Frequency-Selective Limiters Using Nonlinear Bandstop Filters

• Published in: IEEE transactions on microwave theory and techniques Vol. 57; no. 1; pp. 157 - 164
• Main Authors: Phudpong, P., Hunter, I.C.
• Format: Journal Article
• Language: English
• Published: New York, NY IEEE 01.01.2009; Institute of Electrical and Electronics Engineers; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Applied sciences; Bandstop filters; Bandwidth; Channels; Circuit properties; Circuits; Constraining; Devices; Diodes; Dynamic range; Electric, optical and optoelectronic circuits; Electronic circuits; Electronics; Exact sciences and technology; Frequency filters; Insertion loss; limiting; microstrip resonators; Microwave circuits, microwave integrated circuits, microwave transmission lines, submillimeter wave circuits; Microwave devices; microwave limiters; nonlinear filters; Nonlinearity; Oscillators, resonators, synthetizers; Radio frequencies; Radio frequency; Resonator filters; Signal processing; Switching; Wideband; Prototype; High Q factor; Third order; Non linear filter; microwave limiters; Lossy medium; Microstrip resonator; nonlinear filters; limiting; Frequency selector; Switching; Mode filter; High power; Frequency selection; Wide band; Reflection mode; Bandstop filters; Microwave limiter; Insertion loss; Band stop filter; Low-power electronics; Multiple channel; microstrip resonators; Cascade connection
• ISSN: 0018-9480; 1557-9670
• DOI: 10.1109/TMTT.2008.2009078

This paper presents a novel design for frequency-selective limiters based on reflection-mode nonlinear bandstop filters. This technique enables the use of low- Q lossy resonators for high- Q bandstop filter applications. Frequency-selective limiters described here achieve fast switching, high levels of power limiting, and flexible channel bandwidth. The prototype for a third-order device indicates 2-dB insertion loss for low RF powers. At high RF powers, it demonstrates 18-dB limiting level, 3-dBm limiting threshold, and 300-MHz limiting bandwidth. The switching speed is less than 10 ns, thus the spike leakage is minimized. The single-channel limiters are cascaded to provide limiting in wideband channels. The multichannel device is able to compress the dynamic range of the signals over 30 dB.