Technical field

The invention relates to a system and a method for monitoring of an object, more specifically a system which triggers an alarm and tracing in ease of indication of 5 theft.

Background

There are man monitoring systems where an identity label is attached to an object, and where the position of the object is determined by means of wireless

K> communication with the identity label. The motion of the object may be estimated by deteccting the position of the object at different points of time.

Acti ve and passi ve RFID are examples of a technique which is used with identity labels.

Passive RFID means, that an RFlD-chtp receives a radio- frequency (RF) 5 reading signal and uses the energy in the reading signal to return its ID and possibly other data. This technique may for example be used for tracing of luggage on an airport by -integrating an RFJD-chip into a tag which is attached to luggage. Readers positioned along a conveyor belt can read the RFiD-chips, and use the information to route the luggage to the right aircraft. A type commercially available passive RFID- units has o about 0,5 mm diameter and has antennas of a few cm. Both chip and antennas may have a thickness of a few tenth of a ram, Such RFID-units can be delivered on Him which can be sticked on a surface. Passive RFiD are also used among others to identity labeling of animals by implanting a chip the size of a rice grain belo the sk in of the animal. The unique identity of the RFID chip may later be read out, for instance at a s veterinarian, and being associated with the owner and other data in a database. Passive RFiD-chips may thus be relatively small-sized, and therefore are relatively easy to hide in or on an object. However,, the range is a substantial constraint for use of passive RFID. The range for passive RFiD depends on the power of the reading signal, and is usual ly in the magnitude of a few meters or less.

With acti ve RFID, the RFID-chip has a power supply of its own. The range is thus not limited by the power of an incoming signal. Instead active RFID may need more energy than passive RF.ID, which means larger and heavier batteries or power supply via a cable,

GPRS (General Packet Radio System) and GPS (Global Positioning System) are examples of sy stems that can be used to determine the position of an object .

GPRS bearing is a service which is offered by major mobile network owners, and is performed in that a mobile unit is connected to up to three base stations in the mobile network. The base stations determine the signal strength of the mobile unit. As the network owner knows the exact position of the base stations, it is possible to determine the position of the mobile unit by triangulation. GPRS-positioning assumes thai the mobile unit is switched on and connected to at least one base station. The positioning precision depends on the spacing between the base stations, and varies in today's GSM-network in Norway from about hundred meters in densely populated areas to a few kilometers in rural areas. Corresponding systems based on triangulation of mobile unit may be implemented in different mobile networks, and it is expected that other systems will be preferred if, when or where the density of base stations is greater than in today's GSM-network in Norway, it should also be appreciated that "iriangulation" hereinafter is not limited to GPRS, but also comprises well-known bearing methods with hand-hold directive antennas which are independent of mobile networks,

GPS is a positioning system in which satellites with, known orbital tracks broadcast radio signals with information about their track and precise information about when the signal was transmitted. A GPS receiver on the earth surface which receives signals from multiple satellites can use this information to determine its own position. The GPS receiver can calculate its position with precision of about 7m without corrective signals. The precision may be improved to about 2m with corrective signals, and to some cm with special equipment. Iridium is a second satellite based positioning system with similar properties. Hereinafter "satellite based positioning system" is used for GPS, iridium and other satellite based positioning systems.

Common for these systems is that they have a precision of about iOm or less, and that the broadcasted radio signals of the satell ites must be able to reach a receiver.

Battery-powered tracing units which are hidden on or in an asset may for instance be used to locate an automobile-, a boat, luggage or other asset after theft. Battery-po ered tracing units may also be used to find a pet that has escaped or in a "fetter" with a tracing unit being used to check if a convicted person is located within a defined area.

Chipset and modules for the techniques described so far are commercially available, and prices and dimensions are constantly reduced. It is therefore desired to use existing technique as much as possible, A skilled man. in the art might select a technique which fits to the relevant application.

A general problem with battery-powered units is as mentioned that the amount of energy which can be stored in a battery is .limited. It is therefore common to let the electronics- go into hibernation when it is not in active use. US 2004/034470 Al describes a tracing unit that has such a hibernation state in order to save energy, and which is activated by motion. Motion activation may be suitable for theft alarm, but does not fit. to trigger wake-up of a tracing unit on an animal which constantly is in motion. Motion activation of a theft protection on, for instance, an automobile, bicycle or boat requires in addition that the user must remember swi tching off the theft protection prior to he/she moves the automobile, the bicycle or the boat. There is thus a need for a unit which is not activated by motion.

