Patent · US Expired

Low noise microstrip voltage controlled oscillator

US4310809A · kind A · utility

37Cited by
4References
8Claims
0Family size

Assignee

Inventors

Key dates

Filing dateApr 27, 1979
Grant dateJan 12, 1982
Priority date
Expiry dateApr 27, 1999

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH03B2201/0208
  • WIPO fieldBasic communication processes
  • WIPO sectorElectrical engineering

Abstract

The invention comprises a microwave oscillator using a stripline circuit. The active device utilized in the oscillator is a bipolar transistor. A microstrip circuit is coupled to the emitter of the transistor while the collector is coupled to ground. This generates a negative impedance characteristic at the base of the transistor at the operating frequency. The operating frequency is determined by a varactor which is series tuned with an inductor. The impedance of the series tuned circuit is transformed to match the input impedance of the transistor by a microstrip circuit. Microstrip isolation circuits are utilized to couple appropriate bias signals to the emitter and the base to establish the proper operating point for the bipolar transistor. The output signal is taken from the base circuit of the transistor through the series combination of two microstrip circuits and a capacitor. A second varactor is loosely coupled to the base circuit of the transistor to provide for fine tuning. The frequency control characteristic of the oscillator can be made linear by utilizing a hyper abrupt varactor.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.