CN114024595A - Communication method and system for surface terminal - Google Patents
Communication method and system for surface terminal Download PDFInfo
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Abstract
The invention relates to a communication method and a system for an amphibious terminal, which have the core that a reconfigurable intelligent reflecting surface RIS is adopted to realize the two-way communication between a relay device (a mother ship) and a land terminal, fully utilize various advantages and performances of the reconfigurable intelligent reflecting surface RIS and improve the convenience and the precision of the amphibious communication. Furthermore, cable wired communication and RIS wireless communication (a power line carrier communication technology and a reconfigurable intelligent reflecting surface assisted radio frequency communication technology are combined) are combined to form a complete communication chain between the land and water terminals, the advantages of the land and water terminals are combined, the construction is simple, the cost is low, and the information interaction effect is good.
Description
Technical Field
The invention relates to the field of wireless communication, in particular to a wireless communication technology for an amphibious terminal.
Background
China has a vast ocean area and contains rich oil gas, mineral products and biological resources. As the pace at which humans understand and develop the ocean has increased, the need for land and water communications has become more stringent. For example, in the marine science investigation activity, the marine environment monitoring activity, the marine resource investigation and development activity, the fishery resource fishing activity and the like, a wireless, reliable and good-confidentiality two-way information transmission mode is urgently needed between an underwater terminal (S) (such as an underwater robot, an underwater sensor and the like) and a surface mother ship and between a land terminal (D) so as to transmit information such as characters, sound, images, control signals and the like.
At present, the mainstream land-water communication comprises A underwater acoustic communication and B underwater optical wireless communication. Wherein, A: the underwater acoustic channel is the most complex channel in the field of wireless communication, and is caused by scattering and refraction effects caused by wave fluctuation of the sea surface, uneven layering and unevenness of the sea bottom, and non-uniformity of seawater medium when the acoustic wave propagates in the sea. However, 1, its bandwidth resources are limited: in radio communication, the frequency range that can be used is 2 kHz-3000 GHz, the highest frequency of sound waves (ultrasonic waves) can also reach 5 GHz or higher, however, when applied to underwater acoustic communication, the available bandwidth is only in the order of tens of kHz, mainly because high frequency sound waves are severely attenuated when propagating in seawater; 2. the noise interference is serious: noise in the ocean such as tides, ocean currents, sea surface waves, seismic activity, biological populations, traffic and shipping will cause severe transmission loss; 3. the performance is poor: random inhomogeneity of seawater media (such as temperature, seasonal flow, tide), and random fluctuation of sound field in the ocean, and this random fluctuation effect also affects the performance of underwater acoustic communication. B: the underwater optical wireless communication is unstable, and the transmission performance and accuracy are seriously influenced.
The existing land and water communication scheme mainly adopts underwater acoustic communication and satellite communication, and is specific: the underwater terminal (S) transmits information to the mother ship through underwater acoustic communication and then transmits the information to the land terminal (D) through satellite communication. However, as mentioned above, underwater acoustic communication has a number of fatal drawbacks, in addition to high satellite communication cost and limited two-way communication capability. Therefore, how to achieve two-way communication between land and water terminals conveniently, quickly, accurately and at low cost is an important technical problem to be solved urgently at present, and is concerned with further understanding and more effective development of the ocean.
Disclosure of Invention
In order to solve the technical problem, the invention provides a communication method for an amphibious terminal, which comprises the following steps:
s1: the underwater terminal S sends a data signal to the relay device T;
s2: the relay device T receives the data signal and sends the data signal to the reconfigurable intelligent reflecting surface;
s3: the reconfigurable intelligent reflecting surface adjusts the amplitude and the phase of the data signal in a reflecting manner, and sends the data signal after the adjustment in the reflecting manner to a land terminal D;
or
S1': the land terminal D sends a data signal to the reconfigurable intelligent reflecting surface;
s2': the reconfigurable intelligent reflecting surface receives the data signal, adjusts the amplitude and the phase of the data signal in a reflecting manner, and sends the data signal after being adjusted in the reflecting manner to the relay device T;
s3': and the relay equipment T receives the data signal after reflection adjustment and sends the data signal to the underwater terminal S.
Further, in step S3, the reflection adjusting the amplitude and the phase of the data signal includes:
s31: adjusting the amplitude of the data signal to a maximum amplitude;
s32: adjusting the phase of the data signal, and directionally transmitting the data signal to the land terminal D;
in step S2', reflection-adjusting the amplitude and phase of the data signal, including:
s21': adjusting the amplitude of the data signal to a maximum amplitude;
s22': and adjusting the phase of the data signal, and directionally transmitting the data signal to the relay device T.
