Design of a low power GPS receiver in 0.18 μm CMOS technology with a ΣΔfractional-N synthesizer

Abstract

A 19 mW highly integrated GPS receiver with a ΣΔfractional-N synthesizer is presented in this paper. Fractional-N frequency synthesizer architecture was adopted in this work, to provide more degrees of freedom in the synthesizer design. A high linearity low noise amplifier (LNA) is integrated into the chip. The radio receiver chip was fabricated in a 0.18 μm complementary metal oxide semiconductor (CMOS) process and packaged in a 48-pin 2 mm×2 mm land grid array chip scale package. The chip consumes 19 mW (LNA1 excluded) and the LNA1 6.3 mW. Measured performances are: noise figure<2 dB, channel gain=108 dB (LNA1 included), image rejection>36 dB, and −108 dBc/Hz @ 1 MHz phase noise offset from the carrier. The carrier noise ratio (C/N) can reach 41 dB at an input power of −130 dBm. The chip operates over a temperature range of [−40, 120] °C and ±5% tolerance over the CMOS technology process.