05 Nov 2020
Super-S technology optimizes power consumption and accuracy with weak signals and small antennas
Super-S technology addresses two common challenges encountered across industrial tracking and wearable use cases: weak GNSS signals and poor antenna placement. Poor weather, obstructed sky view, and urban canyons negatively impact the quality of the GNSS signals that reach the positioning receiver, reducing positioning performance. Additionally, the location and the size of the GNSS antennas used are heavily dependent on the application type, size and design constraints imposed by the device makers, and financial constraints on the end-product. These design choices significantly impact the end-product’s positioning performance.
Super-S (Super-Signal) technology combines 2 different measures to cope with these situations.
The higher the RF sensitivity of the GNSS receiver, the better it can operate under low signal conditions. During operation, GNSS receivers can be in two operational phases: the acquisition phase and the tracking phase. After startup, the GNSS first enters acquisition phase. Once it has achieved a valid position, the GNSS receiver moves to the tracking phase.
In order to deal with weak signals, the GNSS receiver’s sensitivity needs to be good in both phases. During the acquisition phase, higher sensitivity lowers the time to first fix (TTFF), achieving a position fix with higher probability while consuming less power. The power consumption in the acquisition phase is higher than during the tracking phase.
In the tracking phase, the GNSS receiver’s objective is to avoid losing its valid position and remain in the tracking phase. If it loses its position fix, the GNSS stops proving position information and has to reacquire a position fix in acquisition phase.
u-blox GNSS receivers supporting Super-S provide best-in-class sensitivity values for both phases.
A multi-GNSS receiver concurrently receives signals from more than one constellation and judges which signals to use for tracking. In good signal conditions, the choice of signals is vast, especially if the receiver is able to concurrently track four GNSS constellations.
In the case of a weak signal scenario, the number of available signals shrinks significantly. Weak signal compensation improves the accuracy of position and speed information significantly over conventional GNSS receivers.
Drive tests conducted using a u-blox M9 GNSS receiver equipped with weak signal compensation demonstrated significant improvements in both positioning and velocity readings.
|Indoor antenna||Indoor antenna + weak signal compensation||Improvement|
|Dynamic position accuracy (2D CEP68)||~15 m||~11 m||> 25%|
|Dynamic speed accuracy (2D CEP68)||~0.8 m/s||~0.5 m/s||> 35%|