A 85 Mbps low-power DQPSK modem-LSI for advanced wireless access

Abstract

A new differential quadrature phase shift keying modem-LSI uses differential mapping for modulation and baseband delay detector logic for demodulation. The LSI achieves a maximum bit rate of over 85 Mbps and low power dissipation of 67 mW at 80 Mbps with a 3-V power supply. We built an intermediate-frequency (IF)-part test circuit composed of the new modem-LSI, and did a transmission test at IF return. The C/N degradation of this circuit is about 1.7 dB at 75 Mbps.