Abstract:
A portable radio telephone having an antenna which can be pivoted between a first position in which it projects from a surface of the telephone and a second position in which it projects from the surface of the telephone. The second position of the antenna relative to the surface of the telephone is different than the first position. The antenna is pivoted from the first position to the second position to control the operation of the telephone.

Description:
BACKGROUND OF THE INVENTION 
     The present invention relates to a portable radio telephone having a projecting antenna. The portable radio telephone may, for example, be a radio telephone such as a conventional handheld cellular telephone, or it may be a so-called smart radio telephone or personal organizer having radio frequency (RF) communication capabilities. 
     A handheld cellular telephone generally includes an antenna for transmitting and receiving radio frequency signals. Some handheld cellular telephones have antennas which are movable, for example, between retracted and extended positions. 
     European patent publication EP 0 516 490 shows an example of a movable antenna for a portable cellular radio telephone, in the form of a whip antenna which may be extended out of the housing of the portable telephone, or retracted into the housing of the portable telephone. 
     The Ericsson EH97 handheld cellular telephone shows another example of a movable antenna. Here the movable antenna is in the form of a rod antenna joined to the side of the cellular telephone housing so that it may rotate through 360 degrees. The antenna can be rotated manually by a user between a retracted position and an extended position (see FIG.  1 ). 
     SUMMARY OF THE INVENTION 
     According to the present invention there is provided a portable radio telephone having an antenna which can be pivoted between a first position in which it projects from a surface of the telephone housing, and a second position in which it projects from the surface of the telephone housing, to control the operation of the telephone. 
     A portable radio telephone in accordance with the invention may have an advantage that the telephone can be controlled simply by pivoting the antenna between a first position and a second position. 
     The antenna of the portable radio telephone projects from a surface of the telephone housing in both the first position and the second position. Thus a user can easily pivot the antenna from the first position to the second position or vice versa to control the operation of the telephone. This provides an advantage over conventional methods of controlling the operation of a telephone such as, for example, activating keys on a keypad or opening and closing a two-part telephone. 
     As the size of radio telephones decreases, the size of the keys of the keypad tends to decrease accordingly, whereas the size of the antenna tends to remain the same. Therefore, the use of a pivoting antenna in accordance with the invention may become increasingly advantageous as keys become smaller and more difficult to operate. In some instances the use of a pivoting antenna in accordance with the invention may make the use of a conventional keypad redundant. 
     Having the antenna projecting from the surface of the telephone housing in both the first position and the second position may also improve performance of the antenna by providing a better radiation pattern compared to an antenna not projecting from a surface. 
     Preferably the telephone comprises switching means for switching the telephone between first and second operational states in response to movement of the antenna between the first and second positions. In this way the telephone may operate in a first operational state when the antenna is in the first position and in a second operational state when the antenna is in the second position. The switching means may respond to movement of the antenna between the first and second positions by sensing the movement of the antenna as it pivots between the two positions. Alternatively, the switching means may respond to movement of the antenna between the first and second positions by sensing the antenna reaching the first and/or second positions. 
     In one preferred embodiment the first operational state of the telephone is an on-hook state and the second operational state of the telephone is an off-hook state. This may provide the advantage that a user may start and end a telephone call by simply moving the antenna back and forth between two predetermined positions. In this embodiment the portable telephone may dispose with the conventional ‘send’ and ‘end’ keys thus saving space on the keypad of the portable telephone. When carrying the portable telephone in a pocket this embodiment may provide a further advantage of allowing the user to answer calls quickly by pivoting the antenna as the telephone is removed from the pocket. 
     In another preferred embodiment the first operational state is a powered up state of the telephone and the second operational state is a powered down state of the telephone. 
     In another preferred embodiment the telephone includes a user actuable key, whereby in the first operational state the key is enabled and in the second operational state the key is disabled. This may provide an advantage that the user can avoid accidental depression of keys on the keypad by pivoting the antenna to a position in which the key is disabled. Ideally, this feature may also operate for more than one key of the keypad or ultimately all the keys of the keypad. In this way the pivotal movement of the antenna to a certain position may activate a so-called keyguard facility. 
