Analysis and power evaluation of window‐stopped parallel turbo decoding for LTE rate matching

Abstract

Long-term evolution (LTE) adopts rate matching (RM) to reach high-speed data transmission. According to the LTE hybrid automatic repeat request scheme, the receiver can correct multiple transmission data with distinct code rates. Here, the window-stopped (WS) criterion is reinvestigated for the single-binary (SB) turbo code in LTE RM. The parallel SB WS turbo decoding for LTE RM with distinct parameters is analysed in terms of window stopping rate, kernel stopping rate, and correcting performance. Experimental results reveal that the early termination technique does not work well for high-code-rate decoding. However, the SB WS criterion significantly achieves up to 19% window stopping for decoding large codeword blocks and 37% kernel stopping for decoding small codeword blocks. Moreover, the SB WS criterion is implemented within a parallel turbo decoder for LTE RM using a 90 nm CMOS process. The evaluation results show that the power dissipation of the implemented WS parallel turbo decoder can be significantly reduced by 17% with a 0.7% area overhead for high-code-rate decoding and high channel quality.