal loaded with Internet of Things information based on a first radio frequency NOMA signal and a second reflected signal loaded with Internet of Things information based on a second radio frequency NOMA signal sent by an Internet of Things signal terminal;

[0009] The Internet of Things information of the Internet of Things signal end is determined according to the first reflected signal, the second reflected signal and the second radio frequency NOMA signal.

[0010] Furthermore, the IoT signal end predetermined according to the signal transmitting end and the target IoT cluster channel power includes:

[0011] Taking the maximum channel power between the signal transmitting end and the IoT signal end in the target IoT cluster as the criterion, determine the IoT signal end with the maximum channel power in the target IoT cluster:

[0012] ;

[0013] in: Indicates the IoT signal end with the largest channel power. V represents the target IoT cluster, v i Indicates the number of i IoT signal terminals, Indicates the signal sending end to the IoT signal end v i The channel coefficients, Indicates the signal sending end to the IoT signal end v i The channel power, M Indicates the number of IoT signal terminals in the target IoT cluster.

[0014] Further, determining the IoT information of the IoT signal end according to the first reflected signal, the second reflected signal, and the second radio frequency NOMA signal includes:

[0015] Acquire a first received signal according to the first reflected signal;

[0016] Acquire a second received signal according to the second reflected signal and the second radio frequency NOMA signal;

[0017] The Internet of Things information of the Internet of Things signal end is analyzed respectively according to the first received signal and the second received signal.

[0018] Furthermore, obtaining the first received signal according to the first reflected signal includes: obtaining the first received signal by calculating using the following formula:

[0019] ;

[0020] in: ( q ) represents a first received signal, represents the first radio frequency NOMA signal, q Indicates the signal index number, represents the first reflection signal, Represents the channel coefficient from the signal sending end to the IoT signal end, Represents the first reflection coefficient of the IoT signal end, , Indicates the IoT information loaded by the IoT signal end based on the first radio frequency NOMA signal. represents the self-interference channel at the signal transmitter, represents the residual interference coefficient of the self-interference elimination at the signal transmitting end, , Represents the first additive white Gaussian noise at the signal transmitting end.

[0021] Furthermore, obtaining the second received signal according to the second reflected signal and the second RF NOMA signal includes: obtaining the second received signal by calculating using the following formula:

[0022] ;

[0023] in: ( q ) represents the second received signal, represents the second radio frequency NOMA signal, q Indicates the signal index number, represents the second reflected signal, Indicates the channel coefficient from the signal relay end to the IoT signal end, It represents the channel coefficient from the IoT signal end to the signal sending end. Represents the second reflection coefficient of the IoT signal end, , Indicates the IoT information loaded by the IoT signal end based on the second radio frequency NOMA signal. It represents the channel coefficient from the signal relay end to the signal sending end. Represents the second additive white Gaussian noise at the signal transmitting end.

[0024] A second aspect of the present invention provides a cellular Internet of Things relay NOMA transmission method, including:

[0025] A first radio frequency NOMA signal sent by a receiving signal transmitting end and a first reflected signal based on information loaded by the first radio frequency NOMA signal sent by an IoT signal end;

[0026] Generate a second RF NOMA signal according to the first RF NOMA signal and the first reflected signal;

[0027] A second radio frequency NOMA signal is sent to an edge user terminal, an Internet of Things signal terminal, and a signal sending terminal that are predetermined according to the channel power of the signal sending terminal and the target user terminal cluster.

[0028] Further, the edge user end predetermined according to the channel power of the signal transmitting end and the target user end cluster includes:

[0029] Taking the maximum channel power between the signal transmitter and the user end in the target user end cluster as the criterion, select the edge user end with the maximum channel power:

[0030] ;

[0031] in: Indicates the edge user end with the largest channel power, U Indicates the target user cluster, u j Indicates the number of j A user terminal, Indicates the signal sending end to the user end u j The channel coefficients, Indicates the signal sending end to the user end u j The channel power, N Indicates the number of clients in the target client cluster;

[0032] Taking the minimum channel power between the signal transmitter and the user end in the target user end cluster as the criterion, select the edge user end with the minimum channel power:

[0033] ;in: Indicates the edge user end with the smallest channel power.

