An Overview of Wireless Communication Technology Using Deep Learning

with the development of 5G,the future wireless communication network tends to be more and more intelligent.In the face of new service de-mands of communication in the future such as super-heterogeneous network,multiple communication sce-narios,large number of antenna elements and large bandwidth,new theories and technologies of intelli-gent communication have been widely studied,among which Deep Learning(DL)is a powerful technology in artificial intelligence(AI).It can be trained to con-tinuously learn to update the optimal parameters.This paper reviews the latest research progress of DL in in-telligent communication,and emphatically introduces five scenarios including Cognitive Radio(CR),Edge Computing(EC),Channel Measurement(CM),End to end Encoder/Decoder(EED)and Visible Light Com-munication(VLC).The prospect and challenges of further research and development in the future are also discussed.

A Simulation Study on Channel Estimation for Cooperative Communication System in Sand-dust Storm Environment

There are many factors that influence the propagation of electromagnetic wave in the sand-dust storm environment, the scattering effect of dust particle is one of the major factors, so this paper focuses on the dust particles scattering function. The scattering of dust particles inevitably brings the multipath transmission of the signal, multipath propagation will bring the multipath fading of the signal. In this paper, we first investigate the use of AF and DF modes in a sand-dust storm environment. Secondly, we present a low-order modulation method should be used in cooperative communication system. Lastly, we evaluate the system performance for both of the moving nodes and power allocation. Experimental results validate the conclusion of theoretical derivation: the multipath fading is one of the main factors that affect the quality of signal transmission. Cooperative communication technology has good anti-fading ability, which can guarantee the signal transmission timely and correctly.

Ultra-Wideband Millimeter-Wave Vortex Beam Generation Based on Reflective Pancharatnam-Berry Phase Metasurface

Due to the gradual scarcity of spectrum resources,orbital angular momentum(OAM)technology has been proposed and developed continuously to broaden channel capacity.To solve this problem,some ultra-wideband reflective phase metasurface antennas working in millimeter band are designed to generate high purity vortex waves which carry OAM.Based on the Pancharatnam-Berry(PB)phase concept,the unit cell is composed of a metasurface,dielectric,metal grounding layer.Through the optimization design of the unit structure parameters,the reflected wave efficiency can be as high as 95%when covering 2元rotating phase,which realizes the basic requirements of PB phase concept and the relative bandwidth of 116%.Then the metasurface arrays are arranged according to vortex wave generation formula and phase compensation principle.In the 25 GHz to 35 GHz frequency wide band,integer(l=±1,±2,±3)decimal(l=±1.5)and high-mode(l=±8)OAM vortex beams are generated,respectively.The OAM purity analysis shows that the antennas can generate millimeter wave OAM beams with high purity in a wide band range,and with a maximum gain of up to 23.6 dBi.

A Novel Multi-Modal OAM Vortex Electromagnetic Wave Microstrip Array Antenna

In this paper,we combine the circular polarization technology and orbital angular momentum(OAM)into the array antenna design for the first time,achieve free switch of the different topological charges in the array by using high-speed radio frequency(RF)switch technology.We arrange microstrip patch antenna elements equidistantly along the circumference to form eight elements multi-modal OAM vortex electromagnetic wave microstrip array antenna.It can generate elec-tromagnetic waves with dual characteristics of circular polarization and multi-modal vortex OAM(where OAM mode values are l=0,l=±1,l=±2,l=±3).Through simulation,we find mutual coupling between the radiating elements is small relatively,and increasing the number of array elements can not only improve the beam quality,but also generate electromagnetic waves with a higher order of OAM modes.Antenna model can meet the basic demands of ordinary array antenna,and also confirm the practicality of this circular polarized microstrip antenna array model.

Modulation Recognition of Radio Signals Based on Edge Computing and Convolutional Neural Network

Software defined radio(SDR)is a wireless communication technology that uses modern software to control the traditional“pure hardware circuit”.It can provide an effective and secure solution to the problem of building multi-mode,multi-frequency and multifunction wireless communication equipment.Although the concept and application of SDR have been studied a lot,there is little discussion about the operating efficiency of the established system.For the purpose of shortening the delay of mapping and reducing the high computing load in the cloud,a radio monitoring system based on edge computing is developed to achieve the flexible,extensible and real-time monitoring of high-performance SDR applications.To promote the edge intelligence of deep learning(DL)service deployment through edge computing(EC),we developed an edge intelligence algorithm of convolutional neural network(CNN)based on attention mechanism to carry out modulation recognition(MR)of the edge signal and make MR closer to the antenna terminal.Through the experiment of the system and the edge algorithm,this thesis verifies the effectiveness of the developed multifunction radio signal monitoring system.

A Concentric Array for Generating Multimode OAM Waves

For the problem of multiplexing multimodal vortex electromagnetic waves,a double-ring concentric uniform circular array(CUCA)consisting of 12 circularly polarized antennas(4 inner rings and 8 outer rings)is proposed in this paper.A complex feeding network is solved by rotating the circularly polarized antennas at a certain angle.The antennas are rotationally symmetric and point to the center,generating orbital angular momentum(OAM)waves by feeding the same amplitude and phase signals.In addition,this paper combines millimeter wave(mm-wave)and ultra-wideband(UWB)with OAM.The proposed antenna array can generate OAM beams at 30∼40 GHz with l=−1,−2.When l=−1 the relative bandwidth is 25.2% and the gain is 8.03 dBi;when l=−2 the relative bandwidth is 27.7% and the gain is 9.43 dBi.The analysis of simulation results shows that the antenna array has UWB performance,good gain,and a standard spiral phase distribution,which can provide some practical significance for modal multiplexing of mm-wave band OAM.