A MODE-AVERAGING DIVERSITY COMBINER

Abstract

A diversity-combining technique is described which reduces frequency distortion caused by multipath propgation in high-frequency, single- or double- sideband, voice, radio transmission. By repetitively sweeping a null through the vertical polar pattern of the receiving antenna, the relative amplitude of signal components arriving by the various propagation modes is varied at a rate which is high compared with the highest audio modulating frequency. A running average of the time-varying resultant of the various mode voltages is diode rectified to extract the audio intelligence. Mode-interference-caused transmission nulls at particular frequencies in the radio spectrum are filled in by this averaging process. The technique requires no more equipment than conventinnal combining and would appear to offer superior performance.

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Document Details

Document Type
Technical Report
Publication Date
Dec 01, 1963
Accession Number
AD0425997

Entities

People

  • O. G. Villard Jr.

Organizations

  • Stanford University

Tags

Communities of Interest

  • Advanced Electronics
  • Air Platforms
  • Energy and Power Technologies
  • Weapons Technologies

DTIC Thesaurus Topics

  • Amplitude
  • Amplitude Modulation
  • Audio Frequency
  • Bandwidth
  • Detectors
  • Distortion
  • Electronics
  • Frequency
  • Military Research
  • Modulation
  • Modulators
  • Oscillators
  • Radio Frequency
  • Radio Transmission
  • Steady State
  • Transmitters
  • Waveforms

Readers

  • Phased Array Antenna Design.
  • Radio communications and signal processing.