17.3 A 60GHz on-chip linear radiator with single-element 27.9dBm P<inf>sat</inf> and 33.1dBm peak EIRP using multifeed antenna for direct on-antenna power combining

Abstract

A major challenge for low-cost silicon-based mm-wave wireless links, e.g., for the 5G communication, is to provide large transmitter (Tx) output power (P <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">out</sub> ) with high energy efficiency and linearity from a limited supply voltage, so that the high path loss and limited link budget at mm-wave can be compensated. Power combining is often required for high-power mm-wave Tx. The existing power-combining techniques are mainly in two categories. Passive on-chip/on-package networks can combine P <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">out</sub> from multiple power amplifiers (PAs) and feed a single antenna port [1-4]. However, lossy power combiners and large impedance transformation ratios degrade the total P <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">out</sub> delivered to the antenna and lower the Tx efficiency. Alternatively, spatial power combining using antenna array increases the total EIRP but at the expense of a large array-panel size. Moreover, a large antenna array often presents an exceedingly narrow (or even pencil-sharp) beamwidth; this complicates the Tx/Rx alignment and is challenging for dynamic and mobile mm-wave applications, such as 5G links. In addition, adding silicon lens enhances EIRP but increases cost and packaging complexity.