Multi-port mm-Wave Transceivers and Antenna Interfaces: Towards Programmable mm-Wave Front-ends

Abstract: Future mm-Wave systems are expected to operate in a complex and heterogeneous environment extending from the electromagnetic propagation channels right up to the network layers. As disjointed spectral bands open up across 28-100 GHz for 5G applications and beyond, spectrally agile, robust mmWave front-ends that can allow dynamic reconfiguration in large scale mmWave MIMO arrays can have a transformative impact in spectrum efficiency and deployment of such 5G systems. While this involves a series of challenges from the antenna to the transceivers I will highlight two specific directions in this talk. These emerge through a multi-port transceiver and multi-port antenna framework that allow each element to assume properties distinct from classical array architectures. Firstly, I will discuss the challenges of enabling a transmitter front-end particularly the power amplifier for such a spectrally-agile mmWave system. I will discuss multiport architectures that can allow simultaneously broadband, high power and high back-off efficient transmitter front-end, properties that typically strongly trade-off with each other. In the next part of the talk, we will discuss how such multi-port transceivers can be co-design and co-integrated with multi-port antennas to allow such spectrally-agile architectures, in addition to extremely high bandwidths, these architectures allow element level programmability needed for multi-band periodic arrays. These include the ability to reject interferers passively directly at the element antenna surface, reconfigure individual antenna patterns, and allow frequency, spatial, pattern and polarization diversity in scalable arrays.