REMOTE INTERROGATION OF MONITORED LOCATIONS

Abstract: A remote location is monitored using sensing apparatus, such as means for detecting lighting changes or shaft rotation, the output from which is used to alter the condition of wireless communications equipment such as a cellular telephone. A central station then poles the cellular telephone apparatus and detects the condition of the telephone apparatus in order to determine the status of the remote location.

Description: 1 Remote Interrogation of Monitored Locations The present invention relates to the remote interrogation of monitored locations. There are many situations where one wishes to monitor activity or a condition at a location and be able to find out from a remote site what is happening at the location. Once such situation is where once wishes to monitor a baby in a room from a remote site. When the remote site is within the same building or very close by, then it is relatively easy to do this with either hard wired or short range radio systems. However, when the remote site is further away, it becomes more difficult. In GB 2296843, it has already been proposed to monitor a vehicle fitted with a mobile radio and to generate an alarm signal automatically from the mobile radio in response to a monitoring device sensing a change in conditions. The present invention provides a method of remotely interrogating a monitored location, comprising the steps of sensing an activity or condition at the location altering the condition of cellular telephone apparatus at the location as a result of said sensing step, interrogating the location by placing a telephone call to the telephone apparatus at the location; and registering the result of the telephone call. Using cellular telephone technology means that simple interrogation techniques can be utilized. For example, the activity or condition it is wished to monitor can be used to switch off the telephone and thus trigger the automatic response from the telephone system when one is attempting to telephone the apparatus. The present invention provides apparatus for monitoring a location comprising a cellular telephone apparatus at the location, means for detecting a 2 predetermined activity or condition at the location and control means responsive to said detecting means altering the condition of the cellular telephone apparatus, whereby to cause it to give a different indication to an incoming call in the presence of a detected activity to that when there is no such detection. Features and advantages of the present invention will become apparent from the following description of an embodiment thereof given by way of example with reference to the accompanying drawing which shows diagrammatically a location being monitored by a system utilizing conventional cellular telephone technology. There are a number of situations where a location has to be monitored in an inexpensive but reliable manner. Examples range from monitoring mobile locations such as boats and earth moving plant for theft to monitoring fixed locations such as illuminated displays and signs for a lack of illumination. All these examples have in common the lack of fixed communication lines and/or power. They are also often in positions which are not easy to access and so the possibility of passing close by at regular intervals is not feasible or practicable. Referring now to the drawing, this shows a fixed location which in this example is a display or sign 10 illuminated by a lamp 11. The illumination is being monitored by a photo detector 12 in order to detect failure of all or part of the illumination system. The way in which the detection is undertaken is not critical; it could be a photo detector or a current sensitive element in the lamp circuit. Upon detection of the predetermined condition, in this case a lamp failure, a control system 14 is activated in order to cause cellular telephone apparatus 15 to be conditioned so as to provide an appropriate indication when called from a remote site. This could be in the form of a pre-recorded message being played to a caller when the telephone is automatically answered or the fact that the cellular telephone apparatus is switched off so that the conventional 3 message is played to the caller at a base station 16. Remote monitoring can be undertaken using an operator or a computer system. The time of the interrogation can be logged and the result indicated. It will be appreciated that different levels of monitoring can be provided by utilizing the pre-recorded message for a first level and the switching off the apparatus as a second level of monitoring. The advantage of this arrangement is that the apparatus can provide monitoring of a location where one or both of power and fixed wire communications is either lacking or difficult to achieve. The telephone apparatus and/or detector can be powered by the mains, by battery or by a rechargeable battery fed from a solar cell It will be appreciated that the activity of characteristic sensor could be any suitable device or arrangement depending on the activity or characteristic to be sensed. The following things could be monitored: - Shaft rotation Pressure (air) Tachometer/proximity Air flow Float level switching Combustible gas Vibration/motion Carbon Monoxide Tilt Nitrogen oxide Hall effect Doppler-shift - counting - Intruder - ? - Proximity Piezo - Vibration - Impact -Movement - Vibration PC and peripherals (Magnetic pick-up) - Dynamic AC/DC volts amps ~ Bi-morph Ferrous/non-ferrous prox/movement - Vibration Light - Stress Temperature T° + -4°C - Acoustic

Claims: 4 CLAIMS: 1. A method of remotely interrogating a monitored location, comprising the steps of sensing an activity or condition at the location altering the condition of cellular telephone apparatus at the location as a result of said sensing step, interrogating the location by placing a telephone call to the telephone apparatus at the location; and registering the result of the telephone call. 2. A method according to claim 1, wherein the telephone apparatus is normally on but is switched off as a result of the sensing step. 3. A method according to claim 1, wherein the telephone apparatus is arranged to transmit a pre-recorded message when interrogated by the placing of a telephone call to it in the event that said sensing step detects a predetermined level activity or condition at the location. 4. A method according to claim 3, wherein the telephone apparatus is arranged to switch off in the event that said sensing step detects a level of activity different to said predetermined level. 5. Apparatus for monitoring a location comprising a cellular telephone apparatus at the location, means for detecting a predetermined activity or condition at the location and control means responsive to said detecting means altering the condition of the cellular telephone apparatus, whereby to cause it to give a different indication to an incoming call in the presence of a detected activity to that then there is no such detection.

Inventors: LEIGHTON JAMES BERNARD, LEIGHTON, JAMES, BERNARD
Applicants: LEIGHTON JAMES BERNARD, LEIGHTON, JAMES, BERNARD
Application year: 1999
Main classification: G08B25
IPC codes: G08B25, G08B26