Publicou 12 edições por ano
ISSN Imprimir: 0040-2508
ISSN On-line: 1943-6009
Indexed in
CHANNEL ESTIMATION FOR MISO OFDM SYSTEM USING IMPROVED CYCLIC DELAY DIVERSITY
RESUMO
Pilot Aided Channel Estimation (PACE) is a technique used in Orthogonal Frequency Division Multiplexing (OFDM) for high data rate transmission over wireless environment. In block type pilot arrangement, channel at pilot tones can be estimated by Least Square (LS) or Minimum Mean Square Error (MMSE) estimation. In conventional Cyclic Delay Diversity (CDD) OFDM, the estimation error is high due to non-exploitation of spatial diversity. A novel technique is introduced to make use of spatial diversity in OFDM systems, either applied at the transmitter or receiver or both transmitter and receiver. Spatial diversity can be obtained elegantly using proposed CDD-OFDM without exceeding the guard interval in OFDM systems. This paper deals about a method to choose cyclic delays and proposes an improved CDD-OFDM method which exploits full spatial diversity. Simulation results show that the proposed CDD-OFDM has better mean square error (MSE) than conventional CDD-OFDM.