A broadband 470–862 MHz direct conversion CMOS receiver

This work presents an integrated ultra high frequency (UHF), broadband direct-conversion receiver. The receiver integrates a single-ended RFVGA, an on-chip single-to-differential balun, a current-mode passive mixer, and a combination of continuous and discrete-time baseband filter with built-in anti-aliasing. Targeted to operate between 470-862 MHz, the receiver achieves a noise figure of 7.9dB, an IIP3 of -8dBm at maximum gain and an IIP3 of +2dBm at 9dB RF attenuation. The gain- and frequency-programmable baseband section implements an 8^th order inverse chebyshev low pass approximation achieving >42dB attenuation at an offset of 1.75 MHz for the 4 MHz frequency setting. Overall, the receiver consumes 120mW from 1.8V analog/2.5V digital dual supply and occupies 2.14mm² in IBM 0.18μm RFCMOS technology.