OPERA™ Voice Quality Analysis -
Your Digital Ear.
OPERA™ Voice Quality Testing employs the latest international state-of-the-art standards like PESQ and PSQM. Intrusive testing based on natural voice signals ensures high accuracy, while it directly relates to the customer's perception of quality. OPTICOM's advanced algorithms and graphical analysis capabilities not only report the standardized result values, but a lot of views and details for problem analysis. The comprehensive algorithm set for voice quality testing includes:

> Voice Quality Measures
(optionally available for the software-only and all hardware configurations)
PESQ, the new industry standard for perceptual voice quality testing according to ITU-T rec. P.862 [2001], combines PSQM with PAMS, optimized for VoIP and hybrid end-to-end applications, MOS and MOS-LQ calculations

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click to [ enlarge picture ]

PSQM/IP, perceptual speech quality measure based on ITU-T rec. P.861 [1996] and PSQM+, incl. advanced delay compensation for end-to-end measurements, developed by OPTICOM
PSQM+, advanced perceptual speech quality measure according to ITU-T COM 12-20 [1998]
Echo measurement based on real voice signals, developed by OPTICOM, measures Echo Return Loss ERLpeak, ERL vs. delay

E-Model Transmission Rating Factor R according to ITU-T G.107, derived from PESQ [available with PESQ only]

> Competitive Strength for future Standards Due to OPERA's flexible design, user defined algorithms and advances in measurement standards can easily be provided as software plug-ins, ensuring OPTICOM's very competitive and short time-to-market.

> Common Features for Voice Quality Analysis
One way delay measurement, with PESQ also delay jitter vs. time and delay distribution
Measurement under double talk conditions
One way and two way measurements
Bulk call generation to stress the device/network under test
VAD analysis, Front-end clipping FEC, hold-over time HOT
and and dropout measurement (e.g. for packet loss analysis, burst error concealment) [available with PESQ only]
Background noise measurement
Signal-to-noise SNR measurement of speech and silent parts of a test signal

Multi-lingual voice reference stimuli available, incl. male and female speakers

> Telecom Applications and Features
True end-to-end voice quality testing of current and next generation networks, such as VoIP, VoDSL, VoATM, ISDN, GSM, POTS, based on real world voice signals
Analyze Speech Codecs, VAD behaviour, echo cancellers and signal enhancers with any voice signal
Include the acoustical path of handsets and mobile phones in the analysis using OPERA™ with an optional head and torso simulator (HATS) [OPERA software update available Q1/2003]
Monitor the QoS of any corporate, public or long distance network (surveillance)
Stress your network in order to observe the effects on the
transmission quality (bulk call generation)

> Specific Telecom Features
Plenty of detailed views and graphs provided for further fault analysis, incl. voice or wide band audio quality, time signals, spectra, echo, delay, jitter, VAD behaviour and call timing
Interactive or automated unattended measurements
Immediate overview of the QoS of your network based on standardized metrics
Remote control a single or numerous OPERA™ analyzers via an IP connection. Share a pool of OPERA™ systems in your test lab with other developers. Conveniently control the pool from your office PC
Freely combine various interface types in every measure-ment (e.g. VoIP calls from POTS to a VoIP terminal)

> Downloads

Download White Paper 'Voice Quality Testing' [as PDF / 1,9 MB]

-> Download OPERA Application notes [as PDF / 540 kb]

Download OPERA brochure [as PDF / 1,1 MB ]


Download OPERA data sheet [as PDF / 1,6 MB]

-> Download printable version of this page [as PDF / 77,1 kb]

> More details For more details on the technology of Voice Quality Testing refer to our Technology section