Radio frequency arraying method for receivers
Abstract
A method and apparatus for increasing the signal to noise ratio of a receiving facility for coherent frequency reception by arraying receiving systems using separate antennas for each, or one antenna for all systems are presented. One system is operated with a carrier tracking loop to provide a first local oscillator frequency for the first and all other systems arrayed, with individual tracking loops in all other systems operated at IF for tracking out any phase differences due to separate group delays using an adjustable phase shifter for a second reference to compensate for different group delays in the antenna and low noise amplifier of each of the other systems. The second IF output of all systems is summed into the first system. This technique may also be used when two systems are arrayed to an antenna designed for circular or linear polarization diversity reception to effectively provide the same signal to noise ratio for both polarized signal transmission channels that would result from matched polarization. An arrangement adapted to high rate telemetry reception is disclosed. With additional components, the same arrangement is adapted to provide low rate telemetry reception as well.
- Publication:
-
National Aeronautics and Space Administration Report
- Pub Date:
- January 1980
- Bibcode:
- 1980nasa.reptT....B
- Keywords:
-
- Arrays;
- Radio Frequencies;
- Radio Receivers;
- Frequency Scanning;
- Patents;
- Radio Reception;
- Signal To Noise Ratios;
- Telemetry;
- Communications and Radar