Stady On Multi-frequencychannel Interference Alignment And The Application In Millmeter Wave Communication

As a novel of interference management technology,interference alignment (IA) has gained extensive attention and deep research in the field of wireless communication system because of its ability to obtain network performance much better than that of traditional communication technology and greatly enhance the network capacity of wireless communication system. At present, most of the implementation of interference alignment technology model is based on spatial signal space expansion. However, due to the promising future of high-rate millimeter-wave band of high-speed wireless communication network to meet the frequency domain interference alignment technology on the frequency channel non-correlation requirements, multi-frequency channel interference alignment technology research more and more attention. In this paper, the following research is carried out for the multi-channel and single-stream interference network in the frequency domain:1) For the multi-frequency channel interference alignment system, the user capacity of the conclusion has been clearly demonstrated. because of the frequency domain interference alignment system channel matrix is the diagonal random matrix, unlike the multi-antenna MIMO interference network which have generalized random channel matrices. The structure of the solution space of the multi-frequency channel interference alignment has its unique structural characteristics. In this paper, a multi-peak global search algorithm based on particle swarm optimization (PSO) is proposed to solve the problem of multi-channel single-data interference. The algorithm enhances the global search ability by projecting the velocity vector on the plane of the position vector, and adds the learning search along the direction of the gradient of the objective function to improve the convergence speed and the global optimization of the algorithm on the basis of the standard particle swarm optimization. The numerical simulation results show that the new algorithm can obtain better network rate performance than the existing algorithms.2) In order to give full play to the potential of high-frequency spectrum utilization in frequency-domain interference alignment, this paper attempts to apply interference-alignment technology to millimeter-wave wireless communication systems, which are attracting much attention in academia. Firstly, the feasibility of the application of the interference alignment technology based on time-domain, spatial-domain and frequency-domain is discussed in the millimeter-wave system. The ultra-wide bandwidth spectral resource of the millimeter-wave system can satisfy the independent fading characteristics between different frequency channels and meet the requirement of channel independence. Therefore,this paper presents a frequency interference alignment implementation scheme for 60GHz millimeter wave wireless communication system model.In the scheme the channel model of 60GHz millimeter-wave short-range communication at intensive office scene is modeled as the Rice channel,and based on sub-array partition, channel Matrix is equivalent to a diagonal matrix for frequency domain interference alignment. Numerical simulation results show that the proposed scheme can effectively suppress the energy of inter-user interference signals in 60GHz millimeter-wave system and improve the performance of the system to obtain better channel capacity.