A 20-mA-receive, 55-mA-transmit, single-chip GSM transceiver in0.25-μm CMOS

This paper presents a low-power 900-MHz GSM transceiver developed in a 0.25-μm CMOS technology. The superhet receiver, with a single intermediate frequency at 71 MHz, has an overall worst case noise figure of 8.1 dB, including all filters. The overall gain can be digitally controlled over 98-dB range. The receiver consumes only 19.5 mA from the 2.5-V voltage supply while achieving the required blocking and intermodulation performance. The direct conversion transmitter has a fully integrated phase shifter and provides a 2-mW signal to the power amplifier with a low level of spurious emissions. The transmitted Gaussian minimum shift keying signal has an RMS average phase error <2°, and the overall current consumption of the transmitter is 55 mA