CA2507585A1 - Reduced bandwidth communications in remote location tracking applications - Google Patents
Reduced bandwidth communications in remote location tracking applications Download PDFInfo
- Publication number
- CA2507585A1 CA2507585A1 CA 2507585 CA2507585A CA2507585A1 CA 2507585 A1 CA2507585 A1 CA 2507585A1 CA 2507585 CA2507585 CA 2507585 CA 2507585 A CA2507585 A CA 2507585A CA 2507585 A1 CA2507585 A1 CA 2507585A1
- Authority
- CA
- Canada
- Prior art keywords
- data
- tracker device
- tracker
- coordinates
- data packet
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Abandoned
Links
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
- G01S19/00—Satellite radio beacon positioning systems; Determining position, velocity or attitude using signals transmitted by such systems
- G01S19/01—Satellite radio beacon positioning systems transmitting time-stamped messages, e.g. GPS [Global Positioning System], GLONASS [Global Orbiting Navigation Satellite System] or GALILEO
- G01S19/03—Cooperating elements; Interaction or communication between different cooperating elements or between cooperating elements and receivers
- G01S19/09—Cooperating elements; Interaction or communication between different cooperating elements or between cooperating elements and receivers providing processing capability normally carried out by the receiver
Landscapes
- Engineering & Computer Science (AREA)
- Radar, Positioning & Navigation (AREA)
- Remote Sensing (AREA)
- Computer Networks & Wireless Communication (AREA)
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Position Fixing By Use Of Radio Waves (AREA)
Description
306 359 6956 Furman 1 Kalio Furman & Kallio 03'51:01 p.m. Q5-17-2005 6127 REDUCED BANDWIDTH COMMUNICATIONS IN REMOTE LOCATION
TRACKING APPLICATIONS
s This invention is in the field of remote position tracking equipment and more specifically in the field of GPS enabled devices capable of transmitting data to a remote location.
BACxGROUND
to The Global Positioning System (CPS) of medium-earth (MEO) orbit satellites allows people to accurately pinpoint their position using a GPS radio frequency receiving device ("GPS module") that uses triangulation to determine it's position by precisely measuring the time delay of coded radio frequency signals from a number of GPS
satellites ~ 5 simultaneously in view of the GPS module. This has allowed people to easily determine the locations of themselves and objects using a GPS device.
By combining wireless transmitting capabilities and a control module with a GPS
module, devices have been constructed that allow position coordinates determined by the 2o GPS module to be transmitted to a remote location, so that the position of the device can be determined or even tracked over time from a remote location. In well populated areas where there is readily available access to wireless communication infrastructures such as cellular telephone networks with antennas mounted on terrestrial towers or other 306 359 6956 Furman 1 Kalio F~xman & Kallio 03:51:30 p.m 05-17-2005 7127 - Pagc 2 -structures, the wireless transmission can be accomplished quickly and relatively inexpensively per transmission. The benefit of using locally accessible terrestrial wireless communication infrastructures is that it is relatively easy and inexpensive to send data from the GPS device over the wireless communication infrastructure.
T'he result is that these devices send packets of data often, and these data packets often include a number of different data values such as the coordinates of a vehicles location, direction of travel, velocity, etc. in addition to basic location coordinates. Each of these data packets is then used to determine the position, direction and other position information related to the traveling vehicle.
to While this system may be practicable in areas with ready access to one or more terrestrial wireless communication infrastructures, when tracking devices are to be used in remote locations the available terrestrial and satellite-based wireless communication infrastructures can have much higher data transfer costs or may not be as accessible as in other areas. Many times it is not possible to transmit a remote device's location, position by position, at short intervals and even if it is possible the data transfer costs can be significant.
In more remote locations and especially northern locations, substantial wireless 2o communication coverage is usually only available using a low earth orbit (LEO) satellite communication system. In order to transmit to a communication satellite, the 306 359 6956 Forman 1 Kalio Fuman 8 Kallio 03:52:01 p.m 05-17-2005 8127 _ Page 3 .
communication satellite must be visible to the transmitting device. Commercial communication systems employing LEO satellites in circular orbit generally have orbital periods on the order of approximately 100 minutes. Therefore, for an observer on the ground, LEO satellites come in and out of view at a relatively rapid rate in comparison to medium-earth obit satellites with orbital periods of 6-12 hours, and geostationary earth orbit satellites, with a period of exactly one day and appear stationary in the sky to an observer on earth. This means that the LEO satellites will come in and out of view of a particular point on the earth at a fairly rapid rate. Constellations of LEO
satellites need a relatively high number of satellites in order to provide coverage that will completely cover the earth at any time. Nearly all LEO communication satellite constellations do not provide 100 earth coverage. Most systems are designed with the best coverage being focused at nud-latitudes. Therefore, there will not always be constant, uninterrupted communication abilities over the satellite network, a problem which becomes a significant constraint in remote locations, notably high northern and southern latitudes.
Some satellite communication systems have satellite visibility gaps of 15 minutes or longer where no service is available to users. Additionally, because satellite communication relies upon line of sight with the transmitting device, in areas with limited view of the sky such as gorges or other areas, this time is extended even further 2o because the transmitting device would have to wait until a satellite is in view of its limited sight; in very sheltered locations, satellites have to pass directly above the 306 359 6956 Forman 1 Kalia Furman 8 Kallio 03.52:34 p.m. 05-17-2005 9127 transmitting device and satellite can communicate, thus severely restricting the minutes per day of satellite communication capability.
Not only may there be limited periods of time in which data can be transmitted from a device, there can also be significant costs associated with the bandwidth of messages transmitted over the system. In more populous regions with more options for wireless communication and more accessibility to these systems, bandwidth and the number of transmissions might not be a significant cost, both in resource utilization of the wireless communication system and actual billing cost. This may be different in remote locations where battery power is heavily utilized and power requirements of the transmitting device have to be minimized. In more remote locations it is often just not suitable to send location data position by position in separate transmissions either because the satellites are not in range frequently enough to make repeated transmissions over relatively small time intervals feasible. Even in areas with readily accessible wireless communication ~ s infrastructures, it might be simply desirable to reduce ttee bandwidth costs and number of transmissions of a transmission device.