     In another preferred embodiment the telephone further comprises a user interface including illuminating means, whereby in the first operational state the illuminating means is active and in the second operational state the illuminating means is inactive. This may provide an advantage that by pivoting the antenna the lights illuminating the display and/or keypad may be switched on or off. 
     In a preferred embodiment the portable radio telephone further comprises a user interface including voice recognition means, whereby in the first operational state the voice recognition means is active and in the second operational state the voice recognition means is inactive. 
     This may provide an advantageous way of making a telephone call whereby the antenna is pivoted to a position for activating the voice recognition, the user then speaks the name of the person to be called and the telephone dials the number. The call is then ended by moving the antenna back to its original position. 
     In a preferred embodiment the surface which the antenna projects from is an end surface of the telephone. Ideally the surface is a top surface of the telephone. 
     Preferably the antenna is a helical antenna which may be substantially axially symmetric. 
     The shape of the antenna may be cylindrical, or it may be conical. 
     In a preferred embodiment the antenna is attached to the telephone by a hinge arrangement. 
     In a preferred embodiment the hinge arrangement permits rotation of the antenna only in a single plane. 
     In a preferred embodiment the hinge permits rotation of the antenna only through an acute angle. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     Embodiments of the invention will now be described, by way of example, with reference to the accompanying drawings, in which: 
     FIG. 1 is a side and front view of the Ericsson EH97 cellular telephone discussed in the introduction; 
     FIG. 2 is a perspective view of a radio telephone in accordance with the invention with the antenna in a upright position; 
     FIG. 3 is a perspective view of the radio telephone of FIG. 2 with the antenna pivoted to an angled position. 
     FIG. 4 is a view of a radio telephone in accordance with the invention in use, with the antenna pivoted to an angled position; 
     FIG. 5 a  is a side view of a radio telephone in accordance with the invention with the antenna in a upright position; 
     FIG. 5 b  is a side view of the radio telephone of FIG. 4 a  with the antenna pivoted to an angled position. 
     FIG. 6 is a series of three partial views of a radio telephone in accordance with the invention, showing the antenna in three different pivoted positions. 
     FIG. 7 is another series of three partial views of a radio telephone in accordance with the invention, showing the antenna in three different pivoted positions. 
     FIG. 8 is another series of three partial views of a radio telephone in accordance with the invention, showing the antenna in three different pivoted positions. 
     FIG. 9 is another series of three partial views of a radio telephone in accordance with the invention, showing the antenna in three different pivoted positions. 
     FIG. 10 is a view of the radio telephone of FIG. 4 which shows pivoting of the antenna by a thumb of a user; 
     FIG. 11 is a side view of the radio telephone of FIG. 4 b  when placed on a surface; 
     FIG. 12 is cross-sectional view of a portion of a radio telephone in accordance with the invention, with the antenna in the upright position; 
     FIG. 13 is cross-sectional view of a portion of the radio telephone of FIG. 12, with the antenna pivoted to an angled position; 
     FIG. 14 is cross-sectional view of a portion of a radio telephone in accordance with the invention, with the antenna in the upright position; 
     FIG. 15 is cross-sectional view of a portion of the radio telephone of FIG. 14, with the antenna pivoted to an angled position; 
     FIG. 16 is an perspective view of a telephone in accordance with the invention; 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring to FIG. 2, there is shown a portable radio telephone  1  consisting of a main body portion  12  and an antenna  13 . 
     The main body portion  12  of the telephone comprises a generally rectangular housing having a front surface  16 , a back surface  17 , side surfaces  15 , a bottom surface  18 , and a top surface  14 . The main body portion is generally elongate and accordingly defines a major axis, shown as A—A in FIG.  2 . The telephone is designed to be brought into operating proximity with the head of a user as shown in FIG. 4 such that in general the front surface  16  faces the head of a user, the back surface  17  faces away from the head of the user, the bottom surface  18  faces downwards, and the top surface  14  faces upwards. 
