The Research On Antenna Array Technology In Millimeter-wave Communication

Millimeter-wave communication has been adopted by 5G system for their large capacity and high transmission quality.And large-scale antenna array and beamforming technologies have become key components in 5G system.Array antenna technology through the antenna layout,access to flexible beam control and high signal gain,can compensate for the millimeter wave communication high path loss.This paper focuses on the millimeter-wave communication array antenna technology.It focues on four aspects: manifold design of large-scale antenna array,beamforming,millimeter-wave channel estimation and channel tracking.The main points of the paper are as follows:(1)The research of large-scale antenna array manifold design in millimeter wave communication,including planar array,coprime array and three-dimensional array.The derivation of the channel matrix in the millimeter-wave system leads to the conclusion that the channel capacity is affected by the array manifold.The factors affecting the array manifold,such as the number of antennas,the distance between antenna elements and the number of layers,are also studied.(2)This part mainly study the beamforming technology in millimeter wave communication system.First of all,we study the 3c codebook and the N-phase codebook stipulated in the IEEE 802.15.3c standard.Aiming at the problem that the beam sidelobe level is too high based on the above two codebooks,this section proposes to apply six commonly used window functions such as uniform window,binomial window,Hamming window and Gaussian window to the codebook Matrix method,thereby obtaining better beam performance.In addition,3c codebook and circular array codebook training mechanism is also studied.(3)For the channel estimation problem in millimeter-wave system,this section divides the channel estimation problem into the path-fading coefficient estimation and the Direction of Arrival estimation(DOA)according to the ray tracing model.(MUSIC)algorithm,a Propagator Method(PM)algorithm,an Estimation of Signal Parameters via Rotational Invariance Techniques(ESPRIT)algorithm and ESPRIT algorithm under the coprime array.(4)To study the channel tracking algorithm of moving target in millimeter-wave system,the angle of incident wave of target signal source is regarded as a function of time in this section.To avoid the step of eigenvalue decomposition with large time complexity,the PAST algorithm and PASTd algorithm quickly obtains real-time signal subspace for the subsequent use of the angle estimation algorithm.