SUMMARY OF ~ INVENTION
306 359 6956 Furrnan l Kalio Forman & Kallio 03:53:03 p m. 05-17-2005 10 !27 It is an object of the present invention to address disadvantages in the prior art.
A tracker device comprising: a GPS module; a GPS antenna; a transmitter module; a transmitter antenna; and a control module, is disclosed. The tracker device is a remote device to be carried with a person, a vehicle or other object to be tracked from a remote location. The tracker device can use the GPS module to dctcrrrtine its position and forward location data to a remote location so that either operators at a remote location can track the movements of the tracker device, or the information can be forwarded to another party using a remote device, informing a user of the remote device where the lo tracker device is located.
In one embodiment of the invention, the tracker device is operative to transmit data packets through a satellite communication system back to a central server located at a remote location. At the central server, the data packet is parsed and the location data contained in the data packet is processed to determine a history of previous locations of the tracker device. This location data is stored at the central server and provided to a remote device so that a subscriber can track the movements of a specific tracker device.
Rather than the tracker device transmitting a single set of location coordinates and other 2o associated position data at relatively short intervals to the central server, the tracker device assembles a data packet containing at least one time stamp and a number of 306 359 6956 Forman 1 Kalio Furman 8 Kallio 03:53:33 p.m. 05-17-2005 11 I27 - Page b -coordinates indicating the location of the tracker device over a period of time. Typically, the time stamp will coincide with the time the tracker device was at the first set of coordinates. Each additional set of coordinates assembled into the data packet will then be timed a predetermined interval of time after the preceding set of coordinates. When the data field is filled with the desired number of sets of coordinates the tracker device will finish assembling the data packet and transmit it to the central server.
The central server receiving the data packet will be able to parse it and getting the time stamp and knowing the approximate time intervals will be able to determine past t0 locations of the tracker device at approximate times. Because a number of coordinates separated by relatively small time intervals are transmitted together in the same data packet, the central server can use the different locations and their approximate times to determine a wide range of other values such as approximate direction of the tracker device, approximate velocity of the tracker device, and other information related to the is movement of the tracker device.
The central server can build a relatively complete history of the past locations of the tracker device with substantially fewer data packets having to be transmitted.
This is especially beneficial when the overhead costs for the wireless infrastructure are relatively 2o high or the resources available are limited, however, it could also be used to simply reduce the amount of transmissions required by the tracker device.
306 359 6956 Forman 1 Kalio Furman 8 Kallio 03v 54x05 p m. 05-17-2005 12 !27 DESCRIPTION OF THE DRAWI1~1GS:
While the invention is claimed in the concluding portions hereof, preferred embodiments are provided in the accompanying detailed description which may be best understood in conjunction with the accompanying diagrams where like parts in each of the several diagrams are labeled with like numbers, and where:
t0 Fig. 1 is a schematic diagram of a tracker device, in accordance with the present invention;
Fig. 2 is a schematic diagram of a personnel tracking and monitoring system incorporating the tracker device of Fig. 1, in accordance with the present invention;
Fig. 3 is a schematic diagram of a data packet containing location data, in accordance with the present invention; and 2o Fig. 4 is a method of assembling a data packet, in accordance with the present invention-30fi 359 6956 Furman 1 Kalio Furman & Kallio 03:54x28 p.m 05-17-2005 13/27 DETAILED DESCRIPTION OF THE ILLUSTRATED EMBODIMENTS
Fig. 1 schematically illustrates a tracker device 10 comprising: a GPS module 12; a GPS
antenna 13; a transmitter module 14; a transmitter antenna 15; a control module 16 and an input/output interface module 18. The tracker device 10 is a remote device that can be transported with a person or object. The tracker device 10 can determine its position and transmit this position data to a remote location, allowing the position of a tracker device to 10 to be determined at the remote location.
The GPS module 12 is a GPS receiver operative to receive global positioning satellite signals using the GPS antenna 13 and process these signals into position and other data.
t5 The transmitter module 14 is operative to transmit data packets from the tracker device 10. Although this transmitter 14 could be operative to transmit data over any wireless infrastructure system such as a terrestrial cellular telephone system or some other system, in one embodiment of the invention it is contemplated that the transmitter module 14 would be a satellite transmitter operative to transmit data via satellite such as the 20 OrbcommTT'' satellite system.
306 359 6956 Forman 1 Kalio Forman & Kallio 03-54'55 p.m. 05-17-2005 14 !27 The control module 16 controls the operation of the tracker device IO and is in communication with the GPS module 12, transmitting module 14 and I/O module 1$.
The control module 1b receives location data from the GPS module 12 and tin store this data. Additionally, the control module 16 is operative to assemble and format data packets at determined intervals and transmits these assembled data packets using the transmitting module 14 over the wireless infrastructure. In addition, the control module 16 controls the general operation of the tracker device 10 such as activating and deactivating the GPS module 12 and controlling the mode of operation of the tracker device 10 (i.e. receiver on, unit on low-power sleep, etc.).
l0 Optionally, the programming of the control module 16 can be altered remotely.
The transmitter/reeeiver module 14 can receive data that can alter the progamming of the control module 1b allowing the programming of the control module 16 to be altered remotely. Parameters such as the interval between times of transmission of data packets containing location data by the tracks device 10 can be altered remotely without requiring the tracker device 10 to be taken in for servicing or an on-site visit made for servicing. Also, the programming of the tracker device 10 can be altered remotely without requiring the operator of the tracker device 10 to have to make any changes to the tracker device 10 by him or herself.
