Signal transmitting and receiving method and device based on reconfigurable refractive metasurface

Abstract

The application discloses a signal transmitting and receiving method and device based on a reconfigurable refractive metasurface, the method comprising: sending a first pilot sequence to a user, and feeding back the received signal by the user; receiving the feedback of the first pilot sequence by the user, and estimating the channel between the feed source and the reconfigurable refractive metasurface, the channel between the reconfigurable refractive metasurface and the user, the incident angle of the feed source to each unit of the reconfigurable refractive metasurface, and the exit angle of each unit of the reconfigurable refractive metasurface to the user based on the feedback; designing the state of each unit of the reconfigurable refractive metasurface in the data transmitting and receiving stage according to the channel, the exit angle and the incident angle; and transmitting and receiving data based on the designed state of the reconfigurable refractive metasurface. The application can accurately estimate the response of the RRS unit, thereby improving the performance of the RRS antenna beam forming, and improving the system data transmission rate.

Description

Technical Field

[0001] This invention relates to the field of electronics, specifically to a signal transmission and reception method and apparatus based on a reconfigurable refractive metasurface. Background Technology

[0002] To realize ubiquitous intelligent information networks, the upcoming sixth-generation (6G) wireless communication requires signal transmitting and receiving devices with beamforming capabilities. Traditional phased array-based signal transmitters are one type of signal transmitter with beamforming capabilities. However, traditional phased arrays suffer from high power consumption and high cost. To address this issue, signal transmitters based on reconfigurable reflective metasurface antennas have recently been proposed. However, this transmitter has the following drawback: for the reconfigurable reflective metasurface antenna in the device, the feed source can block the reflected waves, resulting in low antenna radiation efficiency. Therefore, signal transmitters based on reconfigurable refractive metasurface (RRS) antennas have been proposed. Since reconfigurable refractive metasurfaces do not have the problem of feed source blocking, their radiation efficiency is higher than that of traditional reconfigurable reflective metasurface antennas.

[0003] Existing transceivers using metamaterial antennas do not consider the impact of incident and exit angles on the response of metamaterial elements during beamforming; they simply perform beamforming based on the responses of metamaterial elements at normal incidence and exit. However, the response of the RRS element is affected by the incident and exit angles. Therefore, using the existing architecture will lead to incorrect estimation of the RRS element response, further resulting in a degraded beamforming performance. Summary of the Invention

[0004] To address the problem that existing transceiver architectures using metamaterial antennas do not consider the influence of incident and exit angles on the response of metamaterial elements, leading to incorrect estimation of the RRS element response and further degrading the beamforming performance of the RRS antenna, this invention provides a signal transmission method and apparatus based on a reconfigurable refractive metasurface. This invention improves the system data transmission rate by introducing incident and exit angle estimation modules into the architecture and designing corresponding signal transmission and reception procedures.

[0005] To achieve the above technical objectives, the technical solution of the present invention includes:

[0006] A signal transmission and reception method based on a reconfigurable refractive metasurface antenna is provided, applied to a signal transmission and reception device based on a reconfigurable refractive metasurface antenna. The reconfigurable refractive metasurface antenna includes a feed source and a reconfigurable refractive metasurface. The method includes:

[0007] 1) Send the first pilot sequence to the user, who then provides feedback on the received signal;

[0008] 2) Receive feedback from the user on the first pilot sequence, and based on the feedback, estimate the channel h between the feed and the reconfigurable refractive metasurface. F,(m,n) The channel h between the reconfigurable refractive metasurface and the user (m,m),U The incident angle θ′ of the feed source to each unit of the reconfigurable refractive metasurface (m,n) The exit angle θ from each unit of the reconfigurable refractive metasurface to the user (m,n) , where m is the row number of the cell and n is the column number of the cell;

[0009] 3) According to the channel h F,(m,n) and h (m,n),U , emission angle θ (m,n) Angle of incidence θ′ (m,n) The state of each unit of the reconfigurable refractive metasurface during the data transmission and reception phases is designed.

[0010] 4) Data is sent and received based on the state of the designed reconfigurable refractive metasurface.

[0011] Further, sending the first pilot sequence to the user includes:

[0012] 1) The baseband unit processes the first pilot sequence;

[0013] 2) The processed signal is converted into an analog signal by the digital-to-analog converter unit;

[0014] 3) The analog signal is converted into a radio frequency signal via a transmission radio frequency link;

[0015] 4) The radio frequency signal is emitted using the reconfigurable refractive metasurface antenna, while the first beamforming is performed.

