13.5 MOS—PSQM, PAMS, AND PESQ MEASUREMENTS
Telephones on a gateway are connected on the FXS interface. This is similar to the PSTN central office interface provided to the user. Voice quality monitoring instruments are used for testing voice quality parameters such as MOS and other derived parameters. The popular measurement techniques for objective MOS quality are based on perceptual speech quality measure (PSQM), perceptual analysis measurement system (PAMS), and PESQ algorithms. PESQ is the latest in the family based on the P.862 series recommendations. Voice quality and PESQ are given in Chapter 20. The Malden Electronics Digital Speech Level Analyzer shown in Fig 13.2, which is popularly known as DSLAII, is a popular compact version of the equipment for measuring PESQ-based MOS quality as part of the MultiDSLA system.
The current active measurement is PESQ algorithm based. In the process of performing measurements, instruments provide several other parameters that help in identifying degradations. In general, there will be several common features among multiple instruments. The following list details some features of the MultiDSLA system. More features on this equipment are discussed at [www.malden.co.uk]:
Figure 13.2. Digital Speech Level Analyser-II for voice quality measurements. [Courtesy: (Picture of “Digital Speech Level Analyser (DSLAII) as part of MultiDSLA System” ...
Get VoIP Voice and Fax Signal Processing now with the O’Reilly learning platform.
O’Reilly members experience books, live events, courses curated by job role, and more from O’Reilly and nearly 200 top publishers.
