Abstract:
Bringing one radio communication device into a predetermined close physical relationship with another radio communication device, indicates an intent for radio communication to occur between the devices. The predetermined physical relationship may involve the alignment of the devices, the attraction of the devices together so that they touch or physical separtion of less than a few centimetres. Sensing means may be used for sensing the predetermined physical relationship.

Description:
BACKGROUND OF THE INVENTION  
         [0001]    A radio communication device is typically capable of communicating with any one of a plurality of other radio communication devices (receivers, transmitters or transceivers) which are within range. Consequently, at any time the radio communication device may be capable of communicating with a large number of other devices. If a user of the radio communication device wishes to communicate with a specific one of the plurality of devices within range, it may be difficult for the user to ensure that he or she is communicating with the correct device.  
           [0002]    It would be desirable to allow a user to ensure that he or she is communicating with the intended device.  
         BRIEF SUMMARY OF THE INVENTION  
         [0003]    In embodiments of the invention, bringing one radio communication device into a predetermined close physical relationship with another radio communication device, indicates an intent for radio communication to occur between the devices.  
           [0004]    In one embodiment, the predetermined physical relationship involves the alignment of the devices and a communication device may have alignment means for aligning it with another communication device. The alignment means may be a part of a replaceable cover.  
           [0005]    In another embodiment, the predetermined physical relationship involves the attraction of the devices together and a communication device may have attraction means for attracting it to another communication device so that the devices touch. The attraction means may be a part of a replaceable cover.  
           [0006]    In another embodiment, the predetermined physical relationship involves physical separtion of less than a few centimetres, but does not include separation of many metres, and a communication device may have a mode in which it is capable of communicating only a few centimetres.  
           [0007]    In other embodiments of the invention, a communication device comprises sensing means for sensing the existence of a predetermined physical relationship between it and another communication device and control means for controlling it to communicate with the sensed communication device. The sensing means may be a part of a replaceable cover.  
           [0008]    The radio communication devices may be transmitters, receivers or transceivers.  
           [0009]    For a better understanding of the present invention reference will now be made by way of example only to the accompanying drawings. 
       
    
    
     BRIEF DESCRIPTION OF SEVERAL VIEWS OF THE DRAWINGS  
       [0010]    [0010]FIG. 1 illustrates an arrangement of low power radio frequency transceivers;  
         [0011]    [0011]FIG. 2 schematically illustrates a first embodiment of the present invention;  
         [0012]    [0012]FIG. 3 schematically illustrates one possible implementation of the sensors of the first embodiment;  
         [0013]    [0013]FIG. 4 illustrates a second possible implementation of the sensors of the first embodiment;  
         [0014]    [0014]FIG. 5 schematically illustrates a third possible implementation of the sensors of the first embodiment;  
         [0015]    [0015]FIG. 6 schematically illustrates a second embodiment of the present invention;  
         [0016]    [0016]FIG. 7 is a flow diagram illustrating the method of the present invention;  
         [0017]    [0017]FIG. 8 is an embodiment in which the radio transceiver devices has a functional replaceable cover. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0018]    The following detailed description will describe in detail how a user can insure that a radio communication device is communicating with the intended one of a plurality of radio communication devices. In the following examples, radio transceiver devices will be used as exemplary radio communication devices. However, it should be borne in mind that embobiments of the invention additionally relate to: communication between a radio receiver device and one of a plurality of radio transmitter and/or radio transceiver devices; communication between a radio transmitter device and one of a plurality of radio receiver and/or radio transceiver devices; communication between a radio transceiver device and one of a plurality of radio transmitter and/or radio transceiver devices; communication between a radio transceiver device and one of a plurality of radio receiver and/or radio transceiver devices.  
         [0019]    [0019]FIG. 1 illustrates an arrangement  1  of radio transceiver devices  2   1 ,  2   2 ,  2   3 ,  2   4 ,  2   5 ,  2   6  and  2   7  The figure also illustrates the communication range  4   1  of the radio transceiver device  2   1 . The radio transceiver device  2   1  can communicate wirelessly with the plurality of radio transceiver devices  2   2 ,  2   3 ,  2   4 ,  2   5  and  2   6  which lie within the sphere  6   1  which is centred on the radio transceiver device  2   1  and has a radius defined by the communication range  4   1 . The radio transceiver device  2   7  lies outside the circle  6   1  and it cannot communicate with the radio transceiver device  2   1 . The radio transceiver devices  2   n  illustrated in FIG. 1 are low power transceiver devices, such as Bluetooth (trade mark) devices. Consequently, the communication range  4   1  of the radio transceiver device  2   1  has a magnitude of a few meters to a few tens of meters.  