[0034] Further, generating a second RF NOMA signal according to the first RF NOMA signal and the first reflected signal includes:

[0035] Acquire a relay reception signal according to the first radio frequency NOMA signal and the first reflected signal;

[0036] The first reflected signal is used as a multipath link of the first radio frequency NOMA signal, and the relay received signal is decoded to obtain the information required by the edge user end;

[0037] The information required by the edge user end is encoded to generate a second RF NOMA signal.

[0038] Furthermore, obtaining the relay reception signal according to the first radio frequency NOMA signal and the first reflected signal includes: obtaining the relay reception signal by calculating using the following formula:

[0039] ;

[0040] in: Indicates that the relay receives the signal. represents the channel coefficient from the signal transmitter to the signal relay end, Indicates the channel coefficient from the IoT signal end to the signal relay end, represents the first radio frequency NOMA signal, Represents the channel coefficient from the signal sending end to the IoT signal end, Represents the first reflection coefficient of the IoT signal end, , represents the first reflection signal, Indicates the IoT information loaded by the IoT signal end based on the first radio frequency NOMA signal. Represents the additive white Gaussian noise at the signal relay end.

[0041] The present invention also provides a cellular Internet of Things relay NOMA transmission system, comprising: a signal sending end, a target Internet of Things cluster, a signal relay end and a target user end cluster;

[0042] The signal transmitting end sends a first radio frequency NOMA signal to an IoT signal end and a signal relay end that are predetermined according to the channel power between the signal transmitting end and the target IoT cluster;

[0043] The signal relay end receives the first RF NOMA signal sent by the signal transmitting end and the first reflected signal based on the first RF NOMA signal loading information sent by the IoT signal end. The signal relay end generates a second RF NOMA signal according to the first RF NOMA signal and the first reflected signal, and sends the second RF NOMA signal to the edge user end, the IoT signal end, and the signal transmitting end predetermined according to the channel power between the signal transmitting end and the target user end cluster;

[0044] The signal transmitting end receives the second radio frequency NOMA signal sent by the signal relay end, and receives the first reflected signal loaded with the Internet of Things information based on the first radio frequency NOMA signal and the second reflected signal loaded with the Internet of Things information based on the second radio frequency NOMA signal sent by the Internet of Things signal end;

[0045] The signal transmitting end determines the Internet of Things information of the Internet of Things signal end according to the first reflected signal, the second reflected signal and the second radio frequency NOMA signal.

[0046] Compared with the prior art, the present invention has the following beneficial effects:

[0047] 1. In the present invention, the IoT signal end uses the first RF NOMA signal sent by the signal transmitting end to load its own IoT information and generate a first reflected signal. The first reflected signal is received by the signal transmitting end and the signal relay end respectively. The signal relay end obtains the information required by the edge user end according to the first reflected signal and the first RF NOMA signal, and encodes the information required by the edge user end to generate a second RF NOMA signal for transmission. The edge user receives the second RF NOMA signal to obtain the information required by itself. At the same time, the IoT signal end uses the second RF NOMA signal again to load its own IoT information to generate a second reflected signal. The second reflected signal and the second RF NOMA signal are received by the signal transmitting end. The signal transmitting end can determine the IoT information of the IoT signal end according to the received signal. The edge user and the IoT signal end share the spectrum during the entire signal transmission process, and the signal relay end and the reflected signal are used to reduce energy consumption while expanding the signal coverage range, thereby solving the problem of low efficiency and poor performance of spectrum sharing between current cellular users and IoT sensors.

[0048] 2. The signal relay end of the present invention uses the first reflected signal as a multipath link of the first RF NOMA signal to improve its own decoding signal-to-interference-noise ratio, decodes the relay received signal, and obtains the information required by the edge user end and its own information.

