Intelligent reflecting surface hybrid array arrangement design method

Abstract

The invention discloses a hybrid array arrangement design method for an intelligent reflecting surface, belongs to the technical field of wireless communication, and solves the technical problem of poor performance of an existing hybrid intelligent reflecting surface. The method comprises the following steps: step 1, determining an index 1: enabling a reflection phase of an active unit to be close to a reflection phase of one state of a passive unit; step 2, determining an index 2, wherein the index 2 is that an active unit is placed at a corresponding position according to a codebook so as to maintain a relatively high beam forming capability in a low power consumption state; 3, orderly arranging the active units and the passive units in advance according to the index I and the index II; and 4, carrying out analog simulation on the arranged active units and passive units, and adjusting the number of the active units and the number of the passive units according to a simulation result, so that the arranged active units and the arranged passive units meet the index I and the index II. And the beam forming capability of the array in a low-power-consumption mode is effectively improved, and meanwhile, the signal gain during active work is not influenced.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of wireless communication, more particularly, it relates to a smart reflecting surface hybrid array arrangement design method. BACKGROUND

[0002] Reconfigurable intelligent surfaces (RIS) have been proposed and widely developed in the past few years. This is because RIS can intelligently configure the propagation environment. RIS is also considered as a promising technology for future sixth generation (6G) communication networks. Specifically, RIS is composed of many independent elements, which can scatter incident electromagnetic waves and impose a specified phase. By intelligently configuring the state or scattering phase of each element on the RIS, various scattering characteristics can be achieved, such as beamforming or interference nulling. Therefore, RIS can enhance the received signal-to-interference-and-noise ratio (SINR) or provide physical layer security. In addition, due to the simple structure of RIS, compared with traditional RF chain communication systems, RIS has broad prospects in future energy and spectrum efficient wireless communication.

[0003] However, passive smart reflecting surfaces do not have electromagnetic wave amplification capability, and the signal is easily affected by "double fading" (i.e. the superposition fading of direct link and reflected link) during the reflection transmission process. At this time, a hybrid smart reflecting surface is used, which can enhance the signal strength of the reflected wave to a certain extent by adding active units to the passive RIS. However, in the hybrid smart reflecting surface, sometimes the amplification function is not used, and the active unit does not have a phase shift function, which will cause the overall beamforming performance to be worse than that of a pure passive RIS. SUMMARY

[0004] The technical problem to be solved by the present application is to overcome the above-mentioned deficiencies of the prior art. The purpose of the present application is to provide a smart reflecting surface hybrid array arrangement design method to meet the actual needs in different scenarios and effectively improve the beamforming capability in the low power consumption mode of the array while not affecting the signal gain in the active working state.

[0005] The technical solution of the present application is: a smart reflecting surface hybrid array arrangement design method, comprising the following steps: Step 1. Determine index one, which is to make the reflection phase of the active unit close to the reflection phase of one of the states of the passive unit; Step 2. Determine index two, which is to place the active unit in the corresponding position according to the codebook to maintain high beamforming capability in the low power consumption state; Step 3. Pre-arrange the active unit and the passive unit according to the index one and the index two; Step 4. Simulate the arranged active units and passive units, and adjust the number of active units and passive units according to the simulation results, so that the arranged active units and passive units meet the index one and index two.

[0006] As a further improvement, the active units and passive units are arranged in column or row units.

[0007] Further, the passive units are located on the two most edge sides.

[0008] Further, the active units and passive units are split into small arrays in column or row units.

[0009] Further, the arrangement structure of the active units and passive units is: arranging 3 columns of passive unit arrays, 2 columns of active unit arrays, 2 columns of passive unit arrays, 2 columns of active unit arrays, and 3 columns of passive unit arrays in sequence.

[0010] Further, 1 column of passive unit array includes 9 passive units, and 1 column of active unit array includes 6 active units.

[0011] Advantages Compared with the prior art, the present application has the advantages of: 1. The present application can freely control the number and proportion of active units and passive units to meet the actual needs in different scenarios.

[0012] 2. The present application can effectively improve the beamforming capability of the array in low power consumption mode while not affecting the signal gain in active operation. BRIEF DESCRIPTION OF DRAWINGS

[0013] Fig. 1 is a mixed type intelligent reflecting surface array diagram; Fig. 2 is a simulation result diagram of the reflection signal intensity of the mixed type intelligent reflecting surface in different arrangement modes under low power consumption state; Fig. 3 is a simulation result diagram of the reflection signal intensity of the mixed type intelligent reflecting surface in different arrangement modes under amplification state; Wherein: 1-active unit, 2-passive unit. DETAILED DESCRIPTION

[0014] The present application will be further described below in conjunction with specific embodiments in the drawings.

