Two linear intercarrier interference cancellation techniques in ofdm systems over multipath channels
多径信道下OFDM系统中的两种线性载波间干扰抑制技术

InterCarrier Interference (ICI) is an important factor degrading the performance of Orthogonal Frequency Division Multiplexing (OFDM) systems. Two linear ICI cancellation techniques, Frequency RAKE (F-RAKE) and frequency equalization (F-FIR), with different length of delay-line, L, are studied in this paper. Assuming that the channel information is known in the receiver and MMSE criterion is adopted for F-FIR, results show that F-RAKE has about 2-5dB Carrier-Interference-Ratio (CIR) achievement than standard receiver in case of L=3. Meanwhile, F-FIR has about 2-7 dB CIR achievement. And the CIR performance gains of the two schemes decrease with increment of L. Also, the computational complexity of F-FIR is L times than that of F-RAKE. Thus, the tradeoff between complexity and performance in the engineering can be reached by selecting the length of delay-line and receiver scheme.