4RF Aprisa XE, Руководство пользователя

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Configuring the terminal | 62
RX and TX Frequency
The local terminal transmit frequency must match the receive frequency of the remote terminal and the
remote terminal transmit frequency must match the receive frequency of the local terminal.
When setting the RX and TX frequency with SuperVisor, the frequency entered is automatically
resolved to the synthesizer step size for the terminal frequency band e.g. a 1400 MHz band frequency
entry of 1474,010,000 Hz will be changed to 1474,012,500 Hz (see synthesizer step size in the table
“RF specifications” on page 237).
The RX and TX frequency entered must be:
ƒ Within the frequency band limits of the chosen RF frequency band of the terminal as specified in
“RF specifications” on page 237 e.g. for a frequency band of 1400 MHz, the frequency band limits
are 1350 to 1550 MHz
ƒ
Within the TX/RX passbands of the duplexer fitted in the terminal e.g. for a frequency band of
1400 MHz, the duplexer passband is 7 MHz and the TX/RX split is > 49 MHz (see Duplexer
(bandpass) “RF specifications” on page 237).
The duplexer passband and center frequencies are written on the duplexer label.
Important: Changing the remote terminal RX or TX frequency will disable all management
communication to the remote terminal but by changing the local terminal to match the remote terminal,
the radio link will be restored as will the management communication
BUT
if the remote terminal RX or TX frequency is changed to be outside the operating range of the
terminal, changing the local terminal to match the remote terminal will not restore the radio link and
management communication
The remote terminal TX and RX frequencies cannot be changed simultaneously i.e. change one
direction and ‘Apply’ the change and then change the other direction and ‘Apply’ the change.
To change both TX and RX frequencies:
1.
Change the remote terminal RX frequency and ‘Apply’ the change. The radio link will fail.
1. Change the local terminal TX frequency to that of the remote RX frequency and ‘Apply’ the
change. The radio link will restore.
2. Change the remote terminal TX frequency and ‘Apply’ the change. The radio link will fail.
2. Change the local terminal RX frequency to that of the remote TX frequency and ‘Apply’ the
change. The radio link will restore.
Transmit power
The transmitter power is the power measured at the duplexer output port.
The transmitter power adjustment range varies depending on the Modulation type and frequency band
of the terminal (see “System performance specifications” on page 238).
Channel size
The RF channel size is a factory-configured setting determined by the Aprisa XE hardware option.
Modulation type
Both terminals must be set to the same modulation type.
When you change the modulation type in an operational terminal, traffic across the link will be
interrupted and you may need to change the cross connections capacity, as the Total Capacity of the
radio link may be exceeded.