A 2–18 GHz Compressed Sensing Receiver With Broadband LO Chain in 0.13- $\mu$ m BiCMOS

We present an integrated 2-18 GHz four-channel compressed sensing receiver (CSRX), which performs a 128.5× sub-Nyquist acquisition with 36-Gb/s pseudorandom bit sequence (PRBS) generators in 0.13-μm BiCMOS. The integrated four-channel CSRX consists of broadband receiver chains, each of which includes a distributed RF buffer that operates as an active balun at 2-18 GHz, followed by a double-balanced passive mixer for high local-oscillator (LO)-to-intermediate frequency (IF) isolation at the IF band, and a 700-MHz variable gain amplifier (VGA). Four independent 36-Gb/s PRBS generators are integrated to perform the compressed sensing by mixing the PRBS signal as the random modulator. To deliver the generated wideband PRBS signal to the mixer, the LO driver conducts band-equalization by applying a shunt-shunt feedback amplifier to compensate for the high-frequency degradation of the PRBS LO tones through the LO generation stage. The chip consumes 195 mA per channel with a 2.5-V supply.