Explorer GPS Receiver

Building on the 200+ years of on-orbit Viceroy® performance

General Dynamics’ Explorer Global Positioning System (GPS) Spaceborne Receiver provides position, velocity, and time information for Low Earth Orbit (LEO) and Geostationary Earth Orbit (GEO) applications. Performance and satellite visibility are enhanced through the use of dual antennas (LEO configuration only); each of the 12 GPS channels can be assigned to either antenna. The design supports an RS-422 bus interface.

Design based on legacy space qualified digital design
20 years of trouble-free spaceflight heritage
Same reliable position, velocity, time, pseudorange and carrier phase at 1Hz
Same form-factor and interface control as heritage Viceroy receiver

Features
Specifications
Literature

Features

The Explorer GPS Receiver includes all the features of our heritage Viceroy GPS Receiver. The Explorer supports user selectable parts level to tailor the mission life and cost to meet most mission needs.

Space Qualified Digital Design
Full Spaceborne Capability
Autonomous Operation
Pseudorange and Integrated Carrier Phase at One Second Rate
One PPS Clock Output Synchronized to GPS Time
Radiation Tolerant Design
12 Receive Tracking Channels
Only 56 Cubic Inches
20 to 34 VDC Operation
Improved Radiation Tolerant Digital Electronics
12 Channels Support All-in-View Tracking
Dual Antenna – Any Channel Assigned to Either Antenna (LEO only)
Fast Cold Start Mode Simplifies Integration and Autonomous Operation
Low Signal Acquisition and Tracking Supports GEO Sidelobe Tracking
Enhanced Resolution 1 Pulse per Second Output
Tailorable parts level

Specifications

Explorer GPS Receiver Data Sheet	View Document
Receiver Architecture	12 channels with enhanced fast acquisition processor Dual antenna – any channel to either antenna (LEO only) L1: 1575.42 MHz, C/A code Carrier-aided code tracking Based on legacy Viceroy architecture (hardware and software)
Input/Output	RS-422 serial I/O X.25 protocol with ECEF position, velocity, time, longitude, latitude, pseudorange, carrier phase One pulse per second (GPS, UTC, or Measurement Epoch Time) 9-pin male Micro-D for prime power 25-pin female Sub-D for command and telemetry SMA female connector for RF signal
Solution Accuracy	Autonomous Position: < 15 meters, 1 sigma (LEO) \| < 100 meters, 1 sigma (GEO) Autonomous Velocity: < 0.1 meters/second, 1 sigma (LEO) \| < 0.01 meters/second, 1 sigma (GEO) 1PPS time: < 100 ns, 1 sigma (typical)
Time to First Fix	LEO: 4 minutes, cold start GEO: 10 minutes, cold start
Orbital Dynamics	Altitude: LEO (approx 200km to 2000km) \| GEO (approx 35,800km) Velocity: up to 16,000 meters/second Acceleration: 1G+
Optional and Custom Features: Contact Factory	Time Strobe Input: < 100 ns, 1 sigma Precision internal reference Ovenized Crystal Oscillator (OCXO) Enhanced Radiation Hardening
Physical/Environmental	Size: 6.3 x 5.2 x 1.7” (160 x 132 x 43 m) Weight: 2.5 lbs (1.2 kg) max DC Power: 8 W max steady state tracking (22-34vdc) Vibration: 17 grms Shock: 3000 G Temperature: -20°C to +60°C Radiation Tolerant Design Single Event Latch-up Immune

Literature

Explorer GPS Receiver Data Sheet [PDF]

Features
Features

The Explorer GPS Receiver includes all the features of our heritage Viceroy GPS Receiver. The Explorer supports user selectable parts level to tailor the mission life and cost to meet most mission needs.
- Space Qualified Digital Design
- Full Spaceborne Capability
- Autonomous Operation
- Pseudorange and Integrated Carrier Phase at One Second Rate
- One PPS Clock Output Synchronized to GPS Time
- Radiation Tolerant Design
- 12 Receive Tracking Channels
- Only 56 Cubic Inches
- 20 to 34 VDC Operation
- Improved Radiation Tolerant Digital Electronics
- 12 Channels Support All-in-View Tracking
- Dual Antenna – Any Channel Assigned to Either Antenna (LEO only)
- Fast Cold Start Mode Simplifies Integration and Autonomous Operation
- Low Signal Acquisition and Tracking Supports GEO Sidelobe Tracking
- Enhanced Resolution 1 Pulse per Second Output
- Tailorable parts level

Specifications

Explorer GPS Receiver Data Sheet	View Document
Receiver Architecture	12 channels with enhanced fast acquisition processor Dual antenna – any channel to either antenna (LEO only) L1: 1575.42 MHz, C/A code Carrier-aided code tracking Based on legacy Viceroy architecture (hardware and software)
Input/Output	RS-422 serial I/O X.25 protocol with ECEF position, velocity, time, longitude, latitude, pseudorange, carrier phase One pulse per second (GPS, UTC, or Measurement Epoch Time) 9-pin male Micro-D for prime power 25-pin female Sub-D for command and telemetry SMA female connector for RF signal
Solution Accuracy	Autonomous Position: < 15 meters, 1 sigma (LEO) \| < 100 meters, 1 sigma (GEO) Autonomous Velocity: < 0.1 meters/second, 1 sigma (LEO) \| < 0.01 meters/second, 1 sigma (GEO) 1PPS time: < 100 ns, 1 sigma (typical)
Time to First Fix	LEO: 4 minutes, cold start GEO: 10 minutes, cold start
Orbital Dynamics	Altitude: LEO (approx 200km to 2000km) \| GEO (approx 35,800km) Velocity: up to 16,000 meters/second Acceleration: 1G+
Optional and Custom Features: Contact Factory	Time Strobe Input: < 100 ns, 1 sigma Precision internal reference Ovenized Crystal Oscillator (OCXO) Enhanced Radiation Hardening
Physical/Environmental	Size: 6.3 x 5.2 x 1.7” (160 x 132 x 43 m) Weight: 2.5 lbs (1.2 kg) max DC Power: 8 W max steady state tracking (22-34vdc) Vibration: 17 grms Shock: 3000 G Temperature: -20°C to +60°C Radiation Tolerant Design Single Event Latch-up Immune