Frequency Offset Estimation in the Presence of IQ Imbalance for a DVB-T Receiver

This paper investigates the frequency offset estimation in the presence of IQ imbalances for a direct-conversion receiver. Three frequency offset estimation schemes applicable to DVB-T are considered. Of the three estimation schemes, one is based on the cyclic prefix, and the other two use pilot carriers. One of the pilot based adaptive frequency offset estimation schemes are based on complex least mean squares, and the other is based on complex recursive least squares. The effects of IQ imbalances on all three frequency offset estimation schemes are discussed through analysis and simulations. Finally, all three methods are compared and contrasted using the mean squared error performance and computational complexities