306 359 6856 Forman 1 Katio Forman 8 Kallio 03:55:25 p.m. 05-17-2005 15127 The 1l0 interface module 18 can be attached to sensor inputs, outputs and/or other interfaces to be connected to the tracker device 10. Any inputs can be monitored by the control computer 16 and the control computer 16 can implement a pre-programmed action when certain conditions are met. The 1/0 interface module 18 can also allow the s attachment of a number of outputs that allows the control computer 1b to provide outputs when pre-determined conditions are met. For example, a temperature sensor could be connected to the 1/O interface module 18 to monitor the temperature of the contents of a container the tracker device 10 is attached to. If the temperature of the contents of the container drops below a specified level or cacceeds a specified level, the control computer 16 can transmit a message back to the central server 110 to alert people to the detected condition and provide an output through the 1l0 interface module I8 that will activate a backup environmental control.
The I/O interface module 18 can also be used to control an ezternal device remotely through a serial connection.
Fig. 2 is a schematic illustration of an overall system using the tracker devices 10 where the wireless infrastructure is a satellite communication system. The system comprises:
tracker devices 10; global p~itioning satellites 50; communication satellites 100; a 2o gateway station 105; a data network 107; a central server 110; and a remote terminal 1 Z0.
The tracker device 10 determines position data using the GPS satellites 50 and transmits 306 359 6956 Furman I Kalio Furman 8 Kallio 03:55:57 p m05-17-2005 16 !27 - Page l 1 -location data based on this position data to the central server 110, allowing a person using the remote tetrainal 120 to access this location data.
In operation, each of the tracker devices 10 will receive signals from the global positioning satellites 50 and from these signals determine position data. Each tracker device 10 log9 this position data and at intervals the tracker device 10 generates a data packet containing location data and transmits the data packet using the transmitter antenna 15 to the communication satellites 100.
a0 The communication satellites 100 are typically low-earth orbit satellites.
This allows data transmitted to the communication satellites 100 to be transmitted with lower powered transmitters, but because of the orbits of the communication satellites 100, the satellites 100 are not always in communication with the tracker devices 10.
This is especially true in remote locations. The tracker devices 10 transmit location data to the t5 communication satellites 100 using a store and forward method. If a communication satellite I00 is not in view, the tracker devices 10 store the data packets in memory anti! a communication satellite 100 comes into communication with the tracker device 10. Once the communication satellite I00 has come into communication with tracker device 10 the tracker device IO will forward or transmit the data packet to the communication satellite 20 100.
306 359 6956 Forman 1 Kalio Forman 8 Kallio 03:56x27 p.m 05-17-2005 17 l27 Once a data packet has been transfured to a communication satellite 100, the communication satellite 100 transmits the data packet to a gateway station 105. Again, the communication satellite 100, because of its orbit, is not always in communication with a gateway station 105. The data packet is typically transmitted to the gateway station 105 in a stare and forward method, whue the communication satellite 100 stores the data packet until the communication satellite 100 is in communication with a gateway station 105 and then transmits the data packet to the gateway station 105.
Generally, although not necessarily, the tracker device 10 can be operative to implement t0 an acknowledge-or-retransmit algorithm to ensure successful transmission of the data packets. When a data packet is received by the gateway station 105, the gateway station 105 can transmit an acknowledgement of receipt back through the communication satellites 100 to the tracker device 10 which is operative to receive incoming data packets. The tracker device 10 will wait after transmitting a data package for this acamowledgment of receipt by the gateway station 105. If no acknowledgment of receipt is received by the tracker device 10, the tracker device 10 will attempt to retransmit the data packet and can, continue to do so until an acknowledgment of receipt by the gateway station 105 is received by the tracker device 10.
2o From the gateway station 105, the data packet is transmitted over a data network 107 to a central saver 110. The central server 110 logs the data packets and identifies them in 306 359 6956 Furman 1 Kalio Furman 8 Kallio 03:56:59 p.m. 05-17-2005 18127 respect of which tracker device 10 transmitted the data packet. The central server 110 can then store the different locations of each tracker device 10 at different times and build a history of locations the tracker device 10 has been located over time.
Although Fig. 2 illustrates the system using a low earth orbit satellite system as the wireless infrastructure being used to transmit data packets from the tracker devices 10 to the central server 110, it is contemplated that other suitable wireless communication systems capable of transmitting data from the tracker devices 10 to the ventral server 110 could be used. For example, the tracker devices 10 and central server 110 could be communicating through a cell phone wireless network or other such system.
The remote device 120 can be a cell phone, pager, fax or other device where an operator of the remote device 120 can be quickly notified of the position of the tracker device 10.
Alternatively, the remote device 120 could be a personal computer, PDA or other device ~5 in communication with the central server 110 over a TCP/IP connection or wireless network and the location information could be forwarded to the remote device 120 in an email or through a specific program running on the remote device 120. The central server 110 can communicate a last position of the tracker device 10 to the remote device 120 or a number of past locations. 1n one embodiment, the remote device 120 has a map 2o client that can display the locations of a tracker device 10 overlaid on a map displayed on the remote device 120.
306 359 6956 Forman 1 Kalio Ftxman & Kaliio 03:57'30 p.m. 05-17-2005 19127 Pad t4 -While the use of a remote device 120 is discussed herein, it will also he understood that the general method of communication comprising assembling a number of interval location data into a single packet and communication thereof for parsing and logging in a central server is also contemplated to be a broad embodiment of the method which is understood to be within the scope of the presant disclosure.
Fig. 3 is a schematic illustration of a data packet 200 in accordance with the present invention. The data packet 200 comprises: a packet header 205; a data field 20'1 and a to packet trailer 209.
The packet header 205 is used to transmit the data packet 200 through the system as is well known in the art. The packet header 205 typically contains a source address, a destination address, and other information such as the length of the data packet 200, that ~5 enable the transmission of the data packet 200 to the central server 110. A
person skilled in the art will appreciate the packet header 205 can vary depending upon the type of transmission protocols used and the wireless infrastruetux~e, etc.
Additionally, additional headers will likely be added to the data packet 200 as it is transmitted through the system to the central server 110.
