Digital I/Q demodulation and digital filtering for a DAB receiver

A digital I/Q demodulator followed by two paths of decimation is presented as a solution to improve the integration level of a DAB receiver. This digital system was designed to work with a bandpass /spl Sigma//spl Delta/ modulator. So that the digital filters attenuate both quantization noise and adjacent channels. An integrated circuit was fabricated in 0.25-/spl mu/m CMOS technology for a working frequency of 30.720 MHz. The power consumption is equal to 5.6 mW for a 1.0-V supply voltage and the chip size is about 6.8 mm/sup 2/ including pads.