Further, the step S31 includes:
s31 a: according to the performance parameters of the reconfigurable intelligent reflecting surface RIS, determining a fading channel from the relay equipment T to the reconfigurable intelligent reflecting surface RIS as
；
S31 b: according to the performance parameters of the reconfigurable intelligent reflecting surface RIS, determining a fading channel between the reconfigurable intelligent reflecting surface RIS and the land terminal D as
；
S31 c: the reflection coefficient of each reflection unit of the reconfigurable intelligent reflecting surface RIS is controlled to meet the requirements
So that the signal received by said terrestrial terminal D reaches a maximum amplitude;
the step S31' includes:
s21' a: according to the performance parameters of the reconfigurable intelligent reflecting surface RIS, determining a fading channel from the land terminal D to the reconfigurable intelligent reflecting surface RIS as
；
S21' b: according to the performance parameters of the reconfigurable intelligent reflecting surface RIS, determining a fading channel from the reconfigurable intelligent reflecting surface RIS to the relay equipment T as
；
S21' c: the reflection coefficient of each reflection unit of the reconfigurable intelligent reflecting surface RIS is controlled to meet the requirements
The signal received by the relay device T is enabled to reach the maximum amplitude;
wherein,
、
are respectively provided withFor a channel
The amplitude and the phase of (a) of (b),
、
are channels respectively
The amplitude and the phase of (a) of (b),
the phase of the reflection coefficient of each reflection unit of the intelligent reflection surface can be reconstructed.
Further, the step S32 includes:
s32 a: sensing the position of the land terminal D;
s32 b: analyzing the expected on-off state of each reflecting unit of the reconfigurable intelligent reflecting surface RIS according to the position of the land terminal D so as to directionally send the data signal to the land terminal D;
s32 c: sending a control signal according to the expected on-off state to control the on-off of each reflecting unit of the reconfigurable intelligent reflecting surface RIS;
the step S22' includes:
s22' a: sensing the position of the relay device T;
s22' b: analyzing the expected on-off state of each reflecting unit of the reconfigurable intelligent reflecting surface RIS according to the position of the relay device T so as to directionally send the data signal to the relay device T;
s22' c: and sending a control signal according to the expected on-off state to control the on-off of each reflecting unit of the reconfigurable intelligent reflecting surface RIS.
In another aspect, the present invention also provides a communications system for an amphibious terminal comprising: the system comprises an underwater terminal S, a relay device T, a reconfigurable intelligent reflecting surface RIS and a land terminal D which are connected in sequence;
the communication system, configured to perform the communication method according to any one of claims 1 to 4.
Further, the communication system further includes: and the control device is connected with the reconfigurable intelligent reflecting surface RIS and is used for controlling the reconfigurable intelligent reflecting surface RIS and reflecting and adjusting the amplitude and the phase of the data signal.
Further, the control device X includes: a receiving unit X100, a sensing unit X200, an analyzing unit X300, and a control unit X400;
the receiving unit X100 is connected with the analysis unit X300, and is used for receiving the performance parameters of the reconfigurable intelligent reflecting surface RIS and sending the performance parameters to the analysis unit X300;
the sensing unit X200 is connected to the analysis unit X300, and configured to sense a real-time position of the land terminal D or the relay device T, and send the real-time position to the analysis unit X300;
the analysis unit X300 is connected with the control unit X400 and is used for determining the phase of the reflection coefficient of each reflection unit of the reconfigurable intelligent reflection surface according to the performance parameters of the reconfigurable intelligent reflection surface RIS and the real-time position of the land terminal D or the relay equipment T
And an expected on-off state, and sent to the control unit X400;
the control unit X400 is connected with the reconfigurable intelligent reflecting surface RIS and is used for controlling the operation according to the control unit X400
And sending a control signal according to the expected on-off state to control the reconfigurable intelligent reflecting surface RIS.
Further, the relay device T is arranged on a ship.
Further, the reconfigurable intelligent reflecting surface RIS is arranged on an aerial aircraft.
Further, the underwater terminal S is connected with the relay device T through a cable.
