Qualcomm Improves Integrated GPS
Network Trinagulation?
Obvious newbie here. If someone has the time could you describe how network triangulation works? It's just out of curiousity.
Thanks
Thanks
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jed_ed said:
Obvious newbie here. If someone has the time could you describe how network triangulation works? It's just out of curiousity.
Thanks
Essentially the carrier and law enforcement (or whoever else is trying to find you) uses whatever towers are in your area to triangulate your position based on the signal your GPS equipped phone gives off.
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um...I don't think your phone has to be gps enabled to do triangulation...
Admittedly, I'm only speaking from my own personal theory on how this works, but I have a guess on how triangulation works. If the tower has something on it that can detect exactly what direction your phone is sending a signal it from, which seem likely, and the tower knows the location of itself, one tower can determine that you're along a certain line from it's position towards where the signal is coming from. Add in a second tower, and where the lines from each tower cross, that's where you are. If you drew out the lines, it would form a triangle - two corners being the towers, and one corner being where you are.
That's totally my personal theory, but it make...
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Admittedly, I'm only speaking from my own personal theory on how this works, but I have a guess on how triangulation works. If the tower has something on it that can detect exactly what direction your phone is sending a signal it from, which seem likely, and the tower knows the location of itself, one tower can determine that you're along a certain line from it's position towards where the signal is coming from. Add in a second tower, and where the lines from each tower cross, that's where you are. If you drew out the lines, it would form a triangle - two corners being the towers, and one corner being where you are.
That's totally my personal theory, but it make...
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Thats close to how I have heard it explaned only it takes 3 towers. and GPS does work with triangulation, it just gets signal from satalies and not from cell towers.
With 3 you only need to know the distance from each. Which can easaly be determined with little more than a really fast stop watch.
With 3 you only need to know the distance from each. Which can easaly be determined with little more than a really fast stop watch.
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Tri. is the way they find you if you don't have GPS... if you have a GPS enabled phone... you can be located near instantly with satellite... 😎
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You're not located by satellite. The satellite gives off the gps signal that the phone uses to determine a location(probably lat/long). The phone uses the wireless network to transmit the location to E911. Most gps units use 3 satellite signals to calculate the most accurate location, not sure if this is true for phones. I believe the triangulation is by having 3 different towers notice the phone and relative signal to determine an area that the phone COULD be.
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So what you're saying is... is that they use satellite... way to try and correct me... 😉
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insidescooppp said:
So what you're saying is... is that they use satellite... way to try and correct me... 😉
Actually, triangulation isn't even used in GPS. Triangulation is when you have a bunch of receivers listening to a single source. Compare the signal strengths and you can find out where the source is. The GPS satellites have no idea where you are. They can not find you. They don't have receivers, they just spit out a signal. GPS uses something similar, called trilateration, where you have one receiver tuned into several transmitters. If you know where the transmitters are, you can find out where the receiver is. So no, they don't find you with GPS satellites. You find yourself. Rich...
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PaulRivers said:
um...I don't think your phone has to be gps enabled to do triangulation...
Admittedly, I'm only speaking from my own personal theory on how this works, but I have a guess on how triangulation works.
Um, if you're working from a theory, then I guess it's not polite to attempt to make someone feel stupid, is it?
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Triangulation is the basis for nearly all radio-based position-location technologies.
The basic idea starts with measuring the distance of what you want to locate (the phone) from three points with known locations (three towers, or three GPS satellites).
The distance is measured by precisely measuring the amount of time the signal takes to travel in one direction, or make a round-trip.
You need to measure from three points because:
- If you only had one point, you'd know the distance, but not the direction, so the phone could be anywhere along a circular path surrounding that tower (or satellite).
- If you only had two known points, you'd know the phone was where the two circular paths intersected, but the problem is they inte...
(continues)
The basic idea starts with measuring the distance of what you want to locate (the phone) from three points with known locations (three towers, or three GPS satellites).
The distance is measured by precisely measuring the amount of time the signal takes to travel in one direction, or make a round-trip.
You need to measure from three points because:
- If you only had one point, you'd know the distance, but not the direction, so the phone could be anywhere along a circular path surrounding that tower (or satellite).
- If you only had two known points, you'd know the phone was where the two circular paths intersected, but the problem is they inte...
(continues)
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Rich Brome said:
GSM networks rely almost exclusively on an advanced version of tower triangulation.
Out of curiousity, do GSM carriers still have to have gps equipped phones for E911 or does the FCC allow their advanced tower triangulation as sufficient for E911?
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Most U.S. GSM carriers rely on tower (network) triangulation. It doesn't require GPS (or anything special at all) in the phone.
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I understand that. My question is in regards to FCC requirements. Are GSM carriers required to use GPS or is the tower method accepted by the FCC?
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Ah - sorry.
The FCC allows either method.
Regardless of whether GPS is used, the FCC has two sets of rules:
The first set is for a handset-based method. This means there is special technology in the phone to enable/assist position location. This generally means A-GPS, but I don't think the FCC says that specifically.
The second set of rules is for a technology that's network-based, where the network can find any phone without special technology in the phone at all.
The reason for the two sets of rules is that handset-based technologies generally can be more accurate, and so the FCC in fact requires more accuracy in that case. Also, since handset-based technologies require special phones, there had to be rules for how quickly t...
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The FCC allows either method.
Regardless of whether GPS is used, the FCC has two sets of rules:
The first set is for a handset-based method. This means there is special technology in the phone to enable/assist position location. This generally means A-GPS, but I don't think the FCC says that specifically.
The second set of rules is for a technology that's network-based, where the network can find any phone without special technology in the phone at all.
The reason for the two sets of rules is that handset-based technologies generally can be more accurate, and so the FCC in fact requires more accuracy in that case. Also, since handset-based technologies require special phones, there had to be rules for how quickly t...
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http://www.snaptrack.com/ »
Everything is explained there in detail.
Synchronize your base station pilot signals using GPS and they can replace one or more of three faint GPS sat signals with stronger cell network signals. Suddenly, you have GPS that reliably works indoors.
Check your CDMA phone manual. There most likely is an icon on your display (plus sign with a circle at the center) that indicats you have GPS enabled.
With Snaptrack, your phone only sends out your location when you request it. Your phone calculates your position and sends it to a server at the provider.
Without Snaptrack, your provider uses the network to discern your location and there isn't a damn thing you can do to stop it except turn the phone of...
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Everything is explained there in detail.
Synchronize your base station pilot signals using GPS and they can replace one or more of three faint GPS sat signals with stronger cell network signals. Suddenly, you have GPS that reliably works indoors.
Check your CDMA phone manual. There most likely is an icon on your display (plus sign with a circle at the center) that indicats you have GPS enabled.
With Snaptrack, your phone only sends out your location when you request it. Your phone calculates your position and sends it to a server at the provider.
Without Snaptrack, your provider uses the network to discern your location and there isn't a damn thing you can do to stop it except turn the phone of...
(continues)
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This forum is closed.
