60-70 dB isolation 2-19 GHz MMIC switches

Millimeter-wave MMIC single-pole-double-throw passive HEMT switches using impedance-transformation networks

“…Monolithic p-i-n diode switches have demonstrated good performance even up to MMW frequency [1]. However, since the p-i-n diode process is not compatible with the high electron-mobility transistor (HEMT) monolithic-microwave integrated-circuit (MMIC) process, passive HEMT (or FET) switches are still very popular [2]- [12]. The reason is that they can be integrated with the other major building blocks in a MMW transmit/receive (T/R) module, which are mostly fabricated using the HEMT MMIC process.…”

“…The reason is that they can be integrated with the other major building blocks in a MMW transmit/receive (T/R) module, which are mostly fabricated using the HEMT MMIC process. For frequencies of 20 GHz or lower, series and/or shunt configurations of a passive FET can readily serve as very good switches with excellent isolation and insertion-loss results demonstrated in [2] and [3]. However, at higher frequencies, the parasitic capacitance (mainly the drain-to-source capacitance ) will degrade the isolation performance significantly.…”

A high‐isolation switch based on a standard GaAs process

“…In addition to that, the symmetric shunt transistors technique [10] has been realized. This technique refers to transistors Q 1 .…”

“…Furthermore, because of the rapid development in both WLAN and WiMAX wireless communications, the technique of incorporating the WiMAX operating band with the WLAN operating band to create a multiband slot antenna specifically designed for these applications are presently the most widely discussed topics [10,11]. However, to achieve sufficient impedance bandwidth, complicating solution such as the fractal slot antenna design [10] or compelled to insert parasitic elements to the radiating element [11] are proposed.…”