[0049] 3. The present invention predetermines the IoT signal end and the edge user end according to the channel power between the signal sending end and the target IoT cluster and the target user end cluster, and reduces the complexity of information processing at each signal end by selecting the IoT signal end with the largest channel power, the edge user end with the largest channel power and the edge user end with the smallest channel power to participate in signal transmission. BRIEF DESCRIPTION OF THE DRAWINGS

[0050] Figure 1 It is an embodiment of a cellular Internet of Things relay NOMA transmission method and system of the present invention, a flow chart of a cellular Internet of Things relay NOMA transmission method at the signal sending end;

[0051] Figure 2 It is an embodiment of a cellular Internet of Things relay NOMA transmission method and system of the present invention, a flow chart of a cellular Internet of Things relay NOMA transmission method at a signal relay end;

[0052] Figure 3 It is an embodiment of a cellular Internet of Things relay NOMA transmission method and system of the present invention, a spectrum efficiency comparison diagram of a cellular Internet of Things relay NOMA transmission method, a traditional NOMA method, and an orthogonal multiple access (OMA) method;

[0053] Figure 4It is an embodiment of a cellular Internet of Things relay NOMA transmission method and system of the present invention. A spectrum efficiency comparison diagram of a cellular Internet of Things relay NOMA transmission method, a traditional NOMA method, and an orthogonal multiple access (OMA) method using different node schemes;

[0054] Figure 5 It is an embodiment of a cellular Internet of Things relay NOMA transmission method and system of the present invention, a comparison diagram of the overall system spectrum efficiency of a cellular Internet of Things relay NOMA transmission method and a non-symbiotic method;

[0055] Figure 6 It is an embodiment of a cellular Internet of Things relay NOMA transmission method and system of the present invention, a spectrum efficiency comparison diagram of edge user terminal information transmission of a cellular Internet of Things relay NOMA transmission method and a non-symbiotic method;

[0056] Figure 7 It is an embodiment of a cellular Internet of Things relay NOMA transmission method and system of the present invention, a spectrum efficiency comparison diagram of information transmission of the Internet of Things signal end of a cellular Internet of Things relay NOMA transmission method and a non-symbiotic method;

[0057] Figure 8 It is an embodiment of a cellular Internet of Things relay NOMA transmission method and system of the present invention, and a curve chart showing the energy efficiency multiples of the cellular Internet of Things relay NOMA transmission method and other methods as the transmission signal-to-noise ratio changes. DETAILED DESCRIPTION

[0058] The present invention will be further described below in conjunction with the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present invention, and cannot be used to limit the protection scope of the present invention. Example

[0059] like Figure 1 and Figure 2 As shown, a cellular Internet of Things relay NOMA transmission method includes:

[0060] The signal transmitting end transmits a first radio frequency NOMA signal to a predetermined IoT signal end and a signal relay end;

[0061] Among them, the predetermined IoT signal terminals include:

[0062] Determine the IoT signal end from the target IoT cluster. Specifically, the IoT signal end in this embodiment is an IoT sensor. The IoT signal end with the largest channel power in the target IoT cluster is determined based on the maximum channel power between the signal transmitting end and the IoT signal end in the target IoT cluster:

[0063] ; Indicates the IoT signal end with the maximum channel power. V represents the target IoT cluster, v i Indicates the number of i IoT signal terminals, Indicates the signal sending end to the IoT signal end v i The channel coefficients, Indicates the signal sending end to the IoT signal end v i The channel power, M Indicates the number of IoT signal terminals in the target IoT cluster;

[0064] The IoT signal end receives the first radio frequency NOMA signal, uses backscatter modulation to load its own IoT information onto a portion of the first radio frequency NOMA signal to generate a first reflected signal, sends the first reflected signal, and uses the remaining portion of the first radio frequency NOMA signal as self-use energy;

[0065] The signal transmitting end receives the first reflected signal.

