Many-to-many voice communications system testing for lab settings. Includes ITU P.862 Perceptual Evaluation of Speech Quality (PESQ) objective voice quality measurements.
ULTRA Voice™ is a many-terminal to many-terminal voice system tester ideal for evaluating complex wireless systems such as Project 25 (P25) land mobile radio and cellular push-to-talk (PTT). ULTRA Voice™ has the ability to control multiple radios and dispatch consoles simultaneously. A single terminal can talk to all other devices, or multiple talker-listener groups can be defined. The system is highly scalable, easily supporting hundreds of simultaneous calls. The system is controlled using a GUI-based test executive, allowing test scenarios to be developed, run, and saved for future use.
All calls are analyzed using the ITU P.862 Perceptual Evaluation of Speech Quality (PESQ) objective voice quality algorithm. The PESQ score can be mapped to a Mean Opinion Score (MOS) or, optionally, to a Delivered Audio Quality (DAQ) score.
Other analysis data available includes latency statistics (average, per frame, per utterance) as well as clipping statistics (front-end, tail-end, drop-outs).
Using the available control and analysis capabilities, many useful test scenarios can be generated and run including:
Simultaneous key of multiple radios (convert to callee)
Any simultaneous combination of the above using multiple talker-listener groups
(a "talker-listener group" is a single talker with one or more defined listeners)
By properly structuring the test sequence, the performance of a communications system can be evaluated under actual operating conditions and load. Anomalous system behavior is discovered and corrected in the lab, not the field. ULTRA Voice™ can detect and report (partial listing):
Failure to receive a channel (per talker)
Late entry into call (per listener)
Dropped call, drop-outs during a call (per listener)
Call performance before, during, after over-the-air-rekeying (OTAR) (per listener)
Voice quality (per listener)
Latency statistics (per listener)
Results of preemption due to simultaneous key, emergency, or priority (per listener)
Performance differences due to encryption, modulation, or system topology (per listener)
Impact of gateways and transcoders on voice quality and latency (per listener)