A 2.4-GHz ISM-transmitter IC with novel quadrature clock generation technique for a localization application

The design of a fully integrated 2.4-GHz ISM-band transmitter for a localization application is presented. The signal path includes DAC, anti-alias filter, IQ-modulator and power amplifier. The clock generation part comprises voltage controlled oscillator, phase-locked loop and a quadrature clock generator. A novel quadrature clock generation scheme is proposed and described in detail. It reduces phase errors significantly and avoids the VCO pulling problem. The circuit was fabricated in a 0.35 /spl mu/m SiGe BiCMOS technology.