Tait TB8100, Руководство пользователя

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8 Part A: Introduction
© Tait Electronics Limited December 2007
Power Saving
The TB8100 base station can save power by switching off parts of its circuitry.
The standard base station has a limited ability to reduce the current that the base
station uses, but the Power Saving Modes license lets you configure three
different power saving modes. This gives greatly increased flexibility and makes
it possible to get the power savings needed with a minimum sacrifice in quality
of service.
Note: Power saving only occurs when the base station is battery-
powered. It is not available if the PMU supplies more than one base
station.
Power saving
modes A base station with a Power Saving Modes license can operate in Normal,
Sleep, and Deep Sleep modes. These modes are enabled and configured in the
Service Kit.
The base station begins in Normal mode. If the base station is idle (receives no
valid signal ) for a defined length of time, it switches to Sleep mode, which saves
more power. If the base station is idle for a further defined length of time, it
switches to Deep Sleep mode, saving even more power. When it receives a
valid signal, it reverts to Normal mode.
Both receiver and transmitter contribute to the power saving.
The receiver is switched off, and then periodically switched back on. If it
detects a valid signal, it stays on, otherwise it is switched off again. The power
amplifier is always off when the base station is not transmitting. In power saving,
other parts of the transmitter circuitry are switched off as well. The longer the
Tx keyup time you select, the more circuitry is switched off.
Response times
The more power saved, the longer the response time. Initially, the radio user
needs to press PTT and wait before speaking, to give enough time for the
receiver to come back on and for the transmitter to key up.
Configuring
power saving You configure power saving when you define the channel profile that the base
station will use. For each mode, you specify Rx cycling (how long the receiver
stays switched off before it wakes up to check if there is a valid signal) and Tx
keyup (how long it takes for the transmitter to key up). In addition, you specify
how long the base station must be idle before it enters Sleep and Deep Sleep
modes. The exact amount of power saved varies, depending on the model of
base station and the pattern of traffic.