MICROWAVE OPTICAL RECEIVER TECHNIQUES.
Abstract:
The report presents the results of the second quarter of effort on a one-year applied research program on the use of various techniques for microwave optical communications through the atmosphere. The relative theoretical advantages of direct and heterodyne optical receivers are considered further, and some popular misconceptions about the nature of background noise are pointed out. Further consideration is also given to modulation and information processing techniques and to the use of multimode lasers in microwave-bandwidth systems. Specific systems are recommended which incorporate present techniques in an optimum manner. A comprehensive experimental program of direct-detection microwave-optical communications over an outdoor path has shown that the multiplier phototubes developed in this laboratory can achieve excellent results with minimum operating difficulty. Author