Spectrum Engineering

After a brief description of the significance of the radio refractive index and its variation in the lower troposphere, a catalog of fading mechanisms is presented. Attention is directed to the supporting refractive index structure, the characteristics of the fading signal, and the available remedies. The phenomena of multipath fading are described, and the theoretical amplitude distributions are presented. Diversity reception (frequency or space) is outlined for reducing the fading due to multipath. Specific expressions are given for determining the frequency or space separations. Successful remedies for microwave fading that are keyed to specific fading mechanisms also constitute a means of measuring the characteristics of the prevailing meteorological conditions. Specific expressions are given to accomplish this for the multipath and diffraction fading mechanisms.

This is the second part of a four-part report containing tabulations and graphs of transmission loss data resulting from propagation experiments in the 230 to 9200 MHz frequency range conducted over irregular terrain in Colorado. This part describes data obtained at a single common receiver site at Fritz Peak, Colorado, over propagation paths varying in length from 3.0 to 120 km.

This is the third part of a four-part report containing tabulations and graphs of transmission loss data resulting from propagation experiments in the 230- to 9200- MHz frequency range conducted over irregular terrain in Colorado. This part describes data obtained at a common receiver site, which is located on a high mesa near Golden, Colorado, over propagation paths varying in length from 0.5 to 80 km.