Wavenet Technology Pty Ltd. BM3800D User Manual

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Installation________________________________________________ Boomer-III User Manual & Integrator’s Guide 
 
Copyright Wavenet Technology © October 2003 
46 
BM310012WT04 
Power Save Protocol 
The modem typically uses current provided by the host/terminal 
battery. For the product to be usable for a reasonable period in portable 
applications, the host/terminal battery power must be conserved. To 
meet this requirement, the modem uses DataTAC Power Save protocol. 
The Power Save Protocol defines the following four modem power 
consumption states: 
Off 
The modem is turned off or the host/terminal (battery) 
has failed. 
Sleep 
The processor is sleeping and wakes up to an interrupt, 
but the RF section is off. 
Receive 
The processor is actively processing information; the RF 
sections are on and demodulating data. 
Transmit 
The processor is actively processing information; the RF 
sections are on and transmitting data. 
Power Profile 
The modem’s power consumption profile depends on the usage and the 
network configuration of the Power Save protocol. 
For example, the following numbers present a typical profile for the 
Boomer-III modem based on reasonably heavy usage and assuming a 
3.8V supply current: (Power Save Mode = Maximum) 
 
80 % Sleep @ 4.4 mA typical 
 
19.9 % Receive @ 76 mA typical 
 
0.1% Transmit @ 1.6A typical 
The actual percentage of total time spent in each state (transmit, 
receive, sleep) is a function of the following variables. 
Network configuration  
On networks supporting Power Save operation, the network 
configuration impacts how long the modem must be in the sleep state. 
NoteNeither Wavenet nor any developer has any direct control over 
the network configuration. Networks supporting Power Save are 
typically configured to preserve the battery life of modems of their 
subscriber base.
 
Message traffic model  
The message traffic model defines how many messages are transmitted 
and received, and the average length of the messages sent and received 
in a given working day. For instance, a dispatch application could have 
a message traffic model as follows: 
 
Messages transmitted in 8 hour day: 25 
 
Average length of transmission: 120 bytes 
 
Messages received in 8 hour day: 10