Antenna control system

Information

  • Patent Grant
  • 6567051
  • Patent Number
    6,567,051
  • Date Filed
    Monday, February 11, 2002
    22 years ago
  • Date Issued
    Tuesday, May 20, 2003
    21 years ago
Abstract
An antenna control system enabling the remote variation of antenna beam tilt. A drive means continuously adjusts phase shifters of a feed distribution network to radiating elements to continuously vary antenna beam tilt. A controller enables the beam tilt of a number of antenna at a site to be remotely varied.
Description




THE TECHNICAL FIELD




The present invention relates to an antenna control system for varying the beam tilt of one or more antenna. More particularly, although not exclusively, the present invention relates to a drive system for use in an antenna which incorporates one or more phase shifter.




BACKGROUND OF THE INVENTION




In order to produce downtilt in the beam produced by an antenna array (for example a panel antenna) it is possible to either mechanically tilt the panel antenna or electrically steer the beam radiated from the panel antenna according to techniques known in the art.




Panel antennas, such as those to which the present application is concerned, are often located on the sides of buildings or similar structures. Mechanical tilting of the antenna away from the side of the building increases the susceptibility of the installation to wind induced vibration and can impact on the visual environment in situations where significant amounts of downtilt are required.




In order to avoid the above difficulties, electrical beam steering can be effected by introducing phase delays into the signal input into radiating elements or groups of radiating elements in an antenna array. Such techniques are described in New Zealand Patent Specification No. 235010.




Various phase delay techniques are known, including inserting variable length delay lines into the network feeding to the radiating element or elements, or using PIN diodes to vary the phase of a signal transmitted through the feeder network.




A further means for varying the phase of two signals is described in PCT/NZ94/00107 whose disclosure is incorporated herein by reference. This specification describes a mechanically operated variable differential phase shifter incorporating one input and two outputs.




For the present purposes it is sufficient to note that phase shifters such as those described in PCT/NZ94/00107 are adjusted mechanically by sliding an external sleeve along the body of the phase shifter which alters the relative phase of the signals at the phase shifter outputs.




A typical panel antenna will incorporate one or more phase shifters and the present particular embodiment includes three phase shifters. A signal is input to the primary phase shifter which splits the signal into two signals having a desired phase relationship. Each phase shifted signal is then input into a secondary phase shifter whose outputs feeds at least one radiating element. In this manner a progressive phase shift can be achieved across the entire radiating element array, thus providing a means for electrically adjusting the downtilt of the radiated beam. Other phase distributions are possible depending on the application and shape of the radiated beam.




While the steering action is discussed in the context of downtilt of the radiated beam, it is to be understood that the present detailed description is not limited to such a direction. Beam tilt may be produced in any desired direction.




Another particular feature of the variable differential phase shifters is that they provide a continuous phase adjustment, in contrast with the more conventional stepped phase adjustments normally found in PIN diode or stepped length delay line phase shifters.




In a panel antenna of the type presently under consideration, it is desirable to adjust the entire phase shifter array simultaneously so that a desired degree of beam tilt may be set by the adjustment of a single mechanical setting means. The mechanical drive which performs such an adjustment must result in reproducible downtilt angles and be able to be adapted to provide for a number of different phase shifter array configurations.




It is also desirable that the beam tilt of an antenna may be varied remotely to avoid the need for personnel to climb a structure to adjust antenna beam tilt.




DISCLOSURE OF THE INVENTION




It is an object of the present invention to provide a mechanical drive system for use in adjusting mechanical phase shifters which mitigates the abovementioned difficulties, provides a solution to the design requirements of the antennas or antenna arrays described above, or at least provides the public with a useful choice.




Accordingly, there is provided a mechanical adjustment means for adjusting the relative phase shifts produced by a plurality of phase shifters connected to an array of radiating elements, said mechanical adjustment means including:




first means for moving a first portion of a first phase shifter relative to a second portion of said first phase shifter to vary the phase difference between output signals from the first phase shifter; and




second means for moving a first portion of a second phase shifter relative to a second portion of said second phase shifter to vary the phase difference between output signals from the second phase shifter, wherein the second phase shifter is fed from an output of the first phase shifter and the degree of movement of the second means is dependent upon the degree of movement of the first means.




Preferably, movement of the second means results in simultaneous movement of a first portion of a third phase shifter with respect to a second portion of the third phase shifter wherein the third phase shifter is fed from an output of the first phase shifter.




Preferably the outputs of the second and third phase shifters are connected to radiating elements so as to produce a beam which tilts as the first and second means adjusts the phase shifters.




Preferably the movement of the first portion of the first phase shifter a first distance relative to the second portion of the first phase shifter results in relative movement between first portions of the second and third phase shifters relative to second portions of the second and third phase shifters of about twice the first distance.




According to a first preferred embodiment the first means includes a gear wheel which drives a rack connected to a first portion of the first phase shifter, arranged so that rotation of the first gear wheel causes the first portion of the first phase shifter to move relative to the second portion of the first phase shifter. Preferably, the second portion of the first phase shifter is mounted to a carriage and the outputs of the first phase shifter are connected to inputs of the second and third phase shifters by push rods so that movement of the second portion of the first phase shifter moves the first portions of the second and third phase shifters with respect to the second portions of the second and third phase shifters.




