Download or read book Required Signal-to-noise Ratios for HF Communication Systems written by Hiroshi Akima and published by . This book was released on 1969 with total page 68 pages. Available in PDF, EPUB and Kindle. Book excerpt: Values of required signal-to-noise ratios are estimated for the following HF communication systems: amplitude-modulation (AM) voice communications systems, noncoherent frequency-shift-keying (NCFSK) radioteletypewriter systems, composite voice and teletypewriter systems, aural-reception radiotelegraphy, and phototelegraphy (facsimile). Except for NCFSK systems, for which certain aspects of the basic performance had to be evaluated in the course of this study, values of required signal-to-noise ratios are estimated from published data in the open literature.