The dwell time in
GNSS
A satellite navigation or satnav system is a system that uses satellites to provide autonomous geo-spatial positioning. It allows satellite navigation devices to determine their location (longitude, latitude, and altitude/elevation) to high pre ...
is the time required to test for the presence of a
satellite signal for a certain combination of parameters. A search process detects whether a GNSS
satellite
A satellite or artificial satellite is an object intentionally placed into orbit in outer space. Except for passive satellites, most satellites have an electricity generation system for equipment on board, such as solar panels or radioisotope ...
is present or not in an area of the sky, based on
correlation
In statistics, correlation or dependence is any statistical relationship, whether causal or not, between two random variables or bivariate data. Although in the broadest sense, "correlation" may indicate any type of association, in statistics ...
of a received signal with a reference signal stored in the
receiver.
The dwell times are associated with the performance of a certain
detector
A sensor is a device that produces an output signal for the purpose of sensing a physical phenomenon.
In the broadest definition, a sensor is a device, module, machine, or subsystem that detects events or changes in its environment and sends ...
. They can be classified into single dwell times, when the decision is taken in one step, and multiple dwell times,
[Lohan2004] when the decision is taken in two or more steps.
References
Works cited
* N. Couronneau, P.J. Duffett-Smith, and A. Mitelman, Calculating Time-to-First-Fix, GPS World, Nov 2011 (GPS World 2011)
* E.S. Lohan, A. Lakhzouri, and M. Renfors, ''Selection of the multiple-dwell hybrid-search strategy for the acquisition of Galileo signals in fading channels'', in CDROM Proc. of IEEE PIMRC, Sep 2004. (Lohan2004)
Global Positioning System
Time
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