Ryder
Having a senior moment
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Well it seems as though we keep getting questions about tracking devices from people so I thought I would put a little post together to answer some of the more frequently asked questions.
Most people know the difference between GPS, GPRS and GSM but since this is a beginners guide after all, perhaps it is best to start out by differenciating between them.
GPS: The global positioning system, facilitated by a network of around 30 satellites operates in the following way. Each satellite contains a clock... the most recently launched satellites contain rubidium clocks and by using these clocks and by talking to eachother the satellites are able to produce a steady stream of numbers and transmit them toward the Earth's surface.
The GPS receiver listens out for the stream of numbers and by measuring the time difference between different streams is able to triangulate a position with some degree of accuracy.
As with all technology, there is a fly in the ointment: Radio signals, as any school boy physics student will tell you, speed up or slow down according to the environment they are passing through. Hence, as they pass through the atmosphere a degree of inaccuracy is introduced to the receiver's interpretation of its current location. The answer came by way of an ingenious system called DGPS (Differential GPS). This records the actual lat/lon for a known point. Then the receiver is able to query what the variation is between the known correct position and the decoded position and apply that differentiation to the final position on the local gps receiver... if all that sounds a bit involved then put simply... DGPS is ****loads more accurate than GPS alone.
Modern receivers are capable of analysing up to 64 incoming data streams - basically the more channels the better when you are looking into any kind of GPS device... be it tracker or simple navigation.
OK so having achieved a signal and decoded it to provide your current location, you now need a carrier to relay that information back to a server, whether that is at a monitoring station or a web server allowing your wife to determine whether you are seeing a bit on the side!
Most common is to use GPRS, (General Packet Radio System), which is the technology used by GSM mobile phones to access t'interweb. Because this is an "always on" connection, positions can flow quickly and simply - however coverage is patchy on some more remote areas (our tests have shown that desert areas can pose problems although even in Algeria we were fine in built up areas. If you need reliable coverage for literally anywhere then you should be thinking about satellite phones linked to your tracker... not cheap but more reliable in these conditions.)
On a slightly aside note: though related... remember that any use of GPS is illegal in Algeria and they will not look kindly on finding it in your vehicle... so ensure any tracking device is well hidden and can be disabled easily when approaching the border.
Over the last year or so of reading posts about tracking devices - people seem to fall into one of two camps. Either they think that trackers are great or they think that they can achieve a better result for less money using a baked bean can and a roll of gaffer tape.
Mobile phone in the glovebox method
Anyone who seriouisly thinks that this is going to get them their vehicle back is kidding themselves.
The GPS system embedded in mobile phones is of a very low and hideously inaccurate variety. Positions are vague in the extreme.. in fact when I look at my own blackberry I am lucky to get a position closer than 200 yards of my current location. That's ok if I am walking I guess... but searching every location withina 200 yard radius that's an area of over 1200 square yards or just under 3/4 of a square mile for a vehicle would be like searching for a needle in a haystack. It would also be a nasty time to find out that the bloke on the forum you were reading about actually got it wrong. Additionally the power of the receiver is very small. Using fewer channels than a tracker, cheaper components than a decent tracker and having a lower reception level all combine to make sure that the phone is the ****tiest solution of all. (Except the bean can idea!)
How to choose a tracker
Actually choosing the tracking system is not all that difficult once you work out what you want the system to achieve. The main source of confusion comes from the fact that so many companies offer tracking devices, and many sales reps are unaware of the device's limitations or abilities. Minor Planet, once the market leader in tracking devices suffered from this problem to the extent that it lost them a great many sales. Reps were continually promising the earth and the installation engineers knew that some of those promises could simply not be fulfilled!
Lets start by saying that as a rule... if it is not manufactured in Europe or Ireland you should not consider buying it for anything important. Chinese devices are simply not reliable; and getting coherent support can be difficult. That's bad enough when it is a simple tracking device but it is bloody awful if you are using the device as a full blown vehicle management system and you have satellite locked yourself out of the vehicle and can't get in to reset the system.
Looking at price: a decent tracking device will be costing in the region of £150-£200. This will include a fitting kit and covert antenna for both GSM and GPS reception.
Typically you should be looking for combinations of the following services available without necessitating any further hardware:
i. Single position reporting to a web site or your mobile phone on request
ii. Continuous position reporting to a web site so that you can follow your vehicle on screen or from your mobile phone.
iii. Geo-Locking - ie setting the tracker to notify you if the vehicle is moved more than 100 meters (or a preset distance) from where it is now.
iv. Geo Fencing - the ability to set areas that will result in a message being sent to your phone or the web site... useful for congestion charge reminders on a personal vehicle...
Many systems will offer more but these are pretty much the basics.
On a more advanced system: say a vehicle management system rather than a simple tracker:
i. Everything you would expect from the basic system plus some of the following
ii. ability to activate central locking from mobile phone
iv. Ability to deactivate ignition or limit engine output
v. active monitoring of various conditions
Of course these will come with extra fees attached but a top notch system will allow for these to be added in later should the need arise.
Finally... and forgive me for posting such a long and rambling roll of information but,
If you want something specific from your system, then search around until you find a company that will give it to you. In the tracking industry, almost more than any other, people are fond of telling you what you can have and not listening to what you want from the system. Stand your ground... if you want reports insist on them... if you want a monitoring station then don't settle for second best and ask for a tour of the monitoring station before you invest, make sure you get monthly or annual tests and if possible take a look at a demonstration system first.
I think I have covered most of the basic points but am quite happy to answer any further queries.
I do have ten years' experience in the industry both in R&D and programming of these systems and the points made in this post, while lin part my own opinion, are based on solid and reliable fact.
