GB2163322A - Access authorisation system - Google Patents

Abstract

An access authorisation system comprises an RF receiver transponder device, to be carried by a person attempting to gain access to a restricted access area, and an access/rerouting door device disposed at an interface between a free access area (20) and the restricted access area (21). The door device includes an entrance port (1) and an exit port (6) and means (4) disposed therebetween which prevent movement of the person between the ports except upon a favourable response of the RF receiver transponder to an RF interrogation signal launched into a volume including the movement prevention means. The movement prevention means may comprise a cylinder (4) with a single doorway (5) which can be driven into predetermined rotational positions to communicate with the entrance port (1), the exit port (6), and a rerouting exit port (8) and to adopt a position intermediate the entrance and exit ports when the doorway (5) is closed by a wall portion (12). <IMAGE>

Description

SPECIFICATION Access authorisation This invention relates to access authorisation that is to say means for identifying a person and then permitting, or otherwise, entry to a restricted access area, and to an access authorisation system.

According to the present invention there is provided an access authorisation system comprising an RF receiver transponder device and an access/rerouting door device disposed at an interface between a free access area and a restricted access area, the door device including an entrance port, an exit port to the restricted access area and means disposed between the entrance port and- the exit port preventing movement therebetween of a person carrying the RF receiver transponder device except upon a favourable response by the RF receiver transponder device to an RF interrogation signal launched into a volume including said movement prevention means.

Embodiments of the invention will now be described with reference to the accompanying drawings, in which: Fig. 1 illustrates, somewhat schematically, a plan view of an access/rerouting door device, and Fig. 2 illustrates, on a reduced scale, a view of the access/rerouting door device of Fig. 1 from the entry side thereof.

The invention is concerned with a solution to problems which arise when identification/authorisation large number of people within a short time. There should ideally be a minimum impediment to their progress during the process with extremely high long term reliability of system operation. Ideally no overt response should be required by the person to be identified, and embodiments in which no response by the person himself is required should be possible. For maximum reliability no mechanical parts should inherently be involved in the identification process.

Identification is currently achieved by a variety of means, such as cards or tickets encoded mechanically, magnetically or optically where automatic systems are in use, or specially prepared documents with or without various means of inherent identification when manual methods are employed.

The present invention basically proposes use of an RF identification process in combination with a door device permitting access to a restricted access area or causing re-routing to other areas in dependence on the result of the identification process. For utmost reliability and maximum convenience for the user it is proposed to use a miniature receiver transponder, which may be derived from the radio pager devices as disclosed in our G.B. Patent Specification No. 1517121 (1.A.W. Vance 3) and our G.E. Patent Application No.

2057520A (1.A.W. Vance 8), for example, and use frequency modulation, zero IF and digital techniques.

The miniature receiver transponder may be physically realised in the shape of a conventional credit card, but of two or three times the normal thickness, and be battery powered.

The lifetime will depend on the battery technology used and the current saving circuits adopted. For practical purposes a minimum of say three months continuous use is desirable.

The identification system preferably operates on a single input frequency with the receiver of the miniature receiver transponder being capable of receiving a limited number of codes, the most important of which causes its associated transmitter to respond with the particular one (the reply code) of a plurality of possible replies which identifies and is unique to that miniature receiver transponder, the number of possible replies being of the order of millions. The receiver technology which it is proposed to employ and as described above is such that the input frequency may be selected, without substantial technical constraint, such as to satisfy the appropriate regulatory bodies and to provide a sufficient input signal in the access/rerouting door device with which the miniature receiver transponder is to operate and which will be described in greater detail hereinafter.A single 25 kHz, and potentially even a 12.5 kHz, channel would suffice for operation on a national scale. The miniature receiver transponder device contains no moving parts with the exception of an on/off switch and those associated with a battery compartment. The reply code may be modified to indicate a tow battery volts condition which can then be used to indicate the existence of same to the user upon permitting of access to the user by the access/rerouting door device. The reply code may be so constructed that, by use of a complex arithmetical relationship, a PIN (Personal Identification Number) optionally issued with the device, can be requested for manual entry by the user at the access/rerouting door device and preferably in an covert situation.