TRACKING APPLICATIONS
s This invention is in the field of remote position tracking equipment and more specifically in the field of GPS enabled devices capable of transmitting data to a remote location.
BACxGROUND
to The Global Positioning System (CPS) of medium-earth (MEO) orbit satellites allows people to accurately pinpoint their position using a GPS radio frequency receiving device ("GPS module") that uses triangulation to determine it's position by precisely measuring the time delay of coded radio frequency signals from a number of GPS
satellites ~ 5 simultaneously in view of the GPS module. This has allowed people to easily determine the locations of themselves and objects using a GPS device.
By combining wireless transmitting capabilities and a control module with a GPS
module, devices have been constructed that allow position coordinates determined by the 2o GPS module to be transmitted to a remote location, so that the position of the device can be determined or even tracked over time from a remote location. In well populated areas where there is readily available access to wireless communication infrastructures such as cellular telephone networks with antennas mounted on terrestrial towers or other 306 359 6956 Furman 1 Kalio F~xman & Kallio 03:51:30 p.m 05-17-2005 7127 - Pagc 2 -structures, the wireless transmission can be accomplished quickly and relatively inexpensively per transmission. The benefit of using locally accessible terrestrial wireless communication infrastructures is that it is relatively easy and inexpensive to send data from the GPS device over the wireless communication infrastructure.
T'he result is that these devices send packets of data often, and these data packets often include a number of different data values such as the coordinates of a vehicles location, direction of travel, velocity, etc. in addition to basic location coordinates. Each of these data packets is then used to determine the position, direction and other position information related to the traveling vehicle.
to While this system may be practicable in areas with ready access to one or more terrestrial wireless communication infrastructures, when tracking devices are to be used in remote locations the available terrestrial and satellite-based wireless communication infrastructures can have much higher data transfer costs or may not be as accessible as in other areas. Many times it is not possible to transmit a remote device's location, position by position, at short intervals and even if it is possible the data transfer costs can be significant.
In more remote locations and especially northern locations, substantial wireless 2o communication coverage is usually only available using a low earth orbit (LEO) satellite communication system. In order to transmit to a communication satellite, the 306 359 6956 Forman 1 Kalio Fuman 8 Kallio 03:52:01 p.m 05-17-2005 8127 _ Page 3 .
communication satellite must be visible to the transmitting device. Commercial communication systems employing LEO satellites in circular orbit generally have orbital periods on the order of approximately 100 minutes. Therefore, for an observer on the ground, LEO satellites come in and out of view at a relatively rapid rate in comparison to medium-earth obit satellites with orbital periods of 6-12 hours, and geostationary earth orbit satellites, with a period of exactly one day and appear stationary in the sky to an observer on earth. This means that the LEO satellites will come in and out of view of a particular point on the earth at a fairly rapid rate. Constellations of LEO
satellites need a relatively high number of satellites in order to provide coverage that will completely cover the earth at any time. Nearly all LEO communication satellite constellations do not provide 100 earth coverage. Most systems are designed with the best coverage being focused at nud-latitudes. Therefore, there will not always be constant, uninterrupted communication abilities over the satellite network, a problem which becomes a significant constraint in remote locations, notably high northern and southern latitudes.
Some satellite communication systems have satellite visibility gaps of 15 minutes or longer where no service is available to users. Additionally, because satellite communication relies upon line of sight with the transmitting device, in areas with limited view of the sky such as gorges or other areas, this time is extended even further 2o because the transmitting device would have to wait until a satellite is in view of its limited sight; in very sheltered locations, satellites have to pass directly above the 306 359 6956 Forman 1 Kalia Furman 8 Kallio 03.52:34 p.m. 05-17-2005 9127 transmitting device and satellite can communicate, thus severely restricting the minutes per day of satellite communication capability.
Not only may there be limited periods of time in which data can be transmitted from a device, there can also be significant costs associated with the bandwidth of messages transmitted over the system. In more populous regions with more options for wireless communication and more accessibility to these systems, bandwidth and the number of transmissions might not be a significant cost, both in resource utilization of the wireless communication system and actual billing cost. This may be different in remote locations where battery power is heavily utilized and power requirements of the transmitting device have to be minimized. In more remote locations it is often just not suitable to send location data position by position in separate transmissions either because the satellites are not in range frequently enough to make repeated transmissions over relatively small time intervals feasible. Even in areas with readily accessible wireless communication ~ s infrastructures, it might be simply desirable to reduce ttee bandwidth costs and number of transmissions of a transmission device.
SUMMARY OF ~ INVENTION
306 359 6956 Furrnan l Kalio Forman & Kallio 03:53:03 p m. 05-17-2005 10 !27 It is an object of the present invention to address disadvantages in the prior art.
A tracker device comprising: a GPS module; a GPS antenna; a transmitter module; a transmitter antenna; and a control module, is disclosed. The tracker device is a remote device to be carried with a person, a vehicle or other object to be tracked from a remote location. The tracker device can use the GPS module to dctcrrrtine its position and forward location data to a remote location so that either operators at a remote location can track the movements of the tracker device, or the information can be forwarded to another party using a remote device, informing a user of the remote device where the lo tracker device is located.
In one embodiment of the invention, the tracker device is operative to transmit data packets through a satellite communication system back to a central server located at a remote location. At the central server, the data packet is parsed and the location data contained in the data packet is processed to determine a history of previous locations of the tracker device. This location data is stored at the central server and provided to a remote device so that a subscriber can track the movements of a specific tracker device.
Rather than the tracker device transmitting a single set of location coordinates and other 2o associated position data at relatively short intervals to the central server, the tracker device assembles a data packet containing at least one time stamp and a number of 306 359 6956 Forman 1 Kalio Furman 8 Kallio 03:53:33 p.m. 05-17-2005 11 I27 - Page b -coordinates indicating the location of the tracker device over a period of time. Typically, the time stamp will coincide with the time the tracker device was at the first set of coordinates. Each additional set of coordinates assembled into the data packet will then be timed a predetermined interval of time after the preceding set of coordinates. When the data field is filled with the desired number of sets of coordinates the tracker device will finish assembling the data packet and transmit it to the central server.