The invention provides a communication method and a system for an amphibious terminal, which adopts a reconfigurable intelligent reflecting surface RIS to realize the two-way communication between a relay device (mother ship) and a land terminal. Its advantages are self-evident: 1. the reconfigurable intelligent reflecting surface RIS has the advantages that the reconfigurable intelligent reflecting surface RIS can be designed according to actual requirements, is preferably arranged on aerial aircrafts (such as unmanned aerial vehicles, airplanes and the like), is convenient and fast to install and low in cost, can be installed in a wide sky, can comprehensively cover the ocean range, and is wide in application range; 2. the reconfigurable intelligent reflecting surface RIS is auxiliary equipment in a wireless communication network, and when the reconfigurable intelligent reflecting surface is deployed in the existing communication system, the standardization and the change of hardware are not needed, and only the communication protocol is needed to be matched; the method is not influenced by noise of a receiver, devices such as analog-digital/digital-analog conversion, a power amplifier and the like are not needed when signals are received, introduction and amplification of noise are reduced, full-duplex transmission can be provided, and theoretically, the method can work at any frequency; therefore, the application range is wide, and the applicability is strong; 3. the reconfigurable intelligent reflecting surface RIS is composed of passive elements/structures, each element only has a reflecting function (functions of amplitude modulation, phase shift and the like on input signals), power is hardly consumed, no energy is needed under ideal conditions, the requirements of energy conservation and consumption reduction are met, and the use cost is greatly reduced. The advantages of the method are given only as examples and are not limited thereto.
Drawings
Figures 1-2 are flow diagrams of one embodiment of a communication method for an amphibious terminal of the present invention;
figure 3 is a block diagram of one embodiment of a communication system for an amphibious terminal of the present invention;
figures 4-5 are flow diagrams of one embodiment of steps S3 and S2' of the method of communication for an amphibious terminal of the present invention;
figures 6-7 are flow diagrams of one embodiment of steps S31 and S21' of the method of communication for an amphibious terminal of the present invention;
figures 8-9 are flow diagrams of one embodiment of steps S32 and S22' of the method of communication for an amphibious terminal of the present invention;
FIG. 10 is a block diagram of one embodiment of the reconfigurable intelligent reflecting surface RIS of the present invention;
FIG. 11 is a voltage control diagram of one embodiment of the reconfigurable intelligent reflector RIS of the present invention;
FIGS. 12-14 are schematic phase diagrams of three embodiments of the reconfigurable intelligent reflective surface of the present invention;
figure 15 is a comparison of the effectiveness of the communication method of the present invention for surface terminals with other methods;
figure 16 is a block diagram of the structure of one embodiment of the communication system for the surface terminal of the present invention;
figure 17 is a block diagram of the structure of one embodiment of the control means of the communication system for surface terminals of the present invention.
Detailed Description
As shown in fig. 1 and 2, the present invention provides a communication method for an amphibious terminal, comprising:
s1: the underwater terminal S sends a data signal to the relay device T;
s2: the relay equipment T receives the data signal and sends the data signal to the reconfigurable intelligent reflecting surface RIS;
s3: reconstructing an intelligent reflecting surface RIS, adjusting the amplitude and the phase of a data signal in a reflection mode, and sending the data signal after the adjustment in the reflection mode to a land terminal D;
or
S1': the land terminal D sends a data signal to the reconfigurable intelligent reflecting surface RIS;
s2': the reconfigurable intelligent reflecting surface RIS receives the data signal, reflects and adjusts the amplitude and the phase of the data signal, and sends the data signal after reflection adjustment to the relay device T;
s3': and the relay equipment T receives the data signal after reflection adjustment and sends the data signal to the underwater terminal S.
In the embodiment, a specific implementation mode of the two-way communication of the amphibious terminal is given, and the core of the invention is to adopt a reconfigurable intelligent reflecting surface RIS to realize the two-way communication between the relay equipment (mother ship) and the land terminal. Specifically, the data signal of the two-way communication may be, but is not limited to, pictures, videos, texts, control signals, and the like. Preferably, the underwater terminal can be selected and not limited to feed back characters, sounds, images and the like to the land terminal (control center); the terrestrial terminals, optionally but not exclusively, send control signals to the underwater terminals. In this embodiment, it goes without saying that the advantages of the reconfigurable intelligent reflecting surface RIS are utilized: 1. the reconfigurable intelligent reflecting surface RIS has the advantages that the reconfigurable intelligent reflecting surface RIS can be designed according to actual requirements, is preferably arranged on aerial aircrafts (such as unmanned aerial vehicles, airplanes and the like), is convenient and fast to install and low in cost, can be installed in a wide sky, can comprehensively cover the ocean range, and is wide in application range; 2. the reconfigurable intelligent reflecting surface RIS is auxiliary equipment in a wireless communication network, and when the reconfigurable intelligent reflecting surface is deployed in the existing communication system, the standardization and the change of hardware are not needed, and only the communication protocol is needed to be matched; the method is not influenced by noise of a receiver, devices such as analog-digital/digital-analog conversion, a power amplifier and the like are not needed when signals are received, introduction and amplification of noise are reduced, full-duplex transmission can be provided, and theoretically, the method can work at any frequency; therefore, the application range is wide, and the applicability is strong; 3. the reconfigurable intelligent reflecting surface RIS is composed of passive elements/structures, each element only has a reflecting function (functions of amplitude modulation, phase shift and the like on input signals), power is hardly consumed, no energy is needed under ideal conditions, the requirements of energy conservation and consumption reduction are met, and the use cost is greatly reduced. The advantages of the method are given only as examples and are not limited thereto. Therefore, the implementation mode provides a convenient and quick communication mode with high accuracy and low cost for the two-way communication of the water and land terminal, and provides effective guarantee for further understanding and development of ocean resources.
