Implementing RF signal limiter with heterojunction devices

Microwave limiters are used to prevent burnout and permanent damage in power sensitive components such as receivers and mixers. State-of-the-art limiters are implemented employing PIN diodes, in which limiting is provided by varying the RF resistance of the diode. The PIN diode is a cheap and easy-to-use devices but its bandwidth and power rating is limited. Furthermore, PIN diodes cannot readily be fabricated. in MMIC technology. Here, an investigation is presented on the feasibility of employing heterojunction devices in limiters. This paper presents a T-switch attenuator formed by HEMTs simulated at X-band.