GPS ID Card for students and GPS Accuracy
With times changing and technology advancing there will always be new and innovative ways to do what is right for the students in the classroom. Whatever your view on the issue it doesn’t seem like it will be going away anytime soon. School ID badges aren’t what they used to be. They are no longer just a name, picture and a grade level. With technology expanding, GPS ID Card can now store class schedules, medications and allergies, emergency contact information and even use it as a pre-paid debit card for purchases on campus.
But, when does it go too far? There are some schools now that install Car GPS tracker chips into the cards so they can tell where the students are at all times. GPS technologies will help school authorities and parents to keep track of the school bus, its speed while simultaneously tracking the real time position of students. When students board or alight, their ID cards will be read by the GPS card readers installed on the school bus door. Alerts are sent to the school’s GPS server that automatically sends an update to parents as SMS. The system will be a boon for teachers who are struggling to keep track of hundreds of students. We will charge a fee of Rs 30 every month for the SMS service. Parents will have to pay Rs 60 for the ID card. Now, Parents are happy with this new system and their support has been good. We plan to install CCTV cameras in our school buses soon. Through SMS alerts, parents will know when their kid has boarded the bus or alighted at the stop. Buses caught in traffic can also be detected using this system.
Most people would argue that it is an invasion of privacy, but others believe it is a tactic to keep them safe. If a student goes missing during the day, you could use the GPS tracker to immediately locate them. This could especially come in handy if worst case scenario there is a security breech. Also, many districts budgets and grants are based on attendance, using the tracking chips it would be an easy way to monitor this.
So how accurate is the GPS system? It’s surprisingly difficult to get a good answer to that question. Some sources say a consumer Car tracking GPS is accurate to within 100 feet. Others report it as 50 feet. Manufacturers often give even better numbers, in the vicinity of 20 feet or less. What’s the true story?
First, don’t depend on your receiver to tell you. Although many receivers report something called “Estimated Position Error” or EPE, it is not very accurate. This estimate is based only on satellite geometry and doesn’t consider the various other sources of error. Second, remember that until May 2, 2000, Selective Availability was the most significant source of error. Anything you read that was published before then is probably out-of-date.
The next thing to do is see what the Department of Defense says. After all, they operate the system, so they ought to know its performance, right? But they aren’t as much help as you’d wish. In a typically conservative fashion, they don’t specify total system accuracy, only the part within their direct control, which they call the Signal-in-Space, or SIS. It defines the accuracy of the signals as they radiate from the satellites but leaves out errors introduced as the signals propagate through the atmosphere.
Unfortunately, ever since the demise of Selective Availability, the atmosphere especially the ionosphere—is the most significant source of GPS error. Just as the moon and sun look distorted as they drop low in the sky, signals from GPS satellites are bent as they travel through the atmosphere. They also experience delays that vary depending on the time of day, current solar activity, and moisture level in the air. Manufacturers of GPS receivers use mathematical models to predict and compensate for these errors, but atmospheric conditions are never constant. The Defense Department estimates the accuracy of civilian GPS Tracking Device to be better than 50 feet at least 95 percent of the time, anywhere in the world. This is what’s called the 2drms (twice the distance root-mean-square) accuracy. It is based on statistics. Don’t worry about the math. Just remember that the 2drms number means that over an entire day, a receiver’s accuracy should be better than 50 feet at least 95 percent of the time.
More GPS tracking solutions at http://www.jimilab.com/ .
But, when does it go too far? There are some schools now that install Car GPS tracker chips into the cards so they can tell where the students are at all times. GPS technologies will help school authorities and parents to keep track of the school bus, its speed while simultaneously tracking the real time position of students. When students board or alight, their ID cards will be read by the GPS card readers installed on the school bus door. Alerts are sent to the school’s GPS server that automatically sends an update to parents as SMS. The system will be a boon for teachers who are struggling to keep track of hundreds of students. We will charge a fee of Rs 30 every month for the SMS service. Parents will have to pay Rs 60 for the ID card. Now, Parents are happy with this new system and their support has been good. We plan to install CCTV cameras in our school buses soon. Through SMS alerts, parents will know when their kid has boarded the bus or alighted at the stop. Buses caught in traffic can also be detected using this system.
Most people would argue that it is an invasion of privacy, but others believe it is a tactic to keep them safe. If a student goes missing during the day, you could use the GPS tracker to immediately locate them. This could especially come in handy if worst case scenario there is a security breech. Also, many districts budgets and grants are based on attendance, using the tracking chips it would be an easy way to monitor this.
So how accurate is the GPS system? It’s surprisingly difficult to get a good answer to that question. Some sources say a consumer Car tracking GPS is accurate to within 100 feet. Others report it as 50 feet. Manufacturers often give even better numbers, in the vicinity of 20 feet or less. What’s the true story?
First, don’t depend on your receiver to tell you. Although many receivers report something called “Estimated Position Error” or EPE, it is not very accurate. This estimate is based only on satellite geometry and doesn’t consider the various other sources of error. Second, remember that until May 2, 2000, Selective Availability was the most significant source of error. Anything you read that was published before then is probably out-of-date.
The next thing to do is see what the Department of Defense says. After all, they operate the system, so they ought to know its performance, right? But they aren’t as much help as you’d wish. In a typically conservative fashion, they don’t specify total system accuracy, only the part within their direct control, which they call the Signal-in-Space, or SIS. It defines the accuracy of the signals as they radiate from the satellites but leaves out errors introduced as the signals propagate through the atmosphere.
Unfortunately, ever since the demise of Selective Availability, the atmosphere especially the ionosphere—is the most significant source of GPS error. Just as the moon and sun look distorted as they drop low in the sky, signals from GPS satellites are bent as they travel through the atmosphere. They also experience delays that vary depending on the time of day, current solar activity, and moisture level in the air. Manufacturers of GPS receivers use mathematical models to predict and compensate for these errors, but atmospheric conditions are never constant. The Defense Department estimates the accuracy of civilian GPS Tracking Device to be better than 50 feet at least 95 percent of the time, anywhere in the world. This is what’s called the 2drms (twice the distance root-mean-square) accuracy. It is based on statistics. Don’t worry about the math. Just remember that the 2drms number means that over an entire day, a receiver’s accuracy should be better than 50 feet at least 95 percent of the time.
More GPS tracking solutions at http://www.jimilab.com/ .
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