Specifically, as shown in fig. 3, the effective communication between the underwater terminal S and the relay device T is optionally, but not limited to, an umbilical cable, and a power line carrier communication technology is utilized, so that on one hand, the erected power transmission line can be fully utilized, a new communication line is not required to be introduced, and the method is not only low in cost, but also can be fully applied to environments which are not beneficial to laying new lines, such as submarine pipelines, mines and the like; on the other hand, the wired communication mode is not influenced by underwater tide, noise, water temperature and the like, has strong stability, adopts the signal modulation and demodulation technology of the power carrier wave and the principle of orthogonal frequency division multiplexing, has quite mature technology, is widely applied to various electronic communication fields, and has high accuracy.
In the embodiment, a complete communication chain between the land and water terminals is formed by cable wired communication and RIS wireless communication (the combination of a power line carrier communication technology and a reconfigurable intelligent reflecting surface assisted radio frequency communication technology), the advantages of the land and water terminals are combined, the construction is simple, the cost is low, and the information interaction effect is good.
More specifically, as shown in fig. 3, taking the example that the underwater terminal S transmits a data signal to the land terminal D, in the first communication time slot (S-T): the underwater terminal S transmits signals to the relay equipment T on the mother ship through the umbilical cable, and the received signals are set as
Wherein
which represents the average transmission power, is,
representing data signals transmitted by the subsea terminal over the PLC link,
representing white gaussian noise; in the second communication time slot (T-RIS): the relay device T amplifies the received signals through a decoding forwarding protocol without executing any type of decoding, sets the amplification gain to G, and transmits the signals to a reconfigurable intelligent reflecting surface RIS on the unmanned aerial vehicle through a wireless radio frequency link; in the third communication gap (RIS-D): after the reconfigurable intelligent reflecting surface RIS adjusts the phase of the signal, the signal is directionally covered and finally transmitted to a land terminal D (control center receiver), and the received signal is
，
Which represents the average transmission power, is,
and
to be random variables subject to Rayleigh distribution, their mean and variance are respectively
And
，
represents the data signal transmitted by the relay device T,
representing gaussian white noise.
More specifically, as shown in step S3 in fig. 4, the reflection adjustment data signal includes, but is not limited to:
s31: adjusting the amplitude of the data signal to a maximum amplitude;
s32: adjusting the phase of the data signal, and directionally transmitting the data signal to the land terminal D;
as shown in fig. 5, in step S2', the reflection adjustment data signal optionally includes, but is not limited to:
s21': adjusting the amplitude of the data signal to a maximum amplitude;
s22': and adjusting the phase of the data signal and directionally transmitting the data signal to the relay device T.
In this embodiment, specific goals and requirements are given for adjusting the amplitude and phase of the data signal to its maximum amplitude that it can achieve to enhance its signal strength; the phase reaches a specific position to be communicated in order to direct coverage to the device (terrestrial terminal D or relay device T) that needs the signal. Finally, the signal transmission controllability is realized, and the accuracy and precision of the land-water communication are improved.