The central server receiving the data packet will be able to parse it and getting the time stamp and knowing the approximate time intervals will be able to determine past t0 locations of the tracker device at approximate times. Because a number of coordinates separated by relatively small time intervals are transmitted together in the same data packet, the central server can use the different locations and their approximate times to determine a wide range of other values such as approximate direction of the tracker device, approximate velocity of the tracker device, and other information related to the is movement of the tracker device.
The central server can build a relatively complete history of the past locations of the tracker device with substantially fewer data packets having to be transmitted.
This is especially beneficial when the overhead costs for the wireless infrastructure are relatively 2o high or the resources available are limited, however, it could also be used to simply reduce the amount of transmissions required by the tracker device.
306 359 6956 Forman 1 Kalio Furman 8 Kallio 03v 54x05 p m. 05-17-2005 12 !27 DESCRIPTION OF THE DRAWI1~1GS:
While the invention is claimed in the concluding portions hereof, preferred embodiments are provided in the accompanying detailed description which may be best understood in conjunction with the accompanying diagrams where like parts in each of the several diagrams are labeled with like numbers, and where:
t0 Fig. 1 is a schematic diagram of a tracker device, in accordance with the present invention;
Fig. 2 is a schematic diagram of a personnel tracking and monitoring system incorporating the tracker device of Fig. 1, in accordance with the present invention;
Fig. 3 is a schematic diagram of a data packet containing location data, in accordance with the present invention; and 2o Fig. 4 is a method of assembling a data packet, in accordance with the present invention-30fi 359 6956 Furman 1 Kalio Furman & Kallio 03:54x28 p.m 05-17-2005 13/27 DETAILED DESCRIPTION OF THE ILLUSTRATED EMBODIMENTS
Fig. 1 schematically illustrates a tracker device 10 comprising: a GPS module 12; a GPS
antenna 13; a transmitter module 14; a transmitter antenna 15; a control module 16 and an input/output interface module 18. The tracker device 10 is a remote device that can be transported with a person or object. The tracker device 10 can determine its position and transmit this position data to a remote location, allowing the position of a tracker device to 10 to be determined at the remote location.
The GPS module 12 is a GPS receiver operative to receive global positioning satellite signals using the GPS antenna 13 and process these signals into position and other data.
t5 The transmitter module 14 is operative to transmit data packets from the tracker device 10. Although this transmitter 14 could be operative to transmit data over any wireless infrastructure system such as a terrestrial cellular telephone system or some other system, in one embodiment of the invention it is contemplated that the transmitter module 14 would be a satellite transmitter operative to transmit data via satellite such as the 20 OrbcommTT'' satellite system.
306 359 6956 Forman 1 Kalio Forman & Kallio 03-54'55 p.m. 05-17-2005 14 !27 The control module 16 controls the operation of the tracker device IO and is in communication with the GPS module 12, transmitting module 14 and I/O module 1$.
The control module 1b receives location data from the GPS module 12 and tin store this data. Additionally, the control module 16 is operative to assemble and format data packets at determined intervals and transmits these assembled data packets using the transmitting module 14 over the wireless infrastructure. In addition, the control module 16 controls the general operation of the tracker device 10 such as activating and deactivating the GPS module 12 and controlling the mode of operation of the tracker device 10 (i.e. receiver on, unit on low-power sleep, etc.).
l0 Optionally, the programming of the control module 16 can be altered remotely.
The transmitter/reeeiver module 14 can receive data that can alter the progamming of the control module 1b allowing the programming of the control module 16 to be altered remotely. Parameters such as the interval between times of transmission of data packets containing location data by the tracks device 10 can be altered remotely without requiring the tracker device 10 to be taken in for servicing or an on-site visit made for servicing. Also, the programming of the tracker device 10 can be altered remotely without requiring the operator of the tracker device 10 to have to make any changes to the tracker device 10 by him or herself.
306 359 6856 Forman 1 Katio Forman 8 Kallio 03:55:25 p.m. 05-17-2005 15127 The 1l0 interface module 18 can be attached to sensor inputs, outputs and/or other interfaces to be connected to the tracker device 10. Any inputs can be monitored by the control computer 16 and the control computer 16 can implement a pre-programmed action when certain conditions are met. The 1/0 interface module 18 can also allow the s attachment of a number of outputs that allows the control computer 1b to provide outputs when pre-determined conditions are met. For example, a temperature sensor could be connected to the 1/O interface module 18 to monitor the temperature of the contents of a container the tracker device 10 is attached to. If the temperature of the contents of the container drops below a specified level or cacceeds a specified level, the control computer 16 can transmit a message back to the central server 110 to alert people to the detected condition and provide an output through the 1l0 interface module I8 that will activate a backup environmental control.
The I/O interface module 18 can also be used to control an ezternal device remotely through a serial connection.
Fig. 2 is a schematic illustration of an overall system using the tracker devices 10 where the wireless infrastructure is a satellite communication system. The system comprises:
tracker devices 10; global p~itioning satellites 50; communication satellites 100; a 2o gateway station 105; a data network 107; a central server 110; and a remote terminal 1 Z0.
The tracker device 10 determines position data using the GPS satellites 50 and transmits 306 359 6956 Furman I Kalio Furman 8 Kallio 03:55:57 p m05-17-2005 16 !27 - Page l 1 -location data based on this position data to the central server 110, allowing a person using the remote tetrainal 120 to access this location data.
In operation, each of the tracker devices 10 will receive signals from the global positioning satellites 50 and from these signals determine position data. Each tracker device 10 log9 this position data and at intervals the tracker device 10 generates a data packet containing location data and transmits the data packet using the transmitter antenna 15 to the communication satellites 100.
a0 The communication satellites 100 are typically low-earth orbit satellites.
This allows data transmitted to the communication satellites 100 to be transmitted with lower powered transmitters, but because of the orbits of the communication satellites 100, the satellites 100 are not always in communication with the tracker devices 10.