[0066] The signal relay end receives the first radio frequency NOMA signal and the first reflected signal and generates a second radio frequency NOMA signal according to the first radio frequency NOMA signal and the first reflected signal. Specifically:

[0067] The signal relay end obtains the relay reception signal according to the first radio frequency NOMA signal and the first reflected signal, including: obtaining the relay reception signal by calculating using the following formula:

[0068] ;in: Indicates that the relay receives the signal. represents the channel coefficient from the signal transmitter to the signal relay end, Indicates the channel coefficient from the IoT signal end to the signal relay end, represents the first radio frequency NOMA signal, q Indicates the signal index number, , Q It represents the ratio of IoT signal cycle length to cellular signal cycle length. Represents the channel coefficient from the signal sending end to the IoT signal end, Represents the first reflection coefficient of the IoT signal end, , represents the first reflection signal, Indicates the IoT information loaded by the IoT signal end based on the first radio frequency NOMA signal. represents the additive white Gaussian noise at the signal relay end;

[0069] The first reflected signal is used as a multipath link of the first radio frequency NOMA signal, and the relay received signal is decoded to obtain the predetermined information required by the edge user end and the signal relay end. Specifically:

[0070] ;

[0071] in: Indicates the transmission power of the signal transmitter. , and Carry predetermined edge user terminals respectively , predetermined edge user end and the information required by the signal relay end; Indicates signal The first power allocation coefficient, Indicates signal The first power allocation coefficient, Indicates signal The first power allocation coefficient, and press the next NOMA The criteria are set to , ;

[0072] The signal relay terminal presses the down NOMA Principle, using serial interference cancellation algorithm to decode the signal in sequence , the corresponding signal to interference noise ratio can be expressed as:

[0073]

[0074] in: Indicates the decoded signal The signal-to-interference-noise ratio, Indicates the decoded signal The signal-to-interference-noise ratio, Indicates the decoded signal Signal-to-interference-noise ratio; represents the signal-to-noise ratio at the signal sending end, , represents the noise power; represents the composite channel power, ; Indicates that the signal relay end is eliminating the signal The residual interference strength due to imperfect serial interference cancellation is ; Indicates that the signal relay end is eliminating the signal The residual interference strength due to imperfect serial interference cancellation is .

[0075] The pre-determined edge users include:

[0076] Select an edge user end from the target user end cluster. In this example, the edge user end with the largest channel power is selected based on the criterion that the channel power between the signal transmitter and the user end in the target user end cluster is the largest:

[0077] ;

[0078] in: Indicates the edge user end with the largest channel power, U Indicates the target user cluster, u j Indicates the number of j A user terminal, Indicates the signal sending end to the user end u j The channel coefficients, Indicates the signal sending end to the user end u j The channel power, N Indicates the number of clients in the target client cluster;

[0079] Taking the minimum channel power between the signal transmitter and the user end in the target user end cluster as the criterion, select the edge user end with the minimum channel power:

[0080] ;

[0081] in: Indicates the edge user end with the smallest channel power.

[0082] Encode the information required by the edge user end to generate the second RF NOMA signal :

[0083] ;

[0084] in: Indicates signal The second power allocation coefficient, Indicates signal The second power allocation coefficient is , and the following NOMA principle is satisfied: , ;

[0085] The signal relay end sends a second radio frequency NOMA signal to a predetermined edge user end, an IoT signal end, and a signal sending end.

[0086] Marginal users and marginal users Receive the second radio frequency NOMA signal respectively , and decode the required signals according to the following NOMA criteria, specifically:

[0087] The signal received by the edge user based on the second radio frequency NOMA signal is calculated according to the following formula:

[0088] ;

[0089] The signal received by the edge user based on the second radio frequency NOMA signal is calculated according to the following formula:

[0090] ;

[0091] in: Indicates marginal users According to the signal received by the second radio frequency NOMA signal, Indicates marginal users According to the signal received by the second radio frequency NOMA signal, Indicates marginal users Additive Gaussian white noise, Indicates marginal users Additive Gaussian white noise;

[0092] Marginal users The signals are decoded sequentially using the serial interference cancellation algorithm and , the corresponding signal to interference noise ratio can be expressed as:

[0093] ;

[0094] ;

[0095] in: Indicates marginal users Decoding the signal The signal-to-interference-noise ratio, Indicates marginal users Decoding the signal Signal-to-interference-noise ratio; Indicates marginal users Eliminating the signal The residual interference strength due to imperfect serial interference cancellation is ;

[0096] Marginal users Treating Signals as Interference , directly decode the signal , the corresponding signal to interference noise ratio can be expressed as:

[0097] ;

[0098] in: Indicates marginal users Decoding the signal signal-to-interference-noise ratio.

