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Timing and Ranging Models Based on OFDM Synchronization

Orthogonal frequency division multiplexing (OFDM) modulation needs better synchronization performance than conventional single carrier modulation schemes since the former is very sensitive to time and frequency variations. So a ranging technology can be established on highly precise timing measurements of OFDM synchronization. The principles of ranging based on frame synchronization is studied that can be applied into OFDM broadcasting systems. The timing models for OFDM ranging are set up and the observational models are presented. Then the ranging performance is analyzed by calculating the Cramer-Rao lower bound of the symbol offset that is relative to the pseudo-range accuracy in OFDM ranging systems.