Voice Quality Testing Across TDM Networks

Overview

Voice quality is essential for all Networks as well as Gateways and Switches. Providing the mechanism for VQT over T1/E1 trunks is essential. The VQuad™ with TDM option provides the ability to perform manual or automated tests on the T1/E1 networks. The GL VQuad™ software combined with GL's Voice Quality Testing (VQT) software permits this desired VQT testing, yielding results that include PESQ (LQ/LQO/WB)/PAMS/PSQM+ Mean Opinion Scores (MOS). These results provide an excellent overall measure of voice quality of the equipment under test.

The VQuad™ with TDM option includes the HD Universal Dual T1/E1 Card or tProbe™ T1 E1 Base Unit or Portable USB T1 E1 Analyzer for a truly portable solution. Using T1/E1 Analyzer VQuad™ can generate and receive up to 8 simultaneous CAS, PRI ISDN, or No Call Control (NOCC) calls on either T1 or E1 trunks. The T1/E1 option includes a script based CAS State Machine for creating any desired CAS protocol. Included with the PRI ISDN are all variants associated with ANSI and ETSI specifications.

		VQuad™ User's Guide

		VQT User's Guide

		VQT WebViewer™ User's Guide

		tProbe Brochure

		Complete VQT Brochure

		View Presentation

The GL’s VQT utilizes three widely accepted algorithms to perform the voice comparisons, the Perceptual Evaluation of Speech Quality (PESQ LQ/LQO/WB’) per Rec. P.862.1/P862.2, the Perceptual Analysis / Measurement System (PAMS) per Rec. P.800, and the Perceptual Speech Quality Measurement (PSQM) per Rec. P.861. PESQ provides an objective measurement of subjective listening tests on telephony systems. PAMS predicts overall subjective listening quality (a human's perception of quality) without requiring actual subjective testing (a very expensive and time-consuming process). PSQM predicts subjective quality of speech codecs without requiring subjective testing. The VQT performs PESQ, PAMS, and PSQM (+) simultaneously, using two voice files (Reference File and Degraded File) and provides the algorithm results along with analytical results in both a graphical and tabular format.

Additional Information

Main Features

Connect at endpoint of a TDM network
Supports up to 8 simultaneous T1/E1 channels using VQuad™ interface Automatic call control (CAS, PRI ISDN, or No Call Control (NOCC)
Automatic call control (CAS, PRI ISDN, or No Call Control (NOCC)
Automatic send/receive of voice files over already established calls
Time/Digit/Tone triggering of send/receive voice files.
Compact and portable solution for testing end-to-end voice quality
Synchronized software for sending/recording of voice files at multiple locations
Flexible architecture and features for recording locations, parameters, and time
GL VQT Automatic Mode allows automatic execution of the VQT algorithms (PESQ, LQ/LQO/WB).
Additional measurements include Clipping, Jitter, Latency, Noise and Signal Levels.
Results available in real-time or post-processing
Fax Testing for T1/E1 interface is coming soon

Screenshots

Buyer's Guide:

Item No.	VQuad™ Network Options
VQT010	VQuad™ Software (Stand Alone)
VQT013	VQuad™ with SIP (VoIP) Call Control
VQT015	VQuad™ with T1 E1 Call Control
Item No.	VQuad™ Miscellaneous
VQT204 VQT204u VQT204e	GPS for Dual UTA
VQT270	VQuad™ Probe with Dual UTA
VQT030	Network Command Center (Multi-Node Command and Control Center for VQuad™ Systems)
VQT241	Dual Universal Telephony Adapter (UTA) with RTD, and OWD
PTE001	tProbe™ Dual T1 E1 Laptop Analyzer with Basic Analyzer Software
HTE001	Universal T1/E1 Card with Basic Analyzer Software
UTE001	Portable USB based Dual T1 or E1 Laptop Analyzer with Basic Analyzer Software
Item No.	VQT
VQT002	Voice Quality Testing (PESQ only)
VQT004	Voice Quality Testing (PAMS, PSQM, PESQ)
VBA032	Near Real-time Voice-band Analyzer
EMU037	Echo Measurement Utility (EMU) Software

* Specifications are subject to change without notice.