Christian Mayer

A robust GSM/EDGE transmitter using polar modulation techniques

A key property of polar modulator systems is the matching between amplitude and phase path. This paper shows how mismatches between these paths degrade performance and introduce difficulties in designing GSM/EDGE systems. A transmitter overcoming these problems is presented. The chip has been implemented in a 0.13mum CMOS technology, with a nominal margin of 7 dB to the critical 400 kHz specification and a transmit EVM of 2.5%

Digital RF CMOS transceivers for GPRS and EDGE

A GPRS RF solution using sigma-delta modulation and an EDGE RF solution using digital polar modulation are presented. The single-chip, quad-band transceivers have been implemented in a 0.13 /spl mu/m CMOS technology. The lock-in time of the sigma-delta modulator with integrated loop filter is less than 120 /spl mu/s with a phase error of 1.2/spl deg/ RMS and an output power of 3.5 dBm; it is fully compliant to the GSM specification. The EDGE transceiver shows a nominal margin of 11 dB to the critical 400 kHz specification with a transmit EVM of 2.5%.