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The Art of Wireless Sensor Networks – GPS Requirements

Nowadays, the design and development of GPS Personal Tracker for various real-world applications, such as environmental monitoring, health monitoring, industrial process automation, battlefields surveillance, and seism monitoring, has become possible owing to the rapid advances in both of wireless communications and sensor technology. This type of network is cost-effective and appealing to a wide range of mission-critical situations. These two reasons helped them gain significant popularity compared to other types of networks.

A wireless sensor network is a collection of low-powered, physically tiny devices, called sensor nodes, which are capable of sensing the physical environment, collecting and processing sensed data, and communicating with each other in order to accomplish certain common tasks. Furthermore, wireless sensor networks possess a central gathering point, called the sink (or People Tracking Device ), where all the collected data can be stored. The major challenge in the design and development of wireless sensor networks is mainly due to the severe constraints that are imposed on the sensing, storage, processing, and communication features of the sensor nodes. More precisely, the sensor nodes suffer from severely constrained power supplies, which shorten their lifetime and make them unreliable.

It is worth noting that the sensor nodes may become faulty due to improper hardware functioning and/or low battery power (or energy). The latter is very crucial to be considered in the design and implementation of this type of network for their correct operation and longevity. Since their inception in the late 1990s, wireless sensor networks have witnessed significant growth and tremendous development in both academia and industry. A large number of researchers, including computer scientists and engineers, have been interested in solving challenging problems that span all the layers of the protocol stack of sensor networking systems. Several venues, such as journals, conferences, and workshops, have been launched to cover innovative research and practice in this promising and rapidly advancing field. Because of these trends, I thought it would be beneficial to provide our sensor networks community with a comprehensive reference on as much of the findings as possible on a variety of topics in wireless sensor networks. As this area of research is in continuous progress, it does not seem to be a reasonable solution to keep delaying the publication of such reference any more.

GPS Requirements

Accurate knowledge of self-position is paramount to the working of an anchor. Since the un-localized nodes in the network use positioning information of anchors as their reference, errors or inaccuracies in the anchor self-location estimation will propagate throughout the network, rendering the whole localization process erroneous. Therefore, it is essential that an anchor always has accurate knowledge of its position before it disperses its position information in localization beacons. Apparently, the most logical methodology might be the use of GPS Tracking Devices by anchor nodes to determine their own positions. Not surprisingly, this is also the most common approach in most localization schemes. However, for many schemes, depending on the environment, remote deployment fields, etc., the use of Waterproof Tracking Device might not be possible. For example, for many submerged 3D WSNs, submerged anchors determine their positions using surface buoys. Some AUVs for submerged networks use sophisticated trajectory tracking mechanisms to keep track of their positions while beneath ocean surface. These surface buoys act as satellites for deeply submerged, remotely located, inaccessible anchors. Therefore, depending on application and environment, anchor self-localization can incur cost and may compose of complicated mechanical and software mechanisms. A tradeoff needs to be achieved between desired accuracy, system complexity, and economical cost of the anchor hardware.

More information at http://www.jimilab.com/blog/ .

Vehicle GPS Tracking Device and truck hijacking

By 2010, Michael Trei reported that there were devices that could be used by blind people for determining their GPS locations. Suppose a car was carjacked and the police recovered it later. Perhaps one of the passengers was blind and would like to know where she or he was by having something that spoke where they were. The police should look for devices that may have been left in the car such as the “Braille Note GPS”. The investigator should ask any special needs people about any relevant devices that keep track of location. Sometimes children have a cell phone with the family locator feature. If a phone was left on and in a stolen car, it may give the whereabouts to the car’s location.

My opinion is that a truck driver is more likely to be the victim of spoofed Best GPS Tracker signals than other types of people because thieves may wish to target their trucks. The spoofed signals may indicate traffic delays ahead and suggest a diverted path to a deserted road where an ambush may be waiting to kidnap the driver and steal the cargo. The GPS navigation device may be recovered later from the truck and the digital evidence examiner should be aware of spoofing so that he or she is not bewildered by times, dates, and routes that seem illogical.