[0015] Reference Figs. 1-3 A mixed type intelligent reflecting surface array arrangement design method, comprising the following steps: Step 1. Determine index one, index one is: make the reflection phase of the active unit close to the reflection phase of one state of the passive unit; Step 2. Determine index two, index two is: according to the codebook, place the active unit in the corresponding position to maintain high beam forming ability in low power consumption state; Step 3. Pre-arrange the active unit and the passive unit according to index one and index two; Step 4. Simulate the arranged active unit and passive unit, and adjust the number of active units and passive units according to the simulation results, so that the arranged active unit and passive unit meet index one and index two.

[0016] Specifically, as shown in Fig. 1 , the active unit and the passive unit are arranged in columns or rows. Among them, the passive unit is located on the two sides of the edge.

[0017] Preferably, the active unit and the passive unit are disassembled into small arrays in column or row units. That is, unlike the traditional smart reflective surface array, the active unit and the passive unit of the present application are not placed on one array board, but are made into small arrays in column or row units, and each small array can be freely assembled, and the assembly is very flexible and convenient.

[0018] Preferably, the arrangement structure of the active unit and the passive unit is: 3 columns of passive unit arrays, 2 columns of active unit arrays, 2 columns of passive unit arrays, 2 columns of active unit arrays, and 3 columns of passive unit arrays. (Such structure is suitable for the scene of incident wave 0° and outgoing wave 30°, and the rest of the scene needs to be changed according to the specific codebook.) Specifically, 1 column of passive unit array includes 9 passive units, and 1 column of active unit array includes 6 active units. In actual application, multiple small arrays can be combined and fixed through the antenna cover of the array.

[0019] In low power consumption state, since the phase shifter and the amplification circuit in the active unit do not work, the active part cannot change the reflection phase of the incident wave. The conventional method is prone to poor beam forming ability in low power consumption state when the proportion of active units is greater than 30%, which makes the advantages of hybrid smart reflective surface not obvious compared with active reflective surface. As shown in Fig. 2 , the frequency of the input signal is 2.4 GHz, the phase is 90°, the blue color is the signal strength of using the present application, the red color is the signal strength of not using the present application, and the codebook of incident 0° and outgoing 30° is used. When the proportion of array active units is 25%, the signal strength is shown in red, and it can be seen that the highest signal strength has deviated from 30°, and the beam forming ability is poor. In the present application, by making the reflection phase of the active unit close to the reflection phase of the passive unit in the diode off state, when the array is composed,Fig. 1 As shown, the active unit is placed in the codebook in the off state of the passive unit to replace its function, such as... Fig. 2 As shown, the signal strength is improved by 5dB, and the beamforming capability is high. (As indicated...) Fig. 3 As shown, the input signal frequency is 2.4 GHz and the phase is 90°. Red represents the signal strength using this design, and purple represents the signal strength without this design. In amplification mode, the gain is almost unaffected. In practical applications, the positions of active and passive units in the hybrid array can be adjusted according to commonly used codebooks to achieve the advantages of this invention.

[0020] The above are merely preferred embodiments of the present invention. It should be noted that those skilled in the art can make several modifications and improvements without departing from the structure of the present invention, and these will not affect the effectiveness of the implementation of the present invention or the practicality of the patent.

Claims

1. A method for designing a hybrid array arrangement of intelligent reflective surfaces, characterized in that, Includes the following steps: Step 1. Determine index one, which is: make the reflection phase of the active unit close to the reflection phase of one of the states of the passive unit; Step 2. Determine indicator two, which is: placing active units in appropriate positions according to the codebook to maintain a high beamforming capability under low power consumption conditions; Step 3. Arrange the active and passive units in an orderly manner according to the first and second indicators; Step 4. Simulate the arranged active and passive units, and adjust the number of active and passive units according to the simulation results so that the arranged active and passive units meet the stated index one and index two.

2. The intelligent reflective surface hybrid array arrangement design method according to claim 1, characterized in that, The active and passive units are arranged alternately in columns or rows.

3. The intelligent reflective surface hybrid array arrangement design method according to claim 2, characterized in that, The passive units are located on the two outermost sides.

4. The intelligent reflective surface hybrid array arrangement design method according to claim 2, characterized in that, The active and passive units are divided into small arrays in columns or rows.

5. The intelligent reflective surface hybrid array arrangement design method according to claim 4, characterized in that, The arrangement of the active and passive units is as follows: 3 columns of passive unit array, 2 columns of active unit array, 2 columns of passive unit array, 2 columns of active unit array, and 3 columns of passive unit array are arranged in sequence.

6. The intelligent reflective surface hybrid array arrangement design method according to claim 5, characterized in that, A single-column passive cell array consists of 9 passive cells, and a single-column active cell array consists of 6 passive cells.

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