Low-Cost Low-Power ASIC Solution for Both DAB+ and DAB Audio Decoding

摘要

DAB+ is the upgraded version of digital audio broadcasting (DAB). DAB and DAB+ coexist in many countries, so receivers are required to be compatible with both standards. In this paper, a solution integrating an MPEG1-LayerII (MP2) decoder and an advanced audio coding (AAC) low-complexity (AAC LC) decoder is proposed to provide basic audio decoding for both DAB and DAB+. It also utilizes simple methods to improve high frequencies and stereo quality instead of complicated spectrum band replication and parametric stereo. A highly integrated low-power audio decoder design compatible with DAB/DAB+ and using a purely ASIC approach is presented. As a result of the system structure optimization and hardware sharing, the audio decoder is fabricated in 1P4M 0.18-$mu{rm m}$ CMOS technology using only 3.2 ${rm mm}^{2}$ silicon area (including 147 456 bits RAM and 170 496 bits ROM). The power consumption of the audio decoder is 10.4 mW for DAB audio decoding and 8.5 mW for DAB+ audio decoding. Laboratory and field tests show that the function is correct and the audio quality is good for receiving both DAB and DAB+. The audio decoder is thus proven to be a low-cost low-power solution for the two existing DAB standards.