The PIN and reply code will allow local autonomous computation. The dynamic range of the miniature receiver transponder device should be sufficient to enable satisfactory operation at a predetermined distance from the receiver transmitter elements of the access/rerouting door device so that the device may be reaonably disposed about the user. It is not required for the user to present the card device to a particular element of the access/rerouting door device, rather the latter senses the presence of the card device within a predetermined volume of the door device.

Thus clothes or pinned thereto and the user is simple required to operate the on/off switch when access is likely to be required or is not required such as at start/end of a working day. In the "on" condition the battery saving circuit generally maintains the card device in a stand-by state. As mentioned above the card device may have the capacity to recognise a limited range of incoming coded signals, and this capacity may be employed such that, for example, when in the stand-by state a particular signal may be transmitted to it as a warning that it is required for full use within a short time and serves to switch it to a "ready'' state.

An embodiment of access/rerouting door device will now be described with reference to Figs. 1 and 2. Basically it consists of a structure which reduces public access to a single line, with an optical knee-bar or other device to prevent crowding whereby only one person at a time is allowed access to an entrance area and subsequently to an identification area. In Fig. 1 an entrance port of the door device is indicated by reference numeral 1, the entrance port 1 communicating with an entrance area 3 in the form of a narrow passage with an optional knee-bar device 2 which permits entry of only one person at a time. The entrance area 3 is shown closed by a cylinder 4 containing a single doorway 5.

The cylinder 4 is balanced about a vertical axis, can be pneumatically, for example, driven to one of four pre-set positions, and is guarded by suitable sensor devices to ensure total safety of an occupant. The cylinder 4 is closed at its upper end and pivoted at dead centre. It is open at its lower end and engaged in a circular groove 41, in a fixed floor of the structure, in which it moves freely under the action of the drive means. The use of pneumatic devices for the driving of the cylinder allows positive near-silent operation with maximum reliability to be achieved. The cylinder 4 may be constructed of a tough light-weight translucent material, and contain elements substantially confining a transmitted RF field to its interior. The use of a translucent material will aid user acceptance of the door device.The structure also includes an exit port 6, comprising a narrow passage, in communication with the restricted access area and an exit port 7, comprising a narrow passage, whose actual exit 8 is shown adjacent the entrance of entrance port I and which is used to reroute persons who have been identified as not permitted access to the restricted access area. Thus on the free access area 20 side of the door device there are two doorways in the embodiment illustrated in Fig. 2, whereas on the restricted access area 21 side there is a single doorway. The free access and restricted access areas being shown separated by a wall 22.

Disposed relative to each of the three positions of the cylinder doorway in which a person can pass between the interior and exterior of the cylinder are sensors 9, 10, 11, which may be comprised, for example, of pairs of vertical sensing arrays and/or sensing pads disposed in the floor, for determining the passage of a person and acting as safety devices such that movement of the cylinder will not take place until a person has moved fully in the relevant direction between the interior and exterior of the cylinder.

The cylinder 4 will normally stand open as an extension to the entrance area 3. When it is entered by a person and with suitable indications from the safety sensor 9, it will rotate through 90 to a temporarily closed position, the doorway 5 having rotated to a point where a wall portion 1 2 of the structure effectively blocks it. It will at the same time have temporarily closed off the entrance passage or port 1, in which position it will be interlocked with the optional knee-bar or other restraining device 2. When this position is reached, an RF interrogation signal is launched into the interior of the enclosed volume (cylinder) and a miniature receiver transponder, as described above, carried by the person will respond thereto.If the response is satisfactory the cylinder will rotate a further 90 , thus allowing effective straightthrough access to the restricted access area via exit port 6. In the case of an unsatisfactory response the cylinder will instead rotate through 180 allowing access to the rerouting exit port 7. Rotation in either direction is possible for the 180 turn, although from a security point of view rotation in the direction back through the entrance port/cylinder doorway interface is preferable. The exit port 7 may be to an area other than that from which the door device was entered, so that a person who is rerouted may lead directly to other methods for gaining authorisation for access to the restricted access area.If an authorised access person is so rerouted then this may serve as an indication of malfunction of his receiver transponder. Having sensed departure of a person from the cylinder towards exit port 6 or exit port 7 the cylinder is then rotated through a further 180 or 90 , as appropriate, to realign the cylinder for the entrance of another person through entrance port 1. Typically the cyliner should be able to perform a complete rotation within one second in order to ensure a minimum impediment to the free flow of people through the structure. However, the actual rate of passage is to a great extent determined by the speed with which people actually enter and leave the cylinder and the speed with which this is sensed by the sensor arrays. The dimensions of the structure as a whole should be such as to allow a sufficient size of the cylinder to cater for worst case conditions. The doorways 5 and the communicating structure ports are typically of the order of 2 feet (60cm) in width, and the cylinder 4 has an external diameter of the order of 3 feet (90cm). The door device is "fail safe" so that if the operating power should disappear for any reason, then the cylinder will be capable of manual rotation from inside, but preferably not in a direction to communicate doorway 5 with exit port 6.

