Discriminator aided phase lock acquisition for suppressed carrier signals

摘要: A discriminator aided technique for acquisition of phase lock to a suppressed carrier signal utilizes Costas loop which is initially operated open and control voltage its VCXO derived from detector that compares the reference frequency thus establishing coarse resolution with received signal. Then closed low-pass filter channel having bandwidth much greater (by factor about 10) than in I so effect results aid resolution. Finally, after acquisition, Q-channel switched substantially equal I-channel tracking.