Preferably a second gear is provided co-axial with and connected to a shaft driving the first gear which drives a rack connected to the second part of the first phase shifter so that rotation of the second gear causes movement of the first portion of the second and third phase shifters relative to the second portions of the second and third phase shifters.




Preferably the ratio between the first and second gear wheels is about 3:1.




According to a second embodiment of the present invention the adjustment means includes a shaft and said first means includes a first threaded portion provided on said shaft and a first cooperating threaded member connected to the first portion of the first phase shifter. The second means includes a second threaded portion provided on said shaft and a second cooperating threaded member connected to the first portion of the second phase shifter. The arrangement is such that rotation of the shaft causes the first portion of the first phase shifter to move relative to the second portion of the first phase shifter at a rate of about twice that of the movement of the first portion of the second phase shifter relative to the second portion of the second phase shifter.




Preferably the second threaded member is connected to the second portion of the first phase shifter and moves the first portion of the second phase shifter via a push rod. This push rod is preferably a coaxial line connecting an output from the first phase shifter to the input to the second phase shifter.,




Preferably there is further provided a third phase shifter fed from a second output of the first phase shifter via a push rod which moves a first portion of the third phase shifter in unison with the first portion of the second phase shifter.




According to a further aspect of the invention there is provided an antenna system comprising one or more antenna including electromechanical means for varying the downtilt of the antenna and a controller, external to the antenna, for supplying drive signals to the electromechanical means for adjusting downtilt.




Preferably the system includes a plurality of antennas and the controller may adjust the downtilt for the plurality of antennas and store the degree of downtilt of each antenna in memory.




Preferably the controller may be controlled remotely from a control centre so that a plurality of such systems may be remotely controlled as part of a control strategy for a number of cellular base stations.




Preferably the electromechanical means varies the electrical downtilt of each antenna and means are included for monitoring the electromechanical means and providing signals representative of the position of the electromechanical means to the controller.











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


: shows a panel antenna incorporating a phase shifter drive mechanism according to a first embodiment of the invention.




FIG.


2


: illustrates a primary phase shifter incorporating a gear rack.




FIG.


3


: illustrates an exploded view of the adjustment assembly incorporated into the carriage.




FIG.


4


: shows diagrammatically the operation of the drive mechanism according to the first embodiment.




FIG.


5


: shows a panel antenna incorporating a phase shifter drive mechanism according to a second embodiment of the invention.




FIG.


6


: shows the phase shifter drive mechanism of

FIG. 5

in detail.




FIG.


7


: shows the electrical connection of the motor, switches and reed switch of the drive mechanism shown in FIG.


6


.




FIG.


8


: shows a controller for controlling the drive mechanism shown in

FIGS. 6 and 7

.





FIG. 9

shows an antenna system according to one aspect of the present invention having a plurality of antennas controlled by a controller.











BEST MODE FOR CARRYING OUT THE INVENTION




Referring to

FIG. 1

there is shown the back side of a panel antenna


4


having a first phase shifter


1


, a second phase shifter


2


, a third phase shifter


3


and a phase shifter drive mechanism


5


. Feed line


6


is connected to input


7


of phase shifter


1


. A first portion


8


of phase shifter


1


is moveable relative to a second portion


9


of phase shifter


1


.




Output signals from phase shifter


1


are supplied via lines


10


and


11


to inputs


12


and


13


of phase shifters


2


and


3


respectively. Feed lines


10


and


11


comprise coaxial push rods which serve the functions both of feeding signals from the outputs of phase shifter


1


to phase shifters


2


and


3


and moving first portions


14


and


15


of phase shifters


2


and


3


relative to second portion


16


and


17


of phase shifters


2


and


3


respectively.




Signals output from phase shifters


2


and


3


are supplied via coaxial lines


18


,


19


,


20


and


21


to be fed to respective radiating elements (not shown).




In use first portion


8


of phase shifter


1


may be moved relative to second portion


9


of phase shifter


1


to change the relative phase of signals supplied via lines


10


and


11


to phase shifters


2


and


3


respectively. First portions


14


and


15


of phase shifters


2


and


3


may be moved relative to second portions


16


and


17


of phase shifters


2


and


3


to vary the phase of signals supplied by lines


18


,


19


,


20


and


21


to respective radiating elements.




When phase shifters


1


,


2


and


3


are adjusted in the correct respective portions the beam emitted by the antenna can be tilted as required. It will be appreciated that where a less defined beam is required fewer phase shifters may be employed.




To achieve even continuous beam tilting for the embodiment shown in

FIG. 1

the first portions


14


and


15


of phase shifters


2


and


3


should move relative to the second portion


16


and


17


of phase shifters


2


and


3


at the same rate. The first portion


8


of phase shifter


1


must however move relative to the second portion


9


of phase shifter


1


at twice this rate. In the arrangement shown second portion


9


of phase shifter


1


is connected to carriage


22


. Movement of carriage


22


results in movement of first portions


14


and


15


of phase shifters


2


and


3


via push rods


10


and


11


.




