High-Resolution Channel Parameter Estimation for MIMO Applications



A high-resolution estimation scheme called ISI-SAGE algorithm has been designed that performs joint estimation of the relative delay, the Doppler frequency, the direction - i.e. azimuth and co-elevation angles - of departure, the direction of arrival and the complex attenuation of propagation paths between the transmitter and receiver sites in mobile radio environments. The acronym ISI (Initialization and the Search Improved) emphasises the fact that the initialization and the search procedures required for finding maximums in the maximization (M) step of the SAGE (Space-Alternating Generalized Expectation-maximization) algorithm are optimised in order to enhance convergence and path detection probability. Extensive applications of the ISI-SAGE algorithm in experimental investigations demonstrate its high potential for detailed propagation investigations. Recently, the ISI-SAGE algorithm has been extended to estimate the polarization matrix. Experimental investigations in line-of-sight and non-line-of-sight pico-/micro-cellular environments show that the polarization characteristics of individual propagation paths can be extracted and related directly to the types of interaction that the waves experience along their respective paths, such as reflection, diffraction, scattering. This detailed insight into the propagation mechanisms is of paramount importance for the design of (1) realistic stochastic models for optimisation and performance simulation of communication systems equipped with multiple-element transmit and receive antennas as well as (2) accurate deterministic models for field prediction. (Xuefeng Yin, Bernard H. Fleury)
Effektiv start/slut dato01/01/200231/12/2002