January 1971 | NTIA Technical Memo OT ITS TM 27
Radio Channel Characterization
Roger K. Salaman; Gene G. Ax; Arthur C. Stewart
Abstract: The critically increasing demand for radio frequency allocations has stimulated development of information needed to reexamine efficient use of the radio spectrum. The characteristics and limitations, of the radio channel, with emphasis on the transmission channel (propagation and noise), are discussed along with typical communication systems currently using the radio spectrum.
Additional studies required before spectrum use can be comprehensively reviewed include (1) detailed specification of the information requirements (present and future), (2) a comprehensive computer program to allow analysis[,] and trade-off studies throughout the spectrum, based on the unit programs uncovered in this study, (3) techniques for predicting manmade noise and interference and their effects on system performance, and (4) extension of propagation models to account for (a) the effects of vegetation and manmade structures, and (b) short-term propagation variations that affect modem performance.
Keywords: propagation; noise; frequency allocation
Disclaimer: Certain commercial equipment, components, and software may be identified in this report to specify adequately the technical aspects of the reported results. In no case does such identification imply recommendation or endorsement by the National Telecommunications and Information Administration, nor does it imply that the equipment or software identified is necessarily the best available for the particular application or uses.