Non-Sampling UHF Same Frequency Repeater.

Abstract

The UHF Same Frequency Repeater suffered from low usable isolation because of the limitations in manually tuning the matching network of a hybrid to equal the constantly varying impedance of an antenna. Operation of the repeater was further hampered by the adjustments necessary to accommodate band switching. An Automatic Impedance Matching (AIM) network was developed to continuously adjust the impedance of the matching network to automatically maintain a high isolation between the transmitter and receiver ports of the hybrid. A common RF switch was also designed as part of this program so that channel switching could be accomplished with only one control, without the need to make readjustments. RFI due to incomplete transmitter shutdown was eliminated by the addition of a coaxial relay. Other sources of RFI were eliminated by replacing most RF cables with double-shielded coax.

Document Details

Document Type
Technical Report
Publication Date
Mar 01, 1972
Accession Number
AD0903919

Entities

People

  • Robert F. Hertz

Organizations

  • Eaton Corporation

Tags

Communities of Interest

  • Advanced Electronics

DTIC Thesaurus Topics

  • Automatic
  • Frequency
  • Frequency Bands
  • Impedance
  • Mechanisms (Engineering)
  • Radio Frequency Cables
  • Repeaters
  • Sampling
  • Switches
  • Switching
  • Transmitters

Readers

  • Electronics Engineering
  • Radio communications and signal processing.
  • Systems Analysis and Design