This is especially true in remote locations. The tracker devices 10 transmit location data to the t5 communication satellites 100 using a store and forward method. If a communication satellite I00 is not in view, the tracker devices 10 store the data packets in memory anti! a communication satellite 100 comes into communication with the tracker device 10. Once the communication satellite I00 has come into communication with tracker device 10 the tracker device IO will forward or transmit the data packet to the communication satellite 20 100.
306 359 6956 Forman 1 Kalio Forman 8 Kallio 03:56x27 p.m 05-17-2005 17 l27 Once a data packet has been transfured to a communication satellite 100, the communication satellite 100 transmits the data packet to a gateway station 105. Again, the communication satellite 100, because of its orbit, is not always in communication with a gateway station 105. The data packet is typically transmitted to the gateway station 105 in a stare and forward method, whue the communication satellite 100 stores the data packet until the communication satellite 100 is in communication with a gateway station 105 and then transmits the data packet to the gateway station 105.
Generally, although not necessarily, the tracker device 10 can be operative to implement t0 an acknowledge-or-retransmit algorithm to ensure successful transmission of the data packets. When a data packet is received by the gateway station 105, the gateway station 105 can transmit an acknowledgement of receipt back through the communication satellites 100 to the tracker device 10 which is operative to receive incoming data packets. The tracker device 10 will wait after transmitting a data package for this acamowledgment of receipt by the gateway station 105. If no acknowledgment of receipt is received by the tracker device 10, the tracker device 10 will attempt to retransmit the data packet and can, continue to do so until an acknowledgment of receipt by the gateway station 105 is received by the tracker device 10.
2o From the gateway station 105, the data packet is transmitted over a data network 107 to a central saver 110. The central server 110 logs the data packets and identifies them in 306 359 6956 Furman 1 Kalio Furman 8 Kallio 03:56:59 p.m. 05-17-2005 18127 respect of which tracker device 10 transmitted the data packet. The central server 110 can then store the different locations of each tracker device 10 at different times and build a history of locations the tracker device 10 has been located over time.
Although Fig. 2 illustrates the system using a low earth orbit satellite system as the wireless infrastructure being used to transmit data packets from the tracker devices 10 to the central server 110, it is contemplated that other suitable wireless communication systems capable of transmitting data from the tracker devices 10 to the ventral server 110 could be used. For example, the tracker devices 10 and central server 110 could be communicating through a cell phone wireless network or other such system.
The remote device 120 can be a cell phone, pager, fax or other device where an operator of the remote device 120 can be quickly notified of the position of the tracker device 10.
Alternatively, the remote device 120 could be a personal computer, PDA or other device ~5 in communication with the central server 110 over a TCP/IP connection or wireless network and the location information could be forwarded to the remote device 120 in an email or through a specific program running on the remote device 120. The central server 110 can communicate a last position of the tracker device 10 to the remote device 120 or a number of past locations. 1n one embodiment, the remote device 120 has a map 2o client that can display the locations of a tracker device 10 overlaid on a map displayed on the remote device 120.
306 359 6956 Forman 1 Kalio Ftxman & Kaliio 03:57'30 p.m. 05-17-2005 19127 Pad t4 -While the use of a remote device 120 is discussed herein, it will also he understood that the general method of communication comprising assembling a number of interval location data into a single packet and communication thereof for parsing and logging in a central server is also contemplated to be a broad embodiment of the method which is understood to be within the scope of the presant disclosure.
Fig. 3 is a schematic illustration of a data packet 200 in accordance with the present invention. The data packet 200 comprises: a packet header 205; a data field 20'1 and a to packet trailer 209.
The packet header 205 is used to transmit the data packet 200 through the system as is well known in the art. The packet header 205 typically contains a source address, a destination address, and other information such as the length of the data packet 200, that ~5 enable the transmission of the data packet 200 to the central server 110. A
person skilled in the art will appreciate the packet header 205 can vary depending upon the type of transmission protocols used and the wireless infrastruetux~e, etc.
Additionally, additional headers will likely be added to the data packet 200 as it is transmitted through the system to the central server 110.
2~
306 359 6956 Furman 1 Katio Fucman 8 Kallio 03:57x58 p.m. 05-17-2005 20 !27 The packet trailer 209 is also typically present as required by the protocol used to transmit the data packet 200 and typically contains further information to help with the transmission of the data packet 200 such as a checksum, although it may not be required in every implementation of the invention.
The data field 20? contains the data the tracker device 10 transmits to the central server 110 and in one embodiment comprises: a time stamp 210; a first set of coordinates 220;
and a plurality of additional sets of coordinates 222, 223, 224 and 225.
Although five coordinates are illustrated in Fig. 3, a person skilled in the art will appreciate that this t0 number is only illustrative. Various numbers of coordinates could be included in the data field 207 depending on the desired length of the final data packet 200.
Time stamp 210 will indicate a time that the tracker device 10 was at the first set of coordinates 220. The neat additional set of coordinates 222 indicates the location of the tracker device 10 after a known interval of time. Each additional set of coordinates 223, 224 and 22S indicate the location of the tracker device 10 after a known interval of time following the preceding set of coordinates. In this fashion, a number of different locations of the tracker device 10 are included in a single data packet 200.
The approximate time the tracker device 10 was at each set of additional coordinates 222, 223, 224 and 225 is determinable because the time stamp 210 will indicate when the tracker device 10 was ai the first set of ooondinates 220 and then using the known 306 359 6956 Forman 1 Kalio Forman 8 Kallio 03:58-30 p.m. 05-17-2005 21 !27 - Page l 6 -intervals of time between the additional sets of coordinates 222, 223, 224 and 225, the time the tracker device 10 was at each additional set of coordinates 222, 223, 224 and 225 can be approximated.