Referring now to

FIG. 4

, operation of the phase shifter drive mechanism will be explained. Second portion


9


of phase shifter


1


is mounted to a carriage


22


which can move left and right. If carriage


22


is moved to the left first portions


14


and


15


of phase shifters


2


and


3


will be moved to the left via push rods


10


and


11


. First portion


8


of phase shifter


1


may be moved relative to second portion


9


of phase shifter


1


to vary the phase of signal supplied to phase shifters


2


and


3


.




According to this first embodiment a rack


23


is secured to first portion


8


of phase shifter


1


. Upon rotation of gear wheel


24


first portion


8


of phase shifter


1


may be moved to the left or the right. A smaller gear wheel


25


is secured to and rotates with gear wheel


24


. This gear wheel engages with a rack


26


provided on carriage


22


. A further gear wheel


27


is provided which may be driven to rotate gear wheels


24


and


25


simultaneously.




Gear wheel


24


has 90 teeth whereas gear wheel


25


has 30 teeth. It will therefore be appreciated that rotation of gear wheel


24


results in first portion


8


of phase shifter


1


being moved three times as far as carriage


22


(and hence first portions


14


and


15


of phase shifters


2


and


3


). However, as carriage


22


is moving in the same direction as the first portion


8


of phase shifter


1


it will be appreciated that the relative movement between first portion


8


and second portion


9


of phase shifter


1


is twice that of the relative movement between the first and second portions of phase shifters


2


and


3


. Accordingly, this arrangement results in the relative phase shift produced by phase shifter


1


being twice that produced by phase shifters


2


and


3


(as required to produce even beam tilting in a branched feed arrangement).




The particular arrangement is shown in more detail in

FIGS. 2

to


4


. It will be appreciated that gear wheel


27


may be driven by any appropriate manual or driven means. Gear wheel


27


may be adjusted by a knob, lever, stepper motor or other driven actuator. A keeper


28


may be secured in place to prevent movement once the desired settings of the phase shifters have been achieved.




Referring now to

FIGS. 5 and 6

, a second embodiment will be described. As seen in

FIG. 5

, the arrangement is substantially the same as that shown in the first embodiment except for the drive mechanism


30


employed, which is shown in FIG.


6


.




In this embodiment the drive mechanism includes a shaft


31


having a first threaded portion


32


and a second threaded portion


33


provided thereon. A first threaded member


34


is connected to a first portion


35


of primary phase shifter


36


. A second threaded member


37


is connected to the second portion


38


of primary phase shifter


36


.




First threaded portion


32


is of three times the pitch of second threaded portion


33


(e.g. the pitch of the first threaded portion


32


is 6 mm whereas the pitch of the second threaded portion is 2 mm). In this way, first portion


35


is driven in the direction of movement at three times that of second portion


38


. In this way the phase shift produced by primary phase shifter


36


is twice that of second and third phase shifters


39


and


40


.




Shaft


31


is rotated by motor


41


. This may suitably be a geared down 12 volt DC motor. The other end of shaft


31


is supported by end bearing


42


. A reed switch


43


is provided to detect when magnets


44


pass thereby. In this way the number of rotations of shaft


31


may be monitored. Limit switches


45


and


46


may be provided so that the motor is prevented from further driving shaft


31


in a given direction if threaded member


34


abuts a lever of limit switch


45


or


46


respectively.




Operation of the drive means according to the second embodiment will now be described by way of example. Motor


41


may rotate shaft


31


in an anticlockwise direction, viewed from right to left along shaft


31


. Threaded member


37


is driven by second threaded portion


33


to move push rods


47


and


48


to the left, and thus to adjust phase shifters


39


and


40


.




Threaded member


34


is driven to the left at three times the rate of threaded member


37


. First portion


35


thus moves to the left at three times the rate of second portion


38


. First portion


35


therefore moves relative to second portion


38


at twice the speed the first portions of phase shifters


39


and


40


move relative to their respective second portions. In this way, delays are introduced in the paths to respective radiating elements so as to produce an evenly tilting beam.




The conductivity of reed switch


43


is monitored so that the number of rotations, or part rotations, of shaft


31


may be monitored. If the motor continues driving shaft


31


until threaded member


34


abuts the lever of limit switch


45


then logic circuitry will only permit motor


41


to drive in the opposite direction. Likewise if threaded member


34


abuts the lever of limit switch


46


the motor


41


will only be permitted to drive in the opposite direction.




It will be appreciated that the techniques of both embodiments could be employed in antenna arrays using a larger number of phase shifters. In such applications the relative movement of the first portion of each phase shifter relative to the second portion of each phase shifter would decreased by a factor of 2 for each successive phase shifter along each branch. The ratios used may be varied if the radiation pattern of the antenna needs to be altered to account for the directivity of the individual radiating elements and the effect of the back panel as the amount of downtilt is varied.




Components of the drive mechanism


30


are preferably formed of plastics, where possible, to reduce intermodulation. Threaded members


34


and


37


preferably include plastic links to phase shifter


36


to reduce intermodulation.




