Broadcast Engineer's Reference Book

Paul Dubery

7.4B Digital RF Measurements

 

 

In the days of analogue-only services, the apology caption was usually a confirmation of picture degradation that had already become obvious to the viewer. As the picture became more noisy, it would still be viewable up to relatively high S/N levels. Automatic monitoring of the analogue video signal parameters at strategic points throughout the distribution and transmission path has become a recognised way of predicting network degradation, and many broadcasters have come to rely on such systems.

In the digital broadcasting world, the need for network monitoring becomes even more important and the earliest DTT implementations have incorporated varying levels of monitoring sophistication. The industry ...