Product Description

Nokia MetroSite EDGE Base Station features
DN991444 © Nokia Corporation Draft 29 (98)
Issue 3-0 en Draft Nokia Proprietary and Confidential
The BTS has a cooling fan and built-in heaters to provide a smooth temperature
controlling facility. The BTS software controls the heating and cooling to provide
operation conditions which are as stable as possible. Heating and cooling are
adjusted gradually to ensure low temperature gradients and noise levels. The
temperature is continuously monitored with sensors placed on active units.
The heater elements are located inside the transceiver and transmission units.
When the BTS starts up in an extremely cold environment, the units are warmed
up to the operation temperature range (-10ºC or +14ºF within each TRX) before
the actual BTS operation starts.
The fan unit generates the cooling air flow inside the BTS. The fan unit has 16
speeds, ensuring low temperature gradients and noise levels.
If the temperature of any unit rises too high, due to a broken fan unit or too hot
conditions on the site for example, the TRX issues an analysed temperature alarm
to the BSC. The master TRX then shuts down the appropriate TRX. Similarly, if
the power supply is overheated, the master TRX switches off the power for all
units. The power supply switches the power back on when the temperature has
returned to the operational range.
During operation, the master TRX starts the heating process if the internal
temperature drops below the specified limit.