The synchronization techniques are applicable to both narrowband, multiple frequency shift keyed (MFSK) digital transmission systems and wideband frequency hopping systems. The techniques do not require specific synchronization overheads to be incorporated into the transmissions, but operate using the normal traffic signal formats. It is required that digital signal processing be employed at the receiver for the procedures to be effective. Three distinct synchronization methods are discussed: modulation-derived synchronization; code-derived synchronization; and combined modulation- and code-derived synchronization.