User's Manual Part 2
Nomad User’s Manual Chapter 9 – Voice Quality Configuration Options
Copyright © Spirent Communications, Inc. 2013 120
9.5 Remote Unit Testing
Nomad provides the option for Remote Unit testing. In this configuration, a handset connected to
the local Spirent ME hardware unit sources audio to and receives audio from a handset connected
to a second hardware unit. In many cases, the second hardware unit is located remotely (i.e. in
another office or city). One handset will source speech while the other will record speech for ten
seconds. The process will alternate in the next ten second cycle.
To perform Remote Unit hardware testing:
Connect one handset to Channel 1(ME), NB1 (ME HD) or HD1 (ME HD) on the local Spirent
ME or HD ME hardware unit.
Connect the second to Channel 1(ME), NB1 (ME HD) or HD1 (ME HD) on the second
Spirent ME or HD ME hardware unit.
If the second hardware unit is located remotely, ask a colleague for assistance in setting up
that unit.
Figure 9-5 - Remote Unit Hardware Configuration for a Spirent ME unit
In the local Nomad software, configure Channel 1 as a Mobile task with the following
setting:
o Session → Uplink Device: Base task on remote unit
In the remotely located Nomad software, configure Channel 1 as a Base task with the
following setting:
o Session → Downlink Device: Mobile task on remote unit
Confirm that both test channels use the same Scoring Model. Both channels must be set for
either PESQ or POLQA in the Session dialog.
If testing is performed using Spirent HD ME hardware, make sure the proper Audio
interface (High definition or Narrowband) is selected.
Place a call from Handset 1 to Handset 2. The incoming call must be manually answered.
Start a new test.
The test sequence starts with the local handset sourcing data to the remote handset. Data
collected at the remote handset will be displayed in Channel 1 of the remote Nomad
installation.
In the next cycle, the remote handset will source data to the local handset. Data collected at
the local handset will be displayed in Channel 1 of the local Nomad installation.
During testing, adjust volume using the Settings → Levels dialog such that the Ins Gain
(PESQ) or Attenuation (POLQA) reading for each channel falls as close to 0 as possible. The
Input and Output sliders should sit within the Normal Operating Range values displayed.