     The main body portion  12  of the telephone  1  includes an earpiece  19  and a microphone  20  both situated on the front surface  16 . The earpiece  19  and microphone  20  are positioned to cooperate respectively with the ear and mouth of a user as shown in FIG.  4 . 
     The user interface of the telephone  1  further comprises a keypad including keys  21  for controlling the operation of the telephone, and a display  22  (e.g. an LCD display) for displaying information relevant to the operation of the telephone. Illuminating means (e.g. LED&#39;s) are provided to help a user see the keypad and display in bad light conditions. These illuminating means may be switched on or off depending on the operational state of the telephone. 
     The antenna  13  of the telephone  1  projects from the top surface  14  such that it extends beyond the housing of the main body portion  12 . The antenna  13  is a helical antenna having a generally cylindrical shape with a rounded distal end. The antenna  13  defines a major axis about which the antenna is axially symmetric. The shape of the antenna may take other similarly symmetric forms such as a conical shape. These forms of antenna are often referred to as stub antennas. In FIG. 2 the major axis of the antenna is substantially parallel with the major axis of the main body portion and is normal and perpendicular to the top surface. 
     Referring to FIG. 5 a  there is shown a side view of another telephone sharing the same features as the telephone in FIG.  2 . The antenna  13  again projects from the top surface  14  such that it extends beyond the housing of the main body portion  12 . In this embodiment the top surface is curved or rounded. As shown in FIG. 4 a , the major axis of the antenna is substantially parallel with the major axis of the main body portion and is again normal to the top surface. 
     In accordance with the invention the antenna  13  of the telephone may be pivoted from the upright position shown in FIGS. 2 and 5 a , to an angled or canted position as shown in FIGS. 3 and 5 b.    
     As shown in FIGS. 2 and 3 the antenna  13  may pivot about an axis B—B such that the major axis of the antenna is substantially perpendicular to axis B—B throughout the rotation of the antenna. Accordingly, the antenna rotates only in a single plane. This single plane is parallel with the side surfaces, perpendicular to the top surface, and perpendicular to the front surface. 
     The pivotal rotation of the antenna is limited such that the antenna may only rotate through a small angle φ between the upright position and the angled position as indicated by arrow C in FIGS. 3 and 5 b . In this way the antenna always projects from the top surface of the telephone. 
     When the antenna is in the canted position the angle subtended by the major axis of the main body portion and the major axis of the antenna equals φ. In the canted position the antenna is also directed or orientated away from front surface  16  as shown in FIGS. 3,  4 , and  5   b.    
     When the antenna is in the upright position and the telephone is brought into operating proximity with the head of a user, the radio frequency performance of the antenna is affected. This is due to the head of the user disturbing the radiation pattern normally produced by the antenna. By pivoting the antenna to the canted position while the telephone is in operating proximity with the head of a user, the antenna performance is improved. This is due to the antenna pivoting away from the head so that the head has less of a disturbing effect on the radiation pattern produced by the antenna. 
     Referring to FIGS. 6 to  9  there are shown four possible ways in which an antenna of a telephone in accordance with the present invention may be biased and/or locked as it pivots between the upright and canted positions. In each of the FIGS. 6 to  9  there are shown  3  views, namely a view of the antenna in the upright position, a view of the antenna in the partially canted position, and a view of the antenna in the fully canted position. Each arrow in the FIGS. 5 to  8  refers to the direction in which the antenna is biased. The biasing may be provided by, for example, a spring action. 
     Referring specifically to FIG. 6, the antenna is neutrally biased in the partially canted position, and on either side of this position is biased towards the upright and fully canted positions. Accordingly, the antenna is stable in the upright and the fully canted positions. 
     Referring specifically to FIG. 7, the antenna is releasably locked in the upright position, and once released is biased towards the fully canted position. Accordingly, the antenna is stable in the upright and the fully canted positions. 