Fig. 4 illustrates an alternative embodiment of the data packet 300 containing more than one time stamp. Data packet 300 contains: a packet header 305; a data field 307; and a packet trailer 309. Data field 307 contains a first time stamp 310; a first set of coordinates 320; a s~ond time stamp 330; a second set of coordilnates 322; and a number of additional sets of coordinates 223, 224 and 225. Data packet 300 contains more than Io one time stamp so that a second time stamp can be associated with a set of coordinates, either to provide a time reference when there is no position data available after a predetermined time interval, to include a set of coordinates outside the predetermined time intervals or to serve as a recalibration time stamp to more accurately determine the times of the tracker device 10 was at the coordinates. Addition, every set of coordinates Is could have a time stamp associated with it.
Referring again to Fig. 1, when the GPS module 12 receives signals from the global positions satellites from the GPS antennae 13, it convents these signals into position data, coordinates indicating the position of the tracker unit 10. The tracker device 10 then 2o assembles various position data in to location data in a data packet. Fig.
5 illustrates a flow chart of the assembly of a data packet by the tracker device. When a new data 306 359 6956 Furman 1 Kalio Furman 8 Kallio 03-59:01 p.m. 05-17-2005 22127 packet is to be assembled, the tracker device starts the process 400. The tracker device determines a time stamp and a first set of coordinates corresponding to the time stamp and assembles these values into the proper data packet fields 410. The tracker device will check to see if a predetermined interval of time has passed 420 and once it has, the s tracker device will determine an additional set of coordinates for the neat location of the tracker device and assemble these values into the proper data packet fields 430. After entering this additional set of coordinates, the tracker device will check to see if the data fields are full 440. If the data fields are not full, the tracker device 10 will then wait another specified interval of time 420 and then determine the next additional set of t0 coordinates and add this set of coordinates to the proper data packet fields 430. The tracker device will continue adding the additional coordinates at predetermined intervals until the data fields are full 440 and once the data packet is full, the tracker device will transmit the data packet 450 and the method will end 460.
15 Referring again to Fig. 2, once the data packet is assembled and transmitted to a communication satellite 100, the communication satellite 100 will transmit the data packet 200 to the central server 110. The data packet 200 is transferred from the tracker device 10 to the communications satellite 100, through the gateway 105 and over the network 107 to the central server 110.
306 359 6956 Furman 1 Kalio Furman 8 Kaliio 03x59 32 p.m. 05-17-2005 23!27 - Page I 8 Once the data packet 200 has been transmitted to the central server 110, the central server 110 can strip out the data field 207 and log the coordinates 220, 222, 223, 224, and 225 contained within the data field 207. The central server 110 knows when the tracker device 10 was at the first set of coordinates 220 by the time indicated by the time stamp 210. Then by using the predetermined time intervals between the additional sets of coordinates 222, 223, 224, the central server 110 can start from the time stamp 110 and using the first set of coordinates 222, build a chart of a number of different locations of the tracker device 10 over a period of time. From the data packet 200, the central server 100 is able to determine a number of locations of the tracker device 10 over a period of t0 time allowing a database of past locations of a device tracker 10 to be built with fewer transmitted data packets from the device tracker 10. Because the central server 110 can determine locations and times from the data packet 200, the central server 100 can approximate speeds and directions of the tracker device 10 from these coordinates without requiring the transmission of speed and direction data from the tracker device 10.
The foregoing is considered as illustrative only of the principles of the invention.
Further, since numerous changes and modifications will readily occur to those skilled in the art, it is not desired to limit the invention to the enact construction and operation shown and described, and accordingly, all such suitable changes or modifications in strucriue or operation which may be resorted to are intended to fall within the scope of the claimed invention.
306 359 6956 Furman 1 Katio Fucman 8 Kallio 03:57x58 p.m. 05-17-2005 20 !27 The packet trailer 209 is also typically present as required by the protocol used to transmit the data packet 200 and typically contains further information to help with the transmission of the data packet 200 such as a checksum, although it may not be required in every implementation of the invention.
The data field 20? contains the data the tracker device 10 transmits to the central server 110 and in one embodiment comprises: a time stamp 210; a first set of coordinates 220;
and a plurality of additional sets of coordinates 222, 223, 224 and 225.
Although five coordinates are illustrated in Fig. 3, a person skilled in the art will appreciate that this t0 number is only illustrative. Various numbers of coordinates could be included in the data field 207 depending on the desired length of the final data packet 200.
Time stamp 210 will indicate a time that the tracker device 10 was at the first set of coordinates 220. The neat additional set of coordinates 222 indicates the location of the tracker device 10 after a known interval of time. Each additional set of coordinates 223, 224 and 22S indicate the location of the tracker device 10 after a known interval of time following the preceding set of coordinates. In this fashion, a number of different locations of the tracker device 10 are included in a single data packet 200.
The approximate time the tracker device 10 was at each set of additional coordinates 222, 223, 224 and 225 is determinable because the time stamp 210 will indicate when the tracker device 10 was ai the first set of ooondinates 220 and then using the known 306 359 6956 Forman 1 Kalio Forman 8 Kallio 03:58-30 p.m. 05-17-2005 21 !27 - Page l 6 -intervals of time between the additional sets of coordinates 222, 223, 224 and 225, the time the tracker device 10 was at each additional set of coordinates 222, 223, 224 and 225 can be approximated.
Fig. 4 illustrates an alternative embodiment of the data packet 300 containing more than one time stamp. Data packet 300 contains: a packet header 305; a data field 307; and a packet trailer 309. Data field 307 contains a first time stamp 310; a first set of coordinates 320; a s~ond time stamp 330; a second set of coordilnates 322; and a number of additional sets of coordinates 223, 224 and 225. Data packet 300 contains more than Io one time stamp so that a second time stamp can be associated with a set of coordinates, either to provide a time reference when there is no position data available after a predetermined time interval, to include a set of coordinates outside the predetermined time intervals or to serve as a recalibration time stamp to more accurately determine the times of the tracker device 10 was at the coordinates. Addition, every set of coordinates Is could have a time stamp associated with it.