It will be appreciated that a number of mechanical drive arrangements may be used to achieve adjustment of the phase shifters in the desired ratio. It is also to be appreciated that sophisticated control electronics may be employed, although the simplicity of construction of the present invention is seen as an advantage.





FIG. 7

shows how motor


41


, reed switch


43


and switches


45


and


46


are connected to lines


71


,


72


,


76


and


77


from an external controller. Lines


71


,


72


,


76


and


77


are sheathed by conduit


78


. Lines


71


and


72


supply current to drive motor


41


. Section


73


ensures that if threaded member


34


is driven to either the left-hand side limit or the right-hand side limit it can only be driven in the opposite direction. In the position shown in

FIG. 7

, switch


45


directly connects line


71


to switch


46


via diode


74


. In the position shown switch


46


connects line


71


to motor


41


via diode


75


. This is the normal position of the switches when threaded member


34


is not at either extreme limit. When threaded member


34


is driven to the extreme left, for example, and actuates switch


45


, then switch


45


open circuits the path via diode


74


. Diode


74


allows current flow in the direction allowing motor


41


to drive to the left. Accordingly, when switch


45


is open, motor


41


can only drive in such a direction as to drive threaded member


34


to the right (i.e.: current in the direction allowed by diode


75


).




Likewise, if threaded member


34


is driven to the extreme right, switch


46


is opened to break the path via diode


75


. This prevents motor


41


driving in such a direction as to drive threaded member


34


further to the right.




Lines


76


and


77


are connected to reed switch


43


so that the opening and closing of reed switch


43


may be monitored by an external control unit. In use, the opening and closing of reed switch


43


may be monitored to determine the position of threaded member


34


, and hence the corresponding degree of tilt of the antenna.




To select an initial angle of downtilt threaded member


34


may be driven to the extreme right. An external controller may provide a current in one direction to motor


41


to drive member


34


to the right. The motor will continue to be driven to the right until threaded portion


34


abuts switch


46


. When switch


46


is opened diode


75


will be open circuited, which will prevent the motor being driven further to the right.




The controller will sense that threaded member


34


is at its extreme right position as it will detect that reed switch


43


is not opening and closing. After a predetermined delay the controller may then provide a current in the opposite direction via lines


71


and


72


to motor


41


to drive it to the left. As the motor is driven to the left the controller will monitor the opening and closing of reed switch


43


to determine how far threaded member


34


has moved to the left. The controller will continue to move threaded member


34


to the left until reed switch


43


has opened and closed a predetermined number of times, corresponding to a desired angle of downtilt. Alternatively, threaded member


34


may be driven to the extreme left and then back to the right.




As shown in

FIG. 9

, at an antenna site a number of such panels


90


may be installed and controlled by a single controller


80


as shown in FIG.


8


. The four wires


71


,


72


,


76


, and


77


correspond to respective cable groups


78


to three such antenna panels. Controller


80


may be provided at the base of an antenna site to allow an operator to adjust the tilt of a plurality of antennas at ground level, rather than requiring a serviceman to climb up the antenna structure


92


and adjust each antenna manually. Alternatively, controller


80


may be a hand-held unit which can be plugged into a connector at the base of an antenna to adjust the antenna at a site.




Controller


80


may include a display


81


, an “escape” button


82


, an “enter” button


83


, an “up” button


84


and “down” button


85


. At power up display


81


may simply display a home menu such as “Deltec NZ Ltd© 1995”. Upon pressing any key, a base menu may be displayed including options such as:




unlock controls




set array tilt




measure tilt




enable array




disable array




lock controls




The up/down keys may be used to move through the menu and the enter key


83


used to select an option. If “unlock controls” is selected a user will then be required to enter a three digit code. The up/down keys may be used to move through the numbers


0


to


9


and enter used to select each number. If the correct code is entered “locked released” appears. If the incorrect code is entered “controls locked” appears and a user is returned to the home menu. If “set array tilt” is selected from the base menu the following may appear:




set array tilt




array:


01


X.X°




The up-down keys


84


,


85


may be used to select the desired array number. The enter key accepts the selected array and the previously recorded angle of downtilt may be displayed as follows:




set array tilt




array:


01


4.6°




In this example the previously set angle of downtilt with 4.6°. Using the up/down keys


84


,


85


a new angle may be entered. Controller


80


may then provide a current to motor


41


via lines


71


and


72


to drive threaded portion


34


in the desired direction to alter the downtilt. The opening and closing of reed switch


43


is monitored so that threaded member


34


is moved in the desired direction for a predetermined number of pulses from reed switch


43


. The downtilt for any other array may be changed in the same manner. If the controller is locked a user may view an angle of downtilt but will not be able to alter the angle.




If the “measure array” option is selected the present angle of downtilt of the antenna may be determined. Upon selecting the “measure tilt” function from the base menu, the following display appears:




measure tilt




array:


01


X.X°




The up/down buttons may be used to select the desired array. The enter key will accept the selected array. To measure the actual angle of downtilt controller


80


drives a motor


41


of an array to drive member


34


to the right. Motor


41


is driven until threaded member


34


abuts switch


46


. The controller


80


counts the number of pulses from reed switch


43


to determine how far threaded portion


34


has traveled. At the extreme right position the controller


80


determines and displays the angle of downtilt, calculated in accordance with the number of pulses connected from reed switch


43


. The controller


80


then drives threaded member


34


back in the opposite direction for the same number of pulses from reed switch


43


so that it returns to the same position. The angle of downtilt for each antenna may be stored in memory of controller


80


. This value will be updated whenever the actual angle of downtilt is measured in this way. The “measure tilt” function may not be used if the controller is locked.




