Trimble® Floodlight™ Satellite Shadow Reduction Technology

Article source: Trimble

Satellite shadow is the number one problem for data collection teams needing high accuracy in difficult GNSS conditions. Trimble® Floodlight™ satellite shadow reduction technology is the solution— delivering dramatic improvements to accuracy and position availability when working in urban canyons and under tree canopy. This is a promotional video from Trimble about this technology:

WHAT IS SATELLITE SHADOW?
Satellite shadow occurs when an obstacle between a GNSS satellite and a receiver stops the receiver from tracking the satellite effectively. As more satellites are blocked from view, it becomes progressively more difficult for the receiver to compute accurate positions. In extreme cases there are simply too few satellites in view to compute positions at all.

HOW DOES FLOODLIGHT TECHNOLOGY MITIGATE SATELLITE SHADOW?
Trimble Floodlight technology reduces the effects of satellite shadow in three ways:

1. By combining GPS and GLONASS tracking, satellite availability is increased by up to 60% over GPS-only positioning.
2. Advanced tracking algorithms speed up signal acquisition and ensure more stable tracking of satellites with weakened signals. With steadier tracking comes smoother positioning that is less prone to drop-outs and spikes caused by erratic satellite tracking.
3. Floodlight technology uses altitude-constrained positioning to reduce the impact of weakened or blocked signals. This technique limits the impact of weak signals, allows 3D positioning with fewer satellites, and improves horizontal and vertical accuracy.

Floodlight technology is compatible with real time and postprocessed workflows. There is no extra configuration, back-office processing, or quality control required—it just works.

WHY IS FLOODLIGHT TECHNOLOGY BETTER THAN OTHER TECHNIQUES TO IMPROVE POSITION AVAILABILITY?

Receivers that address satellite shadow by offering GPS and GLONASS positioning are only solving part of the problem.

Other solutions that use lower quality thresholds may increase position yield in obstructed conditions, but do so at the expense of accuracy. Floodlight technology tackles satellite shadow by improving satellite visibility and tracking while safeguarding against the effects of weak satellite signals on position quality— achieving the best possible position.

Tags: Floodlight

Category: Trimble

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