Analog and RF Interference Mitigation for Integrated MIMO Receiver Arrays

Over the past decade, we have witnessed the maturation of silicon-based phased array technology, which has started to make an impact on commercial and military wireless applications. Over the next decade, driven by the development of next-generation wireless communication networks, we will see the maturation and impact of large-scale multiple-input-multiple-output (MIMO) technology. MIMO receiver arrays exploit digital array signal processing, and consequently are exposed to interference in the analog and radio-frequency (RF) front ends. The absence of analog/RF interference mitigation in traditional digital MIMO receiver arrays results in designs with high-dynamic-range and power-hungry analog and RF receiver front ends and analog-to-digital converters. This paper describes recently developed techniques for spatio-spectral interference mitigation in the analog and RF domain for digital MIMO receivers. The techniques proposed are flexible; tunable across operating frequency; scalable; present low cost, size, and power consumption overheads; and are experimentally validated through a 0.1-1.7-GHz four-element receiver front-end array integrated circuit (IC) prototype in 65-nm complementary metal-oxide-semiconductor (CMOS) technology.