If PIN identification is also required as an additional security measure, then a person attempting to gain access to the restricted access area will be requested manually to insert his personal identification number. This request will occur after the first 90 rotation of the cylinder following entry thereto, by the revealing of a suitable mechanism 23 for insertion of the PIN number in the wall portion 1 2 of the structure which is then blocking the doorway of the cylinder. The PIN number will therefore be entered under conditions of complete privacy.

The walls of the rotating cylinder may be equipped for the display of messages such that, for example the entry into, and the identification of a particular person in, the cylinder causes a message destined for that person to be displayed. Alternatively, a simple indicator in the cylinder may be employed to draw attention to the fact that such a message is displayed at area 1 3 adjacent the exit area of the structure leading to the restricted access area. One such message may be the need to change batteries and a battery exchange facility may be arranged at area 1 3.

In cases where the card device is generally on stand-by when switched "on", a signal to switch it to full use operation may, for example, be directed into the entrance area upon sensing of a person therein, for example, by a floor disposed sensing pad, whereas a signal to switch it back to stand-by may be similarly directed into the exit areas preceding exit ports 6 and 7, or directed into the cylinder itself upon completion of the interrogation/identification process.

In cases where it is not possible physically to constrain the interrogating RF field in a cylinder then the following system may be employed. For the purpose of discussion of the alternative system the space including and surrounding the door device, for example a turnstile, etc is considered as comprising (i) a hypothetical cylinder volume enclosing the turnstile ("a working area") and (ii) the adjacent volumes leading to and from it. The aerials necessary will thus include a highly directive array with similar vertical and horizontal lobes illuminating the turnstile, which will be substantially non-reflective at the chosen radio frequency. This array will thus provide the required interrogation /identification request signal equivalent to "TRANSIT, WHO?". Two further directional arrays will illuminate the areas leading to and from the "working area".This signal may optionally contain a preamble signal and will achieve a higher field strength than that present in the "working area". This will allow the FM "capture effect" to operate in favour of the "preamble" signal except in the immediate working area" where the captive effect will operate in favour of the "TRANSIT, WHO?" signal. This effect may be optionally enhanced by passive elements disposed in an appropriate fashion within the "working area".

Facilities may additionally be provided to enable the RF identification process and the associated access/rerouting door device to be operated within a spatially distributed network. Thus the equipment necessary for the RF identification process and the door device, or groups of such equipment, may be equipped with micro-processor controlled memory and communication access equipment (an intelligent terminal), nominally operating over the public switching network, and originating or receiving calls from a central data base at infrequent intervals. This terminal may hold lists of invalid identifier codes, together with details of each valid use and, optionally, messages for specific persons; each within appropriate memories. The "valid use" information may be transmitted to the central data base at intervals.Associated with this "intelligent terminal" will be the transmitter/receiver (one per door device) responsible for the generation of the small range of standard "TRANSIT, WHO?" enquiries and capable of receiving the appropriate responses for retention by the local memory, together with appropriate aerials for the RF activity within the volume.

Whereas in the embodiment described with reference to Figs. 1 and 2 a separate port is provided for rerouting, which separate port aids the rate at which people can be processed through the device, an embodiment without such a separate port can be envisaged. In that case an unfavourable response to the RF interrogating signal results in the cylinder rotating back through 90 to open its doorway to the entrance port again. Alternatively the control for the cylinder drive means may be arranged such that the cylinder only moves to a position permitting access to the restricted access area exit port when a favourable response has been received, at all other times it being open to the entrance port. In this latter case physical constraint of the RF field will not be provided by the cylinder since interrogation will take place with the door open and thus aerial systems based on that described above for instances of lack of physical constraint of the RF field will be required.