         [0020]    [0020]FIG. 2 illustrates the radio transceiver device  2   1  in more detail. It also illustrates another radio transceiver device  2   2  which has been brought into a predetermined intimate physical relationship with the radio transceiver device  2   1 . The radio transceiver device  2   1  comprises low power radio transceiver circuitry  10   1 , a memory  12   1 , a processor  14   1  and sensor circuitry  16   1 . The processor  14   1  is electrically connected to each of the low power radio transceiver circuitry  10   1 , the memory  12   1  and the sensor circuitry  16   1  and is able to send and receive signals along each of these connections. The second radio transceiver device  2   2  comprises low power radio transceiver circuitry  10   2 , a memory  12   2 , a processor  14   2  and sensor circuitry  16   2 . The processor  14   2  is electrically connected to each of the low power radio transceiver circuitry  10   2  the memory  12   2  and the sensor circuitry  16   2  and is capable of transmitting and receiving signals along each of these electrical connections. The low power radio transceiver circuitry  10   1  and the low power radio and transceiver circuitry  10   2  are capable of communicating with each other according to a predetermined communication protocol, preferably, that prescribed by the Bluetooth (trade mark) standard. The processor  14   1  controls the low power radio transceiver circuitry  10   1 . The processor  14   1  provides a packet of data to the low power radio transceiver circuitry  10   1  for transmission. The packet data provided includes a header which comprises the identity of the intended destination of the transmitted packet. In the example of FIG. 2, the header will identify the second radio transceiver device  2   2  using, for example, its Bluetooth address.  
         [0021]    Consequently, before the radio transceiver device  2   1  can start radio communication with the second radio transceiver device  2   2 , it must identify that device so that any future radio communications can use the correct identity of that device in the header of the data packets transmitted. The sensor circuitry  16   1  detects whether or not there is a radio transceiver device in a predetermined intimate physical relationship with the radio transceiver device  2   1  and identifies the detected device. The identification of the device may occur automatically, that is without user intervention, after the existence of the predetermined intimate physical relationship has been sensed. The sensor circuitry  16   1  of the radio transceiver device  2   1  interacts  18  with the sensor circuitry  16   2  of the second radio transceiver device  2   2  to perform the detection and identification.  
         [0022]    [0022]FIG. 3 schematically illustrates a first embodiment of the sensor circuitry  16   1  of the radio transceiver device  2   1 . The sensor circuitry  16   1  comprises a permanent magnet  20  which is positioned at or close to the surface of the radio transceiver device  2   1 . The magnet  20  is a bar magnet with a north pole and a south pole. A first wire coil  22  surrounds the north pole of the magnet  20  and a second wire coil  24  surrounds the south pole of the magnet  20 . The first wire coil  22  and the second wire coil  24  are both separately connected to detector circuitry  26  and to drive circuitry  27 . Control circuitry  28  is connected to both the detector circuitry  26  and the drive circuitry  27  and has an interface to the processor  14   1 . Also illustrated in the Figure is the sensor circuitry  16   2  of the second radio transceiver device  2   2 . The sensor circuitry  16   2  comprises a permanent bar magnet  30  having a north pole and a south pole. A first wire coil  32  surrounds the south pole and a second wire coil  34  surrounds the north pole. The bar magnet  30  is positioned at or close to the surface of the second radio transceiver device  2   2 . The first wire coil  32  and the second wire coil  34  are both connected to detector circuitry  36  and to drive circuitry  37 . Control circuitry  38  is connected to the drive circuitry  37  and to the detector circuitry  36  and has an interface to the processor  14   2 .  
