The Influence of Test Signal Selection on the of Impulse Response Estimation in Communication Channel

Modern wireless networks operate in a complex interference environment that requires to develop continuous technical solutions in order to improve the reliability and efficiency of communications. In wireless telecommunication systems, methods for transmitting information flows using multiple parallel orthogonal carrier frequencies are actively applied – for example, OFDM technology. When inter-symbol interference is detected, processing OFDM signals using classical methods or the algorithm «reception «as a whole» with element-wise decision-making requires knowledge of channel parameters. Specifically, the impulse response can be estimated by use of the regularization method, and the results of estimation with the use of the regularization method for «bad» channels with intersymbol interference can be improved through optimal selection of test combinations. To confirm all of the above, simulation using statistical trials for basic OFDM technology as well as applicable to N-OFDM, COFDM, and OFDMA technologies was performed.