Harry wrote:In general high update rates come at the price of accuracy. The VBOX Sport should play in a different league however and I hope to see better update rates AND accuracy / lock stability.
- Harry
Could you clarify that please? I had thought that the higher update rate of the external units delivered greater accuracy of position. The readings in GPS Buddy seem to support that view with accuracy reported as good as 6ft with the Dual 150 unit. If that is not the case what is the advantage of using them?
How will the Vbox differ, apart from the obvious 20Hz update rate?
Accuracy is defined by the max deviation of the real position the GPS delivers for each individual fix (statistic statement, true for at least 95% of all fixes). So this term is completely independent of update rates - it is about individual fixes.
"Update rates come at a price of accuracy" is meant for comparable technical effort / chip sets and clock rates. It is certainly always possible to improve both dimension by investing more technical effort. As a cite from a person deeper in GPS hardware topics: "For higher accuracy you will need a DGPS lock and that is usually a problem due to the amount of calculations the GPS engine needs to do within the small amount of time available with high update rates."
Both the Emprum UltiMate GPS and the Dual XGPS150 delivery higher accuracy *and* higher update rates. But both represent a lot bigger investment in hardware compared to a combined RF chip in modern smart phones. I assume the VBOX Sport goes even further. Details need to come from RL, I have no insights here.
Thanks, its obvious when you think about it. I think I was considering the accuracy of the line plotted v update rates. A faster updates will give a more accurate trace through a bend, yes?
