Certain investigations on estimation parameters and compensating methods for multi relay cooperative networks

Abstract

The increasing interest of using Orthogonal Frequency Division newlineMultiplexing (OFDM) systems for digital broadcast wireless applications are newlinemainly due to its broadband characteristics. The multi carrier concept in newlineOFDM systems leads to synchronization errors. These synchronization errors newlinecan be time, carrier frequency, sampling frequency and phase offsets. One of newlinethe offset synchronization method, maximum likelihood method is applied for newlineestimating the time and carrier frequency offsets and for decoding purpose at newlinethe receiver end. It uses the Expectation Conditional Maximization (ECM) newlineand Space Alternating Generalized Expectation (SAGE) algorithms for newlineestimation. newline