NTSC and MAC Television Signals in Noise and Interference Environments

The quality of video signals delivered by future DBS systems will be governed by two main limiting factors: noise and interference. The results of a measurement program giving the susceptibility of the FM-NTSC television signal to noise and interference are reported. These results were obtained from the subjective assessment of the picture quality by a large number of viewers. Different types of viewers were used and the results were analyzed accordingly. A modelling of these results was performed using the logistic function. The noise results were compared to the previous TASO results to find the evolution in required television picture quality. The results of the interference tests were used to set the technical characteristics used for planning of DBS at the RARC-83. — A second phase in the measurement program was the comparative evaluation of the conventional NTSC coding and the MAC (Multiplexed Analogue Components) video coding system. This new coding system is gaining importance worldwide: it is proposed by the EBU as the standard format for DBS in Europe for 625-line television standards, and in North America work is being carried out to devise a 525-line MAC coding system to be used for DBS. This paper presents the preliminary results of a comparison study on the susceptibility of the MAC signal as compared to the susceptibility of the conventional NTSC signal to system noise as a function of over-deviation, co-channel interference and adjacent channel interference. This study was done using the baseline system parameters used at the RARC-83.

Print ISSN

0036-1682

Published

1984-01

Content type

Original Research

DOI

10.5594/J16823