More preferably, as shown in fig. 6, step S31 optionally but not limited to includes:
s31 a: according to the performance parameters of the reconfigurable intelligent reflecting surface RIS, determining a fading channel from the relay equipment T to the reconfigurable intelligent reflecting surface RIS as
；
S31 b: according to the performance parameters of the reconfigurable intelligent reflecting surface RIS, determining a fading channel from the reconfigurable intelligent reflecting surface RIS to a land terminal D as
；
S31 c: in controlling the reflection coefficient of each reflection unit of the reconfigurable intelligent reflecting surface RIS, the requirements of
The signal received by the land terminal D reaches the maximum amplitude;
as shown in fig. 7, step S21' may optionally, but not exclusively, include:
s21' a: according to the performance parameters of the reconfigurable intelligent reflecting surface RIS, determining a fading channel from the land terminal D to the reconfigurable intelligent reflecting surface RIS as
；
S21' b: according to the performance parameters of the reconfigurable intelligent reflecting surface RIS, determining a fading channel from the reconfigurable intelligent reflecting surface RIS to the relay equipment T as
；
S21' c: in controlling the reflection coefficient of each reflection unit of the reconfigurable intelligent reflecting surface RIS, the requirements of
So that the signal received by the relay device T reaches the maximum amplitude;
wherein,
、
are channels respectively
The amplitude and the phase of (a) of (b),
、
are channels respectively
The amplitude and the phase of (a) of (b),
the phase of the reflection coefficient of each reflection unit of the intelligent reflection surface can be reconstructed.
In this embodiment, a specific embodiment for adjusting the amplitude of the data signal to the maximum amplitude is given, and a specific manner how the reconfigurable intelligent reflecting surface RIS adjusts the amplitude is described in detail. As shown in FIG. 3, taking the example of the underwater terminal S sending a data signal to the land terminal D, assume that the wireless channel between T-RIS and RIS-D is subject to Rayleigh fading
And
the fading channel between the T-RIS and the RIS-D is related to the number i of the reflecting units of the reconfigurable intelligent reflecting surface RIS,
and
are channels respectively
The amplitude and the phase of (a) of (b),
and
are channels respectively
The amplitude and the phase of (a) of (b),
and
to be random variables subject to Rayleigh distribution, their mean and variance are respectively
And
. Reconfigurable intelligent reflecting surface RIS can accurately obtain channel
And
phase of
、
Setting the reflection coefficient of the ith reconfigurable unit as
Thus, the instantaneous signal-to-noise ratio of the signal after reflection off the RIS can be selected but not limited to the label:
，
average signal-to-noise ratio determined for the field environment, for which purpose the average signal-to-noise ratio
Under certain conditions, the FPGA controller controls the reflection panel unit of the reconfigurable intelligent reflection surface RIS to ensure that
Then, the maximum instantaneous signal-to-noise ratio can be obtained, and the ideal maximum received signal, namely the maximum amplitude, can be obtained
Thereby realizing the active control of the electromagnetic wave.
More specifically, as shown in fig. 8, step S32 optionally but not limited to includes:
s32 a: sensing the position of the land terminal D;
s32 b: according to the position of the land terminal D, analyzing the expected on-off state of each reflecting unit of the reconfigurable intelligent reflecting surface RIS to directionally send the data signal to the land terminal D;
s32 c: sending a control signal according to an expected on-off state to control the on-off of each reflecting unit of the reconfigurable intelligent reflecting surface RIS;
as shown in fig. 9, step S22' may optionally, but not exclusively, include:
s22' a: sensing the position of the relay device T;
s22' b: according to the position of the relay device T, analyzing the expected on-off state of each reflecting unit of the reconfigurable intelligent reflecting surface RIS to directionally send the data signal to the relay device T;
s22' c: and sending a control signal according to the expected on-off state to control the on-off of each reflecting unit of the reconfigurable intelligent reflecting surface RIS.
In this embodiment, a specific embodiment of adjusting the phase of the data signal, directionally covering to the land terminal D or the relay device T is given, and a specific way how the reconfigurable intelligent reflecting surface RIS adjusts the phase is explained in detail. More specifically, steps S32b, S32 c; in S22 'b and S22' c, the controller can be selected but not limited to adopting microprocessors such as an FPGA (field programmable gate array) and a single chip microcomputer, and is responsible for timing update of the reconfigurable intelligent reflecting surface RIS and matching control of the on-off working state of the reconfigurable intelligent reflecting surface RIS. More specifically, taking fig. 10 as an example, the reconfigurable intelligent reflecting surface RIS optionally but not limited to include a three-layer architecture: 1. the outer layer medium substrate is printed and attached with a large number of metal sheet elements, the metal sheet elements directly interact with incident signals, and the reverse bias voltage of the diode on each unit is controlled by the FPGA as shown in figure 11, so that the on-off of the reflecting surface unit is realized, and the phase direction change of different reflecting states of signal beams can be realized under the condition of different on-off of the reflecting surface unit; 2. the middle layer isolation layer can be selected from but not limited to a copper plate, so that signal energy leakage is avoided; 3. the inner control layer can be selected but not limited to a control circuit board which is responsible for adjusting the reflection amplitude and the phase of each element, and is triggered by an intelligent controller such as an FPGA (field programmable gate array) and a single chip microcomputer which are attached to the reconfigurable intelligent reflecting surface RIS. More specifically, the triggering state thereof, i.e. the expected on-off state of each reflection unit of the reconfigurable intelligent reflecting surface RIS, is related to the phase thereof, and is optionally, but not limited to, illustrated by tables 1 to 4 and fig. 12 to 14.
