Synchronization for RF carrier frequency hopped OFDM: analysis and simulation

In this work, we apply RF carrier frequency hopping to orthogonal frequency division multiplexing (FH-OFDM) and study the hop rate capability using realistic performance of signal acquisition/synchronization of the unknown time and frequency offset parameters. OFDM synchronization is a challenging task without RF carrier hopping due to OFDM´s sensitivity to time and frequency offsets. Given sufficient synchronization estimation performance is achieved, our objective is to determine the hop rate capabilities for OFDM using two different data-aided synchronization approaches. The first method is based on sending information in a preamble before the OFDM payload symbol. The second method embeds known synchronization information directly into the OFDM symbol stream. Using differential QPSK-OFDM modulation and spectral efficiency greater than 1 bps/Hz, results indicate that sufficient synchronization performance can be achieved for hop rates greater than 6 and 1 khops/sec for the preamble- and embedded-based synchronizers, respectively.