         [0023]    In the Figure, the bar magnet  20  of the sensor circuitry  16   1  has its north pole at or close to the surface of the radio transceiver device  2   1 . The bar magnet  20  may be mounted for rotation R so that either its north pole or its south pole is at or close to the surface of the radio transceiver device  2   1 . The south pole of the bar magnet  30  of the sensor circuitry  16   2  is at or close to the surface of the second radio transceiver device  2   2 . When the south pole of the magnet  30  is brought close to the north pole of the magnet  20  the inductance of the first coil  22  changes. This change in the inductance of the first coil  22  is detected by detector circuitry  26  which informs the control circuitry  28 . Likewise, the inductance of the first coil  32  of the sensor circuitry  16   2  also has a change in its inductance which is detected by the detector circuitry  36  which in turn informs the control circuitry  38 . The control circuitry  38  then controls the drive circuitry  37  to modulate a current in the first coil  32 . The modulating current in the first coil  32  induces an equivalently modulating current in the first coil  22  of the sensor circuitry  16   1 . The detector circuitry  26  detects the modulation of the induced current. In this way, the control circuitry  38  of the sensor circuitry  16   2  can transfer data identifying the second radio transceiver device  2   2  to the radio transceiver device  2   1 . The detector circuitry  26  obtains the identity of the second radio transceiver device  2   2  and provides it to the control circuitry  28  which in turn provides it to the processor  14   1 . The processor  14   1  on receiving the identity of the second radio transceiver device  2   2 , controls the low power radio transceiver circuitry  10   1  to transmit packets to the low power radio transceiver circuitry  10   2  of the second radio transceiver device  2   2  using radio packets having a header comprising the identity of the second radio transceiver device  2   2 . The control circuitry  28  of the sensor circuitry  16   1  can then, via the drive circuitry  27 , modulate a current in the first coil  22  and thereby transfer its identity to the second radio transceiver device  2   2 .  
         [0024]    When the second radio transceiver device  2   2  is brought into the predetermined intimate physical relationship with the radio transceiver device  2   1  the north pole of the permanent magnet  20  attracts the south pole of the permanent magnet  30  and the two devices are drawn together. The user of the radio transceiver device  2   1  consequently feels an attractive force between the two devices which provides a positive physical feedback thereby indicating to the user that it is communicating with the second radio transceiver device  2   2 . Preferably, the north pole of the permanent magnet  20  is exposed at the surface of the radio transceiver device  2   1  and the south pole of the permanent magnet  30  is exposed at the surface of the second radio transceiver device  2   2 . When the radio transceiver devices are brought together, the north pole of the magnet  22  is drawn into a touching relationship with the south pole of the magnet  30 . When the magnets  20  and  30  abut there is a satisfying contact noise which also provides a feedback to the user of the radio transceiver device  2   1 .  
         [0025]    [0025]FIG. 4 illustrates a second embodiment of the sensor circuitry  16   1 . The sensor circuitry  16   1  comprises a ferro-magnetic core  40  which is close to or at the surface of the radio transceiver device  2   1 . The ferro-magnetic core  40  is surrounded by a wire coil  42  which is connected to drive circuitry  44 . The drive circuitry  44  receives an input from control circuitry  48  and provides an output to detect circuitry  46 . The detect circuitry  46  provides an output to the control circuitry  48  which has an interface to the processor  14   1 . Also illustrated is the sensor circuitry of the second radio transceiver device  2   2  this sensor circuitry  16   2  comprises a ferro-magnetic core  50  which is at or close to the surface of the second radio transceiver device  2   2 . The wire coil  52  surrounds the ferro-magnetic core  50  and is connected to drive circuitry  54 . Control circuitry  48  provides an input to the drive circuitry  44 . The drive circuitry  44  provides an output to detect circuitry  46 . Detect circuitry  46  provides an output to control circuitry  48  which has an interface to the processor  14   2 .  
         [0026]    The wire coil  42  is energised by the drive circuitry  44  and consequently while the wire coil  42  is energised the ferro-magnetic core  40  operates as a magnet with a north pole and a south pole. In the same way, the drive circuitry  54  energises the wire coil  52  surrounding the ferro-magnetic core  50 . While the wire coil  52  is energised the ferro-magnetic core  50  operates as a bar magnet with a north pole and a south pole. When the portion of the ferro-magnetic core  40  at or close to a surface of the radio transceiver device  2   1  acts as a north pole and a portion of the ferro-magnetic core  50  at or close to the surface of the second radio transceiver device  2   2  acts as a south pole, the radio transceiver device  2   1  and the second radio transceiver device  2   2  are attracted towards each other into a predetermined intimate physical relationship. This intimate physical relationship causes the inductance of the wire coil  42  to change which is detected by the detection circuitry  46 . The drive circuitry  54  of the second radio transceiver device  2   2  under the control of the control circuitry  58  can modulate the current in the wire coil  52  and therefore modulate the effective inductance of the wire coil  42 . The modulation of the effective inductance of the wire coil  42  is detected by detection circuitry  46 . In this way, the second radio transceiver device  2   2  can transfer to the radio transceiver device  2   1  its identity. The detection circuitry  46  determines the identity of the device to which the radio transceiver device  2   1  is in an intimate physical relationship and provides this information to the control circuitry  48  which in turn provides it to the processor  14   1 . Consequently, the processor  14   1  is capable of controlling the low power radio transceiver circuitry  10   1  to communicate with the low power radio transceiver circuitry  10   2  of the second radio transceiver device  2   2 .  
