Implementation of BICM-ID Receiver for Coded Modulation in DTMB-A

Abstract

Digital terrestrial television multimedia broadcasting-advanced (DTMB-A) has just been announced as one of the second generation digital terrestrial television broadcasting (DTTB) standard. In comparison with digital terrestrial television multimedia broadcasting (DTMB) standard, DTMB-A has innovations and upgrades in many aspects, including coding and modulation, which are essential modules in DTTB system. Low-density parity-check (LDPC) codes and amplitude phase shift keying constellations with Gray-mapping (Gray-APSK) are adopted. Bit-interleaved coded modulation with iterative demapping (BICM-ID) is also introduced, which is proved capable of obtaining performance gain comparing to conventional independent demapping. However, few quantitative results of the BICM-ID receiver under DTMB-A standard are presented. Comparison between DTMB-A and other DTTB standards is also deficient. In addition, introduction of iterative demapping (ID) makes hardware implementation more complex. Processing and scheduling strategies are different and more hardware resources are demanded, which indicates that more detailed studies are needed. This paper gives quantitative results of BICM-ID and BICM receiver under DTMB-A standard via both performance analysis and simulation, and makes comparison with other DTTB standards. Utilization of hardware resources is also evaluated and presented. The results show that in typical DTMB-A terrestrial broadcasting mode (256 Gray-APSK and 2/3-rate long LDPC codes), BICM-ID receiver brings 0.4 dB gain in the additive white Gaussian noise (AWGN) channel comparing to BICM receiver and its performance is better than those under the same conditions of other standards. Register transfer level (RTL) synthesis from hardware implementation is carried out and shows that limited extra hardware resources are needed to support ID.