[0099] The IoT signal end uses backscatter modulation to load its own IoT information onto a portion of the second radio frequency NOMA signal to generate a second reflected signal and send the second reflected signal, and uses the remaining portion of the second radio frequency NOMA signal as its own energy;

[0100] The signal transmitting end receives the second radio frequency NOMA signal and the second reflected signal;

[0101] The signal transmitting end determines the IoT information of the IoT signal end according to the first reflected signal, the second reflected signal and the second radio frequency NOMA signal, specifically:

[0102] Acquiring a first received signal according to the first reflected signal includes: obtaining the first received signal by calculating using the following formula:

[0103] ;

[0104] in: ( q ) represents a first received signal, represents the first radio frequency NOMA signal, represents the first reflection signal, Represents the channel coefficient from the signal sending end to the IoT signal end, Represents the first reflection coefficient of the IoT signal end, , Indicates the IoT information loaded by the IoT signal end based on the first radio frequency NOMA signal. represents the self-interference channel at the signal transmitter, represents the residual interference coefficient of the self-interference elimination at the signal transmitting end, represents the first additive white Gaussian noise of the signal transmitting end;

[0105] Obtaining a second received signal according to the second reflected signal and the second radio frequency NOMA signal includes: obtaining the second received signal by calculating using the following formula:

[0106] ;

[0107] in: ( q ) represents the second received signal, represents the second radio frequency NOMA signal, represents the second reflected signal, Indicates the channel coefficient from the signal relay end to the IoT signal end, It represents the channel coefficient from the IoT signal end to the signal sending end. Represents the second reflection coefficient of the IoT signal end, , Indicates the IoT information loaded by the IoT signal end based on the second radio frequency NOMA signal. It represents the channel coefficient from the signal relay end to the signal sending end. represents the second additive white Gaussian noise at the signal transmitting end;

[0108] According to the first received signal and the second received signal, respectively, the IoT information of the IoT signal end is parsed;

[0109] Analyze the IoT information loaded by the IoT signal end based on the first radio frequency NOMA signal The dryness ratio includes:

[0110]

[0111] in: Indicates the IoT information loaded by the IoT signal end based on the first radio frequency NOMA signal The letter drying ratio, Indicates the channel gain from the signal sending end to the IoT signal end, , represents the self-interference channel gain at the signal transmitting end, ;

[0112] Analyze the IoT information loaded by the IoT signal end based on the second radio frequency NOMA signal The signal-to-interference-noise ratio includes:

[0113] ;

[0114] in: Indicates the IoT information loaded by the IoT signal end based on the second radio frequency NOMA signal The letter drying ratio, Indicates the signal-to-noise ratio at the signal relay end. , Indicates the transmit power of the signal relay end.

[0115] Calculate the overall spectral efficiency of signal transmission :

[0116] ;

[0117] Calculate the spectrum efficiency of edge user information transmission :

[0118] ;

[0119] Calculating the spectral efficiency of information transmission at the IoT signal end :

[0120] ;

