Cellular Antenna

Abstract

An antenna for communicating with mobile devices in a land-based cellular communication system via an antenna beam having a width, azimuth angle and downtilt angle. The antenna includes: a two dimensional array of radiating elements ( 31 - 34 ); and a feed network ( 35 - 39 ) from a feed line to the radiating elements. The feed network includes: downtilt phase shifting means ( 35,36 ) for varying the phase of signals supplied to or received from the radiating elements so as to vary the downtilt angle of the antenna beam; azimuth phase shifting ( 38,39 ) means for varying the phase of signals supplied to or received from the radiating elements so as to vary the azimuth angle of the antenna beam; and beam width adjustment means ( 37 ) for varying the power or phase of signals supplied to or received from the radiating elements so as to vary the width of the antenna beam.

1 . An antenna for communicating with mobile devices in a land-based cellular communication system via an antenna beam having a width, azimuth angle and downtilt angle, the antenna including:
 a two dimensional array of radiating elements; and   a feed network from a feed line to the radiating elements, the feed network including:   downtilt phase shifting means for vary the phase of signals supplied to or received form the radiating elements so as to vary the downtilt angle of the antenna beam;   azimuth phase shifting means for varying the phase of signals supplied to or received from the radiating elements so as to vary the azimuth angle of the antenna beam; and   beam width adjustment means for varying the power or phase of signals supplied to or received form the radiating elements so as to vary the width of the antenna beam   
     
     
         2 . The antenna of  claim 1  wherein the beam width adjustment means includes power dividing means for varying the division of power between radiating elements so as to vary the width of the antenna beam. 
     
     
         3 . The antenna of  claim 2  wherein the power dividing means divides power between one or more central radiating elements and two or more outer radiating elements positioned in the array on opposite sides of the central radiating elements(s). 
     
     
         4 . The antenna of  claim 2  or  3  wherein the power dividing means is substantially non-attenuating. 
     
     
         5 . The antenna of  claim 3  or  4  wherein the downtilt phase shifting means adjusts the relative phase between the pair of outer radiating elements. 
     
     
         6 . The antenna of  claim 3 ,  4  or  5  wherein the phase relationship between the central radiating elements(s) and the power dividing means is substantially fixed for all values of downtilt and azimuth angle. 
     
     
         7 . The antenna of  claim 3 ,  4 ,  5  or  6  wherein the azimuth phase shifting means adjusts the relative phase between the pair of outer radiating elements. 
     
     
         8 . The antenna of  claim 1  wherein the beam width adjustment means includes means for varying the phase of signals supplied to or received from the radiating elements so as to vary the width of the antenna beam. 
     
     
         9 . The antenna of any of the preceding claims wherein the array includes at least three rows and at least three columns of radiating elements. 
     
     
         10 . The antenna of any of the preceding claims wherein the beam width is adjustable in an azimuthal direction. 
     
     
         11 . An antenna for communicating with mobile devices in a land-based cellular communication system via an antenna beam having a width and an angle, the antenna including:
 a plurality of radiating elements; and   a feed network from a feed line to the radiating elements, the feed network including:   power dividing means for varying the division of power between radiating elements so as to vary the width of the antenna beam; and   phase shifting means for varying the phase of signals supplied to or received from the radiating elements so as to vary the angle of the antenna beam.   
     
     
         12 . The antenna of  claim 11  wherein the power dividing means divides power between one or more central radiating elements and two or more outer radiating elements positioned on opposite sides of the central radiating elements(s). 
     
     
         13 . The antenna of  claim 11  or  12  wherein the power dividing means is substantially non-attenuating. 
     
     
         14 . The antenna of  claim 12  wherein the phase shifting means adjusts the relative phase between the pair of outer radiating elements. 
     
     
         15 . The antenna of  claim 14  wherein the phase relationship between the central radiating elements(s) and the power dividing means is substantially fixed for all values of beam angle. 
     
     
         16 . The antenna of any one of  claims 12  to  15  wherein the angle is an azimuth angle 
     
     
         17 . The antenna of any one of  claims 12  to  16  wherein the angle is a downtilt angle. 
     
     
         18 . The antenna of  claim 16  and  17  wherein the phase shifting means can vary the azimuth and downtilt angle of the antenna beam. 
     
