WO2013050993A1

WO2013050993A1 - Radio location system

Info

Publication number: WO2013050993A1
Application number: PCT/IE2011/000055
Authority: WO
Inventors: Trevor SHIER; Steven RADLEY; Paul MOYLETT
Original assignee: Pst Innovation Limited
Priority date: 2011-10-04
Filing date: 2011-10-04
Publication date: 2013-04-11

Abstract

The invention provides a radio location system consisting of a master transceiver unit worn or attached to an object. A remote transceiver is used to locate the master transceiver unit. The master transceiver unit can be programmed to generate a unique signal, to prevent its output from being received by another transceiver, and therefore communicates to the exclusion of all other transceivers that are operational within the vicinity of the master transceiver unit, the same applies to software. The signal from the master transceiver unit is received by the remote transceiver, thereby indicating height, direction and positioning from which the radio signals emanate. When the remote transceiver is within a predetermined distance of the master transceiver unit, the master transceiver unit alerts the remote transceiver that the object is very close.

Description

Radio Location System

Description

This invention relates to radio location and in particular to a system for providing a portable master unit with its direction and range to a linked transponder.

Many prior art publications are concerned with the location of people or items of value or importance.

The master unit uses a number of different types of radio technologies incorporated within it, to assist in its own location, for example, WiFi, Bluetooth, GPS or any other forms of wireless technologies.

The master unit will communicate with the following devices, for example; personal computers, portable computing devices, portable communication devices, subscriber devices or units, and personal digital assistants. The devices, also referred to as, "portable communication devices" and "communication devices" can include all such devices and equivalents, and are not limited to communication devices that are wireless. The communication link supports the transfer of information including voice and data signals between the mobile devices and the service provider systems and via at least one of wireless couplings, using one or more communication protocols known in the art.

Owing to the complication and poor performance of the prior art arrangements, however, there remains a requirement for a simple, economical, lightweight and reliable location system. Further more it would be advantageous for such a system not to be restricted to locating transponders within particular sectors.

The present invention provides for such a required location system by replacing complicated features with simplified and robust and novel arrangements.

In accordance with the invention there is provided, a radio location as set out in the appended claims. In this embodiment a remote unit is linked via a radio frequency transmission with the master unit whose direction and range with respect to the remote unit is determined.

The master unit responds to a signal from the remote unit. These signals from the master unit are referred to herein as polling signals and are addressed to a remote unit in expectation of a reply from the master unit.

Both the master and the remote unit are equipped with the relevant radio interfaces within the relevant frequency spectrum bands.

The radio frequency transmissions from both the master and remote unit are omni-directional, similarly the reception.

The master unit assesses the range of the remote unit by monitoring the information from the remote unit concerning the received signal strength measurement, i.e. the strength of the signal from the remote unit when received by the master unit.

By monitoring of the apparent received signal strength from remote unit, the master unit can increase or decrease the transmit power on Bluetooth and WiFi by monitoring the signal strengths corresponding to the separation of the transmitter to the receiver. A relative location of the remote unit is obtainable.

These results are achievable notwithstanding the effects of reflection, path attenuation and other propagation problems.

Providing just the general direction is often extremely useful so that the remote unit can quickly determine direction of the master unit.

Using the compass module on the master unit the information is then computed and can then be displayed on the remote unit.

Another means of indicating simply the general direction and distance of the remote unit is by the use of the master unit's GPS module which is fitted in it, this information is then sent to the remote unit, this information is then decoded by a software application on the remote unit giving the direction of the master unit.

Data transmission to the remote unit will be Compass data, and or GPS data, and or supervisory data sets.

The approximate range (i.e. near or far) is obtained by attenuating the power level on the master unit, should the unit fail to communicate with the remote unit. The master unit will then increase the transmit power; it would then try again to communicate with remote unit. If that fails the master unit switches to WiFi to establish communication link. The master unit will then send either or both the compass data and GPS data and send this to the remote unit. Should this communication fail, the optional RF module, if fitted, would try to establish a connection and once again the master unit will send either or both compass, height and GPS data to a suitably equipped remote unit.

Out of Range Mode

If, after a predetermined number of polling signals, the master unit fails to receive a valid acknowledgement from the remote unit then an emergency condition is adopted.

A sequence of events is initiated at the master unit in order that the remote unit can be located. The sequence starts with the master unit transmitting an activate command on high power, on either Bluetooth or WiFi. On receipt of an active command the master unit can activate an audible command that can be used to locate its presence.

If the master unit loses communication, and cannot detect the presence of the remote unit within a predetermined time period, the master unit will adopt an emergency condition.

The master unit will under these conditions trigger an alarm and/ or emit a high power RP distress signal autonomously on Bluetooth, WiFi, or optional RP module if incorporated.