[0121] like Figure 3 As shown, the transmission method provided by this example has a spectrum efficiency advantage over the traditional NOMA method and the orthogonal multiple access (OMA) method in the ideal SIC and non-ideal SIC cases, because in the traditional NOMA method, the base station only uses downlink NOMA to serve two edge users in two stages, and does not consider the relay node receiving information and the spectrum sharing between cellular users and sensors, resulting in low spectrum efficiency; in addition, the OMA method uses time division multiple access to transmit the signal in the proposed method in seven stages, which has low spectrum efficiency due to its own resource orthogonality. For example: in the ideal SI Under C conditions, when the transmission signal-to-noise ratio is 30 dB, the spectrum efficiency of the transmission method provided by the example of the present invention is 5.374 bps / Hz, while the spectrum efficiencies of the traditional NOMA method and the OMA method are 2.528 bps / Hz and 3.068 bps / Hz, respectively. Under non-ideal SIC conditions, when the transmission signal-to-noise ratio is 40 dB, the spectrum efficiency of the transmission method provided by the example of the present invention is 6.828 bps / Hz, while the spectrum efficiencies of the traditional NOMA method and the OMA method are 2.055 bps / Hz and 4.5 bps / Hz, respectively.

[0122] like Figure 4 As shown, the transmission method provided by this example has spectrum efficiency advantages under ideal SIC and non-ideal SIC conditions compared with the traditional NOMA method and orthogonal multiple access (OMA) method. The sensor nodes and two edge user nodes representing the information transmission are randomly selected from the corresponding clusters. The NOMA technology achieves high spectrum efficiency advantages by means of differences in channel quality and power allocation between users, and the above differences can be better guaranteed in the node selection scheme based on channel power sorting. For example: under ideal SIC conditions, when the transmission signal-to-noise ratio is 40dB, the transmission method provided by this example uses sorting selection with a spectrum efficiency of 7.485bps / Hz, while the spectrum efficiency of random selection is 7.105bps / Hz. Under non-ideal SIC conditions, when the transmission signal-to-noise ratio is 40dB, the transmission method provided by this example uses sorting selection with a spectrum efficiency of 7.253bps / Hz, while the spectrum efficiency of random selection is 7.039bps / Hz.

[0123] like Figure 5 , Figure 6 and Figure 7As shown, the non-symbiotic method represents that no IoT sensors participate in information transmission, and the information transmission process of cellular users is consistent with the cellular user information transmission in the proposed method. Compared with the overall system of the non-symbiotic method, the transmission method provided in this example introduces IoT sensors in the transmission method provided in this example, which can complete the information service function of IoT sensors without consuming additional spectrum resources and time resources, thereby improving the overall system spectrum efficiency. At the same time, the introduction of IoT sensors adds a beneficial multipath to the relay node, which can enhance the decoding signal-to-interference-noise ratio of the relay node, thereby improving the spectrum efficiency of the cellular subsystem. The transmission method provided in this example can achieve higher overall system spectrum efficiency, cellular subsystem spectrum efficiency and IoT subsystem spectrum efficiency than the non-symbiotic method under both ideal SIC and non-ideal SIC conditions;

[0124] like Figure 8 As shown, the transmission method provided by this example has an energy efficiency advantage over the traditional NOMA method and the orthogonal multiple access (OMA) method in the ideal SIC and non-ideal SIC cases. Since the transmission method provided by this example and the traditional NOMA method consume the same energy but can achieve higher spectrum efficiency, the energy efficiency of the transmission method provided by this example is higher than that of the traditional NOMA method.

[0125] In addition, since the relay transmission power is usually smaller than the base station transmission power, the OMA method consumes more energy than the transmission method provided in this example, but the spectrum efficiency is relatively low. Therefore, the energy efficiency of the transmission method provided in this example is higher than that of the OMA method. For example, under ideal SIC conditions, when the transmission signal-to-noise ratio is 40dB, the energy efficiency of the transmission method provided by this example is 1.739 times and 1.857 times that of the traditional NOMA method and the OMA method, respectively; under non-ideal SIC conditions, when the transmission signal-to-noise ratio is 40dB, the energy efficiency of the transmission method provided by this example is 3.323 times and 1.694 times that of the traditional NOMA method and the OMA method, respectively. Example

[0126] A cellular Internet of Things relay NOMA transmission system, comprising: a signal sending end, a target Internet of Things cluster, a signal relay end and a target user end cluster;

[0127] The signal transmitting end sends a first radio frequency NOMA signal to an IoT signal end and a signal relay end that are predetermined according to the channel power between the signal transmitting end and the target IoT cluster;