Controller


80


may include tables in memory containing the number of pulses from reed switch


43


that must be counted for threaded member


34


to achieve each desired degree of downtilt. This may be stored as a table containing the number of pulses for each required degree of downtilt, which may be in 0.1° steps. This approach ensures that any non-linearities of the antenna may be compensated for as the tables will give the actual amount of movement required to achieve a desired downtilt for a given antenna.




The “enable array” function may be used to enable each array when installed. The controller


80


will be prevented from moving any array that has not been enabled. Controller


80


will record in memory which arrays have been enabled. The “disable array” function may be used to disable arrays in a similar manner.




The “lock controls” function may be used to lock the controller once adjustment has been made. A “rack error” signal may be displayed if the array has not operated correctly. This will indicate that an operator should inspect the array.




Adjustment of the array may also be performed remotely. Controller


80


may be connected to modem


86


via serial line


87


which may connect via telephone line


88


to a central controller


89


. Alternatively, the controller


80


may be connected to a central controller


89


via a radio link etc. The functions previously discussed may be effected remotely at central controller


89


. In a computer controlled system adjustments may be made by a computer without operator intervention. In this way, the system can be integrated as part of a control strategy for a cellular base station. For example, a remote control centre


89


may adjust the downtilt of antennas at a cellular base station remotely to adjust the size of the cell in response to traffic demand. It will be appreciated that the capability to continuously and remotely control the electrical downtilt of a number of antenna of a cellular base station may be utilised in a number of control strategies.




Central controller


89


may be a computer, such as an IBM compatible PC running a windows based software program. A main screen of the program may show information regarding the antenna under control as follows:























TYPE




CURRENT









NAME




ANGLE




VALUE




NEW




STATUS





























GROUP 1











antenna 1




1 south




VT01




12°




12.5°




setting






antenna 2




1 north




VT01




12°




12.5°




queued






antenna 3




1 west




VTO1




12°




12.5°




queued






GROUP 2






antenna 4




2 south




VT01




 6°





pending






antenna 5




2 north




VT01




 6°




 .5°




nudging






antenna 6




2 west




VTO1




 6°





faulty














The antennas may be arranged in groups at each site. Group 1 for example contains antennas


1


,


2


and


3


. The following information about each antenna is given:




Name: this is the user assigned name such as


1


south,


1


north,


1


west etc.




Type: this is the antenna type which the controller communicates to the PC at start-up.




Current Angle: this is the actual degree of beam tilt of an antenna which is communicated from the controller to the PC at start-up. The controller also supplies to the PC each antennas minimum and maximum angles of tilt.




New Value: by moving a pointer to the row of an antenna and clicking a button of a mouse the settings of an antenna may be varied. When a user clicks on the mouse the following options may be selected:




Name—the user may change the group or antenna name.




Adjust—a user may enter a new angle in the “new value” column to set the antenna to a new value.




Nudge—the user may enter a relative value (i.e.: increase or decrease the tilt of an antenna by a predetermined amount).




Measure—the controller may be instructed to measure the actual angle of tilt of an antenna or group of antennas.




If an antenna is in a “fault” condition then it may not be adjusted and if a user clicks on a mouse when that antenna is highlighted a dialogue box will appear instructing the user to clear the fault before adjusting the antenna.




Each antenna also includes a field indicating the status of the antenna as follows:




O.K.—the antenna is functioning normally.




Queued—an instruction to read, measure, set or nudge the antenna has been queued until the controller is ready.




Reading—when information about an antenna is being read from the controller.




Measuring—when the actual degree of tilt of the antenna is being measured.




Setting—when a new tilt angle is being set.




Nudging—when the tilt angle of the antenna is being nudged.




Faulty—where an antenna is faulty.




When adjusting, measuring or nudging an antenna a further dialogue box may appear describing the action that has been instructed and asking a user to confirm that the action should be taken. This safeguards against undesired commands being carried out.




Information for a site may be stored in a file which can be recalled when the antenna is to be monitored or adjusted again. It will be appreciated that the software may be modified for any required control application.




Controller


80


may be a fixed controller installed in the base of an antenna site or could be a portable control unit which is plugged into connectors from control lines


78


.




Where in the foregoing description reference has been made to integers or components having known equivalents then such equivalents are herein incorporated as if individually set forth.




Although this invention has been described by way of example it is to be appreciated that improvements and/or modifications may be made thereto without departing from the scope or spirit of the present invention.




INDUSTRIAL APPLICABILITY




The present invention may find particular application in antenna systems, such as those used in cellular communication systems.



