A High-Robust Low-IF Bluetooth Receiver With Noise Suppression and Offset Elimination Schemes

A low-intermediate-frequency (low-IF) Bluetooth receiver (RX) is fabricated in 65-nm CMOS, and noise suppression and offset elimination are highly focused. The low-noise amplifier (LNA) has a noise-cancellation feature with opposite polarities. By using offset-immunity schemes, double-balanced quadrature mixer and high-robust complex filter suppress image interferences and I/Q imbalances. Low-complexity dc offset compensation (DCOC) units attenuate noises and offsets of IF modules. Experimental results show that the proposed RX has an active area of 1.2 mm<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> and a power dissipation of 6 mW from a 1.2-V supply. The prototype RX also achieves a noise figure (NF) of 4 dB and a sensitivity of −96 dBm under a 0.5-MHz IF and 1-Mb/s data rate (DR).