[0128] The signal relay end receives the first RF NOMA signal sent by the signal transmitting end and the first reflected signal based on the first RF NOMA signal loading information sent by the IoT signal end. The signal relay end generates a second RF NOMA signal according to the first RF NOMA signal and the first reflected signal, and sends the second RF NOMA signal to the edge user end, the IoT signal end, and the signal transmitting end predetermined according to the channel power between the signal transmitting end and the target user end cluster;

[0129] The signal transmitting end receives the second radio frequency NOMA signal sent by the signal relay end, and receives the first reflected signal loaded with the Internet of Things information based on the first radio frequency NOMA signal and the second reflected signal loaded with the Internet of Things information based on the second radio frequency NOMA signal sent by the Internet of Things signal end;

[0130] The signal transmitting end determines the Internet of Things information of the Internet of Things signal end according to the first reflected signal, the second reflected signal and the second radio frequency NOMA signal.

[0131] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the technical principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A cellular Internet of Things relay NOMA transmission method, characterized in that: include: The signal transmitting end sends a first radio frequency NOMA signal to an IoT signal end and a signal relay end that are predetermined according to the channel power between the signal transmitting end and the target IoT cluster; The signal relay end receives a first radio frequency NOMA signal sent by the signal transmitting end and a first reflected signal based on the first radio frequency NOMA signal loading information sent by the IoT signal end; The signal relay end generates a second radio frequency NOMA signal according to the first radio frequency NOMA signal and the first reflected signal; The signal relay end sends a second radio frequency NOMA signal to an edge user end, an IoT signal end, and a signal sending end that are predetermined according to the channel power of the signal sending end and the target user end cluster; The signal transmitting end receives a second radio frequency NOMA signal sent by the signal relay end; The signal transmitting end receives a first reflected signal loaded with Internet of Things information based on the first radio frequency NOMA signal and a second reflected signal loaded with Internet of Things information based on the second radio frequency NOMA signal, which are sent by the Internet of Things signal end; The signal transmitting end determines the Internet of Things information of the Internet of Things signal end according to the first reflected signal, the second reflected signal and the second radio frequency NOMA signal.

2. The cellular Internet of Things relay NOMA transmission method according to claim 1, characterized in that: The IoT signal end predetermined according to the signal transmitting end and the target IoT cluster channel power includes: Taking the maximum channel power between the signal transmitting end and the IoT signal end in the target IoT cluster as the criterion, determine the IoT signal end with the maximum channel power in the target IoT cluster: ； in: Indicates the IoT signal end with the largest channel power. V represents the target IoT cluster, v i Indicates the number of i IoT signal terminals, Indicates the signal sending end to the IoT signal end v i The channel coefficients, Indicates the signal sending end to the IoT signal end v i The channel power, M Indicates the number of IoT signal terminals in the target IoT cluster.

3. The cellular Internet of Things relay NOMA transmission method according to claim 1, characterized in that: The determining the IoT information of the IoT signal end according to the first reflected signal, the second reflected signal and the second radio frequency NOMA signal includes: Acquire a first received signal according to the first reflected signal; Acquire a second received signal according to the second reflected signal and the second radio frequency NOMA signal; The Internet of Things information of the Internet of Things signal end is analyzed respectively according to the first received signal and the second received signal.

4. The cellular Internet of Things relay NOMA transmission method according to claim 3 is characterized in that: The step of obtaining the first received signal according to the first reflected signal includes: obtaining the first received signal by calculating using the following formula: ； in: ( q ) represents a first received signal, represents the first radio frequency NOMA signal, q Indicates the signal index number, represents the first reflected signal, Represents the channel coefficient from the signal sending end to the IoT signal end, Represents the first reflection coefficient of the IoT signal end, , Indicates the IoT information loaded by the IoT signal end based on the first radio frequency NOMA signal. represents the self-interference channel at the signal transmitter, represents the residual interference coefficient of the self-interference elimination at the signal transmitting end, , Represents the first additive white Gaussian noise at the signal transmitting end.