Claims
  • 1. A method of adjusting a fixed beam elevation in a cellular base station telecommunication system, the system having a panel antenna adapted to mount a plurality of vertically spaced radiating elements, the method comprising:providing a differential electromechanical phase shifter having a transmission line section coupled to said radiating elements, and a transmission line input which is moveable relative to said transmission line section to differentially adjust physical path lengths of transmission line outputs to said coupled radiating elements; operatively linking a first controller to said electromechanical phase shifter; operatively coupling a second controller to said first controller from a location remote from said first controller; and employing said first and second controllers and from the location of said second controller effecting controlled movement of said transmission line input relative to said transmission line section to adjust the beam from a first fixed elevation to a second fixed elevation.
  • 2. The method defined by claim 1 wherein said controlled movement is produced by an electric motor located at the antenna which is mechanically coupled to said phase shifter and electrically coupled directly to said first controller.
  • 3. The method of claim 2 wherein said controlled movement is effected by motor-driven drive devices selected from the group consisting of a screw drive, rack-and-pinion drive, and gear drive.
  • 4. The method of claim 2 wherein said motor is a pulse driven motor, and wherein said method includes:causing the motor to displace said transmission line input to a displacement limit position corresponding to a predetermined signal phasing; and providing a predetermined number of pulses to the motor to cause the motor to displace said transmission line input away from said displacement limit position by a predetermined amount so as to achieve a predetermined beam elevation.
  • 5. The method of claim 1 wherein the phase shifter has plastic components to reduce intermodulation distortion.
  • 6. The method of claim 1 wherein said phase shifter is adapted to adjust beam elevation selected in response to traffic demands.
  • 7. The method of claim 1 wherein at least one of said operatively linking and operatively coupling steps uses a wireless link.
  • 8. The method of claim 7 further including the step of configuring said wireless link as a radio link.
  • 9. The method of claim 1 further including the step of locking said phase shifter after it has been adjusted.
  • 10. The method of claim 1 wherein said first and second controllers control said phase shifter through a telephone link.
  • 11. The method of claim 1 wherein at least one of said controllers is personal computer.
  • 12. The method of claim 1 further including the step of locating said first controller at an antenna support structure, and remotely locating said second controller from said first controller.
  • 13. The method of claim 1 further including the step of locating said first and second controllers remotely from said antenna.
  • 14. The method of claim 1 further including the step of adjusting said phase shifter to produce an increase in an elevation angle of the beam or a decrease in an elevation angle of the beam, said adjusting performed by at least one of said first and second controllers.
  • 15. The method of claim 1 including the step of adjusting said phase shifter to produce selected different phasing of signals supplied to at least selected radiating elements, said adjusting performed by at least one of said first and second controllers.
  • 16. The method of claim 1 including the step of adjusting a phasing of signals supplied to at least selected radiating elements by predetermined amounts, said adjusting performed by at least one of said first and second controllers.
  • 17. The method of claim 1 including the step of measuring a phase value of signals supplied to at least selected radiating elements, said measuring performed by at least one of said first and second controllers.
  • 18. A cellular base station telecommunication system, comprising:a panel antenna adapted to mount a plurality of spaced radiating elements producing a beam having a fixed elevation; a differential electromechanical phase shifter having a transmission line section coupled to said radiating elements and a transmission line input which is moveable relative to said transmission line section to differentially adjust physical path lengths of transmission line outputs to the coupled radiating elements; an electric motor mechanically coupled to said phase shifter; a first controller operatively linked to said electromechanical phase shifter; and a second controller operatively linked to said first controller, said first and second controllers being configured to effect displacement of said transmission line input relative to said transmission line section to adjust the beam from a first fixed elevation to a second fixed elevation.
  • 19. The system of claim 18 configured to adjust selected beam elevation in response to traffic demands.
  • 20. The system of claim 18 wherein said controlled movement is effected by drive devices selected from the group consisting of a screw drive, rack-and-pinion drive, and gear drive.
  • 21. The system of claim 18 wherein at least one of said links is a telephone link.
  • 22. The system of claim 18 wherein at least one of said links is a wireless link.
  • 23. The system of claim 22 wherein said wireless link is a radio link.
  • 24. The system of claim 18 further including a phase shifter lock.
  • 25. The system of claim 18 wherein at least one of said controllers is a personal computer.
