Single-Oscillator Wideband VCO.

Abstract

The effort on this program was aimed at fabricating a low-voltage, high-speed VCO to cover the 11- to 18-GHz frequency range for use in a set-on VCO-type of frequency memory in place of an arrangement requiring three VCOs and a multiplexer. The most important accomplishments were: (1) The development of a low-power VCO covering the 11- to 18-GHz range using a GaAs hyperabrupt junction varactor diode and requiring a very small tuning voltage requirement; (2) The fabrication of a new type of frequency discriminator which uses the roll-off characteristic of a microwave FET; (3) Measurements leading to an understanding of the behavior of GaAs hyperabrupt varactors at high input levels. GaAs hyperabrupt varactors were produced having capacitance ratios in excess of 10:1, but less than the expected frequency tuning ranges were orginally obtained from VCOs with these hyperabrupt varactors used as the tuning diode. Special network analyzer measurements with varying levels of input drive power showed the impedance of the hyperabrupt varactors to be unusually sensitive to the incident power level resulting in a significant reduction in maximum capacitant at levels consistent with those to which the varactors are exposed in the oscillator.

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Document Details

Document Type
Technical Report
Publication Date
Apr 01, 1978
Accession Number
ADA075200

Entities

People

  • D. D. Mawhinney

Organizations

  • Sarnoff Corporation

Tags

Communities of Interest

  • Advanced Electronics

DTIC Thesaurus Topics

  • Amplifiers
  • Analyzers
  • Bandwidth
  • Bipolar Junction Transistors
  • Broadband
  • Capacitance
  • Classification
  • Detectors
  • Diodes
  • Electronics Laboratories
  • Frequency Bands
  • Impedance
  • Measurement
  • Oscillators
  • Power Levels
  • Semiconductors
  • Varactor Diodes

Readers

  • Electronics Engineering