Glenayre Electronics Inc. GL-T8311SA Manual Do Utilizador
GL-T8xx1 Transmitter System
Glenayre Document Number: 9110.00166
DESCRIPTION
Revision K: 08/30/99
Page: 3-8
Copyright © 1999 Glenayre
3.4
Site Signal Flows
3.4.1
Site RF-Signal Flow
The on-frequency carrier is created by the VCO circuitry in the DSP exciter. It is then
modulated with paging information, amplified, and sent to the PA via connector J3 on the
back of the DSP exciter. Through coaxial cable, the carrier goes to the back of the PA,
where it is further amplified to a preset level under control of a microprocessor within the
exciter. The amplified carrier is cabled from the PA output to the antenna system. Note that
some installations have a ten-MHz reference signal cabled from the transmitter controller
to connector J8 on the back of the DSP exciter.
modulated with paging information, amplified, and sent to the PA via connector J3 on the
back of the DSP exciter. Through coaxial cable, the carrier goes to the back of the PA,
where it is further amplified to a preset level under control of a microprocessor within the
exciter. The amplified carrier is cabled from the PA output to the antenna system. Note that
some installations have a ten-MHz reference signal cabled from the transmitter controller
to connector J8 on the back of the DSP exciter.
3.4.2
Site Audio-Signal Flow
Modulation information arrives at the site either through a link receiver or by wireline. The
signal can be either analog or digital and is first routed through the transmitter controller,
which checks for and responds to appropriate embedded commands. Paging information is
supplied to the exciter. The exciter modulates this signal using digital signal processing,
then up-converts this modulated signal to final output frequency. This modulated RF from
the exciter is supplied to the PA, which amplifies the signal to the RF output level. This
modulated, amplified RF from the PA is supplied to an antenna network for transmission.
An audio-monitoring speaker is available on the Glenayre RL-XX3-series receiver.
signal can be either analog or digital and is first routed through the transmitter controller,
which checks for and responds to appropriate embedded commands. Paging information is
supplied to the exciter. The exciter modulates this signal using digital signal processing,
then up-converts this modulated signal to final output frequency. This modulated RF from
the exciter is supplied to the PA, which amplifies the signal to the RF output level. This
modulated, amplified RF from the PA is supplied to an antenna network for transmission.
An audio-monitoring speaker is available on the Glenayre RL-XX3-series receiver.
3.4.3
Site Control-Signal Flow
Transmitter paging-site control is done two ways: remotely (normal operation), and locally.
In either case, the paging transmitter is keyed when the transmitter controller commands it,
via the DSP exciter, to key.
In either case, the paging transmitter is keyed when the transmitter controller commands it,
via the DSP exciter, to key.
Control functions are shared by the transmitter controller and the DSP exciter, which
controls the power amplifier. The DSP exciter also controls the power amplifier locally by
responding to commands from the VDT.
controls the power amplifier. The DSP exciter also controls the power amplifier locally by
responding to commands from the VDT.
Control signals enter and exit the paging site via the transmitter controller, which has
overall control of the paging site. The transmitter controller is part of the larger paging
control system even though it is racked with paging-site equipment. The transmitter
controller has control functions which include those listed below.
overall control of the paging site. The transmitter controller is part of the larger paging
control system even though it is racked with paging-site equipment. The transmitter
controller has control functions which include those listed below.
• transmitter alarm gathering
• transmitter alarm dispatching
• simulcast parameter implementation
• remote transmitter operation interface.
Remote control of the paging site is done through commands being sent to the transmitter
controller from the external paging control system.
controller from the external paging control system.
Control commands originating from a remote site are supplied to the exciter through the
controlling device. Control and setup commands may be applied to the exciter locally
through the VDT. A microprocessor within the exciter interprets each command and
responds by performing the appropriate function.
controlling device. Control and setup commands may be applied to the exciter locally
through the VDT. A microprocessor within the exciter interprets each command and
responds by performing the appropriate function.