  • 26. The system of claim 18 further including an antenna support structure wherein said first controller is located at said antenna support structure.
  • 27. The system of claim 18 further including an antenna support structure wherein at least one of said first and second controllers is located remotely from said antenna support structure.
  • 28. The system of claim 18 adapted to adjust a phasing of signals supplied to the radiating elements so as to cause an increase in an elevation angle of the beam or a decrease in an elevation angle of the beam.
  • 29. The system of claim 18 adapted to select a predetermined phasing of signals supplied to at least selected radiating elements.
  • 30. The system of claim 18 adapted to change a phase of the signals supplied to at least selected radiating elements by predetermined amounts.
  • 31. The system of claim 18 adapted to measure a phase value of signals supplied to at least selected radiating elements.
  • 32. The system of claim 18 adapted to identify a status of said antenna.
  • 33. The system of claim 18 wherein at least one of said controllers is a portable or handheld device.
  • 34. The system of claim 18 further including an antenna support structure, and wherein said first controller is located at said support structure and said second controller is remotely located from said support structure.
  • 35. The system of claim 34 wherein said first and second controllers are coupled by a wireless link.
  • 36. The system of claim 34 wherein said first controller is coupled to said phase shifter by a wire.
  • 37. An antenna control arrangement for use in or with a cellular base station telecommunication system, the system having an electromechanical phase shifter and an antenna with a plurality of radiating elements coupled to a feed network, the control arrangement comprising a hierarchical organization of controllers coupled to and operatively controlling said electromechanical phase shifter.
  • 38. The control arrangement defined by claim 37 further including a first controller operatively coupled to and controlling said phase shifter, and a second controller operatively coupled to and controlling said first controller.
  • 39. The control arrangement defined by claim 38 wherein said first controller is located near said antenna, and wherein said second controller is located remotely from said first controller.
  • 40. The control arrangement defined by claim 38 wherein said first and second controllers are coupled by a wireless link.
  • 41. The control arrangement of claim 37 wherein at least said second controller is a personal computer.
  • 42. The control arrangement of claim 37 wherein at least said first controller is a portable or handheld device.
  • 43. An antenna control arrangement for use in or with a cellular base station telecommunication system, the antenna control arrangement comprising:an antenna with a plurality of radiating elements; the antenna coupled to a feed network having a power-dividing differential electromechanical phase shifter; and first and second controllers for communicating control signals to said electromechanical phase shifter.
  • 44. The control arrangement of claim 43 wherein at least one of said first and second controllers is remotely located remotely from said antenna control arrangement.
  • 45. The control arrangement of claim 43 wherein at least said second controller is a personal computer.
  • 46. The control arrangement of claim 43 wherein at least said first controller is a portable or handheld device.
  • 47. A cellular base station telecommunication system having an antenna with a plurality of radiating elements coupled to a feed network, the system comprising:an electromechanical phase shifter having at least one movable component such that a relative displacement of the at least one moveable component varies a physical path length of signals supplied to at least selected radiating elements; a motor coupled to at least one of said moveable components, and a first controller configured to provide drive signals to said motor.
  • 48. The system of claim 47 wherein said motor is a stepper motor.
  • 49. The system of claim 48 wherein said first controller is configured to supply a predetermined number of drive pulses to said stepper motor.
  • 50. The system of claim 47 wherein said motor is located on said antenna.
  • 51. The system of claim 47 wherein said motor is mechanically coupled to said phase shifter and drives said phase shifter.
  • 52. The system of claim 47 wherein said first controller is remotely located from said antenna.
  • 53. The system of claim 47 further including a second controller operatively coupled to and controlling said first controller.
  • 54. The system of claim 53 wherein the second controller is a portable or handheld device.
  • 55. A cellular base station telecommunication system, the system developing a beam, the system comprising:an antenna having a plurality of radiating elements; a signal feed network operatively coupled to said radiating elements; an electromechanical phase shifter formed as part of said signal feed network; and a portable or handheld controller configured to control said phase shifter.
  • 56. A method for adjusting a beam of a cellular base station telecommunication system, the system having an antenna with a plurality of radiating elements driven through a signal feed network to develop the beam, a method comprising the steps of:providing an electromechanical phase shifter that forms a part of the signal feed network; and controlling said phase shifter with a portable or handheld controller.
Priority Claims (2)
Number Date Country Kind
264864 Nov 1994 NZ
272778 Aug 1995 NZ
Parent Case Info

