Patent ID: 7443783
Filing Date: 2008-10-28
Classification: H04L

Abstract:
1. A receiver for an orthogonal frequency division multiplex radio signal in which a carrier frequency is modulated by sub-carrier signals (S I ) coded with data, the receiver comprising analogue signal processing means for combining a received radio frequency signal with at least one reference frequency signal and producing analogue signals (I-Rx, Q-Rx) in phase quadrature whose frequencies are functions of frequency differences between said radio frequency signal and said reference frequency signal, analogue-to-digital converter means for converting said analogue signals to phase quadrature digital signals (x I (n), x Q (n)), and digital signal processing means including demodulator means for reproducing said sub-carrier signals, mismatch compensation means for combining each of said reproduced sub-carrier signals (R I ) according to a mismatch coefficient (A(k)) with another of said reproduced sub-carrier signals (R −I ) whose sub-carrier frequency is symmetrical therewith and compensating for offset (Δf c ) of said reference frequency relative to said carrier frequency, and decoding means for recovering data from the reproduced and compensated sub-carrier signals, characterised in that said compensation means is arranged to combine each of said reproduced sub-carrier signals (R