AeroComm Corporation LX2400 Manuel D’Utilisation
THEORY OF OPERATION
09/22/00
Preliminary
Preliminary
11
3.2.4 In Range
The IN_RANGE pin at the connector will be driven low when a Client radio is in range of a Server on the
same channel. If the Client cannot hear a LX2400S Server for 10 S, the LX2400S Client drives the IN_RANGE
pin high and enters a search mode looking for a LX2400S Server. As soon as it detects a Server, the
IN_RANGE pin will be driven low. The LX2400 Server can determine what Clients are in range by the
Server’s Host software polling the LX2400S Client’s Host.
same channel. If the Client cannot hear a LX2400S Server for 10 S, the LX2400S Client drives the IN_RANGE
pin high and enters a search mode looking for a LX2400S Server. As soon as it detects a Server, the
IN_RANGE pin will be driven low. The LX2400 Server can determine what Clients are in range by the
Server’s Host software polling the LX2400S Client’s Host.
3.2.5 RSSI
Received Signal Strength Indicator is used by the Host as an indication of instantaneous signal strength at
the receiver. The Host must calibrate RSSI without a signal being presented to the receiver. Figure 1 shows
approximate RSSI performance. The RSSI pin requires the Host to provide a 27k
the receiver. The Host must calibrate RSSI without a signal being presented to the receiver. Figure 1 shows
approximate RSSI performance. The RSSI pin requires the Host to provide a 27k
Ω
pull-down to ground.
Output is 1.20V to 4.50V.
3.2.6
Figure 1 - RSSI Voltage vs. Received Signal Strength
-100
-90
-80
-70
-60
-50
-40
-30
-20
-10
0
1.2
1.3
1.57
2.3
3.8
4.5
Voltage (VDC)
Signal at Receiver (dBm)