[0016] Furthermore, receiving user feedback on the first pilot sequence includes:

[0017] 1) Use the reconfigurable refractive metasurface antenna to receive user feedback on the first pilot sequence;

[0018] 2) Use a receiving radio frequency link to convert the received signal into an analog signal;

[0019] 3) The analog signal is converted into a digital signal by an analog-to-digital converter.

[0020] 4) The digital signal is processed by the baseband unit.

[0021] Furthermore, the design can reconstruct the state of each unit of the refractive metasurface during the data transmission phase, including:

[0022] 1) Model the relationship between the state of each unit and the data transmission rate;

[0023] 2) Adjust the status of each unit to maximize the data transmission rate.

[0024] Furthermore, the modeling of the relationship between the state of each unit and the data transmission rate includes:

[0025] 1) Based on the state of the cell during the data transmission phase, the incident angle from the feed to the cell, the exit angle from the cell to the user, the channel between the feed and the cell and the channel between the cell and the user, calculate the gain of the (m,n)th metasurface-based channel.

[0026] 2) Calculate the channel h between the feed and the user based on the channel gain. Tx ;

[0027] 3) Based on the channel h Tx The user's received signal-to-noise ratio is obtained by taking the variance of the feed's transmit power and the additive white Gaussian noise received by the user.

[0028] 4) Based on the received signal-to-noise ratio, model the relationship between the state of each unit and the data transmission rate.

[0029] Furthermore, the design can reconstruct the state of each unit of the refractive metasurface during the data reception phase, including:

[0030] 1) Model the relationship between the state of each unit and the rate of data reception;

[0031] 2) Adjust the status of each unit to maximize the data reception rate.

[0032] Furthermore, the modeling of the relationship between the state of each unit and the rate of data reception includes:

[0033] 1) Based on the state of the cell during the data reception phase, the incident angle from the feed to the cell, the exit angle from the cell to the user, the channel between the feed and the cell and the channel between the cell and the user, calculate the gain of the (m,n)th metasurface-based channel.

[0034] 2) Calculate the channel h between the feed and the user based on the channel gain. Rx ;

[0035] 3) Based on the channel h Rx The user's transmit power and the variance of the additive white Gaussian noise received by the transceiver are used to obtain the received signal-to-noise ratio of the transceiver.

[0036] 4) Based on the received signal-to-noise ratio, model the relationship between the state of each unit and the received data rate.

[0037] A storage medium storing a computer program, wherein the computer program is configured to execute the method described above at runtime.

[0038] A signal transmitting and receiving device based on a reconfigurable refractive metasurface antenna, the reconfigurable refractive metasurface antenna comprising: a feed source and a reconfigurable refractive metasurface, the signal transmitting and receiving device comprising:

[0039] The signal transmission module is used to send the first pilot sequence and data signals to the user;

[0040] The signal receiving module is used to receive the user's feedback on the first pilot sequence, the second pilot sequence sent by the user, and the data signal sent by the user, respectively.

[0041] The channel estimation module is used to estimate the channel h between the feed source and the reconfigurable refractive metasurface based on the received user feedback on the first pilot sequence. F,(m,n) The channel h between the reconfigurable refractive metasurface and the user (m,n),U Where m is the row number of the cell and n is the column number of the cell;

[0042] The incident angle and exit angle estimation module is used to estimate the incident angle θ′ from the feed source to each unit of the reconfigurable refractive metasurface based on the received user feedback on the first pilot sequence. (m,n) The exit angle θ from each unit of the reconfigurable refractive metasurface to the user (m,n) , where m is the row number of the cell and n is the column number of the cell;

[0043] The reconfigurable refractive metasurface state design module is used to design the state of the reconfigurable refractive metasurface based on the channel h. F,(m,n) and h (m,n),U , emission angle θ (m,n) Angle of incidence θ′ (m,n) The state of each unit of the reconfigurable refractive metasurface during the data transmission and reception phases is designed.

[0044] Compared with existing technologies, the present invention has the following advantages: it enables accurate channel estimation, thereby improving the performance of RRS antenna beamforming and thus increasing the system data transmission rate. Attached Figure Description

[0045] Figure 1 Reconfigurable refractive metasurface antenna.

