Abstract
In a 16QAM communication system, its carrier frequency offset (CFO) can be estimated by employing 4th power method if the 16QAM has 90-degree rotational invariance and the phase ambiguity can be removed by differential encoding. In this letter, we propose a new two-level differentially encoded 16QAM (TD16QAM) design which is suitable for tackling the CFO problem. The proposed TD16QAM is superior to the previously known TD16QAM in the bit-interleaved coded modulation (BICM) system corrupted by CFO.