DGPS Systems

The SC1000A Differential GNSS transmitter allows carrier power adjustment from 50 to 1000 Watts. The transmitter uses switching technology in the power amplifiers and modulator regulator resulting in a highly efficient system in a relatively small package.

The exciter portion of the transmitter consists of an MSK Interface board that accepts a 283.5 kHz to 325 kHz sine wave input signal ranging from 0 to 15 dBm.  The MSK Interface board squares, monitors and distributes this signal to the power amplifiers.

The completely redundant RF power sections of each drawer consist of independent 1000 Watt assemblies. Each 500 Watt sub-assembly has an output filter, a switching power amplifier, and a switching modulator/regulator. The RF output of each sub-assembly is combined to provide a 1000 Watt signal to the Antenna Coupler.

The SC1000A also contains a Renesas microprocessor-controlled Automatic Transfer Unit / RIM Controller, Interface I/O panel, and an RF output panel housed in a single 19-inch rack cabinet.

The RIM Controller uses RSIM commands which allow the unit to control up to 24 external devices, through relay contacts, monitor up to 40 external devices such as intrusion alarms, temperature, and humidity sensors, log Built-In Test Equipment data, and communicate with a Reference Station using an Ethernet-ready interface.

The RIM Controller provides continuous monitoring of critical parameters to the Reference Station such as Forward and Reflected Power, VSWR, Antenna Current, and system faults.

The SC1000A works in conjunction with the PV1000 Antenna Coupler to provide a near-perfect Resistive Match and Series Resonant Tune point for the antenna system utilized.  As antenna system resistance changes throughout the day, the SC1000A and PV1000 work together to maintain a constant field strength output from the antenna when the transmitter is set to Automatic Level Control mode.

Features

• The RSIM motherboard now incorporates all control relays, monitor state isolators, transmitter metering, and system calibration. The microprocessor, a powerful MC16C series Renesas platform, is mounted on a separate board.  No extender cards required
• The Master Controller allows for firmware upgrades without the need to remove the microprocessor.
• 4 line by 40 character LCD makes setup and monitoring of system BITE information easy to view
• System functions such as power level adjustment are carried out on the front panel’s keypad
• Communication is accomplished with an internal RS485 to Ethernet converter making the transmitter “Network Ready” for ease of interface and control
• RS485 port added to allow communication with a modern “Intelligent ATU”
• Added Automatic Level Control  (ALC) provides a stable power level when used with SAC’s Intelligent ATU and ALC is engaged
• Intelligent ATU can be adjusted using the transmitter’s front panel keypad controls
• Housed in a 36 Rack Unit Cabinet with casters for easy movement and installation
• 18 Rack Units Available for Customer’s DGNSS Equipment
• Reliable Solid-State relays used to control AC 

This Differential GPS transmitter has carrier power adjustable from 10 to 200 Watts. The transmitter uses switching technology in the power amplifiers and modulator/regulator modules resulting in a highly efficient system in a small package.

The exciter portion consists of an interface for a 283.5 to 325 kHz input signal 0-15 dBm and a monitor circuit.

The power portion of each transmitter consists of an independent 200 Watt system. Each system has an output filter, a switching power amplifier, and a switching modulator/regulator.

The SC200 has the ability to operate with dual antennas and ATU’s. Antenna selection is either done locally or through an RSIM command.

The SC200 Dual consists of two independent SC200 transmitters and an Automatic Transfer Unit / RSIM Controller designed for mounting in a standard 19-inch rack cabinet.

For use with the PC1000D/4 Antenna Tuning Unit.