ES2264331A1 - Proximity detection system using coded and encrypted electromagnetic signals, has control unit that activates local and remote alarms once occurrence of proximity event is detected between transmitting and receiving systems - Google Patents

Abstract

The system detects proximity based on the interchange of coded and encrypted signals between two transmitting and receiving systems when each of the transmitting and receiving system is within the communication range of the other. The interchange of signals allows specific recognition between the transmitting and receiving systems. Once the occurrence of a proximity event is identified between the transmitting and receiving systems, a control unit activates different types of local and remote alarms by telephony.

Description

Proximity detection system.

Object of the invention

The present invention, as expressed in the set forth in this specification, refers to a system of detection of the proximity between two elements of a couple. The detection includes recognition of the encrypted identity of both elements and allows to manage an alarm system.

The system is based on the exchange between two electromagnetic signal emitter / receiver systems encoded and encrypted.

The invention falls within the technical field of Electrical communication techniques (H04), Secret Communication (H04 K), Coding - Decoding (H03M).

State of the art

There are proximity detection systems of people and objects that work by geographical location. Some of these systems are based on GPS (General Positioning System) or mobile telephony. In these systems no there is a direct peer detection but it is located individually each of the members of the pair from a remote control panel and subsequently it can be determined, with greater or Less precision, the distance between them. Besides, his operation is limited to areas with coverage in the case the mobile or open sky telephony, for systems based on the GPS

There are also detection systems for proximity based on direct communication between pairs of elements by radio signals. However most of These systems are designed to ensure that these elements are not separate, that is, activate alarms if the distance between them exceeds a threshold value (unlike the present invention thought to work normally with the two remote elements beyond a certain distance). Normal mode of operation of these systems, corresponds to the fact that the signal issued by one of the elements is received continuously by the other if it is close enough to the first. In these systems does not incorporate performance monitoring and the integrity of the elements that compose them.

The detection systems used for the monitoring and study of animal species, incorporate an emitter that is placed to the animal and that periodically transmits a signal which is received by a reception station, usually from considerable size, which allows to know the position of the animal (distance and direction).

In US Patents 6154665 and US 5943628 describes another proximity detector adapted to prevent theft of mobile phones in which an element associated with the owner from the mobile periodically emits an encoded signal that is received by mobile phone, estimating the distance between them and using that estimate to disable / lock the phone mobile if the distance between the two mentioned elements exceeds a preset threshold.

There are also devices for cars that trigger an alarm or action when the owner approaches to it (US Patent 5396070). In these systems, the owner It carries with it a module that emits a signal periodically and that is received and recognized by the system that incorporates the car if Find near it.

In some child protection systems incorporates an element in the form of a bracelet that places the child to protect and that incorporates an audible alarm that can be activated either at will with another module that emits a signal (US Pat. 5936530) or automatically when overcoming a certain distance (US Patent 6542080), with the possibility of controlling in a manner Remote volume.

In all the systems described above there is only one transmitter and one receiver, with no return of the signal between they.

In US Patent 5646593 another one is described proximity detector for children based on an emitting device that the father carries and that sends an encoded signal (which identifies to the father) periodically and that upon being received by the module that take the child responds with another coded signal (which identifies the child), so that if the father stops receiving the signal it is activated an alarm. This system is designed for a parent to watch up to 8 children and does not incorporate or supervise the operation of integrity or maintenance, or functions linked to a telephone interface

Another similar system is described in the Patent US 5661460. It is a proximity detection device of children, based on the emission of a signal by the element associated with the parent and receiving a response issued by the element that the child carries. The distance is determined by the phase difference between the emitted and the received signal. This system does not incorporate or supervise the operation of the integrity or maintenance, or functions linked to an interface telephone

The proximity detection system of the Patent US 5650770 is based on the issuance by one of the elements of the pair, so that the second element is only activated if you leave of receiving the signal from the first one to be sufficiently remote, initiating an alarm at that time and emitting a signal high intensity so that the first element detects its remoteness.

