A very low power and high-quality signal transmission baseband LSIC for personal communications-advanced signal processing and one-channel integration

Abstract

This paper proposes a very low power consumption (2V operation) one-chip baseband LSIC for personal communication terminals. It is composed of a /spl pi//4 QPSK modem, a TDMA-TDD controller, an ADPCM codec and a LAPDC controller. The developed CMOS LSIC completely meets the PHS (Personal Handy Phone System) standard. By employing a novel coherent demodulator and an ADPCM codec with a click noise suppressor, 6dB higher-quality voice transmission has been realized in fading environments. Moreover, the novel circuit configurations of the modem, the ADPCM codec, the TDMA-TDD controller and the LAPDC controller make it possible to reduce significantly the power consumption of the baseband circuits of personal communication terminals.