     Referring specifically to FIG. 8, the antenna is releasably locked in the fully canted position, and once released is biased towards the upright position. Accordingly, the antenna is stable in the upright and the fully canted positions. 
     Referring specifically to FIG. 9, the antenna is always biased towards the fully canted position. Accordingly, the antenna is stable in the fully canted position. 
     Referring now to FIG. 10, there is shown the telephone of FIGS. 5 a  and  5   b  being operated by a hand of a user. With the fingers and palm of the hand gripping the main body portion  12 , the thumb is free to pivot the antenna  13  from the upright position to the canted position. Thus the telephone allows one handed pivoting of the antenna to control the operation of the telephone. It is also possible to pivot the antenna with two hands. 
     When storing the telephone of FIG. 4 a  in a pocket, for example, it is desirable to have the antenna of the telephone in the upright position so that the profile of the telephone is minimised. Another instance when it is appropriate to have the antenna in the upright position is when placing the telephone on a flat surface. Sometimes, however, the antenna may be in the canted position when it is placed on a flat surface as shown in FIG.  11 . In this situation the telephone is likely to experience a downward force on its front surface  16 , as indicated by the arrow labelled F. An advantage of the telephone in this situation is that the antenna may adopt the upright position as a consequence of the force F pivoting the antenna relative to the main body portion. Accordingly, the telephone is likely to wobble on the surface and also the antenna is less liable to break or snap as a result of the force F. 
     FIGS. 12 and 13 are cross-sectional views of the telephone shown in FIGS. 2 and 3, showing a pivot arrangement for the antenna, and a switch responsive to pivotal movement of the antenna between the upright position and the canted position. The antenna  13  pivots about the pivot pin  25  only between the upright position shown in FIG.  12  and the angled position shown in FIG.  13 . The pivotal rotation of the antenna is limited in this way by the stop pins  27  which abut the antenna to prevent further pivotal rotation at the extremes of the antenna&#39;s rotation. A switch  26  is provided in the housing of the main body portion  12  and is coupled to a microprocessor of the telephone to control the operation thereof. The switch  26  is actuated depending on whether a switch actuator  29  on the antenna  13  is in close proximity with the switch. In FIG. 12 the antenna is in the upright position and the switch actuator  29  is not in close proximity with the switch, therefore the switch is not actuated. However, when the antenna is pivoted to the angled position as in FIG. 13, the switch actuator  29  is in close proximity with the switch and the switch is actuated. The switch  26  may be a magnetic reed switch and the switch actuator  29  a magnet. 
     FIGS. 14 and 15 are cross-sectional views of the telephone shown in FIGS. 2 and 3, showing an alternative pivot arrangement for the antenna, and an alternative switch responsive to pivotal movement of the antenna between the upright position and the canted position. The antenna pivots in the same way as in FIGS. 12 and 13. However, the antenna  13  in this embodiment includes a camming surface  30  which abuts a sprung cam follower  28  in such a way as to produce the biasing action shown in FIG.  6 . The switch  26  is actuated in this embodiment as a result of a surface of the antenna  13  urging the switch closed. In FIG. 14 the antenna is in the upright position and a surface of the antenna pushes the switch closed, therefore the switch is actuated. However, when the antenna is pivoted to the angled position, the surface of the antenna does not urge the switch closed and the switch is not actuated. The switch may be a leaf switch. 
     Another embodiment in accordance with the invention is shown in FIG.  16 . In this embodiment the main body portion  12  is pen shaped and the antenna  13  extends beyond the housing of the main body portion. The main body portion also has a microphone  20  situated towards the bottom of the telephone and a loudspeaker  19  situated towards the top of the telephone. 
     In view of the foregoing description it will be evident to a person skilled in the art that various modifications may be made within the scope of the invention. 
     The scope of the present disclosure includes any novel feature or combination of features disclosed therein either explicitly or implicitly or any generalisation thereof irrespective of whether or not it relates to the claimed invention or mitigates any or all of the problems addressed by the present invention. The applicant hereby gives notice that new claims may be formulated to such features during prosecution of this application or of any such further application derived therefrom.