Reducing technique of sidelobe in millimeter wave beam multiplexing system

In the millimeter wave beam multiplexing system, sidelobe decreases data-rate because data-rate is decided by signal to noise level (SINR), and sidelobe decides SINR. Sidelobe is decided by interference of coupling and phase error between RF channels, so suppress coupling and phase error is important to obtain high data-rate. Structures, such as cavity that silicon chip is placed in it to reduce length of bond-wire, grounded coplanar wave guide (CPWG), and higher positional accuracy of via, can obtain lower coupling and phase error. This paper describes effect of those structures to reduce coupling, and phase error example of manufactured RF board including beamforming antenna and silicon chips.