None of the systems described allow check the proper functioning of the elements that compose it nor ensure its integrity, and only one (US Patent 5936530) includes an ergonomic clamping system to ensure that you cannot detach from the subject to which it is fixed.

Explanation of the invention. Proximity sensing system of elements of a pair specific equipped with alarm and monitoring functionalities of maintenance, integrity and continuous operation

In general and in order to solve the problems mentioned in the previous section, the invention refers to a system formed by two independent elements (sender / receiver) that exchange encrypted and encrypted radio signals (each pair has specific keys exclusively recognizable by the elements that constitute it.). Said system allows to detect the approximation of one element of the pair with respect to the other. We call "primary" to the element of the pair that periodically emits a characteristic signal (encoded and encrypted) and "secondary" to the second element that receives and identifies the signal emitted by the primary. In the event that the decryption of the signal received and decoded by the secondary element allows the primary element to be identified as emitter thereof, the secondary element emits a second encoded and encrypted signal that when received, decoded and decrypted by the primary element allows, if it is recognized as coming from the secondary element, the activation of light, sound, mechanical vibration signals or a combination thereof, in addition the secondary element activates a communication
GSM

To the basic functionality of the system are added, In addition, the functions of integrity, maintenance, operation Continuous and communications. For this the primary elements and secondary incorporate two sensors of the battery charge in which is based its power so when these sensors provide your respective control system with signals corresponding to levels below (at) preset (s) activates either a local alarm or sending unconditionally through a telephone interface of a call or message or both. The signal encryption key encoded and encrypted feature of both elements can be renewed through a call or message received through the telephone interface of both elements.

For its part, the secondary element incorporates a fixing system (ergonomic or non-ergonomic) equipped with a integrity sensor (for example, a closure that closes a circuit electric; at the moment when the closure is broken, the circuit and this circuit opening is detected by the module control that activates the unconditional sending of a call through GSM module) which, if provided to the control system a signal indicating the violation of such integrity activates unconditional sending through a Telephone interface of a call or message. The control of continuous operation of the secondary element is possible through of the broadcast at periodic intervals and through an interface Telephone calls or messages. The emission power of Secondary element can be controlled through a call or message received through the telephone interface of both elements.

Also the primary and secondary elements incorporate two modules for receiving and / or sending voice phone calls that may be restricted to certain callers and / or recipients.

Explanation of the drawings

The invention is accompanied by a series of Drawings that illustrate the following:

Figure 1 shows a block diagram of the structure and functionalities of the invention.

The primary element (A), is formed by transmitter module (1) and radio frequency receiver (2), alarm (3), GSM telephone module (4), battery (5) and control module (6) with transmitter (7) and receiver (8) control functions, management of keys (encoding-decoding) (9, 9 '), load management (10) and alarm (11), communication with GSM (12), amplification and power control.

The secondary element (B) consists of a receiver module (2) and a radio frequency transmitter (1), alarm (3), GSM telephony module (4), integrity sensor (13), battery (5), module system control (6) with key management functions (coding-
decoding) (9, 9 '), load management (10) and alarm (11), transmitter control (7), integrity management (14) and power control (15)

And both systems interact by signal radio frequency coded and encrypted (16).

Figure 2 represents the block diagram the primary element corresponding to the practical realization of the invention. This element is composed of:

radiofrequency module (17) formed by transmitter (1), receiver (2), amplifier (18), alarm (3), battery (5), control module (6) and radio frequency antenna (19).

Figure 3 represents the block diagram the secondary element corresponding to the practical realization of the invention. Said element is composed of: radio frequency module (17), transmitter (1), receiver (2), amplifier (20), alarm (3), GSM module (4), battery (5), control module (6), antenna radio frequency (19) and GSM antenna (20.

Embodiment of the invention

The present invention is illustrated with the following example that is not limiting the scope of the invention.

