Rate And Beamwidth Adaptation Based Protocol Design Of Mm Wave Communication System

In order to solve the spectrum bottleneck problem in wireless communication,millimeter wave has become a transmission carrier for the next generation communication,with its large spectrum resource(30 GHz to 300 GHz).However,due to its unique signal propagation characteristics,the millimeter wave link attenuation is very serious.To compensate for such loss,researchers proposed three beamforming techniques to form directional gain to compensate for this high propagation path loss.Although this directionality also eliminates interference between users,it also brings corresponding problems:(1)The instability of the millimeter-wave channel urgently needs to be improved to achieve robust transmission.(2)highly directional link is considered as a pseudowire,so that the third party node cannot perform carrier sensing like Wi-Fi during directional transmission,thus it is easy to cause conflicts.(3)When the number of antennas is fixed,in a dense network,the limited number of beams cannot effectively increase the network capacity.How to skillfully solve these problems leads us to think about the millimeter wave physical layer and MAC layer network architecture.We first consider how to improve the stability of the channel so that it is not affected by changes in the surrounding environment.By using rateless code to optimize the rate adaptation protocol of millimeter wave communication,highspeed and stable transmission of multimedia data in millimeter-wave communication systems can be realized.Second,we adaptively adjust the appropriate beamwidth based on system throughput to cover as many users as possible without inter-beam interference.Finally,we designed a millimeter-wave multiple access technology,which uses a flexible constellation diagram to achieve multiplexing in constellation dimensions,thereby encourage more users to transmit concurrently within same beam.The simulation results show that,compared with the traditional rate adaptive coding method,our designed fine-grained wireless video streaming scheme under different channel conditions,such as additive white Gaussian noise channel,flat fading channel,frequency selective fading channel,a more stable transmission can be achieved.Even under the influence of the Doppler effect,good performance can be maintained.Secondly,our proposed beam adaptation multiple access architecture not only improves network capacity but also guarantees link transmission quality compared with fixed beamwidth.