     
         19  the antenna of any of the preceding claims wherein the or each phase shifting means is adjusted by varying the relative position of two or more phase shifting components. 
     
     
         20 . A land-based antenna system including one or more antennas according to any of the preceding claims; and an encoder for encoding downlink signals for transmission to the radiating elements according to a code-division multiplexing (CDMA) scheme. 
     
     
         21 . A land-based antenna system including one or more antennas according to any of the preceding claims; and a decoder for decoding uplink signals received from the radiating elements according to a code-division multiplexing (CDMA) scheme. 
     
     
         22 . The land-based antenna system of  claim 20  or  21  including control means adapted to provide signals to the antenna(s) to adjust a characteristic of the antenna beam. 
     
     
         23 . A land-based antenna system including one or more antennas according to any of  claims 1  to  19 ; and control means adapted to provide signals to the antenna(s) to adjust a characteristic of the antenna beam. 
     
     
         24 . The system of  claim 23  wherein the control means comprises a local receiver adapted to receive commands from a remote control centre. 
     
     
         25 . The system of  claim 23  or  24  including a plurality of antennas, and wherein the control means includes:
 means for receiving a command to change a beam characteristic of one of the antennas;   means for calculating the beam characteristic required for all of the antennas to achieve a desired coverage; and   means for adjusting one or more beam characteristic of each antenna as required to achieve the desired coverage.   
     
     
         26 . The system of  claim 22 ,  23 ,  24 ,  25  or  26  wherein the control means includes:
 graphical user interface means for graphically displaying parameters of the configuration of a plurality of antennas wherein, via use of an input device, graphical elements may be manipulated to adjust parameters of the configuration; and   communication means for sending control signals to an actuation means to adjust parameters of an antenna in accordance with those displayed by the graphical user interface.   
     
     
         27 . An antenna system for communicating with mobile devices in a land-based cellular communication system via an antenna beam, the antenna system including:
 an antenna having a plurality of radiating elements, and an RF feed line for transmitting signals to and/or from the radiating elements;   transmission means coupled to the RF feed line; and   control means for adjusting a characteristic of the antenna beam in accordance with control data received from the transmission means via the RF feed line.   
     
     
         28 . An antenna system for communicating with mobile devices in a land-based cellular communication system, the antenna system including:
 a plurality of antennas each having phase shifting means for adjusting a characteristics of the beam of the antenna, each antenna being provided at an elevated height on a structure; and   an antenna control system for controlling the phase shifting means, the antenna control system being provided at an elevated height near the antennas.   
     
     
         29 . An antenna system for communicating with mobile devices in a land-based cellular communication system, the antenna system including:
 a plurality of radiating elements;   one or more phase shifter provided in a feed network to the plurality of radiating elements for adjusting a characteristic of the beam of the antenna; and   control means for driving electromechanical means associated with each phase shifter wherein the control means includes processing means to control the antenna in accordance with control data supplied thereto.   
     
     
         30 . The system of any of  claims 25  to  29  wherein the antenna is an antenna according to any of  claim 1  to  19 . 
     
     
         31 . A land-based cellular communication system including one or more systems according to any of  claims 20  to  30 ; and a remote control centre for issuing commands to each system to adjust antenna beam characteristics of each system. 
     
     
         32 . An antenna control system for controlling the beam characteristics of a plurality of antennas which communicate with mobile devices in a land-based cellular communication system, the antenna control system including:
 means for receiving a command to change a beam characteristic of one of the antennas;   means for calculating the beam characteristics required for all of the antennas to achieve a desired coverage; and   means for adjusting one or more beam characteristic of each antenna as required to achieve the desired coverage.   
     
     
         33 . A computer for controlling an antenna which communicates with mobile devices in a land-based cellular communication system, the computer including:
 graphical user interface means for graphically displaying parameters of the configuration of a plurality of antennas wherein, via use of an input device, graphical elements may be manipulated to adjust parameters of the configuration; and   communication means for sending control signal to an actuation means to adjust parameters of an antenna in accordance with those displayed by the graphical user interface.   
     
     
         34 . The hand held device including the computer of  claim 33 .