User's Manual Part 2

Nomad User’s Manual Chapter 9 – Voice Quality Configuration Options

9.2 Audio Server Testing

Spirent Communications provides access to a centralized call server that sources downlink data and

records uplink data in the audio server testing configuration. The mobile handset will source

speech while the audio server will record and score the uplink speech sample for ten seconds. In

the next ten second cycle, the audio server will source speech while the mobile handset records and

scores the downlink speech sample.

To perform Audio Server testing:

 Connect the test handset to any active channel on the Spirent ME hardware unit via audio

cable or Bluetooth.

 On the Nomad Test Setup screen, configure that channel as a Mobile task with the

following settings:

o Session → Uplink Device: Audio Server

o Channel Settings → Audio interface for this channel: Analog Interface(ME),

Narrowband (ME HD), High Definition (ME HD) or Bluetooth Interface as desired.

Note that a maximum of two Bluetooth devices is permitted for Voice Quality testing

at one time.

 If the test mobile is connected via analog audio cable, volume settings may be optimized

using Auto-Level Assist.

 Click the Start Logging Session button and proceed through the Start Logging Session

Wizard.

 At the conclusion of the Start Logging Session Wizard, Nomad will automatically place test

calls for devices which are connected via Bluetooth and which have been configured for

auto-dial on the Settings → Voice Quality tab. All other calls must be manually placed to

the Audio Server.

 The test sequence starts with the mobile handset sourcing data to the Audio Server.

 In the second half of the cycle, the Audio Server will source data to the mobile handset.

Downlink data collected at the handset is displayed in the Voice Quality Task Status

Window during the following cycle.

Figure 9-2 - Voice Quality Task Status Window

 During testing, adjust the downlink volume using the Settings → Levels dialog such that the

Insertion Gain (PESQ) or Attenuation (POLQA) falls as close to 0 as possible. The Input

slider should sit within the Normal Operating Range values displayed.

 End the test when desired.

Test results can be found on the Voice Quality Summary tab of the output report.