Aria-130 Digital Key Telephone System
Issue: 1.2
Installation Manual
139
Base stations may be mounted on wall or desktop up to 600 meters away from the WTIB using a twisted
2-pair unshielded cable(0.5
φ
). The system supports max. 24 base stations.
In typical office environments, each base station has a broadcast range of 50 meters and supports an
area of 8,000 square meters. In settings where the absence of any obstruction provide perfect line of
sight conditions between a base station and wireless terminal users and there are no atmospheric
limitations, the range may increase to max.200 meters.
LEDs on the PCB of a base station provide diagnostic information for base station status.
LED Number
Meaning
Normal State
LED 1
PWR_ON
Steady _ON
LED 2
REF_ON
Steady _ON
LED 3
TX_ON
Blinking(like steady_on)
LED 4
RX_ON
Blinking
Table 5.3.4 LEDs on Base Station
Antenna Diversity
Spatial diversity at the base station is implemented by using two antennas. The antenna providing a best
signal for each time slot is selected. This is performed on the basis of the RF power level and alternatively
the quality information.
In DECT, the BER(Bit Error Ratio) is affected by multi-path propagation not only in terms of signal fading
but in terms of time dispersion, which leads to ISI(Inter Symbol Interference). Antenna diversity reduces
not only the fading probability but the effect of time dispersion.
Power Feeding
The base station is DC powered from the WTIB.
Fig 5.3.3
shows the phantom power feeding circuit
between a WTIB and a base station.
Base Station
Tx Data
Vin
Transformer
Transformer
Diode
Posister
Vout
Transformer
Transformer
Rx Data
WTIB
Figure 5.3.3 Phantom Power Feeding Circuit between WTIB and Base Station