Table 1 reconfigurable intelligent reflecting surface RIS panel initial state table 1/0 states
When the 8 × 8 panel unit states are all 1, as shown in table 2, after the data signal is transmitted to the reconfigurable intelligent reflecting surface RIS, the data signal is reflected by the reconfigurable intelligent reflecting surface RIS and then only has a beam signal in one direction, as shown in fig. 12.
Table 2 reconfigurable intelligent reflecting surface RIS panel state 1 table (all 1 state)
| 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 |
| 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 |
| 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 |
| 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 |
| 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 |
| 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 |
| 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 |
| 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 |
When the panel unit state of 8 × 8 is 0, 1 interval, as shown in table 3, after the data signal is propagated to the reconfigurable intelligent reflecting surface RIS, there are beam signals in two directions after being reflected by the reconfigurable intelligent reflecting surface RIS, as shown in fig. 13.
Table 3 reconfigurable intelligent reflecting surface RIS panel state 2 table (0/1 interval state)
| 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 |
| 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
| 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 |
| 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
| 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 |
| 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
| 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 |
| 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
When the panel unit state of 8 × 8 is 0, 1, 0, 1 checkerboard, as shown in table 4, after the data signal is propagated to the reconfigurable intelligent reflecting surface RIS, there are beam signals in four directions after being reflected by the reconfigurable intelligent reflecting surface RIS, as shown in fig. 14.
Table 4 reconfigurable intelligent reflecting surface RIS panel state 3 table (0/1 chessboard state)
| 1 | 0 | 1 | 0 | 1 | 0 | 1 | 0 |
| 0 | 1 | 0 | 1 | 0 | 1 | 0 | 1 |
| 1 | 0 | 1 | 0 | 1 | 0 | 1 | 0 |
| 0 | 1 | 0 | 1 | 0 | 1 | 0 | 1 |
| 1 | 0 | 1 | 0 | 1 | 0 | 1 | 0 |
| 0 | 1 | 0 | 1 | 0 | 1 | 0 | 1 |
| 1 | 0 | 1 | 0 | 1 | 0 | 1 | 0 |
| 0 | 1 | 0 | 1 | 0 | 1 | 0 | 1 |
To illustrate the effectiveness of the communication method of the present invention in detail, referring to fig. 15, the interruption probability of the communication system with reconfigurable intelligent reflector RIS assistance is lower than that of the communication system without RIS assistance, and the effect is more obvious as the signal-to-noise ratio increases. Meanwhile, the larger the number N of the reflection units of the reconfigurable intelligent reflection surface RIS is, the larger the number of the reflection surfaces is, the smaller the interruption probability of the system is, and the better the overall performance of the system is.
In another aspect, the present invention provides a communication system for executing the above communication method on the basis of the above communication method, as shown in fig. 3, including: the system comprises an underwater terminal S, a relay device T, a reconfigurable intelligent reflecting surface RIS and a land terminal D which are connected in sequence. Specifically, the underwater terminal S may be, but not limited to, an underwater independent device such as an underwater robot or an underwater sensor, or a device carried by a diver or a submarine. The relay device, optionally but not limited to being disposed on the ship, communicates bi-directionally with the mother ship, communicating information data or control data. The reconfigurable intelligent reflecting surface RIS can be selected and not limited to be arranged on an aerial vehicle, and is preferably an unmanned aerial vehicle or an airplane and the like; the specific structure can be selected from, but not limited to, artificial electromagnetic metamaterials, which are composed of specially designed periodic arrangements of sub-wavelength structural elements and have unique electromagnetic properties that do not exist in nature, such as negative refraction, complete absorption, and abnormal reflection/scattering. The geometrical shapes, such as square or open rings, the sizes, the directions, the arrangements and the like, can be set arbitrarily by those skilled in the art according to actual needs, so as to modify the response reflection amplitude and the phase of the single unit signals correspondingly. The land terminal D, which is optional but not limited to a terminal device in a control room, receives and views data, analyzes and processes the data, and transmits control data through a man-machine operation section. More specifically, the underwater terminal S and the relay device T are optionally but not limited to be in communication connection by using a PLC link of an umbilical cable; the relay equipment T and the reconfigurable intelligent reflecting surface RIS and the land terminal D are in communication connection by adopting a radio frequency RF link.