Referring again to Fig. 1, when the GPS module 12 receives signals from the global positions satellites from the GPS antennae 13, it convents these signals into position data, coordinates indicating the position of the tracker unit 10. The tracker device 10 then 2o assembles various position data in to location data in a data packet. Fig.
5 illustrates a flow chart of the assembly of a data packet by the tracker device. When a new data 306 359 6956 Furman 1 Kalio Furman 8 Kallio 03-59:01 p.m. 05-17-2005 22127 packet is to be assembled, the tracker device starts the process 400. The tracker device determines a time stamp and a first set of coordinates corresponding to the time stamp and assembles these values into the proper data packet fields 410. The tracker device will check to see if a predetermined interval of time has passed 420 and once it has, the s tracker device will determine an additional set of coordinates for the neat location of the tracker device and assemble these values into the proper data packet fields 430. After entering this additional set of coordinates, the tracker device will check to see if the data fields are full 440. If the data fields are not full, the tracker device 10 will then wait another specified interval of time 420 and then determine the next additional set of t0 coordinates and add this set of coordinates to the proper data packet fields 430. The tracker device will continue adding the additional coordinates at predetermined intervals until the data fields are full 440 and once the data packet is full, the tracker device will transmit the data packet 450 and the method will end 460.
15 Referring again to Fig. 2, once the data packet is assembled and transmitted to a communication satellite 100, the communication satellite 100 will transmit the data packet 200 to the central server 110. The data packet 200 is transferred from the tracker device 10 to the communications satellite 100, through the gateway 105 and over the network 107 to the central server 110.
306 359 6956 Furman 1 Kalio Furman 8 Kaliio 03x59 32 p.m. 05-17-2005 23!27 - Page I 8 Once the data packet 200 has been transmitted to the central server 110, the central server 110 can strip out the data field 207 and log the coordinates 220, 222, 223, 224, and 225 contained within the data field 207. The central server 110 knows when the tracker device 10 was at the first set of coordinates 220 by the time indicated by the time stamp 210. Then by using the predetermined time intervals between the additional sets of coordinates 222, 223, 224, the central server 110 can start from the time stamp 110 and using the first set of coordinates 222, build a chart of a number of different locations of the tracker device 10 over a period of time. From the data packet 200, the central server 100 is able to determine a number of locations of the tracker device 10 over a period of t0 time allowing a database of past locations of a device tracker 10 to be built with fewer transmitted data packets from the device tracker 10. Because the central server 110 can determine locations and times from the data packet 200, the central server 100 can approximate speeds and directions of the tracker device 10 from these coordinates without requiring the transmission of speed and direction data from the tracker device 10.
The foregoing is considered as illustrative only of the principles of the invention.
Further, since numerous changes and modifications will readily occur to those skilled in the art, it is not desired to limit the invention to the enact construction and operation shown and described, and accordingly, all such suitable changes or modifications in strucriue or operation which may be resorted to are intended to fall within the scope of the claimed invention.
Claims
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA 2507585 CA2507585A1 (en) | 2005-05-17 | 2005-05-17 | Reduced bandwidth communications in remote location tracking applications |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA 2507585 CA2507585A1 (en) | 2005-05-17 | 2005-05-17 | Reduced bandwidth communications in remote location tracking applications |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA2507585A1 true CA2507585A1 (en) | 2006-11-17 |
Family
ID=37450468
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA 2507585 Abandoned CA2507585A1 (en) | 2005-05-17 | 2005-05-17 | Reduced bandwidth communications in remote location tracking applications |
Country Status (1)
| Country | Link |
|---|---|
| CA (1) | CA2507585A1 (en) |
-
2005
- 2005-05-17 CA CA 2507585 patent/CA2507585A1/en not_active Abandoned
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP5362539B2 (en) | Satellite positioning reference system and method | |
| US6510381B2 (en) | Vehicle mounted device and a method for transmitting vehicle position data to a network-based server | |
| US6188719B1 (en) | Radiocommunication system repeater | |
| AU749670B2 (en) | Method and apparatus for operating a satellite positioning system receiver | |
| US6088571A (en) | Method and apparatus for multi-constellation satellite broadcast with error correction | |
| EP1555542A2 (en) | Method and system for transmitting assistance location data for fleet and asset management | |
| EP1555543A2 (en) | Method and system for tracking mobile telemetry devices | |
| US7672639B2 (en) | Method and system for routing telemetry in a simplex mode | |
| CA2221957A1 (en) | Asset location system | |
| US20060244587A1 (en) | Method and apparatus for providing transmission of compressed telemetry data in a tracking system | |
| US8799324B2 (en) | Method and system for mobile telemetry device prioritized messaging | |
| US20050156735A1 (en) | Method and system for remotely configuring mobile telemetry devices | |
| US8120528B2 (en) | Apparatus for satellite telecommunications | |
| US20050157856A1 (en) | Method and apparatus for providing an externalized interface to mobile telemetry devices | |
| US20050055407A1 (en) | Low earth orbit communication system | |
| US20050174283A1 (en) | Location information notifying system and communication terminal | |
| US20090119002A1 (en) | Terminal For Satellite Navigation System | |
| CA2507585A1 (en) | Reduced bandwidth communications in remote location tracking applications | |
| KR100783724B1 (en) | System and method for synchronizing time using gps | |
| CA2507718A1 (en) | Satellite-enabled remote location monitoring device with two-way distress signal capability | |
| RU65703U1 (en) | LOW-ORBIT SYSTEM OF PACKAGE DATA TRANSMISSION AND DISPATCHER TELEPHONY | |
| RU82971U1 (en) | RADIO COMMUNICATION SYSTEM WITH MOBILE OBJECTS | |
| Soni | An Integrated Satellite Based Asset Management System. | |
| US20030008665A1 (en) | Method and apparatus for providing travel instructions and related tracking information to a GPS capable wireless device | |
| EP1393468B1 (en) | Method, apparatus and computer program product for implementing and organizing an ad-hoc aviation data communication network |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| FZDE | Dead |