User's Manual

Table Of Contents
Printed Documentation
144
Set RX Sensitivity without a DACU
Tools and equipment needed.
Item Description Recommended Model Quantity
1 Digital Multimeter Fluke 77 1
2 ST Test Unit, SIU with Modified Antenna at
appropriate band
1
3 30dB Attenuators;
5W
Mini Circuits: BN-N30W5 2
4 30dB Attenuators;
2W
M/A-COM:2082 6044 30:2W 2
5 Two Way Power
Divider
Mini Circuits: ZAPD-4-S 1
6 50 ohm Termination
10W
Arra N9510 1
7 Adaptor; N-SMA Huber & Suhner 33N-SMA-50-1 1
8 Adaptor; N-SMA Huber & Suhner 31N-SMA-50-1 1
9 Huber & Suhner Sucoflex 104; 0.5m 2
10
Co-ax Cables
Huber & Suhner Sucoflex 104; 4.0m 1
11 Cable SMA-MCX Huber & Suhner 30-05918-10 1
12 RF Power Meter Marconi 6970 1
13 Power Sensor Marconi/RFI 6970&5 6932/900 1
RX Sensitivity (Test 6)
The RX sensitivity is set according to the required CT RX level. It is important to note that the
lower the modulation rate the further the geographical spread. For maximum range the
AS4020 should use QPSK 1/2. Higher data rates may be achieved using higher orders of
modulation but the range will lessen as the modulation rate increase. This level is determined
as part of the planning function and takes into consideration the highest modulation rate to be
offered and the noise floor predicted in the planning stage.
The RX Level is set dependant on the highest operational modulation rate as follows. By
undertaking an appropriate level of RF planning the level is optimised in order to balance
uplink data rate and system range.
Typical levels are shown below for two network configuration scenarios:
For networks where only a single RF Channel is operating, or only adjacent + one RF
Channels are used (no co or adjacent channel interference), the following CT Rx levels apply:
Rx Level (dBm / RW)
Modulation
Code
Rate
Below 3GHz
Above
3GHz
Session
ids for
LAT TE
command
in Mode 3
QPSK 1/2 -105 dBm -103dBm 58 or 59
QPSK 3/4 -103 dBm -101dBm 56 or 57
16QAM 1/2 -97 dBm -95dBm 54 or 55
16QAM 3/4 -93 dBm (see note 1) -91dBm 52 or 53
64QAM 3/4 Not supported on the uplink
Table 1
Note 1: Note, 16QAM ¾ is only supported on the uplink with up to 7RW Codes Active.