Title :
Tunable active bandpass filters using three-terminal MESFET varactors
Author :
Lin, J. ; Itoh, T.
Author_Institution :
Dept. of Electr. Eng., California Univ., Los Angeles, CA, USA
Abstract :
The concept of three-terminal MESFET varactors is presented. Based on this concept, two types of tunable active bandpass filters working at the X-band were developed. The first circuit used two MESFETs, of which one was used as a MESFET varactor and the other was used to generate a negative resistance. The second circuit used only one MESFET, which had both the functions of the two MESFETs in the first circuit. The experimental results showed the possibility of using the MESFET in the active mode to generate both a negative resistance and a variable reactance.<>
Keywords :
Schottky gate field effect transistors; active filters; band-pass filters; field effect transistor circuits; microwave filters; negative resistance; solid-state microwave circuits; tuning; varactors; X-band; active mode; negative resistance; three-terminal MESFET varactors; tunable active bandpass filters; variable reactance; Band pass filters; Capacitance; Filtering theory; Frequency; MESFET circuits; Optical variables control; Passband; Tunable circuits and devices; Varactors; Voltage;
Conference_Titel :
Microwave Symposium Digest, 1992., IEEE MTT-S International
Conference_Location :
Albuquerque, NM, USA
Print_ISBN :
0-7803-0611-2
DOI :
10.1109/MWSYM.1992.188139
