An effective scheme to improve performance of OFDM-based system

This paper presents an effective scheme to improve performance of OFDM-based system. Besides synchronization errors, DC offset and mismatch of in-phase/quadrature (I/Q) modem are two major implementation effects resulting distortion of OFDM symbol. By utilizing digital IF technique combined with post-compensation in frequency domain, DC offset and intercarrier interference (ICI) caused by I/Q imbalance can be entirely eliminated. This scheme is illustrated with WLAN IEEE802.11a system.