The master unit continuously switches between WiFi and Bluetooth until it locks to the strongest signal on remote unit. The master unit then assesses the received signal and adopts the relevant wireless technology. It then either increases or decreases the power depending upon the mode of transmission used. This can then be displayed on the screen of remote unit. Once again if the master unit fails to communicate with Bluetooth or WiFi, then data can be transmitted via the optional RF module, if incorporated.

In this embodiment the master unit is wireless. The master unit has a unique pre-programmed identity (ID) and is transmitted to the remote unit within the signalling from the master unit. The remote unit also has unique ID recognisable by the master unit. This is linked to the software application on the remote unit.

The master unit will recognise the unique ID of the remote unit. Messages from the master unit comprise of an ID, to denote the type of unit, master or remote, also an instruction for power level that the remote unit is to use for subsequent transmissions, and the mode in which the remote unit needs to adopt. The master unit will only respond to messages from the remote unit's that the software is paired with.

On power-up of the master unit, a search is performed during the initialisation process for any other master units. If any additional master units are found, the master unit, which is paired with the remote unit, will then try to establish a communication link with the additional master unit using the relevant wireless technologies.

Once the communication has been established with the additional master unit, the information relating to the additional master unit is transmitted to the remote unit. In the same instance both master units can communicate with each other and transmit this information to the remote unit, as each master unit has a unique identifier. Each master unit can give a direction, from each Other and from the remote unit. However, the pairing process is only adopted during the first initialisation sequence. Each master unit has a unique identifier. The selection of the master unit causes it to be tethered to the remote unit and communication link is subsequently maintained between the master unit and the remote unit.

Whilst the link is maintained, (tethered) the remote unit is periodically polled by the master unit, messages are then sent to the remote unit, including its battery state and power levels, in addition power threshold levels. When it appears that the master unit is approaching threshold limits the master unit changes the Bluetooth power level, or changes to WiFi. Additionally the master unit may increase the polling rate, as this will provide an out of range condition more quickly. It may occur sometimes that the master unit loses the wireless link with the remote unit. The master unit will automatically switch to high power Bluetooth or switch to WiFi to re-establish the link with the remote unit.

When the master unit has re-established the link to the remote unit the threshold levels on the remote unit can be changed using the software application.

The processing for both the master unit and remote unit may be implemented as hardware or as software for which an operating system may or may not be employed.

Claims

Radio Location System Claims

1. A system for locating the master unit linked by a radio transmission to a remote unit, and displaying the location of the master unit on the remote unit as to the location of the master unit, via Bluetooth 101, WiFi 102 and any other form of RF modules 103 technologies, with GPS 104 and or Compass 105 that gives height and direction of the master unit that will be displayed on the remote unit via a software application.

2. A system as claimed in claim 1 in which different wireless technologies have been utilised. A system claimed wherein the master unit may communicate with a fixed device which includes at least one of; personal computing devices, portable telephones, portable communication devices, subscriber devices or units, and personal digital assistants.

3. A system as claimed in any proceeding in which the master unit signal power is proportional to the signal strength of the polling emission received at the transponder.

4. A system as claimed in any preceding claim in which distance of the remote unit from the master unit is determined from the signal strength, polling signal when received by remote unit.

5. A system as claimed in any preceding claim in which an emergency condition is adopted with respect to a particular remote unit when the loss of the radio link between the remote and the master unit is detected.

6. A system as claimed in 5 in which the response to an emergency condition is a high power signal from the master unit. To activate either Bluetooth or WiFi on the remote unit, this shall be controlled via a software application on the remote unit, unless the remote unit cannot communicate with the master unit at all.

In this instance a Telemetry transmission mode will be initiated from the master unit if fitted, this transmits on a specified frequency. Alternatively, transmits or sends a predefined message to a pre designated device or location if the relevant module is fitted.

7. A system as in claim 5 in which the response to an emergency condition is an alarm autonomously activated by the remote unit.

8. A system as claimed in 1 for locating the master unit linked by a radio transmission to a remote. The reverse will also apply in this instance, as the remote unit can become the master unit by utilising the different wireless technologies within the following: personal computing devices, portable telephones, portable communication devices, subscriber devices or units, and personal digital assistants, wherein the master unit may communicate with a fixed device or devices or remote units utilising the same technologies in the remote unit, WiFi, Bluetooth, GPS, Telemetry, GPRS, GSM, CDMA, WCDMA, UMTS.

9. A system substantially as hereinbefore describe with relation to or as illustrated in the accompanying Figure 1.

An embodiment of the invention will now be described with reference to the Figure 1 in which like numerals are applied to the identical features.

While this disclosure has described certain embodiments and generally associated methods, alterations and permutations of these embodiments and methods will be apparent to those skilled in the art. Accordingly, the above description of example embodiments does not define or constrain this disclosure. Other changes, substitutions, and alterations are also possible.