GNSSTA as a receiver for NTS-3 experimentation
Shawn Miller, The MITRE Corporation
Alternate Number 3
The Navigation Technology Satellite 3 (NTS-3) is a space vehicle that will transmit a wide variety of newly developed experimental PNT signals. This program requires a receiver with the flexibility and reconfigurability to add support for these new signals and support the experiment plan. New receiver capabilities must be rapidly integrated in parallel with space and ground segment development in order to maximize the number of experiments that can be supported.
These unique receiver requirements are a good match for a receiver implemented on a software defined radio (SDR). The government-owned Global Navigation Satellite System Test Architecture (GNSSTA) SDR was selected as the receiver for processing these experimental signals based on its maturity and inherent flexibility. GNSSTA will be used pre-launch to verify the RF transmission of the new experimental waveforms from the space vehicle. GNSSTA will also serve a separate post-launch role by demonstrating the benefits and operational utility of the new signals and supporting experiments developed by the advanced signals team.
This presentation includes an overview of GNSSTA capabilities and plans for its role in supporting NTS-3. This includes a description of the software-only real-time implementation of GNSSTA, with an overview of the advantages, challenges, and limitations with this approach. The first experimental signal that has been implemented in GNSSTA is the new Chimera authentication signal (IS-AGT-100). To highlight the unique challenges of adding support for experimental signals, a detailed description of the changes to GNSSTA that were required to add Chimera support is provided.