         [0027]    It will therefore be appreciated that in the embodiment described in FIGS. 3 and 4, the sensor circuitry  16   1  and the sensor circuitry  16   2  have corresponding magnetic circuits. When the second radio transceiver device  2   2  is brought into a predetermined intimate physical relationship with the radio transceiver device  2   1 , the magnetic circuit of the sensor circuitry  16   2  affects the magnetic circuit of the sensor circuitry  16   1 . The effect that one magnetic circuit has on the other can be used to identify that the devices are in the predetermined intimate physical relationship and also to transfer between the devices their identification data.  
         [0028]    In FIG. 4, after the data transfer has taken place, the current in the wire coil  42  can be reversed to repel the two devices thereby indicating to the user that the data transfer has ended.  
         [0029]    In FIG. 4, as in FIG. 3, there is a positive physical feedback to the user which includes the physical attraction between the two devices and if the ferro-magnetic cores  40  and  50  are exposed the sound of their touching.  
         [0030]    [0030]FIG. 5 illustrates a third embodiment of the sensor circuitry  16   1 , and the sensor circuitry  16   2 . The radio transceiver device  2   1  has an outer surface  60  in which there is a groove  62 . The groove  62  is defined by first and second side walls  63  and  64  and a bottom wall  65 . The second radio transceiver device  2   2  has an outer surface  70  having a tongue  72 . The tongue  72  is defined by first and second side walls  73  and  74  and a top wall  75 . The tongue  72  and the groove  62  are dimensioned so that they fit snugly together. The bottom wall  65  of the groove  62  has an electrical contact  66  and the top wall  75  of the tongue  72  also has an electrical contact  76 . When the second radio transceiver device  2   2  is brought into a predetermined intimate physical relationship with the radio transceiver device  2   1  the tongue  72  engages the groove  62  and the electrical contact  66  makes contact with the electrical contact  76 . Furthermore, the engaging of the tongue and groove gives the user of the radio transceiver device  2   1  a physical feedback indicating their engagement.  
         [0031]    Referring to FIG. 5, the electrical contact  66  is connected to drive circuitry  67  and detect circuitry  68  which are in turn connected to control circuitry  69  which has an interface to the processor  14   1 . The electrical contact  76  is connected to detect circuitry  78  and drive circuitry  77  which in turn are connected to control circuitry  79  which has an interface to the processor  14   2 . The detect circuitry  68  of the radio transceiver device  2   1  detects when contact is made between the electrical contact  66  and the electrical contact  76 . The drive circuitry  77  communicates the identification data of the second radio transceiver device  2   2  to detection circuitry  68  which in turn provides it to the control circuitry  69  which in turn provides it to the processor  14   1 . The drive circuitry  67  of the radio transceiver device  2   1  provides the identity of the radio transceiver device  2   1  to the second radio transceiver device  2   2  via the detection circuitry  78  and control circuitry  79 . The radio transceiver device  2   1  may additionally have feedback circuitry  61  as part of or separate from (but connected to) the sensing circuitry  16   1 . The feedback circuitry  61  provides a feedback signal to the user indicating that the identity of the second radio transceiver device  2   2  has been successfully received. The feedback circuitry  61  may for example provide a message on the display, make a noise or cause the radio transceiver device  2   1  to vibrate.  
         [0032]    [0032]FIG. 6 illustrates a second embodiment of the present invention. The radio transceiver device  2   1  comprises low power radio transceiver circuitry  10   1 , a memory  12   1 , a processor  14   1 , sensor circuitry  16   1  and feedback circuitry  18   1 . The second radio transceiver device  2   2  comprises low power radio transceiver circuitry  10   2 , a processor  14   2  and a memory  12   2 . The processor  14   1  is electrically connected to each of the low power radio transceiver circuitry  10   1 , the memory  12   1  and the sensor circuitry  16   1  and it is capable of transmitting and receiving signals to each of these. The sensor circuitry  16   1  is additionally connected to the low power radio transceiver circuitry  10   1  and to the feedback circuitry  18   1 .  