[0046] Figure 2 Signal transmitting and receiving devices based on reconfigurable refractive metasurfaces.

[0047] Figure 3 The method flowchart of the present invention.

[0048] Figure 4 A comparison chart of simulation results between the present invention and existing technologies. Detailed Implementation

[0049] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only specific embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0050] A reconfigurable refractive metasurface antenna consists of a feed source and a refractive metasurface. For example... Figure 1 As shown, the refractive metasurface is an array of multiple subwavelength elements. Each element has a PIN diode, which can be switched between ON and OFF by adjusting the bias voltage across it. When a signal is incident on each element, it undergoes refraction. By adjusting the state of the diodes on the elements, the phase of the refracted wave can be changed. The beamforming process of this reconfigurable refractive metasurface antenna is as follows: the signal emitted by the feed is refracted when it is incident on each element. During this refraction process, the metasurface elements apply a certain phase shift to the signal. By adjusting the bias voltage on the diodes, the refraction phase shift of the elements can be appropriately set, thereby achieving beamforming.

[0051] Please refer to Figure 2 and Figure 3 , Figure 2 This is a signal transmitting and receiving device based on a reconfigurable refractive metasurface. Figure 3 This is a flowchart of the method of the present invention. Figure 2 As shown, the signal transmitting device of the present invention consists of five modules: 1) a signal transmitting module, used to send a first pilot sequence and data signal to a user; 2) a signal receiving module, used to receive the user's feedback on the first pilot sequence and the data signal sent by the user; and 3) a channel estimation module, used to estimate the channel h between the feed source and the reconfigurable refractive metasurface based on the received user feedback on the first pilot sequence. F,(m,n) The channel h between the reconfigurable refractive metasurface and the user (m,n),U 1) Where m is the row number of the element and n is the column number of the element; 4) An incident angle and exit angle estimation module, used to estimate the incident angle θ′ of the feed source to each element of the reconfigurable refractive metasurface based on the received user feedback on the first pilot sequence. (m,n)The exit angle θ from each unit of the reconfigurable refractive metasurface to the user (m,n) , where m is the row number of the element and n is the column number of the element; 5) Reconfigurable refractive metasurface state design module, used to design the state of the reconfigurable refractive metasurface based on the channel h. F,(m,n) and h (m,n),U , emission angle θ (m,n) and the angle of incidence θ′ (m,n) The state of each unit of the reconfigurable refractive metasurface during the data transmission and reception phases is designed.

[0052] Taking a narrowband downlink network as an example, this network includes one user and one base station. The base station has the same architecture as the signal transmission and reception device we proposed. Assume the refractive metasurface contains M*N units, each unit having a size of s. M ×s N Let A denote the refraction amplitude and phase shift of the (m,n)th element. m,n and The transmission coefficient of this unit can then be written as: First, we model the transmission channel and the data transmission rate during the transmission phase. Assume the transmission channel consists of M×N metasurface-based channels, where the (m,n)th channel represents the channel from the feed source through the (m,n)th metasurface unit to the user. The channel gain of the (m,n)th metasurface-based channel can be expressed as...

[0053]

[0054] Among them, h F,(m,n) h represents the channel between the feed source and the (m,n)th metasurface unit. (m,n),U This represents the channel between the (m,n)th metasurface unit and the user. This represents the transmission coefficient of the (m,n)th metasurface unit during the transmission phase, which varies with the state of the unit during the data transmission phase. It varies with the change, and is affected by the incident angle θ′ from the feed source to the element. (m,n) and the emission angle θ from the unit to the user. (m,n) The impact of this. In summary, the channel from the feed to the user can be written as...

[0055]

[0056] The user's received signal-to-noise ratio can be expressed as...

[0057]

[0058] Where P Tx and (σ) Tx ) 2These represent the transmit power of the feedhorn and the variance of the additive white Gaussian noise received by the user, respectively. Therefore, the data transmission rate from the base station to the user can be written as:

[0059] R Tx =log2(1+γ) Tx )

[0060] Based on the expression for the data transmission rate during the sending phase, a data sending rate maximization problem is constructed.

