Phase-Shift Radio Teletype

A method whereby teletype transmission is accomplished by phase-shift rather than frequency-shift keying a carrier signal is outlined. Reception methods involving coherent or synchronous detectors are presented. Results indicate that the synchronous system offers an ultimate gain of 12.5 db over FSK with 10.5 db advantage realizable in the practical case. The practical synchronous system also shows an advantage of about 2.5 db over the Predicted Wave Radio Teletype System described by Doelz and Heald.