Silicon Investor (SI) -- The First Internet Community

STOCKTALK

We've detected that you're using an ad content blocking browser plug-in or feature. Ads provide a critical source of revenue to the continued operation of Silicon Investor. We ask that you disable ad blocking while on Silicon Investor in the best interests of our community. If you are not using an ad blocker but are still receiving this message, make sure your browser's tracking protection is set to the 'standard' level.

Technology Stocks : Nokia (NOK) -- Ignore unavailable to you. Want to Upgrade?

To: 49thMIMOMander who wrote (13924)	7/18/2001 12:02:06 AM
From: Ruffian	Respond to of 34857

You are a legend in your own mind..........congrats///

To: 49thMIMOMander who wrote (13924)	7/18/2001 2:38:23 AM
From: mightylakers	Respond to of 34857

SnapTrack is not conventional use of GPS. It also uses the arrival time of the forward link to help to narrow down the search of the GPS signal, also reduce the number of birds from 4 to 2. With this hybrid approach, the sensitivity of the GPS receiver is also improved. GPS is not rapid, except in the desert and with the antenna in the right position, taped to the roof SnapTrack can be used in heavily blocked area. NTT DoCoMo is using it for commercial daily use. And guess what there seems to be no desert in Japan. Even in those highly blocked areas, it takes just a few seconds to get the position.

To: 49thMIMOMander who wrote (13924)	7/18/2001 5:32:47 AM
From: ronho	Read Replies (1) \| Respond to of 34857

llmarinen. Why are you in denial about Snap Track?? It is a proven technology that is well recognized to work well. Also it preserves privacy pecause networks using it rather than triangulation do not have the capacity to locate your phone based on request by government agencies, private detectives etc. Your location is determined by your phone and sent back to the network only when you wish to do this. Soon all the European users will be tracked around their country by big brother's computers which take continuous location data from their always on GPRS phones. That way big brother in the European Parliment can take better care of them.

To: 49thMIMOMander who wrote (13924)	7/18/2001 7:54:37 AM
From: Clarksterh	Read Replies (3) \| Respond to of 34857

llmarinen - From your statements I am reasonably sure that you aren't familiar with how SnapTrack works. The first clue to how it works is in the name. In an ordinary GPS system there are the following problems: 1) The receiver has to find all of the satellite signals each of which is coded differently. This is a long process due to the fact that the GPS signal is so low in power. SnapTrack, true to their name, avoids this problem by having the cell sites tell the receiver all of the info from the satellites in view except the actual timing inherent in the GPS signals. This makes lock-up very fast. 2) The GPS system inevitably has errors. The satellites are not broadcasting the right ephemeris or the right time or .... . This is the primary cause of location errors up to several 10s of meters. SnapTrack fixes this by having the cell basestation use its knowledge of its own location to figure out the local error in the various satellite signals. It then broadcasts this information to the phones so that they correct the satellite signals. This is called differential GPS and allows it to be much more accurate - it has been a long time since I worked this but my memory says the accuracy is about 10 meters. 3) Obviously this system allows significantly greater privacy since the actual determination of position is done by the handset and only when needed. In contrast, triangulation methods require the basestation network to be continuously figuring out the location of the handset. 4) Due to the fact that the basestations are sending out all of the GPS satellite information except the actual timing inherent in the GPS signal itself, the handset needs only the timing. This is repetative (like the ticking of a clock) and thus easy to track even in a building. Thus a SnapTrack system will lock up anywhere a cell phone works unless the basestation with which it is communicating is underground. Clark