Adaptive digital tanlock loop with no delay

This paper proposes an adaptive technique for rapid error correction of a digital tanlock loop architecture with no time delay (ANDTL) unit and with a linearized phase-detector. The ANDTL uses a feed-forward technique for early comparison between the estimated value of the input signal frequency and that of the DCO (digital controlled oscillator). The error signal resulting from the comparison is used to set the initialization of the DCO in order to match that of the incoming signal. The performance of the ANDTL architecture was evaluated by using FSK demodulation and results indicate a marked improvement in the loop acquisition time as well as its jitter in the presence of noise.