Antenna device, a communication device including such an antenna device and a method of operating the communication device

Abstract

An antenna device includes a first and a second internal antenna element and a common ground plane. The first element has an upper and a lower end portion. The first antenna element is adapted for use with a cellular mobile phone system and the second antenna element is adapted for use with a GPS system. To that end, the second element is elongated and adapted to receive circularly polarized radio signals by operation with linear polarization. This provides for a compact antenna device adapted for use with more than one communication system.

1. An antenna device for a portable radio communication device, comprising:
 a ground conductor positioned essentially in a plane and having front and back surfaces and an upper and a lower end portion,  
 a first antenna element having a  an upper end portion and a lower end portion, said first element being essentially parallel to and spaced apart from said back surface of said ground conductor by first distance, wherein said first antenna element is adapted to receive linearly polarized radio signals; and  
 a second antenna element being spaced apart from said upper end portion of said ground conductor by a second distance, and said second antenna element being spaced apart from said upper end portion of said first antenna element by a third distance, wherein said second antenna element is elongated and is adapted solely to receive circularly polarized radio signals by operation with linear polarization.  
 
     
     
       2. The antenna device according to  claim 1 , wherein said second antenna element is closer to said upper end portion of said first antenna element than said lower end portion of said first antenna element. 
     
     
       3. The antenna device according to  claim 1 , wherein said second antenna element is positioned essentially in the plane of said ground conductor. 
     
     
       4. The antenna device according to  claim 1 , wherein said second antenna element is essentially parallel to said upper end portion of said ground conductor. 
     
     
       5. The antenna device according to  claim 1 , wherein said upper end portion of said ground conductor is essentially straight. 
     
     
       6. The antenna device according to  claim 1 , wherein said second antenna element is essentially strip shaped. 
     
     
       7. The antenna device according to  claim 6 , wherein said second antenna element is positioned in a plane essentially perpendicular to said plane of said ground conductor. 
     
     
       8. The antenna device according to  claim 1 , wherein said second antenna element is meander shaped. 
     
     
       9. The antenna device according to  claim 1 , wherein said second antenna element is wire shaped. 
     
     
       10. The antenna device according to  claim 1 , wherein said second antenna element has a length adapted for use with the GPS system. 
     
     
       11. The antenna device according to  claim 10 , wherein said second antenna element has a length of about one-quarter wavelength of a GPS signal. 
     
     
       12. The antenna device according to  claim 1 , wherein at least one of said first and second antenna elements is provided with a grounding portion. 
     
     
       13. The antenna device according to  claim 1 , wherein said first and second antenna elements, have first and second feed portions respectively each of said feed portions are connected to separate electronic circuitry. 
     
     
       14. The antenna device according to  claim 1 , wherein said first distance is shorter than said third distance. 
     
     
       15. The antenna device according to  claim 1 , wherein said second distance is shorter than said third distance. 
     
     
       16. The antenna device according to  claim 1 , wherein said first antenna element constitutes part of a planar inverted F antenna. 
     
     
       17. A portable radio communication device, comprising:
 a housing;  
 a user interface; and  
 an antenna device, said antenna device further comprising: 
 a ground conductor being positioned essentially in a plane and having front and back surfaces and an upper and a lower end portion,  
 a first antenna element having an upper end portion and a lower end portion, said first element being essentially parallel to and spaced apart from, said back surface of said ground conductor by first distance, wherein said first antenna element is adapted to receive linearly polarized radio signals; and  
 a second antenna element being spaced apart from said upper end portion of said ground conductor by a second distance, and said second antenna element being spaced apart form said upper end portion of said first antenna element by a third distance, wherein said second antenna element is elongated and is adapted solely to receive circularly polarized radio signals by operation with linear polarization.  
 
 
     
     
       18. The portable radio communication device according to  claim 17 , wherein said antenna device is positioned in the upper portion of the radio communication device. 
     
     
       19. The portable radio communication device according to  claim 18 , wherein said second antenna element of said antenna device is positioned in the top of the radio communication device. 
     
     
       20. An antenna device for a portable radio communication device, comprising:
   a ground conductor positioned essentially in a plane,        an antenna element being spaced apart from said ground conductor and meander shaped,        wherein said antenna element is elongated and is adapted solely to receive circularly polarized radio signals by operation with linear polarization.     
     
     
       21. The antenna device according to  claim 20 , wherein said antenna element is essentially strip shaped. 
     
     
       22. The antenna device according to  claim 20 , wherein said antenna element is positioned in a plane essentially perpendicular to said plane of said ground conductor. 
     
     
       23. The antenna device according to  claim 20 , wherein said antenna element is wire shaped. 
     
     
       24. The antenna device according to  claim 20 , wherein said antenna element has a length adapted for use with the GPS system. 
     
     
       25. The antenna device according to  claim 24 , wherein said antenna element has a length of about one- quarter wavelength of a GPS signal.   
     
     
       26. A portable radio communication device, comprising:
   a housing;        a user interface; and        an antenna device, said antenna device further comprising:      a ground conductor, and        an antenna element being spaced apart from said ground conductor and meander shaped, wherein said antenna element is elongated and is adapted solely to receive circularly polarized radio signals by operation with linear polarization.       
     
     
       27. The portable radio communication device according to  claim 26 , wherein said antenna device is positioned in the upper portion of the radio communication device.