Comments on “Estimation of Carrier Frequency Offset With I/Q Mismatch Using Pseudo-Offset Injection in OFDM Systems”

In a recently published paper, an estimation algorithm of carrier frequency offset (CFO) with I/Q mismatch was proposed. Errors in the derivation of the algorithm show that its precision can only be asserted in the case of relatively small I/Q mismatch. Averaging the intermediate variables among one short preamble period improves the estimation accuracy under conditions where I/Q mismatch is large.