  A practical $2^m$-ary polar coded modulation (PCM) scheme with optimal
constellation labeling is proposed. To efficiently find the optimal labeling
rule, the search space is reduced by exploiting the symmetry properties of the
channels. Simulation results show that the proposed PCM scheme can outperform
the bit-interleaved turbo coded modulation scheme used in the WCDMA (Wideband
Code Division Multiple Access) mobile communication systems by up to 1.5dB.