In 2008, it was reported that there were some researchers at Cornell University and Virginia Tech who built a briefcase—sized device that sent out false signals to spoof GPS signals. Devices took the fake signals to be from the real GPS navigation satellite and put the spoofed coordinates in the Small GPS Tracking Device . Such research complicates GPS forensic investigations because there is now the possibility that signals were spoofed and are not real. However, since such devices only exist in research laboratories and have limited range, it is probably not an issue. If there is a cargo theft investigation, it may be useful to know that such systems exist and data cannot always be trusted. It seems that in optimal conditions with the correct antennas and signal amplifiers, spoofed GPS could be broadcasted for long distances.

There are a variety of devices that use Personal Tracking Device that one can purchase today and have been available since the 1990s. One of them is known as the fishfinder. These devices use GPS and allow boaters the opportunity to mark locations where fish might be. An example of such a device is the Garmin GPSMAP 421 GPS Chart Fishfinder Combo with T/M. The device uses an SD card and routes and locations can be saved. Why might there be an investigation of such a device? The answer is perhaps because someone dumped something at sea such as a body, drugs, or toxic waste. An examination of such a device might show places for divers to look. Another reason to examine such a device might be because of reports of taking treasure from a ship that might belong to an insurance company. Various places where the boat stopped may be checked against wreck sites to see if there was recovery of objects that are property of an insurance company.

GPS device history: multienvironment GPS tracking devices and warrants

In the early twenty-first century, it was possible to see various land-based GPS transponders ‘ sold by companies such as Ness Technologies that had magnetic mounts and allowed first responder agencies to track ambulances in real time. When vehicles are tracked, better 55 dispatching of vehicles can be done in time of emergency. If one has emergency management exercises, vehicle tracking can be used as part of a performance gauge and to see if resources were used efficiently. By 2011, other companies had Personal GPS for Q any environment including air, land, or sea. These types of tracking devices can not only be used for resource allocation but also in criminal or corporate investigations.

An example of one of these new devices that is now available to the consumer, corporate investigator, private investigator, and law enforcement officer is the LandAirSea TracKing® Tracker For Car . This device has been sold from Radio Shack. This device can be used in the air, on the land, or on the water with a variety of vehicles. The device works in temperatures of —15°F to 185°F which is important since airplanes may encounter severe temperature changes in one trip. The device can be used to send out a beacon of its location every second. The receiver can then find out information on the device’s direction, speed, and location. The device uses two AA batteries and can function to durations of 80 h on one set of batteries.

This type of multienvironment device is ideal for investigations where a suspect may use a boat, plane, or car. The device could also be misused by a stalker who tracks an ex-lover and then an investigator may need to do an investigation about the stalker’s mis- use of the Electronic Tracking Device. The amount of uses, misuses, and types of investigations that may result are numerous. If a digital examiner has to examine a GPS navigation device for the airplane, there can be some error because the device is used at a high altitude. Flight location has to be exact since people fly at night, in bad weather, and use instruments when landing at night. There are multitudes of Federal Aviation Administration (FAA) documents online or inline that discuss the Wide Area Augmentation System (WAAS). The WAAS system works with known ground points and GPS satellites through a Ground Uplink System (GUS) and provides an error correction system for the navigation system of the aircraft. The WAAS system can provide as much as 7 m of accuracy to the navigation data of an airplane.

There exist Motorcycle GPS Tracker that transmit a signal and allow someone with a corresponding receiver to obtain real-time location data for that tracking device that is difficult to see since and it can be just a small magnetic item that one sticks under the car. It is possible that the device may also have a small storage device that holds information on where a person drove and it could be examined later. The U.S. Supreme Court at syllabus U.S. v. ]ones decided on January 23, 2012: “The D. C. Circuit reversed, concluding that admission of the evidence obtained by warrantless use of the GPS device violated the Fourth Amendment” [9]. It seems that this may have future implication for collecting data on a variety of mobile GPS devices. It goes to show how the law can change and private investigators and law enforcement people have to keep up with the law.

More information at http://www.jimilab.com/ .

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