It should be noted that, the communication system of the present invention corresponds to any of the above-mentioned communication methods, and the combination of the technical features and the technical effects are not limited to the examples, and are not repeated herein. Specifically, parameters such as specific structures, sizes, distribution and number of reflection units, unit intervals and the like of the underwater terminal S, the relay device T, the reconfigurable intelligent reflecting surface RIS and the land terminal D can be customized by a person skilled in the art according to actual needs.
More specifically, the reflection adjustment process of the reconfigurable intelligent reflecting surface can be manually adjusted in advance by a person skilled in the art according to the requirements of the amplitude and the phase, and then the reflection process is performed, or the reflection adjustment process is automatically adjusted through controllers such as an FPGA (field programmable gate array), a singlechip and the like. Preferably, the performance parameters, the reflection coefficient, the on-off state and the like of the reconfigurable intelligent reflecting surface can be updated and matched in real time according to the current position of the land terminal D or the relay equipment T sensed in real time.
Preferably, as shown in fig. 16, the communication system further includes: and the control device X is connected with the reconfigurable intelligent reflecting surface RIS and is used for controlling the reconfigurable intelligent reflecting surface RIS and adjusting the amplitude and the phase of the 5G electromagnetic wave signals in a reflection mode.
More preferably, as shown in fig. 17, the control device X includes: a receiving unit X100, a sensing unit X200, an analyzing unit X300, and a control unit X400. The receiving unit X100 is connected with the analysis unit X300, and is used for receiving the performance parameters of the reconfigurable intelligent reflecting surface RIS and sending the performance parameters to the analysis unit X300; the sensing unit X200 is connected with the analysis unit X300, is used for sensing the position of the land terminal D or the relay equipment T, and sends the position to the analysis unit X300; an analysis unit X300 connected with the control unit X400 for analyzing
The expected on-off state of the intelligent reflecting surface RIS can be reconstructed and sent to the control unit X400; a control unit X400 connected with the reconfigurable intelligent reflecting surface RIS and used for controlling the operation of the system according to
And the expected on-off state sends out a control signal to control the reconfigurable intelligent reflecting surface RIS.
In the embodiment, a specific embodiment of the control device X is provided, the amplitude and the phase of the reflected data signal can be determined according to the performance parameters of the reconfigurable intelligent reflecting surface and the real-time position of the device which needs to directionally send the data signal, the automation degree is higher, and the matching performance is stronger.
The above communication system is created based on the above communication method, and combinations of technical features, technical functions, and advantageous effects of the above communication system are not described herein again, and each technical feature of the above embodiments may be arbitrarily combined, and for brevity of description, all possible combinations of each technical feature in the above embodiments are not described, however, as long as there is no contradiction between combinations of the technical features, the combinations of the technical features should be considered as the scope described in this specification.
The above-mentioned embodiments only express several embodiments of the present invention, and the description thereof is more specific and detailed, but not construed as limiting the scope of the invention. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the inventive concept, which falls within the scope of the present invention. Therefore, the protection scope of the present patent shall be subject to the appended claims.
Claims (10)
1. A method of communication for an amphibious terminal, comprising:
s1: the underwater terminal (S) sends a data signal to the relay device (T);
s2: the relay equipment (T) receives the data signal and sends the data signal to the reconfigurable intelligent reflecting surface;
s3: the reconfigurable intelligent reflecting surface is used for adjusting the amplitude and the phase of the data signal in a reflecting manner and sending the data signal after being adjusted in the reflecting manner to a land terminal (D);
or
S1': the land terminal (D) sends a data signal to the reconfigurable intelligent reflecting surface;
s2': the reconfigurable intelligent reflecting surface receives the data signal, adjusts the amplitude and the phase of the data signal in a reflecting manner, and sends the data signal after being adjusted in the reflecting manner to the relay equipment (T);
s3': and the relay equipment (T) receives the data signal after the reflection adjustment and sends the data signal to the underwater terminal (S).
2. The communication method according to claim 1,
in step S3, the reflection adjusting the amplitude and phase of the data signal includes:
s31: adjusting the amplitude of the data signal to a maximum amplitude;
s32: -adjusting the phase of said data signal, directed to said terrestrial terminals (D);
in step S2', reflection-adjusting the amplitude and phase of the data signal, including:
s21': adjusting the amplitude of the data signal to a maximum amplitude;
s22': -adjusting the phase of the data signal for directional transmission to the relay device (T).
