Spirent Sim3D provides realistic multipath simulation

3D modeling solution creates true-to-life synthetic environments for more accurate testing.

Spirent Communications plc has launched an innovative multipath simulation solution, Spirent Sim3D. The 3D modeling solution enables the testing of realistic multipath and obscuration effects on GNSS signals in a true-to-life synthetic environment.

Sim3D is suitable for use by automotive, chipset, handset and receiver manufacturers, as well as in aerospace, military, mining and precision agricultural applications.

Spirent will demonstrate Sim3D at ION GNSS+ 2019 in Miami, Florida, Sept. 16-20.

Studying multipath. Historically, researchers and developers of GNSS receivers have had to rely on statistical models and time-consuming field testing to study the effects of multipath on GNSS signals.

With Sim3D, the industry can now gain a greater understanding of the impact of multipath and obscuration in a broad range of real-life situations. It offers the level of control and traceability needed for developers to improve their customers’ experience in the most challenging environments.

A satellite signal reflecting off surfaces, such as a building, a high-sided vehicle, a tree, or even the ground, alters the pseudorange, causing the signal to arrive at the receiver slightly later than line-of-sight signals.

Without proper mitigation, this can cause a receiver to output an inaccurate position.

“Obscuration and multipath effects are one of the major obstacles faced by engineers trying to achieve accurate GNSS positioning solutions,” said Spirent Managing Director of Positioning Martin Foulger. “The accelerating development of connected autonomous vehicles and other precision applications means the need to test for higher precision positioning, navigation and timing in a variety of environments is growing rapidly. Sim3D is an important and timely development.”

Image: Spirent

Simulation of 3D environments. The unique system has been developed in partnership with OKTAL Synthetic Environment. It offers the ability to simulate multipath effects in a range of lifelike geo-typical environments, using different models to recreate locations such as urban highway, an inner city or a forest. Geo-specific models of real locations can also be commissioned.

During simulation with Sim3D, the GNSS signals interact with fully customizable 3D environments to simulate real-life applications in operation, like a vehicle on a highway, or a wearable device on a pedestrian.

This gives a level of detail, control and realism in testing not previously available. Such realistic multipath and obscuration simulation will add greater credibility to GNSS testing and assure that developed solutions are optimized and tested for their intended environments.

“As vehicles become increasingly autonomous, it’s vital to get a more detailed understanding of the effects of obscuration and multipath on a vehicle’s ability to generate an accurate GNSS-based position” explained Foulger. “Statistical models cannot sufficiently achieve this.

“Sim3D’s ability to realistically simulate different environments provides this greater accuracy and brings a host of benefits to researchers and developers of autonomous vehicle systems,” Foulger said. “It will help to guide critical design decisions like where to place the GNSS antenna on the vehicle, what GNSS receiver to use and when to hand over to other position sensors as GNSS signals degrade.”