An adaptive delta modulator robust to transmission errors
Abstract
A technique is described suitable to make a fully digital adaptive delta modulator robust to channel error rates even higher than those of a satellite link. It is shown that the addition of a bias term into the adaptation algorithm makes the two step-sizes at the transmitter and at the receiver converge after a channel error. The step-size adapter parameters are obtained by a compromise between the convergence time and the idle-channel; in fact both are increasing funtions of the bias term. Results of simulations at 32 kbit/sec are given in terms of signal to noise ratio. The halving time of the relative deviation between the transmitter and receiver step-sizes is given as an index of the validity of the algorithm. Finally the error recovery time is defined and experimentally measured.
- Publication:
-
Space Communications
- Pub Date:
- March 1979
- Bibcode:
- 1979SpCom......283C
- Keywords:
-
- Adaptive Control;
- Algorithms;
- Delta Modulation;
- Error Correcting Devices;
- Analog To Digital Converters;
- Data Transmission;
- Signal To Noise Ratios;
- Communications and Radar