[0061]

[0062]

[0063] The first constraint indicates that the state of each metasurface element can only take values ​​from S. By solving this problem, the optimal state of each element of the refractive metasurface during the transmission phase can be obtained, and the state of each metasurface element can be set to this optimal value during the transmission phase.

[0064] We model the receive channel and the data transmission rate during the receive phase using a similar approach. The receive channel consists of M×N metasurface-based channels, where the (m,n)th channel represents the channel from the user through the (m,n)th metasurface unit to the feed. The channel gain of the (m,n)th metasurface-based channel can be expressed as:

[0065]

[0066] in This represents the transmission coefficient of the (m,n)th metasurface unit during the receiving phase, which varies with the state of the unit during the receiving phase. It varies with the change, and is affected by the incident angle θ′ from the feed source to the element. (m,n) and the emission angle θ from the unit to the user. (m,n) The impact of this. In summary, the channel from the feed to the user can be written as...

[0067]

[0068] The user's received signal-to-noise ratio can be expressed as...

[0069]

[0070] Where P Rx and (σ) Rx ) 2 These represent the user's transmit power and the variance of the additive white Gaussian noise received by the transceiver, respectively. Therefore, the rate at which the user sends data to the transceiver can be written as:

[0071] RRx =log2(1+γ) Rx )

[0072] Based on the expression for the data transmission rate during the reception phase, a data reception rate maximization problem is constructed.

[0073]

[0074]

[0075] By solving this problem, the optimal state of each unit of the refractive metasurface during the receiving stage can be obtained, and the state of each metasurface unit can be set to this optimal value during the receiving stage.

[0076] The simulation environment for this invention and the traditional transceiver architecture is as follows: the base station transmit power is set to 43dBm, the variance of additive white Gaussian noise is set to -96dBm, the system operating frequency is set to 26GHz, there is only one user, the distance between the user and the metasurface array is 200m, and each user uses an omnidirectional antenna to receive signals. For the reconfigurable refractive metasurface antenna, its feed is an omnidirectional antenna, and the distance between it and the metasurface array is 0.1m. Assume the element transmittance is 1, and the element size is... Where λ is the wavelength corresponding to the system's operating frequency. We assume that the existing transceiver architecture using metamaterial antennas does not include incident and exit angle estimation modules. For the existing transceiver architecture using metamaterial antennas, we assume that its channel estimation module can accurately estimate the channel. For our proposed transceiver architecture, we assume that both the channel estimation module and the incident / exit angle modules can accurately perform estimations. Figure 4 As shown, with the same number of RRS units, the proposed transceiver architecture can achieve a higher average transmit / receive rate than the traditional transceiver architecture.

[0077] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A signal transmission and reception method based on a reconfigurable refractive metasurface antenna, applied to a signal transmission and reception device based on a reconfigurable refractive metasurface antenna, wherein the reconfigurable refractive metasurface antenna comprises: The method includes a feed source and a reconfigurable refractive metasurface, comprising: The first pilot sequence is sent to the user, who then provides feedback on the received signals. The system receives feedback from the user on the first pilot sequence and, based on the feedback, estimates the channel between the feed and the reconfigurable refractive metasurface. The channel between the reconfigurable refractive metasurface and the user The incident angle of the feed source to each unit of the reconfigurable refractive metasurface The exit angle from each unit of the reconfigurable refractive metasurface to the user , where m is the row number of the cell and n is the column number of the cell; According to the channel and , angle of departure Angle of incidence The state of each unit of the reconfigurable refractive metasurface during the data transmission and reception phases is designed. Data is transmitted and received based on the state of the designed reconfigurable refractive metasurface. The design of the reconfigurable refractive metasurface includes the following: modeling the relationship between the state of each unit and the data transmission rate. The modeling of the relationship between the state of each unit and the data transmission rate includes: Based on the state of the cell during the data transmission phase, the incident angle from the feed to the cell, the exit angle from the cell to the user, the channel between the feed and the cell, and the channel between the cell and the user, calculate the gain of the (m,n)th metasurface-based channel. Calculate the channel between the feed and the user based on the channel gain. ; Based on the channel The user's received signal-to-noise ratio is obtained by taking the variance of the feed's transmit power and the additive white Gaussian noise received by the user. Based on the received signal-to-noise ratio, model the relationship between the state of each unit and the data transmission rate; The channel gain of the (m,n)th metasurface-based channel can be represented by the following parameters: the channel between the feed and the (m,n)th metasurface unit, the channel between the (m,n)th metasurface unit and the user, and the transmission coefficient of the (m,n)th metasurface unit during the transmission phase.