Claims (14)

1. An access authorisation system comprising an RF receiver transponder device and an access/rerouting door device disposed at an interface between a free access area and a restricted access area, the door device including an entrance port, an exit port to the restricted access area and means disposed between the entrance port and the exit port preventing movement therebetween of a person carrying the RF receiver transponder device except upon a favourable response by the RF receiver transponder device to an RF interrogation signal launched into a volume including said movement prevention means.

2. An access authorisation system as claimed in claim 1, wherein the movement prevention means includes a cylinder, disposed with its longitudinal axis vertical, rotatable about its longitudinal axis into a plurality of predetermined rotational positions by cylinder drive means, the cylinder having a single doorway in its circumference which in a first rotational position of the cylinder communicates with the entrance port and in a second rotational position of the cylinder communicates with the exit port.

3. An access authorisation system as claimed in claim 2, including a third rotational position of the cylinder, disposed between said first and second rotational positions, in which the cylinder doorway is closed, and means for sensing when a person has entered the cylinder from the entrance port and causing the cylinder to be driven to the third rotational position, said RF interrogation signal being launched into the cylinder when the latter is in the third rotational position.

4. An access authorisation system as claimed in claim 3, wherein in the third rotational position of the cylinder, means are revealed to the person for the entry of a personal identification number.

5. An access authorisation system as claimed in claim 3 or claim 4, wherein in the third rotational position of the cylinder, message display or indication means are displayed to the person.

6. An access authorisation system as claimed in any one of the preceding claims, wherein the RF receiver transponder is configured as a card-like element and is battery powered.

7. An access authorisation system as claimed in any one of the preceding claims, wherein the RF receiver transponder and means launching said RF interrogation signal operate on a single frequency and employ frequency modulation, zero IF and digital techniques.

8. An access authorisation system as claimed in claim 6 as appendant to claim 5, wherein low battery power is indicated on the message display or indication means.

9. An access authorisation system as claimed in claim 2, wherein when said cylinder rotates to the second rotational position sensing means associated with the exit port serve to detect the exiting of the person from the cylinder and cause the cylinder to be rotated to its first rotational position.

10. An access authorisation system as claimed in claim 2 including an entrance hall leading from the entrance port to the cylinder and a restraining device disposed in the entrance and interlocked with the operation of the cylinder whereby to prevent the passage of a person through the entrance hall except when the cylinder is in its first position.

11. An access authorisation system as claimed in claim 2 and including a further exit port and a corresponding rotational position of the cylinder, which further exit port is not in communication with the restricted access area and wherein upon an unfavourable response of the RF receiver transponder to the RF interrogation signal the cylinder is driven to the rotational position corresponding to the further exit port whereby the person in the cylinder is rerouted.

1 2. An access authorisation system as claimed in claim 6 as appendant to claim 2, wherein the RF receiver transponder includes an ON/OFF switch, employs battery saving techniques and is normally in a stand-by state when the switch is in the ON position, wherein prior to entering the cylinder an RF signal launched into the entrance port serves to switch the RF receiver transponder to a full operation state, and wherein after exiting from the cylinder an RF signal launched into the exit port serves to return the RF receiver transponder to the stand-by state.

1 3 An access authorisation system as claimed in claim 1, wherein the RF interrogation signal is launched from an aerial system including a highly directive array illuminating said volume including said movement prevention means for launching said RF interrogation signal, and respective further directional arrays illuminating said entrance and exit ports.

14. An access authorisation system as claimed in claim 13, wherein said further directional arrays launch signals containing a preamble signal and achieve a higher field strength than said highly directive array, whereby the FM captive effect operates in favour of the preamble signal except in the vicinity of the movement prevention means where it operates in favour of the RF interrogation signal.

1 5. An access authorisation system as claimed in claim 1 and substantially as herein described with or without reference to the accompanying drawings.

1 6. An access authorisation system substantially as herein described with reference to the accompanying drawings.