A Highly Integrated Dual Band FMCW Radar Receiver for Indoor Positioning Applications

This work presents the design of a highly integrated dual band frequency modulated continuous wave (FMCW) radar receiver (RX) at the 2.4 and 5.8 GHz industrial, scientific and medical bands. As opposed to earlier versions of this work, baseband low pass filtering is performed by the integrated variable gain amplifier (VGA) thus eliminating the need for an off-chip low pass filter (LPF) together with the required chip pads needed for this external filter. Fabricated on an IBM 0.18 μm BiCMOS process as part of a dual band FMCW radar transceiver (TRX), the measured RX performance is in good agreement with simulations and measurements from previous RX versions with the external LPF achieving a dynamic range of more than 50 dB and a baseband signal-to-noise ratio (SNR) of around 18 dB at -70 dBm radio frequency (RF) input power and an input-referred 3
^rd
order intercept point (IIP3) of around -7 dBm. To the best of the author's knowledge, with a chip area of 2.4 mm
²
, this filterless dual band FMCW radar TRX has the highest level of integration reported in the literature.