Correlation Bandwidth Measurements over Troposcatter Paths

The objective of this program is to obtain data necessary for the design of troposcatter modems for use in future MALLARD troposcatter systems. In support of this objective, propagation data are being collected over three types of troposcatter paths to empirically determine cross correlation versus frequency spacing and other fade statistics to provide a basis for the determination of the maximum bit rates that can be satisfactorily transmitted by frequency diversity methods with a stated error probability under known conditions of path length, path terrain, season, antenna size and beamwidth, radio frequency band, occupied bandwidth, radiated power, and frequency spacing. These data are also directly applicable to the prediction of space diversity maximum bit rates at stated error probabilities since the correlation bandwidth and fade statistics directly affect the error probabilities and bit rates obtainable. The propagation data are being collected through the use of a fixed C- and X-band transmitting system located at the RADC troposcatter test site at Model City, New York. The receiving instrumentation is located in a special van that is moved to various locations to provide variations in terrain.