Modeling And Parameter Estimation For Wideband Channel System

The wideband mobile communication has became a new round international focus of technical and industrial competition. Aim at a new generation of broadband mobile communication network of our country with the stereotyped research and application requirements of the wideband radio mobile channel and the complex environment propagation properties, establish radio channel model which is suitable for the communication propagation environment of our country the environment of outdoor including city and suburbs, analyze the correlation properties of model, mainly involving the spatial, time and frequent properties of channel, and propose the application solution of the wideband mobile channel model and the extract method of model parameters.The results of study and main idea in the paper are given as follows:(1)Provide the application method and channel model of wideband mobile network design and planning which is suitable for the typical environment of our country. There are many classic models for MIMO channel at home and abroad, a model called the geometrical one-ring model for MIMO channel has been used extensively. On the base of the primary one-ring model for MIMO channel, we obtain the simulation model with the method of sum-of-sinusoids (SOS), and analyze the spatial-temporal-frequency properties based on the reference. In consider of the wideband system, we also extend the one-ring channel model to the one-ring model for MIMO channel with respect to frequency-selectivity by partitioning the scattering ring into L pairs of delay slices with relevant paths, and give a corresponding analysis at last.(2)From the study of parameters-MIMO time delay, the Doppler frequency, Angle-of-Arrival, Angle-of-Departure and Angular spectrum analysis in time domain, frequency domain and spatial domain of wideband channel model, we obtain the extractive technology and application method of parameters. Among the deterministic parametric estimation (DPE) methods, the expectation-maximization (EM) algorithm has been used for either delay or azimuth estimation. The SAGE (space-alternating generalized EM) algorithm, which is an extension of the EM algorithm, has been applied for joint delay and azimuth estimation in time-invariant environments as well as for joint delay, azimuth, and Doppler frequency estimation in time-variant environments. The SAGE algorithm is a joint maximum likelihood estimation which computes parameters of electromagnetic wave with separated iterative maximum process. The paper mainly analyzes the fundamental principle of SAGE algorithm in jointly estimating the channel parameters, verifies the feasibility and validity by constructing the multipath environment of MIMO channels, and provides an application in theory with the practical measurement data.