Installation Manual

Parameter Specifications
VHF UHF
7K60F7E
7K60F7W
7K60FXW
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SLR 1000 Repeater on page
28
1.5
Repeater Theory of Operation
The SLR 1000 Repeater provides the radio frequency (RF) link between the network infrastructure and
the subscriber radios.
The repeater acquires inbound signals through its external receive (Rx) antenna and then amplifies,
filters, and demodulates the signals into data or voice packets. From that point, the data is either
forwarded to the repeater’s transmitter to subscriber radios, and/or the data is delivered through a
wired interface for distribution to networked repeaters, consoles, or other networked infrastructure.
The repeater consists of a single transceiver board. The transceiver board is comprised of three
subsystems:
Receiver Subsystem
The Receiver subsystem is a dual heterodyne Receiver which receives the RF signal from the
subscriber’s transmitter. It then converts the resulting final Intermediate Frequency (IF) from an
analog signal to that of a digital word in IQ signal format. Finally, the Receiver delivers the IQ
signal, through the Synchronous Serial Interface (SSI) bus, to the Station Control subsystem for
demodulation. Also, the Receiver subsystem provides its own metering and diagnostics through
software, and self-contained calibration (no field tuning is needed for the Receiver subsystem).
Transmitter Subsystem
The Transmitter subsystem converts a two-port base band data signal, sent over the SSI bus from
the Station Control subsystem, to an analog signal representation. The Exciter subsystem
modulates the analog signal with a low-power RF transmitter carrier. The power modulated RF
carrier is then amplified and delivered to the antenna. The Exciter subsystem constitutes the
transmitter of the repeater. Also, the Exciter subsystem provides its own metering and diagnostics
through software, and a self-contained calibration (no field tuning is needed for the Exciter
subsystem).
The Transmitter subsystem delivers the amplified signal to the transmitter antenna port at a power
level within the rated power band of the repeater, for transmission to the subscriber radios. In
addition, it provides the following hardware functions for the repeater.
• Harmonic attenuation
• Inter-modulation attenuation (IMA) suppression
• RF power control (primary means)
• Meters for diagnostics
• Power rollback for temperature
• Self-Contained calibration (no field alignment is needed for the power amplifier).
MN003557A01-AF
Chapter 1: SLR 1000 Repeater
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