O.N. Chirkov – Senior Lecturer, Department Radio Equipment Engineering and Manufacturing, Voronezh State Technical University
This article proposes an efficient algorithm for the dynamic distribution of pilot signals (DPA) for estimating a radio channel in multi-antenna systems with orthogonal frequency multiplexing MIMO-OFDM. The basic idea of DPA is to assign pilot signals to the appropriate subcarriers for an arbitrary number of transmit and receive antennas. A simulation study of the proposed and existing algorithms for uniform and dynamic distribution of pilot signals has been carried out.
The most common approach used in modern standards for wireless broadband data transmission with orthogonal frequency multiplexing (4G, LTE) for assessing the state of a radio channel is transmission along with information signals - pilot signals. Signal discrimination techniques are usually designed to evenly distribute pilot signals (UPA) without any prior knowledge of the communication channel. In addition, these channel estimators are tuned to minimize the mean square error (MSE) of the estimates, and not to optimize intersymbol errors. Optimizing the root mean square channel estimation error is not equivalent to optimizing the SER. It has been shown that BER performance can be significantly improved by using dynamic DPA pilot distribution algorithms based on iterative search for SISO-OFDM systems.
The simulation results showed that the proposed method will improve the performance of the intersymbol SER error rate in MIMO OFDM systems.
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