Partially Information Coupled Bit-Interleaved Polar Coded Modulation for 16-QAM

We investigate the spatial coupling technique for coded modulation schemes. In particular, we design partially information coupled bit-interleaved polar coded modulation (PIC-BIPCM) schemes for Gray-labelled 16-ary quadrature-amplitude modulation (16-QAM) over AWGN channels. In order to improve the error performance of the BIPCM, we propose a method to appropriately choose the coupled information bits between consecutive polar code blocks (CBs). We also derive a closed form expression for the CB error rate of the designed PIC-BIPCM. Simulation results show that the proposed PIC-BIPCM can achieve a considerable gain over the uncoupled counterparts for variable code rates.