This is a continuation of application Ser. No. 09/713,614, filed Nov. 15, 2000, entitled Antenna Control System, now U.S. Pat. No. 6,346,924, which is a continuation of application Ser. No. 08/817,445, filed Oct. 16, 1995, entitled Antenna Control System, now U.S. Pat. No. 6,198,458 B1, which is a 371 of PCT/NZ95/00106, filed Oct. 16, 1995.

US Referenced Citations (53)
Number Name Date Kind
2041600 Friis May 1936 A
2432134 Bagnall Dec 1947 A
2540696 Smith, Jr. Feb 1951 A
2596966 Lindsay, Jr. May 1952 A
2648000 White Aug 1953 A
2773254 Engelmann Dec 1956 A
2836814 Nail May 1958 A
2968808 Russell Jan 1961 A
3032759 Ashby May 1962 A
3032763 Sletten May 1962 A
3277481 Robin et al. Oct 1966 A
3969729 Nemit Jul 1976 A
4129872 Toman Dec 1978 A
4176354 Hsiao et al. Nov 1979 A
4241352 Alspaugh et al. Dec 1980 A
4249181 Lee Feb 1981 A
4427984 Anderson Jan 1984 A
4451699 Gruenberg May 1984 A
4532518 Gaglione et al. Jul 1985 A
4564824 Boyd, Jr. Jan 1986 A
4575697 Rao et al. Mar 1986 A
4652887 Cresswell Mar 1987 A
4714930 Winter et al. Dec 1987 A
4717918 Finken Jan 1988 A
4768001 Chan-Son-Lint et al. Aug 1988 A
4779097 Morchin Oct 1988 A
4788515 Wong et al. Nov 1988 A
4791428 Anderson Dec 1988 A
4804899 Wurdack et al. Feb 1989 A
4814774 Herczfeld Mar 1989 A
4821596 Eklund Apr 1989 A
4881082 Graziano Nov 1989 A
5162803 Chen Nov 1992 A
5175556 Berkowitz Dec 1992 A
5181042 Kaise et al. Jan 1993 A
5184140 Hariu et al. Feb 1993 A
5214364 Perdue et al. May 1993 A
5281974 Kuramoto et al. Jan 1994 A
5440318 Butland et al. Aug 1995 A
5488737 Harbin et al. Jan 1996 A
5512914 Hadzoglou et al. Apr 1996 A
5551060 Fujii et al. Aug 1996 A
5596329 Searle et al. Jan 1997 A
5617103 Koscica et al. Apr 1997 A
5659886 Taira et al. Aug 1997 A
5798675 Drach Aug 1998 A
5801600 Butland et al. Sep 1998 A
5805996 Salmela Sep 1998 A
5818385 Bartholomew Oct 1998 A
5905462 Hampel et al. May 1999 A
5995062 Denney et al. Nov 1999 A
6188373 Martek Feb 2001 B1
6198458 Heinz et al. Mar 2001 B1
Foreign Referenced Citations (47)
Number Date Country
3874693 Jul 1993 AU
4162593 Jan 1994 AU
8005794 Apr 1996 AU
3322-986 Jun 1983 DE
3323-234 Jun 1983 DE
3323 234 Oct 1985 DE
137-562 Oct 1983 EP
0 137 562 Apr 1985 EP
241-153 Apr 1986 EP
0 241 153 Oct 1987 EP
357-165 Aug 1988 EP
398-637 May 1989 EP
0 357 165 Mar 1990 EP
0 398 637 Nov 1990 EP
0 423 512 Apr 1991 EP
0 540 387 May 1993 EP
0 588 179 Mar 1994 EP
0 593 822 Apr 1994 EP
0 595 726 May 1994 EP
0 618 639 Oct 1994 EP
0 616 741 Nov 1995 EP
2 581 255 Oct 1986 FR
1 314 693 Apr 1973 GB
2 035 700 Jun 1980 GB
2 158 996 Nov 1985 GB
2 159 333 Nov 1985 GB
2 165 397 Apr 1986 GB
2 196 484 Apr 1988 GB
2 205 946 Dec 1988 GB
2 232 536 Dec 1990 GB
61-172411 Aug 1986 JP
1-120906 May 1989 JP
2-121504 May 1990 JP
2-174402 May 1990 JP
02 174302 Jul 1990 JP
02 174403 Jul 1990 JP
2-290306 Nov 1990 JP
4-286407 Oct 1992 JP
5-121915 May 1993 JP
5-191129 Jul 1993 JP
6-196927 Jul 1994 JP
264864 Nov 1994 NZ
272778 Aug 1995 NZ
WO 8808621 Nov 1988 WO
WO 9216061 Sep 1992 WO
WO 9312587 Jun 1993 WO
WO 9510862 Apr 1995 WO
Non-Patent Literature Citations (15)
Entry
Variable-Elevation Beam-Aerial Systems for 1½ Metres, Journal IEE Part IIIA, vol. 93, 1946, Bacon, G.E.
Radar Antennas, Bell Systems Technical Journal, vol. 26, Apr. 1947, pp. 219 to 317, Friis, H.T. and Lewis, W.D.
The Sydney University Cross-Type Radio Telescope, Proceedings of the IRE Australia, Feb., 1963, pp. 156 to 165, Mills, B.Y., et al.
“Microwave Scanning Systems” published about 1985, pp. 48 to 131.
“Low Sielobe and Titled Beam Base-Station Antennas for Smaller-Cell Systems,” published in or about 1989, Yamada & Kijima, NTT Radio Communication Systems Laboratories, pp. 138 to 141.
“Electrical Downtilt Through Beam-Steering versus Mechanical Downtilt,” G. Wilson, published May 18, 1992, pp. 1-4.
Mobile Telephone Panel Array (MTPA) Antenna: Field Adjustable Downtilt Models published in Australia on or about May 4, 1994.
Mobile Telephone Panel Array (MTPA) Antenna: VARITILT Continuously Variable Electrical Downtilt Models (including specifications sheet) published in Australia on or about Sep. 1994.
Supplementary European Search Report for Application No. EP 95 93 3674 dated Jan. 9, 1999.
International Search Report for PCT/NZ 95/00106 mailed Jan. 23, 1996.
European Search Report for Application No. EP 02 01 0597.
Beam Steering of Planar Phased Arrays -T.C. Cheston, John Hopkins University, Applied Physics Laboratory (Chapter in Phased Array Antennas, Oliner & Knittel 1972).
Microstrip Base Station Antennas for Cellular Communication, Strickland et al., 1991 IEEE.
Antennas, NIG Technical Reports vol. 57, Mar. 8-11, 1977 (including original in German and complete translation into English).
PCT International Search Report for International Application No. PCT/US02/01993, which is a related patent application.
Continuations (2)
Number Date Country
Parent 09/713614 Nov 2000 US
Child 10/073806 US
Parent 08/817445 US
Child 09/713614 US