A Novel Preamble Design for Channel Estimation in Mimo- Ofdm Systems Resulting in Enhanced Throughput

Multiple Input Multiple Output (MIMO) system combined with orthogonal frequency division multiplexing (OFDM) provides a reliable solution for enhanced data rate next generation wireless systems as MIMO produces additional parallel channels in spatial domain which allows high data rates to be achieved without extra bandwidth and transmitted power. While OFDM provides high bandwidth efficiency and robustness to multipath fading due to orthogonal subcarriers that convert frequency selective channel into parallel frequency flat channels. Channel estimation is integral part in coherent MIMO-OFDM systems. Burst communication system utilizes data aided channel estimation algorithms due to their fast convergence and accuracy relative to blind estimation algorithms. Data aided schemes in MIMO-OFDM employ periodic transmission of training data from transmitter for channel estimation at the receiver. In MIMO-OFDM systems higher number of transmit/receive antennas causes a bigger overhead for channel estimation. This paper proposes novel preamble design with low overhead for channel estimation. Simulation results and analysis of time based channel estimation algorithm resulting in spectrally efficient MIMO-OFDM system have also been provided.