3. The communication method according to claim 2,
the step S31 includes:
s31 a: according to the performance parameters of the reconfigurable intelligent reflecting surface (RIS), determining the fading channel between the relay equipment (T) and the reconfigurable intelligent reflecting surface (RIS) as
；
S31 b: according to the performance parameters of the reconfigurable intelligent reflecting surface (RIS), determining the fading channel between the reconfigurable intelligent reflecting surface (RIS) and the land terminal (D) as
；
S31 c: controlling a reflection coefficient of each reflection unit of the reconfigurable intelligent reflection surface (RIS) to satisfy
-causing the signal received by said terrestrial terminal (D) to reach a maximum amplitude;
the step S31' includes:
s21' a: determining a fading channel between the land terminal (D) and the reconfigurable intelligent reflecting surface (RIS) as
；
S21' b: according to the performance parameters of the reconfigurable intelligent reflecting surface (RIS), determining the fading channel between the reconfigurable intelligent reflecting surface (RIS) and the relay device (T) as
；
S21' c: controlling a reflection coefficient of each reflection unit of the reconfigurable intelligent reflection surface (RIS) to satisfy
-causing the signal received by said relay device (T) to reach a maximum amplitude;
wherein,
、
are channels respectively
The amplitude and the phase of (a) of (b),
、
are channels respectively
The amplitude and the phase of (a) of (b),
the phase of the reflection coefficient of each reflection unit of the intelligent reflection surface can be reconstructed.
4. The communication method according to claim 2,
the step S32 includes:
s32 a: -sensing the location of the terrestrial terminal (D);
s32 b: analyzing the expected on-off state of each reflecting unit of the reconfigurable intelligent reflecting surface (RIS) according to the position of the land terminal (D) so as to directionally transmit the data signal to the land terminal (D);
s32 c: sending a control signal according to the expected on-off state to control the on-off of each reflecting unit of the reconfigurable intelligent reflecting surface (RIS);
the step S22' includes:
s22' a: -sensing the position of the relay device (T);
s22' b: analyzing the expected on-off state of each reflecting unit of the reconfigurable intelligent reflecting surface (RIS) according to the position of the relay device (T) so as to directionally transmit the data signal to the relay device (T);
s22' c: and sending a control signal according to the expected on-off state to control the on-off of each reflecting unit of the reconfigurable intelligent reflecting surface (RIS).
5. A communication system for an amphibious terminal, comprising: the system comprises an underwater terminal (S), a relay device (T), a reconfigurable intelligent reflecting surface (RIS) and a land terminal (D) which are connected in sequence;
the communication system, configured to perform the communication method according to any one of claims 1 to 4.
6. The communication system of claim 5, further comprising: and the control device is connected with the reconfigurable intelligent reflecting surface RIS and is used for controlling the reconfigurable intelligent reflecting surface RIS and reflecting and adjusting the amplitude and the phase of the data signal.
7. The communication system according to claim 6, wherein the control device X comprises: a receiving unit X100, a sensing unit X200, an analyzing unit X300, and a control unit X400;
the receiving unit X100 is connected with the analysis unit X300, and is used for receiving the performance parameters of the reconfigurable intelligent reflecting surface RIS and sending the performance parameters to the analysis unit X300;
the sensing unit X200 is connected to the analysis unit X300, and configured to sense a real-time position of the land terminal D or the relay device T, and send the real-time position to the analysis unit X300;
the analysis unit X300 is connected with the control unit X400 and is used for determining the phase of the reflection coefficient of each reflection unit of the reconfigurable intelligent reflection surface according to the performance parameters of the reconfigurable intelligent reflection surface RIS and the real-time position of the land terminal D or the relay equipment T
And an expected on-off state, and sent to the control unit X400;
the control unit X400 is connected with the reconfigurable intelligent reflecting surface RIS and is used for controlling the operation according to the control unit X400
And sending a control signal according to the expected on-off state to control the reconfigurable intelligent reflecting surface RIS.
8. A communication system according to any of claims 5-7, characterized in that the relay device (T) is arranged on a ship.
9. The communication system according to any of claims 5 to 7, characterized in that the reconfigurable intelligent reflecting surface (RIS) is arranged on an airborne aircraft.
10. A communication system according to any of claims 5-7, characterized in that a cable connection is used between the underwater terminal (S) and the relay device (T).
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