5. The cellular Internet of Things relay NOMA transmission method according to claim 3, characterized in that: The obtaining of the second received signal according to the second reflected signal and the second radio frequency NOMA signal includes: obtaining the second received signal by calculating using the following formula: ； in: ( q ) represents the second received signal, represents the second radio frequency NOMA signal, q Indicates the signal index number, represents the second reflected signal, Indicates the channel coefficient from the signal relay end to the IoT signal end, It represents the channel coefficient from the IoT signal end to the signal sending end. Represents the second reflection coefficient of the IoT signal end, , Indicates the IoT information loaded by the IoT signal end based on the second radio frequency NOMA signal. It represents the channel coefficient from the signal relay end to the signal sending end. Represents the second additive white Gaussian noise at the signal transmitting end.

6. The cellular Internet of Things relay NOMA transmission method according to claim 1, characterized in that: The edge user end predetermined according to the channel power of the signal transmitting end and the target user end cluster includes: Taking the maximum channel power between the signal transmitter and the user end in the target user end cluster as the criterion, select the edge user end with the maximum channel power: ； in: Indicates the edge user end with the largest channel power, U Indicates the target user cluster, u j Indicates the number of j A user terminal, Indicates the signal sending end to the user end u j The channel coefficients, Indicates the signal sending end to the user end u j The channel power, N Indicates the number of clients in the target client cluster; Taking the minimum channel power between the signal transmitter and the user end in the target user end cluster as the criterion, select the edge user end with the minimum channel power: ； in: Indicates the edge user end with the smallest channel power.

7. The cellular Internet of Things relay NOMA transmission method according to claim 1, characterized in that: The step of generating a second radio frequency NOMA signal according to the first radio frequency NOMA signal and the first reflected signal includes: Acquire a relay reception signal according to the first radio frequency NOMA signal and the first reflected signal; The first reflected signal is used as a multipath link of the first radio frequency NOMA signal, and the relay received signal is decoded to obtain the information required by the edge user end; The information required by the edge user end is encoded to generate a second RF NOMA signal.

8. The cellular Internet of Things relay NOMA transmission method according to claim 7, characterized in that: The step of obtaining the relay reception signal according to the first radio frequency NOMA signal and the first reflected signal includes: obtaining the relay reception signal by calculating using the following formula: ； in: Indicates that the relay receives the signal. represents the channel coefficient from the signal transmitter to the signal relay end, Indicates the channel coefficient from the IoT signal end to the signal relay end, represents the first radio frequency NOMA signal, Represents the channel coefficient from the signal sending end to the IoT signal end, Represents the first reflection coefficient of the IoT signal end, , represents the first reflection signal, Indicates the IoT information loaded by the IoT signal end based on the first radio frequency NOMA signal. Represents the additive white Gaussian noise at the signal relay end.

9. A cellular Internet of Things relay NOMA transmission system, characterized in that: include: Signal sending end, target IoT cluster, signal relay end and target user end cluster; The signal transmitting end sends a first radio frequency NOMA signal to an IoT signal end and a signal relay end that are predetermined according to the channel power between the signal transmitting end and the target IoT cluster; The signal relay end receives the first RF NOMA signal sent by the signal transmitting end and the first reflected signal based on the first RF NOMA signal loading information sent by the IoT signal end. The signal relay end generates a second RF NOMA signal according to the first RF NOMA signal and the first reflected signal, and sends the second RF NOMA signal to the edge user end, the IoT signal end, and the signal transmitting end predetermined according to the channel power between the signal transmitting end and the target user end cluster; The signal transmitting end receives the second radio frequency NOMA signal sent by the signal relay end, and receives the first reflected signal loaded with the Internet of Things information based on the first radio frequency NOMA signal and the second reflected signal loaded with the Internet of Things information based on the second radio frequency NOMA signal sent by the Internet of Things signal end; The signal transmitting end determines the Internet of Things information of the Internet of Things signal end according to the first reflected signal, the second reflected signal and the second radio frequency NOMA signal.

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