Record real-world GNSS signals for positioning and navigation testing

June 22, 2016 // By Graham Prophet
This portable unit enables high resolution RF sampling of Global Navigation Satellite System (GNSS) bands to enable repeatable testing with ful real-world effects.

Spirent Communications’ GSS6450 RF record and playback system (RPS) systems capture the rich, real-world radio frequency environment and bring it into the lab. This enables receiver, system and application technology developers to optimize performance and robustness. It combines high resolution, 16-bit wide band sampling in a portable unit measuring 22 x 20 x 7.3 cm and weighing 2 kg. The high resolution capability means it can capture a more detailed RF environment, including RF interference, complex atmospheric scintillation and space weather impacts on the GNSS signal, so users can improve receiver performance against these signals. The compact size makes it ideal for capturing data in the field such as on foot or in vehicles, and easily portable for when travelling.

 

“The GSS6450 offers high resolution in a small self-contained battery powered unit” said Rahul Gupta, commercial segment lead for Spirent's positioning division. “Until now, high resolution record and playback systems have been mains powered and not designed for in-field use. The GSS6450 changes that, enabling a range of signal powers and characteristics to be sampled, recorded, brought into the lab and replayed.”

 

It offers a choice of 4-, 8-, or 16-bit I/Q quantization, and a 10-, 30-, or 50 MHz recording bandwidth. Up to four GNSS frequency bands can be recorded simultaneously, making the GSS6450 suitable for a wide range of applications, from testing new devices, such as wearable tech and unmanned vehicles, to chipset development using new GNSS frequencies, and high-end system test. The 16-bit I/Q quantization option gives up to 96 dB of dynamic range, so it can also be used for interference analysis and improving receiver resilience to GPS jamming.

 

The GSS6450 is also capable of recording additional non-RF sources including inertial sensor outputs, dead reckoning, and up to four video streams. Long recordings are achieved using the up to 4 TB of on-board storage. An additional 8TB of RAID storage can also be