User's Manual Part 1

Nomad User’s Manual Chapter 5 – Defining a Test

 The system will make three attempts to contact the Audio Server. When connectivity is

verified, the level assist automation will begin.

Figure 5-18 - Auto-Level Assist Audio Server Connectivity Verification

 The auto-calibration process will run for several minutes displaying MOS progress as

volume is adjusted. Slightly different algorithms are used to determine optimal downlink

and uplink volume:

o The downlink algorithm closely follows Spirent’s recommendation for manual

volume adjustment (see Section 7.1.1.2). The algorithm increases the input level

until the Overdrive condition is detected. From there, the input level is decreased

for several cycles. The level producing the best MOS result from the ramp-down

procedure is stored.

o The uplink algorithm uses a form of binary search logic. The algorithm finds the

lowest output volume producing a valid uplink score. The volume is then adjusted

to the highest nominal operating level. The algorithm then uses combinations of

average level to zero in on the level producing the best MOS result.

Figure 5-19 - Auto-Level Assist Automation