OFDM-WLAN receiver performance improvement using digital compensation techniques

Zero-IF receiver architectures are preferred over superheterodyne solutions since their better integration capabilities result in cost advantages. However, zero-IF receivers present a set of analog non-idealities to the system designer. Among those, DC offsets, I/Q mismatch, phase noise, and limited dynamic range are the most challenging ones. For each or these imperfections, we propose digital compensation techniques that can either improve receiver performance considerably or allow a relaxation of the analog front-end specifications. Simulation results are presented for IEEE 802.11a-compliant receiver specifications.