Orthogonal Codes for MAI-Free MC-CDMA with Carrier Frequency Offsets (CFO)

— The performance of MC-CDMA in the presence of carrier frequency offsets (CFO) can be severely degraded due to multiaccess interference (MAI). It is shown in this work that a properly chosen subset of real Hadamard-Walsh or exponential codes can achieve zero MAI in a CFO environment. For a channel of length L and a number G of power of 2 with G ≥ L, we prove that 1 + log2(N/G) Hadamard-Walsh codewords or N/G exponential codewords can achieve zero MAI under any CFO level. Simulation results are given to corroborate derived theoretical results and evaluate the performance of MC-CDMA with a variable number of users in a CFO environment.

• Type: Conference
• Year: 2006
• Where: GLOBECOM
• Authors: Layla Tadjpour, Shang-Ho Tsai, C. C. Jay Kuo
• Keywords: Carrier Frequency Offsets, CFO Environment, GLOBECOM 2006, N/G Exponential Codewords, Telecommunications