Installation guide

TD 92408EN

9 December 2011 / Ver. G

System Planning

Ascom VoWiFi System

2.5 Battery Considerations

2.5.1 Speech Time and Standby Time

Both the speech time and the standby time is greatly affected by the configuration of the

network and th

e power save mode used.

The standby time can be increased several times by following the instruc

tions in chapter

10.4 Beacon Period on pa

ge 30 and 10.5 DTIM Interval on page 30.

During a call, the power savings are significant with the VoWiFi Ha

ndset in U-APSD mode

compared to Active mode. For VoWiFi Handset details, see Data Sheet, Ascom i62 VoWiFi

Handset, TD 92587EN. Note that given times are approximate since there are num

erous of

variables that affect both the speech and standby time. If the network supports U-APSD,

is strongly recommended to use it.

Note: If U-APSD is uns

upported by the infrastructure, the VoWiFi Handsets will use Active

mode even if they are configured to use U-APSD.

If U-APSD is unsupported by the infrastructure, cons

ider the following regarding PS-Poll and

Active mode: PS-Poll mode consumes less power than Active mode and thereby extends the

speech time. However, PS-Poll mode is designed for low-density residential installations

with a single user per AP and cannot meet high speech quality requirements. Therefore, PS-

Poll mode is not recommended for use when high speech quality is required; in this case,

Active mode is a better choice.

2.5.2 Battery Lifetime

Since the number of charging cycles need

ed are dependen

t on the power consumption, the

lifetime of the battery is highly dependent of the settings used. A poor network setup with

no power save functionality will decrease the lifetime dramatically.

For VoWiFi Handset times, see Data Sheet, Ascom i62 VoWiFi Handset, TD 92587EN.