Norwegian patent NO 326999 B 1 describes a system for monitoring animals where a collar is laid around the neck of an animal. The collar comprises a GPS unit for position finding, and means for two-way communication with a peripheral communication unit. The system further comprises a communication unit for activation of and reception of signals from a passive probe implanted into the body of the animal. The probe detects one or more physiological parameters, in the animal and communicates these parameters to the communication unit. Alarm is given if a physiological parameter differs from predetermined values. The alarm may be an acoustic signal which is given by means of a speaker integrated into the collar. This signal is intended to temporarily scare predators, and it is disclosed to be essential that a human arrives at the location shortly after the alarm has Occurred. For this objective the alarm can, also being sent as a radio signal to the peripheral communication unit.

A purpose of the present invention is to provide an improved system which solves one or more of the problems associated with the prior art. Summary of the invention

This is solved according to the present invention, by a system for monitoring of an object, comprising a communication unit which in a normalcy is placed close to the object, which communication unit contains a. reader, a radio station adapted to communication with a base station and an electrical energy supply. The system is characier- rized by an ID unit in or on the object, which I ^' D unit has a unique ID and contains a recei ver and transmitter adapted to transmit the unique ID of the chip as a response to an incoming signal from the reader, and an alarm circuit placed between the reader and the radio station, wherein the alarm circuit is configured to trigger an alarm if the reader does not receive a response from the ID unit.

An ID unit may be relatively small, and hereby easy to hide in or on an object. For example a passive RFTD-unit of a type mentioned in the introduction may be used in the invention. By the ID unit being hidden in or at the object, it can in some appiica- lions be used to identify the object and/or prove ownership, f inst after theft or theft slaughter. A communication unit positioned close to the object can contain larger and/or other components than a communication unit in or on the object. In a first embodiment the communication unit may require as low as possible power, is operated with energy from a small battery and is attached in a collar of a farm animal or pet. The battery may be charged by a generator which converts motion energy into electrical, energv. A broken link between the communication unit and the ID unit mav inst indicate that the animal has ceased to move or thai the collar is removed from the animal. In a second embodiment the ID unit may be hidden in a suitcase or other asset, and a battery-operated communication unit is placed hi the same asset. A broken link between the communication unit and the ID unit may f inst indicate that the communication unit is removed by thief who removes visible theft protection devices or tracing units. In a third embodiment the communication unit may be mounted in a vehicle, a vessel and Is operated with energy from a larger battery; f Inst a L2V car battery. Alternatively the communication unit may be mounted fixed, finst in a garage or on a mooring space, and is operated with energy supplied from local mains via fixed wiring. In this embodiment the alarm may be triggered when the vehicle or the vessel with the ID unit is removed from the communication unit such that the eonnee- tion between them is lost. This can indicate theft of f inst a car, a bicycle, a vessel or similar.

in these and other embodiments an alarm may be triggered when the link, between the communication unit and the ID unit is lost. The alarm may be sent over a mobile network and trigger a reaction shortly after it is triggered, in a preferred embodiment the communication unit is connected to means for position finding, whereby it is possible to trace the communication unit after theft. Said means for position finding may also be used to locate an animal, an asset or a different object as needed. Other features and advantages of the present invention are disclosed by the patent claims below.

Brief description of the figures

Hie invention will be described in more detail in the following detailed description with reference to the attached drawings, in which:

Figure 1 shows a system according to the invention.

figure 2 shows an embodiment .with means for position finding.

Figure 3 shows a. generator which may be used in embodiments of the invention.

Detailed description

The drawings are schematic principle drawings which are intended to illustrate the in vention. They are thus not to scale, and a number of details are omi tted for better clarity.

Figure 1 shows a system lor monitoring an object 200. comprising communication unit I GO placed close to the object. That can be in a collar strapped to an animal. In another application the communication unit 1 0 may be mounted in a garage or at a mooring space a a part of a supervisory system for a car, a bicycle, a boat and so forth

The. communication unit contains a reader 1 10, which in a preferred embodiment is capab le of reading a passive RFID-chip, fo instance of a type which is described in the introduction. A radio station 120 is adapted for communication with a base station 130. The radio station 120 ma for instance be a commercially available chipset which is operable to communicate with base station 130 in the GSM network. Any existing and future network 150 for communication ^' with mobile units can be used in the present invention. The network 150 is merely a means of transmitting an alarm to the owner or a central, such that it is possible to respond quickly when something happens. In figure 1 the owner or central is represented by a terminal 160, which is operable to receive an alarm, f inst a SMS-message, and transmit an instruction. This is described in more detail below.

An electrical energy supply 140. f inst a battery pack or an outlet irom the mains, supplies energ to the components in the communication unit. An energy supply 140 in the form of a battery pack may optionally be charged by a generator 300 (figure 3). The generator 300 may for instance convert motion energy into chemical energy in the battery pack, and being pari of a system for monitoring animals. In such an application the battery will be charged when the animal is moving, and will not. be charged when the animal is resting or is not moving for other reasons. Electrical energy will hereby be available from the energ supply .140, here the battery pack, when the animal with the generator 300 is not moving, while a generator 300 without battery would not be able to alert; if the animal ceases to move. The generator is described in more detail in connection with figure 3 below.

