A Wideband IF Receiver Module for Flexibly Scalable mmWave Beamforming Combining and Interference Cancellation
Large-scale phased arrays need to combine weighted signals from multiple sub-arrays either in analog or in digital domain. Sub-arrays are preferably implemented modularly with integrated circuits placed next to the associated antennas. In order to enable flexible and scalable combining networks of several mmWave sub-arrays, this paper presents a wideband receiver module that provides the cartesian combining of beamforming weights for one sub-array at IF. Furthermore, it allows interference cancellation between sub-arrays or combining multiple sub-arrays. It also provides filtering before ADCs to support current and foreseeable 5G channel bandwidths up to 800MHz. The receiver is operating at 2–4GHz IF frequency range and has more than 400MHz baseband bandwidth, a noise-figure of 5.5dB, -6dBm 1dB compression point and +3dBm in-band IIP3. In addition, over-the-air measurements are performed, showing 26dB of interference cancellation between the sub-arrays. The prototype is implemented using 45nm CMOS PDSOI.