stems without BwPIC, and the results also show that the algorithm converges with no more than two iterations. Conclusion A single subband matrix form f-OFDM system is modeled in this chapter, in which all the linear convolution operations were converted into matrix multiplications to derive a well-channelized signal. Based on this model, the analytical expressions of the in-band interference, including ICI, f-ISI, and b-ISI, were derived, and the interference-free con- dition was developed. In addition, a low-complexity FEQ algorithm - BwPIC - to cancel the in-band interference is presented. As the simulation results show, the analytical inter- ference power calculated from the analytical expression matches the simulation results, validating the analytical model established. The proposed BwPIC effectively cancels the interference signal and significantly improves the BER performance. To conclude, the work presented in this chapter provides a useful reference and valuable guidance for the practical deployment of the waveform in wireless systems. 2.A Appendix 2.A.1 Derivation of Zk Substituting rk in Eq. (2.12) with its expression in (2.9), followed by replacing Sk with its expression in (2.5), we obtain 2.C Appendix P'Xk+1) (2.A.1) where Wk = Q"Wk-1+Q"Wk+QWk+1is the filtered AWGN signal. To simplify (2.A.1) and eliminate redundant terms, we introduce the following proper- ties: 2.A.1 The product of the two strictly upper triangular matrices is zero, and the product of the two strictly lower triangular matrices is also zero. 2.A.2 The product of Pu/Qu and Hm is a strictly triangular matrix A with Aij = 0, when proof can be found in Appendix 2.3.1. We have Q"H" = 0 under the Property 2.A.1, Q"HmPu = 0 and Q'Hmp = 0 under Prop- erties 2.A.1 and 2.A.2, thus obtaining a simplified version of Zk (2.A.2) 2.B Appendix 2.B.1 Proof of OpreBeing a Strict Upper Triangle As = the same approach as in Appendix 2.3.1, we can prove the following: (i) the product of Q"Hmpm is a strictly upper triangular matrix of which only the top