MCM low-cost true time delay phase shifter

This paper presents a novel 3D integration approach for a low-cost 3-bit true time delay (TTD) phase shifter for 11.5 - 13GHz communication phased-array antenna. The module is realized with surface-mountable PIN diodes and introduces signal delay from 1 to 7λ at the center frequency of the work-band, which represent delay from 80 to 560 ps with increment 80 ps. The proposed phase shifter implements on-board TTL compatible digital drivers. The solution is based on a MCM approach, realized using standard MCM-D, MCM-L or PCB technology. The substrate material is either 98% alumina ceramic (Al203), or Rogers TMM10i, both materials having similar RF properties, allowing to transfer the design between the different technologies without further fine-tuning of the layout. The high-frequency board-to-board transitions utilize BGA technology, making the module compatible with the existing SMT assembly process. The module occupied aria is 50x25mm.