The system further comprises an identity unit, hereinafter ID unit. 125 in or at the object, which ID unit 125 has a unique identity label, f inst a serial number or similar. The unique identity label is hereinafter called "unique ID" for convenience. Additionally, the ID unit 12$ contains in addition to the unique ID also a receiver and a transmitter adapted to transmit the unique ID of the chip as a response to an incoming signal from the reader 1 10. As mentioned in the introduction, a passive RFlD-ehip may ^¬ be relatively small It can thus be hidden relatively eas in or on an object. In a first application a passive RFI.D-unit may be placed under the skin of an animal. In different applications the RFID-chip may be hidden under the lining in a suitcase or in other lussaec- on a vehicle, vessel or similar.

The object of passive RF!D is to avoid a bulky energy supply. In passive R.FID the energy in a radio-frequency signal is used. The man skilled in the art knows that the energy in an electromagnetic signal increases proportionally with the frequency, and that it is possible to use various frequency bands where the most long-wave read-out signals yield shortest range. The frequency may be increased to f inst microwave level, which transfers more energy, which thus can be used for increased range if desired. The man skilled in the art knows thai inductive coupling between two coils can transfer energy, without the frequencies necessarily being in the RF range. Passive ID unit consequently means, that each unit which can receive energy wirelessly and use the received energy to return its unique ID, independent of the signal being radio frequency or not. When the ID unit 125 is hidden in or on the object, it can be used to identify the object and/or prove ownership, f insi after theft or theft slaughter, it can also be used to identif a pet that has escaped and been found, such thai the owner can be in formed.

In the first embodiment described above, no contac between ID unit 125 and the reader 1 10 may indicate that the animal has lost the collar or that someone has removed the collar, in the application where a small ID unit is hidden in the luggage or similar, no contact indicates that someone has removed the visible theft protection, that is the communication unit 100. in the third application the contact is lost between the ID unit 125 and the reader 110 when the vehicle or the vessel is removed from the fixed mounted communication unit 100. In all these eases lost contact between the reade 110 and ID-label 125 may indicate theft. An alarm circuit 1 5 is placed betw een the reader 1 1 and the radio station 120. The alarm circuit 1 15 triggers an alarm when the reader 1 10 does not achieve contact with the ID unit 125. That can be an audible or visible alarm, and/or a message which is sent t a predetermined receiver, represented by terminal 160. over the communication network 1.50. When the alarm is triggered, it is advantageous to respond quickly, such that the animal can get a new collar before it has moved too far or such that the chances to solve a theft or theft slaughter are increased. In preferred embodiments the alarm unit 1 15 therefore transmits a message through the communication network 150, f insi a SMS-message in a GSM-network. One possible consequence is that searches and/or tracing are started.

Some embodiments of the system have therefore means for posit ion finding. This is described in more detail in connection with figure 2 below. Embodiments where the system lacks own means for position finding, and thus tracing, is particular suitable in applications where a vehicle or vessel is equipped with tracing means in advance, f inst a GPS unit that can be used to trace the object when the alarm is triggered. GPS- units with tracing functions are commercially available, and become constantly more common ϊη ears and boats. Generally, a terminal 160 may receive alarms or messages from the alarm circuit 1 15 through a communication network I ^' 50, and transmit instructions over the same network as illustrated by pointers between the radio station 120. the base station 1.30 the communication network 150 and the terminal 160 in figure I . The terminal 5 may for instance transmit instructions to the communication unit 100 to set the radio transmitter 120 in triangulation mode, as described in more detail below; Other transmitted instructions may go to a GPS unit outside the system which is described here. £ inst an instruction to said pre-mounted GPS-unit in a car or boat to launch tracing. The alarm circuit 1 15 transmits as mentioned preferably an alarm through the io communication network. In favorable embodiments the alarm circuit 1 15 has also

control functions which can accept instructions, f inst via SMS-message, from an authorized user. The instruction may for instance get the alarm circuit 1 15 to launch an audio signal such that it is most easily possible to locate the communication unit in the terrain _. , and/or enable tracing. Tracing may f inst be enabled by the communication unit i5 120 being set into triangulation mode, which is described in more detail below, and/or in that a relatively energy demanding position finding unit is activated and starts to determine its position based on satellite signals. In another example an instruction from an authorized user may stop the alarm when the user has forgotte that the theft alarm is switched on. and has driven or cycled away from the communication unit 100. Obvi-

^• 20 ouslyv it is important that the authorized user is duly authenticated, such that no third party can switch of alarms or transmit other instruct ions to the alarm unit. The man skilled in the art knows that secure authentication requires something the user owns, f inst a cell phone with a unique identity in a network and/or a certificaie, and something the user has knowledge about, f inst a PiN-code or a password. Methods and equipment

25 for authentication are outside the scope of this invention, and the choice of suitable equipment is thus left to the man skilled in the art.