2. The method as described in claim 1, characterized in that, Sending the first pilot sequence to the user includes: The baseband unit processes the first pilot sequence; The digital-to-analog converter unit converts the processed signal into an analog signal. The analog signal is converted into a radio frequency signal via a transmission radio frequency link; The radio frequency signal is transmitted using the reconfigurable refractive metasurface antenna.

3. The method as described in claim 1, characterized in that, Receiving feedback from the user on the first pilot sequence includes: The user's feedback on the first pilot sequence is received using the reconfigurable refractive metasurface antenna. Use a receiving radio frequency link to convert the received signal into an analog signal; The analog signal is converted into a digital signal by an analog-to-digital converter. The digital signal is processed by the baseband unit.

4. The method as described in claim 1, characterized in that, The design of the reconfigurable refractive metasurface also includes the states of each unit during the data transmission phase: Adjust the state of each unit to maximize the data transmission rate.

5. The method as described in claim 1, characterized in that, The states of each unit cell of the reconfigurable refractive metasurface in the data reception phase of the design include: Model the relationship between the state of each unit and the rate of data reception; Adjust the status of each unit to maximize the data reception rate.

6. The method as described in claim 5, characterized in that, The modeling of the relationship between the state of each unit and the rate of data reception includes: Based on the state of the cell during the data reception phase, the incident angle from the feed to the cell, the exit angle from the cell to the user, the channel between the feed and the cell, and the channel between the cell and the user, calculate the gain of the (m,n)th metasurface-based channel. Calculate the channel between the feed and the user based on the channel gain. ; Based on the channel The user's transmit power and the variance of the additive white Gaussian noise received by the transceiver are used to obtain the received signal-to-noise ratio of the transceiver. Based on the received signal-to-noise ratio, the relationship between the state of each unit and the received data rate is modeled.

7. A signal transmitting and receiving device based on a reconfigurable refractive metasurface antenna, wherein the reconfigurable refractive metasurface antenna comprises: The signal transmitting and receiving device includes a feed source and a reconfigurable refractive metasurface. The signal transmission module is used to send the first pilot sequence and data signals to the user; The signal receiving module is used to receive user feedback on the first pilot sequence and data signals sent by the user. A channel estimation module is used to estimate the channel between the feed source and the reconfigurable refractive metasurface based on the received user feedback on the first pilot sequence. The channel between the reconfigurable refractive metasurface and the user Where m is the row number of the cell and n is the column number of the cell; An incident angle and exit angle estimation module is used to estimate the incident angle from the feed source to each unit of the reconfigurable refractive metasurface based on the received user feedback on the first pilot sequence. The exit angle from each unit of the reconfigurable refractive metasurface to the user , where m is the row number of the cell and n is the column number of the cell; The reconfigurable refractive metasurface state design module is used to design states based on the channel. and , angle of departure Angle of incidence The state of each unit of the reconfigurable refractive metasurface during the data transmission and reception phases is designed. The reconfigurable refractive metasurface state design module is further used to execute the design of the state of each unit of the reconfigurable refractive metasurface during the data transmission and reception phase in the following manner: modeling the relationship between the state of each unit and the rate of data transmission; The modeling of the relationship between the state of each unit and the data transmission rate includes: Based on the state of the cell during the data transmission phase, the incident angle from the feed to the cell, the exit angle from the cell to the user, the channel between the feed and the cell, and the channel between the cell and the user, calculate the gain of the (m,n)th metasurface-based channel. Calculate the channel between the feed and the user based on the channel gain. ; Based on the channel The user's received signal-to-noise ratio is obtained by taking the variance of the feed's transmit power and the additive white Gaussian noise received by the user. Based on the received signal-to-noise ratio, model the relationship between the state of each unit and the data transmission rate; The channel gain of the (m,n)th metasurface-based channel can be represented by the following parameters: the channel between the feed and the (m,n)th metasurface unit, the channel between the (m,n)th metasurface unit and the user, and the transmission coefficient of the (m,n)th metasurface unit during the transmission phase.

8. A storage medium storing a computer program, wherein, The computer program is configured to execute the method of any one of claims 1-6 at runtime.

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