If you are searching for tracking answers I hope this went some way to helping.
cheers
Ryder
Most people know the difference between GPS, GPRS and GSM but since this is a beginners guide after all, perhaps it is best to start out by differenciating between them.
GPS: The global positioning system, facilitated by a network of around 30 satellites operates in the following way. Each satellite contains a clock... the most recently launched satellites contain rubidium clocks and by using these clocks and by talking to eachother the satellites are able to produce a steady stream of numbers and transmit them toward the Earth's surface.
The GPS receiver listens out for the stream of numbers and by measuring the time difference between different streams is able to triangulate a position with some degree of accuracy.
As with all technology, there is a fly in the ointment: Radio signals, as any school boy physics student will tell you, speed up or slow down according to the environment they are passing through. Hence, as they pass through the atmosphere a degree of inaccuracy is introduced to the receiver's interpretation of its current location. The answer came by way of an ingenious system called DGPS (Differential GPS). This records the actual lat/lon for a known point. Then the receiver is able to query what the variation is between the known correct position and the decoded position and apply that differentiation to the final position on the local gps receiver... if all that sounds a bit involved then put simply... DGPS is ****loads more accurate than GPS alone.
Modern receivers are capable of analysing up to 64 incoming data streams - basically the more channels the better when you are looking into any kind of GPS device... be it tracker or simple navigation.
OK so having achieved a signal and decoded it to provide your current location, you now need a carrier to relay that information back to a server, whether that is at a monitoring station or a web server allowing your wife to determine whether you are seeing a bit on the side!
Most common is to use GPRS, (General Packet Radio System), which is the technology used by GSM mobile phones to access t'interweb. Because this is an "always on" connection, positions can flow quickly and simply - however coverage is patchy on some more remote areas (our tests have shown that desert areas can pose problems although even in Algeria we were fine in built up areas. If you need reliable coverage for literally anywhere then you should be thinking about satellite phones linked to your tracker... not cheap but more reliable in these conditions.)
On a slightly aside note: though related... remember that any use of GPS is illegal in Algeria and they will not look kindly on finding it in your vehicle... so ensure any tracking device is well hidden and can be disabled easily when approaching the border.
Over the last year or so of reading posts about tracking devices - people seem to fall into one of two camps. Either they think that trackers are great or they think that they can achieve a better result for less money using a baked bean can and a roll of gaffer tape.
Mobile phone in the glovebox method
Anyone who seriouisly thinks that this is going to get them their vehicle back is kidding themselves.
The GPS system embedded in mobile phones is of a very low and hideously inaccurate variety. Positions are vague in the extreme.. in fact when I look at my own blackberry I am lucky to get a position closer than 200 yards of my current location. That's ok if I am walking I guess... but searching every location withina 200 yard radius that's an area of over 1200 square yards or just under 3/4 of a square mile for a vehicle would be like searching for a needle in a haystack. It would also be a nasty time to find out that the bloke on the forum you were reading about actually got it wrong. Additionally the power of the receiver is very small. Using fewer channels than a tracker, cheaper components than a decent tracker and having a lower reception level all combine to make sure that the phone is the ****tiest solution of all. (Except the bean can idea!)
How to choose a tracker
Actually choosing the tracking system is not all that difficult once you work out what you want the system to achieve. The main source of confusion comes from the fact that so many companies offer tracking devices, and many sales reps are unaware of the device's limitations or abilities. Minor Planet, once the market leader in tracking devices suffered from this problem to the extent that it lost them a great many sales. Reps were continually promising the earth and the installation engineers knew that some of those promises could simply not be fulfilled!
Lets start by saying that as a rule... if it is not manufactured in Europe or Ireland you should not consider buying it for anything important. Chinese devices are simply not reliable; and getting coherent support can be difficult. That's bad enough when it is a simple tracking device but it is bloody awful if you are using the device as a full blown vehicle management system and you have satellite locked yourself out of the vehicle and can't get in to reset the system.
Looking at price: a decent tracking device will be costing in the region of £150-£200. This will include a fitting kit and covert antenna for both GSM and GPS reception.
Typically you should be looking for combinations of the following services available without necessitating any further hardware:
i. Single position reporting to a web site or your mobile phone on request
ii. Continuous position reporting to a web site so that you can follow your vehicle on screen or from your mobile phone.
iii. Geo-Locking - ie setting the tracker to notify you if the vehicle is moved more than 100 meters (or a preset distance) from where it is now.
iv. Geo Fencing - the ability to set areas that will result in a message being sent to your phone or the web site... useful for congestion charge reminders on a personal vehicle...
Many systems will offer more but these are pretty much the basics.
On a more advanced system: say a vehicle management system rather than a simple tracker:
i. Everything you would expect from the basic system plus some of the following
ii. ability to activate central locking from mobile phone
iv. Ability to deactivate ignition or limit engine output
v. active monitoring of various conditions
Of course these will come with extra fees attached but a top notch system will allow for these to be added in later should the need arise.
Finally... and forgive me for posting such a long and rambling roll of information but,
If you want something specific from your system, then search around until you find a company that will give it to you. In the tracking industry, almost more than any other, people are fond of telling you what you can have and not listening to what you want from the system. Stand your ground... if you want reports insist on them... if you want a monitoring station then don't settle for second best and ask for a tour of the monitoring station before you invest, make sure you get monthly or annual tests and if possible take a look at a demonstration system first.
I think I have covered most of the basic points but am quite happy to answer any further queries.
I do have ten years' experience in the industry both in R&D and programming of these systems and the points made in this post, while lin part my own opinion, are based on solid and reliable fact.
If you are searching for tracking answers I hope this went some way to helping.
cheers
Ryder
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