A Low-Complexity Integer Frequency Offset Estimation Scheme Using Combined Training Symbols for OFDM Systems

Abstract

In orthogonal frequency division multiplexing (OFDM) systems, an integer part of a frequency offset (IFO) that causesambiguity in data demodulation is estimated generally by comparing correlations between the received and local signalsfor IFO candidates. In this paper, we propose an IFO estimation scheme that provides a tradeoff between the estimationperformance and the computational complexity including a conventional scheme as a special case. In the proposedscheme, template signals are formed by combining frequency-shifted training symbols, allowing the receiver to reducethe number of IFO candidates in the estimation process. Numerical results illustrate the tradeoff of the proposed scheme:The proposed scheme exhibits a tradeoff between the correct estimation probability and the computational complexitytaking the number of the training symbols used to construct the template signal as a parameter.