Glenayre Electronics Inc. GL-T8311SA Manual Do Utilizador
Glenayre Document Number: 9110.00166
GL-T8xx1 Transmitter System
Revision K: 08/30/99
DESCRIPTION
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Copyright © 1999 Glenayre
Page: 3-3
3.3
Simplified Paging-Site Functional Description
3.3.1
Paging Site
The following paragraphs provide a block diagram-level functional description of a typical
paging site.
paging site.
Refer to Figure 3-3, Transmitter Functional Diagram. This figure shows basic signal flows
between the various paging site equipment pieces. The communications device which the
transmitter uses in order to communicate with the control site is not shown and may vary
from application to application.
between the various paging site equipment pieces. The communications device which the
transmitter uses in order to communicate with the control site is not shown and may vary
from application to application.
3.3.2
Communications Equipment and Transmitter Controller
A link receiver, satellite receiver, microwave drop, telephone link, or other similar device
is used for communication between the transmitter controller and the control site. The
particular device depends on the application.
is used for communication between the transmitter controller and the control site. The
particular device depends on the application.
The transmitter controller is typically a GL-C2000 model. There are various ways of inter-
facing the transmitter controller to the I/O portions of the exciter. Refer to the transmitter
controller manual and the exciter manual for details.
facing the transmitter controller to the I/O portions of the exciter. Refer to the transmitter
controller manual and the exciter manual for details.
3.3.3
Paging Transmitter
The paging transmitter converts the signal from the transmitter controller into modulated
and amplified RF. Depending on the type of transmitter controller-to-exciter interface
which is used, the modulation information from the transmitter may be audio, modem
signals (analog or digital), or a digitized representation of the original signal. In any case,
all analog signals are ultimately converted to digital form at some point between the paging
terminal and the DSP modulator in the exciter.
and amplified RF. Depending on the type of transmitter controller-to-exciter interface
which is used, the modulation information from the transmitter may be audio, modem
signals (analog or digital), or a digitized representation of the original signal. In any case,
all analog signals are ultimately converted to digital form at some point between the paging
terminal and the DSP modulator in the exciter.
Operation is in response to commands from the transmitter controller via the DSP exciter.
The transmitter monitors its functions and reports its status to the VDT via the exciter. The
transmitter controller permits the transmitter to be controlled and monitored from a remote
location. Local control and monitoring is performed through a VT-100 video display
terminal (VDT).
The transmitter monitors its functions and reports its status to the VDT via the exciter. The
transmitter controller permits the transmitter to be controlled and monitored from a remote
location. Local control and monitoring is performed through a VT-100 video display
terminal (VDT).
3.3.3.1
DSP Exciter
The DSP exciter combines functions of an RF exciter and a PA controller. The exciter
generates modulation using digital signal processing (DSP) to achieve accurate, stable
modulation that does not vary with time or temperature. The PA-control section monitors
transmitter status signals in the form of fault logic and voltage samples. The microprocessor
in the exciter reports PA status to the transmitter controller, VDT, and the exciter front
panel. If a malfunction occurs, the transmitter enters a reduced operating condition,
depending on the seriousness of the fault. PA control and status monitoring are performed
by the microprocessor, which consolidates control logic from the transmitter controller or
the locally operated VDT. Both the exciter and transmitter controller receive continuous
status reports from the microprocessor. The exciter is the control and status-monitoring
interface between the transmitter and the user.
generates modulation using digital signal processing (DSP) to achieve accurate, stable
modulation that does not vary with time or temperature. The PA-control section monitors
transmitter status signals in the form of fault logic and voltage samples. The microprocessor
in the exciter reports PA status to the transmitter controller, VDT, and the exciter front
panel. If a malfunction occurs, the transmitter enters a reduced operating condition,
depending on the seriousness of the fault. PA control and status monitoring are performed
by the microprocessor, which consolidates control logic from the transmitter controller or
the locally operated VDT. Both the exciter and transmitter controller receive continuous
status reports from the microprocessor. The exciter is the control and status-monitoring
interface between the transmitter and the user.