W-Band Endfire 2-D Phased-Array Transmitter Based on ×9 CMOS Active Multiplier Chips

In this article, we propose a scalable approach for a $W$ -band 2-D beam steering transmitter based on CMOS active frequency multiplier chips. Stacking of PCBs containing linear-phased arrays with endfire antennas is used with $X$ -band power splitting and phase control. The antenna design is discussed, explaining the choice of the SIW fed antipodal linearly tapered slot antenna (ALTSA). The concept is demonstrated in the 90–100 GHz bandwidth with $1\times 2$ , $1\times 4$ , and $2\times 2$ arrays, achieving up to 29.4 dBm EIRP and ±10° of beam steering. Measurement results show excellent agreement with simulations, demonstrating the possibility of scalable 2-D phased arrays in $W$ -band with low-cost small silicon area consumption.