         [0033]    In this embodiment, the low power radio transceiver circuitry  10   1  has two modes of operation. In a normal mode of operation it operates to communicate with other devices over a range of a few metres or a few tens of metres. In a second reduced power mode of operation it is capable of only communicating with a device over a few centimetres or tens of centimetres. The second reduced power mode of operation is entered in response to a user&#39;s input command. In this embodiment, the predetermined intimate physical relationship between the radio transceiver device  2   1  and the second radio transceiver device  2   2  is that they are brought within a distance of a few centimetres or a few tens of centimetres from each other such that the low power radio transceiver circuitry  10   1 , when in its low power mode, can communicate with the low power radio transceiver circuitry  10   1  of the second radio transceiver device  2   2 . If the low power radio transceiver circuitry  10   1  in its low power mode is capable of communicating with the second radio transceiver device  2   2  this indicates that the devices are in the predetermined intimate physical relationship and the necessary identification data can be transferred between the low power radio transceiver circuitry  10   1  and  10   2 . The sensor circuitry  16   1  is connected to the low power radio transceiver circuitry  10   1  and detects when the circuitry has received identification data of the second radio transceiver device  2   2 . In response thereto, the sensor circuitry  16   1  enables the feedback circuitry  18   1 . The feedback circuitry  18   1  may provide a visual indication on the display, an audio output or it may cause the radio transceiver device  2   1  to vibrate.  
         [0034]    [0034]FIG. 7 illustrates a method of transmitting data from a first radio communication device to an intended second radio communications device. The first and second radio communication devices are brought into a predetermined close physical relationship. At step  100  the first radio communication device detects a proximal radio communication device in a predetermined physical relationship to it. Preferably, the first radio communication device automatically, that is without user intervention, moves to step  102 . At step  102  the first radio communication device automatically determines the identity of the proximal radio communication device. At step  104  the first radio communication device transmits data by radio to the second (proximal) radio communication device using its previously acquired identity.  
         [0035]    According to the Bluetooth standard, a radio transceiver device  2   1  is capable of identifying those devices with which it is capable of communicating with using an Inquiry procedure. This procedure causes the transceiver devices within range to transmit to the transceiver device their identities. Consequently, in this scenario, the memory  12   1  of the radio transceiver device  2   1  will contain the identities of all of the radio transceiver devices within range of the radio transceiver device  2   1 . However, it is still necessary for the radio transceiver device  2   1  to identify which one of the plurality of possible radio transceiver devices has been brought into a predetermined intimate physical relationship with it. Consequently when the identity of the second radio transceiver device  2   2  to which the radio transceiver device  2   1  is coupled is transferred to the processor  14   1  it may use this identity to select from the list of Bluetooth addresses stored in the memory  12   1  the Bluetooth address of the second radio transceiver device  2   2 . Therefore the radio transceiver device  2   1  is capable of communicating with a plurality of different radio transceiver devices  2   n  (n=2, 3, 4, 5 &amp; 6 in FIG. 1)but it chooses to communicate only with the device  2   2  with which it is in a predetermined intimate physical relationship.  
         [0036]    [0036]FIG. 8 illustrates an alternative way in which the first embodiment can be implemented. Instead of having the low power radio transceiver circuitry  10   1 , the processor  14   1 , the memory  12   1  and the sensor circuitry  16   1  within a body of the radio transceiver device  2   1 , the sensor circuitry  16   1  is located in an attachable/detachable cover. In the Figure, the radio transceiver device  2   1  which is of such a size that it can be held in a user&#39;s hand, comprises a body portion  80  and a replaceable cover portion  82  having a cavity  84  for receiving and retaining at least a portion of the body  80 . The cover  82  comprises sensor circuitry  16   1  and the body  80  comprises the low power radio transceiver circuitry  10   1 , the processor  14   1  and the memory  12   1 . An electrical connection is formed between an electrical contact  86   a  of the body  80  and an electrical contact  86   b  of the cover  82  when the cover  82  is attached to the body  80 . The electrical connection connects the sensor circuitry  16   1  to the processor  14   1 .  
         [0037]    Although the initiation of radio communication between two out of a plurality of radio communication devices has been described by bringing the devices into a predetermined physical relationship, embodiments of the invention extend to the initiation of radio communication between a multiplicity of radio communication devices by bringing the multiplicity of radio communication devices simultaneously or sequrntially into a predetermined physical realtionship.  
         [0038]    Although the present invention has been described in the preceding paragraphs with reference to various examples, it should be appreciated that modifications and variations to the examples given can be made without departing from the spirit or scope of the invention.