OpenStreetMap 開放街圖
WOHOO... i've just read about gps techology.. to understand its capabilities and limitations.. witch means that for us consumers, today, the best resolution we have is 2m
enter cg1950 chipset from st-ericsson
i've never heard of this company before but they have produced a very small chipset that can track both gps and glonass satellites.. this will be availabel in consumer producs in Q3 2011.. then we will have resolutions of a couple of centimeters.. wonderful..
what lovely detail we then can have on our openstreetmap!
討論
由 LivingWithDragons 於 2011年05月20日 10時46分 發表的評論
We can have amazing detail now, but detail != precision != accuracy.
Also precision isn't great if people edit the detail too realign it to aerial imagery.
由 Vincent de Phily 於 2011年05月20日 12時11分 發表的評論
Wonder where you get the "couple of centimeters" metric from. I've had a look at all this and, while a combined system will bring better accuracy, it's not going to be sub-meter yet. Probably have to wait for a chip that does GPS+GLONASS+GALILEO :)
由 RGPS 於 2011年05月20日 22時11分 發表的評論
well, i use from a long time, the 818XT Qstarz antenna ... but DGPS + 5Hz is the better way (and the cheap, too...).
1Hz GPS is poor (like my MTKv1 Holux...)
由 imroy 於 2011年05月24日 16時22分 發表的評論
I don't think simply adding more satellites from other systems will achieve very much in terms of accuracy. It will give better coverage and some of the errors will average out, but nothing huge.
Instead, I'm looking forward to the L2C signal of the new GPS satellites due to be launched in a few years. Then GPS receivers will be able to measure the signal delay added by passage through the ionosphere. I'm not sure what sort of accuracy that will allow, perhaps sub-metre.
(Look up "GPS modernization" on Wikipedia)