In embodiments where the communication unit 100 is ^' fixed mounted, one knows where the communication unit is located, and it is- unnecessarily expensive to equi it with a position finding unit of its own. As described above, a position finding

.?o unit might already be installed in a vehicle or vessel.

Figure 2 illustrates an embodiment suitable for deployments wherein the communication unit 100 is movable, f inst on an animal or in a suitcase. In figure 2 the communication unit 100 is equipped with means for position finding 170, which is used to determine the geographical position of the radio station J 20, and thus the communication unit 100. Said means for position finding 170 may be in a first embodiment a radio transmitter which is used fo triangulation. for exampl e by use of GPRS or handhold direction-sensitive aerials as described above. The radio transmitter 1.20 can be used for triangulation, and may for this objective have an (optional) triangulation mode. The idea here is that the communication unit 100 has an operating mode with relatively low energy consumption, where the energy consumption among others is limited by a power-saving function which de-activates the transmitter 120 most of the time, and where the radio station 120 is revived and connects to the network for example once an hour or more rarely. In triangulatioii mode the power-saving function is deactivated such that the transmitter 120 transmits more often, such that it is possible to triangulate. Depending on the desired positioning precision GPRS or similar may be replaced by, or be supplemented by a position finding unit which itself determines its position by means of a satellite based positioning system. Said means for position finding 170 can in other words comprise for example receivers for GPS or iridium in addition to or instead of a radio transmitter for triangulation. The desire for precise position must be weighted against the need to save energy in the cases where the energy supply 140 is a battery pack on an animal and not an outlet from the mains or a large car battery. It is left to the man skilled in the art selecting an energy supply 140 and a possible position finding unit 170 which fits the relevant application.

Figure 3 is a principle drawing of a generator 300 which converts motion energy into electrical energy, and a communications unit 100 with a battery pack which corresponds to the electrical energy supply 140 in the appended patent claims. The generator 300 has a permanent magnet 3 10 which capable of being moved in a coil 320, for example forth and back as illustrated by double arrow. The letters N and S are merely intended to indicate that the element 320 is a permanent magnet with a north pole and a south pole S. The polarity and the design otherwise ha HO special significance. When the magnet 3 10 is moved inside the coil 320, a current is induced, and the electrical energy is transferred to the battery pack which represent the electrical the energy supply 140 in the patent claims. The permanent magnet 320 is in figure 3 suspended with a spring 330, The kinetic energy which can be transferred from the generator 300 to the battery 140 is proportional with the mass of the magnet and field strength. Permanent magnets based on one of the so-called rare-earth materials, that are element of the lanthanite-group ^' or scandium or yttrium, are suitable due to relatively high Held strength. Nowadays, for instance, a typical neodymium-magnet may have a field strength of 1,- 1 ,4T and relatively low price. The energy consumption of the communication unit 100 during 24 hours determines how much energy that must be transferred from the generator 300 during 24 hours. The energy consumption depends among others from how often it is desirable or necessary to communicate with the communication network 1 50 (figure 1), from mean distance to the base stations, that must be expected to increase in rural areas, and of corresponding frequency and -power which is needed to update the status for the ID-chip 125. When the energy consumption throughout 24 hours is known, the mean power of the generator can be calculated, in non-moving applications it is possible to supply power of f inst. 5V x 80mA ^~ 4( ⁾ 0mW from the ordinary mains. In. applications where the generator 300 is mounted in a collar of an animal, supplied power may be estimated by dividing with the time one may expect that the animal is active. Different species have different motion patterns and resting periods. In addition a large animal can carr a larger generator than a cat or dog. The size has significance among others for the mass of the permanent magnet 310 and diameter of the coil 320. Such a greater mass and larger diameter is expected to compensate for, that big animals generally are expected to move slower than small animals.

It is possible to connect more sensors, for example a temperature measurement unit, a motion measurement unit; an accelerometer and/or a pulse measuring unit which can give furthe information about the condition of an animal or a different object. The sensors can be monitored and controlled, f inst through the alarm unit 1 15, the radio station 120 and the communication network 150 as described in connection with figure 1 above. The main limitation for the number of sensors is nowadays the battery capacity, but it is expected that this may change as a consequence of progress in miniaiureza- tion and battery technology.

The present invention is defined in the patent claims below.