A couple of elements, primary and secondary, They constitute the device. The communication between them is done through a radio frequency signal.

The main parts of the primary element are radio frequency module (19) formed by transmitter (1), receiver (2), amplifier (18), alarm (3), battery (5), control module (6) and radio frequency antenna (19) (Figure 2).

The main parts of secondary element they are radio frequency module (19), alarm (3), GSM module (4), battery (5), control module (6), radio frequency antenna (19) and GSM antenna (20) (Figure 3).

The radio frequency unit transmitter-receiver, both of the primary element and of the secondary, is based on a Motorola T5412 PMR working on Selectively in the band 446.00625 - 446.09375 MHz.

The GSM module is composed of a sub module of call control, based on a 16F876 PIC, and by one unit Siemens 35 transmitter-receiver.

The microprocessor of the control module corresponding to the "primary element" performs several functions. The first is the constant emission, with control of power not exceeding 500 mW, of 446 MHz pulses encoded in Frequency and encrypted. It is done every 10-20 seconds being the estimated duration of each signal of 120 milliseconds The second is the activation of the element of alarm, either audible or bright, after processing and identifying the signal received by the receiver of the radiofrequency module.

The microprocessor of the control module corresponding to the "secondary element" performs two functions fundamental. The first is to activate the transmitter of the radiofrequency module after processing and identifying the signal Received at the receiver. The emitted signal, in this case, is 446 MHz continuous frequency coded and encrypted. The second function, which is performed simultaneously to the previous one, consists of activating the GSM module to make a call telephone

Both the primary and secondary elements are They are powered by 9 volt batteries (6LR61).

The tests performed confirm the good device operation for distances between the two elements that vary between 500 m and 3 km.

Claims (7)

1. Proximity detection system that understands:

(TO)

a sender or primary element containing transmitter module (1) and receiver  radio frequency (2), alarm (3), GSM telephony module (4), battery (5) and control module (6) with control functions of the radio frequency emitter (7) and radio frequency receiver (8), key management (encoding-decoding) (9, 9 ''), load management (10) and alarm (11), communication with GSM (12), amplification and power control;

(B)

a receiver or secondary element containing receiver module (2) and radio frequency transmitter (1), alarm (3), GSM telephony module (4), integrity sensor (13), battery (5), module system control (6) with key management functions (encoding-decoding) (9, 9``), management of load (10) and alarm (11), radio frequency transmitter control (7), integrity management (14) and power control (15)

The sender or primary element incorporates a system for monitoring the charge of the battery that feeds it, which provides information either to activate a local alarm or to send calls or messages on mobile telephony when loads below certain predetermined thresholds are detected; The receiving or secondary element incorporates a fixing system equipped with a fixing integrity sensor and provides information for sending calls or messages on mobile telephony in the event that the fixing supervisory system detects its non-integrity; the receiving or secondary element incorporates a system of periodic emission of messages or calls through the telephone interface that allows it to control the continuous operation of the system; and the two independent elements, sender or primary and receiver or secondary, exchange coded and encrypted radio signals of each
partner. 2. Proximity detection system according to claim 1, characterized in that the encryption key of the sending or primary element and of the receiver or secondary is renewed through the reception of a mobile telephone call or message. 3. Proximity detection system according to the preceding claims, characterized in that the sending or primary element has a system for receiving, from one or several callers, voice calls over mobile telephony. 4. Proximity detection system according to the preceding claims, characterized in that the sending or primary element has a system for sending, to one or more recipients, voice calls over mobile telephony. 5. Proximity detection system according to the preceding claims, characterized in that the receiving or secondary element has a system for receiving, from one or several callers, voice calls over mobile telephony. 6. Proximity detection system according to the preceding claims, characterized in that the receiving or secondary element has a system for sending, to one or several recipients, voice calls over mobile telephony. 7. Proximity detection system, according to the preceding claims, characterized in that the transmitting power of the receiving or secondary element is modified through the reception of a mobile telephone call or message.