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(POLQA v3, POLQA v2.4, PESQ)
GL's Voice Quality Testing (VQT) software supports the next-generation voice quality testing standard for fixed, mobile and IP-based networks using POLQA ver 2.4 and optional upgrade ver 3 (ITU-T P.863), PESQ (ITU-T P.862), PESQ LQ / LQO (P.862.1), PESQ WB (P.862.2). VQT analyzes the degraded (received) files and compares them with the reference (sent) files using ITU standard algorithms PESQ LQ/LQO/WB, and POLQA (NB, WB, SWB).
PESQ provides an objective measurement of subjective listening tests on telephony systems. POLQA, Perceptual Objective Listening Quality Analysis, is the successor of PESQ (ITU-T P.862) analysis and the next generation voice quality testing standard for fixed, mobile and IP-based networks.
POLQA® is a registered trademark of OPTICOM. GL is one of the Test & Measurement manufacturers that has adopted POLQA/P.863 in its Voice Quality Test solution, by obtaining the essential rights to use POLQA® standard, and hereby acknowledge that the images or text references to POLQA used in this document originally copyrights with Opticom.
The VQT application is available with the following options:
VQT works in conjunction with VQuad™ or VQuad™ Probe HD to provide "end-to-end assessment" with additional test and measuring capabilities. VQuad™ scripting allows for automated call control, and traffic simulation to conduct tests on Wireless, IP, PSTN and TDM networks. The captured data are analyzed in VQT and the results of the VQT algorithms, POLQA and PESQ LQ/LQO/WB, are displayed both in tabular format as well as graphically. Additional analytical results are displayed as part of the assessment such as POLQA MOS, E-Model, Signal Level, SNR, jitter, clipping, noise level, and delay (end to end as well as per speech utterance). All results are saved to file and database for post processing viewing along with sophisticated searching on the results within the VQT application and using the WebViewer™ (remote and local access).
VQT POLQA Measurements and Analysis
The GL Voice Quality Testing (VQT) product utilizes several industry standard ITU algorithms in order to measure the speech quality of a transmitted voice file. VQT compares the original unprocessed signal with the degraded version using POLQA (ITU-T P.863) and PESQ (ITU-T P.862+P.862.1) international standard voice quality test methods. The GL VQT can either be installed or operated on a stand-alone system or reside as an optional feature, on other GL products. GL's VQuad™ also supports the POLQA (ITU-T P.863) standard for voice quality analysis
|Adopted in 2011, ITU-T P.863||Adopted in 2001, ITU-T P.862|
|Suitable for 3G and 4G networks, VoIP networks and NGN networks delivering HD- quality voice services such as "wideband" and "super-wideband" telephone calls, 7 kHz and 14 kHz frequency range.||Suitable for G.711 A law and u law, and low bandwidth 300 to 3400 Hz voice bandwidth. Also supports WB (7kHz frequency range) using PESQ ITU-T P.862.2.|
|POLQA works quickly and accurately. POLQA is superior to existing standards, and has overcome all known issues and limitations of PESQ||
PESQ-based measurements will still be considered an industry standard for several years, also for reasons of backward compatibility