A BiCMOS upconverter with 1.9 GHz multiband frequency synthesizer for DVB-RCT application

In this paper, we present an integrated upconversion stage including an integer-N synthesizer in a 0.35 /spl mu/m BiCMOS process. This chip is, to our knowledge, the first integrated circuit for a DVB-RCT application ever published. This standard requires 125 kHz frequency steps in the UHF band and an architecture is proposed to upconvert the 44 MHz IF signal. The realization of a converter stage, composed of a mixer and a synthesizer, based on a multiband VCO (voltage controlled oscillator), is also described. The mixer converts frequencies from 1080-1092 MHz to the UHF band (470-860 MHz). The synthesizer includes a programmable divider, with a dual modulus prescaler, and a multiband LC-VCO, which allows a frequency range of 1550-1952 MHz. A single side band phase noise of -84 dBc/Hz at 10 kHz offset and -122 dBc/Hz at 1 MHz offset have been measured at the synthesizer output. A power conversion gain of 7 dB and a noise figure of 14.9 dB characterize the mixer.