Coherent J-Band radiating arrays based on ×27 CMOS activemultiplier chips

This paper presents a hybrid design of 1 × 2 and 1 × 4 arrays operating in 0.277-0.292 THz on 65 nm Complementary metal-oxide-semiconductor (CMOS) technology. Each of the chips has an X-band input with 3 ×3 multiplier stages and connected at the output to an on-chip ring antenna. A wideband microstrip Wilkinson four-way and two-way power dividers have been developed on a multilayer printed circuit board to feed the array elements with proper radio frequency and direct current inputs. Demonstrating improvements in effective isotropically radiated power and in total radiated power compared to a single CMOS element, the hybrid integration approach proves effective in implementing coherent THz transmitter arrays. Theoretical and practical factors that reduce the radiated power compared with ideal arrays are also discussed.