GNSS Modeling and Simulation

Provide Precise and Repeatable GNSS RF Signals

CAST Navigation’s GNSS simulation systems produce GNSS RF signals that provide a precise and repeatable testing signal, perfect for use either in the field or in the laboratory environment.  These systems can be used for a wide range of testing and integration verification applications and they are an ideal choice for stimulating military or commercial devices where only GNSS signals are needed.  Our simulators are powered by proprietary multi-frequency, multi-constellation GNSS RF signal generation technology.  This technology provides you with highly accurate and fully programmable signals along with advanced vehicle trajectory capabilities allowing you to custom tailor parameters and trajectories to meet your simulation requirements.

The CAST-GNSS simulators can be configured to deliver a full constellation of GNSS satellites, with up to 16 satellites in view per GNSS satellite constellation signal type, per composite signal RF output element.  CAST GNSS systems can be configured to simultaneously provide up to four different constellation types such as GPS (including Y-Code, SAASM, M-Code AES and MNSA), Beidou, and GLONASS on each antenna element.

GNSS System Features

Provides precise and repeatable GNSS RF signals that can be utilized for testing in a laboratory or field-type environment

Systems are capable of simulating either static or dynamic motion for terrestrial, aquatic, airborne and space-based vehicles

Signal types supported: GPS, BeiDou , GLONASS, SBAS

Customizable solutions allow configurations of GNSS signals to meet your requirements

Real World Simulation

The CAST comprehensive and intuitive graphical interface allows the selection of a wide variety of vehicle types and to simulate both static and dynamic motion profiles.Depending on simulation requirements, users can choose from airborne, terrestrial, aquatic (including the sea-state), or space-based orbital vehicles.

Trajectories can be defined by a scenario profile using our advanced graphical interface, or by vehicle type and constellation parameters, providing a Real-time 6-DOF trajectory via an external interface. The system can also generate a motion profile from previously recorded data collected from an external source.

Users can also specify and customize the Scenario Date and Time, Location, Almanac, Ephemeris, Atmospheric Delays, Multipath, Spoofing, RF Output Power Levels, Antenna Gain Pattern, Vehicle Silhouette, Data and Health flags, and other criteria.

CAST system’s performance evaluation module provides the ability to compare raw measurements and filtered data received from the GPS navigation system under test with user vehicle truth data. This provides post-test receiver analysis and truth report generation capabilities that can be archived for future reference.

Thanks to a modular design approach, CAST GNSS system configurations are flexible and can be customized to meet changing or expanding requirements. In most cases, our GNSS systems can support up to 8 additional elements of composite RF output per system. Each RF output “element” can be configured to provide a different vehicle type, trajectory or modified navigation signal. In addition, multiple CAST systems can be synchronized together to maximize robust and flexible simulation environments.

CAST Navigation’s GNSS simulation systems also feature the ability to add a variety of options, including additional Signal, Inertial, Terrain Obscuration and Signal Interference capabilities, to meet all types of challenging simulation requirements.

CAST GNSS Specifications

Output Signal Types

GPS: L1, L2, L2C, L5, C/A-Code, P-Code, Y-Code, SAASM, M-Code AES, M-Code MNSA
BeiDou: B1I, B2I

Maximum Dynamics

Velocity: > 60,000 m/s
Acceleration: ± 150,000 m/s2
Jerk: ± 150,000 m/s3

Signal Output Levels (Nominal)

GPS:               -160 dBW
GLONASS:    -161 dBW
Beidou:          -163 dBW
SBAS:            -160 dBW

Signal Level Control

Range:  ± 30 dB
Resolution:  0.1 dB

L1/L2 Differential Delay

Range:  ± 0.3 m
Resolution:  < 1 mm

Signal Accuracy

Pseudorange:  1 mm
Pseudorange Rate:  1 mm/s
Delta Pseudorange:  1 mm
Interchannel Bias:  < 1 mm
Uncontrolled Bias:  < 1 mm
Bias Repeatability (initial):  < 1 mm
Bias Stability (operational):  < 1 mm

Signal Quality

Spurious:  < -45 dBc
Harmonics:  < -50 dBc
Reference Oscillator:  10MHz OCXO
Frequency Stability:  3×10-9 per day

System Options

6-DOF Real Time Interface
L2C, L5
Remote Control DLL
Additional Elements
Inertial Interface
Avionics Interfaces