Antenna system for use in a wireless communication system

• US 6,504,510 B2
• Filed: 04/06/2001
• Issued: 01/07/2003
• Est. Priority Date: 11/03/2000
• Status: Expired due to Fees

• Current Assignee: KMW Incorporated
• Original Assignee: KMW Incorporated
• Inventors: Kim, Duk-Yong
• Primary Examiner(s): Wong, Don
• Assistant Examiner(s): VANNUCCI, JAMES
• Application Number:
  US09/826,849
• Publication Number:
  US 20020053995A1
• Time in Patent Office: 641 Days
• Field of Search: 342/372, 342/368, 342/376, 343/702, 343/776, 343/778, 343/853, 343/763, 343/371, 343/373, 333/101, 333/105, 333/125
• US Class Current: 343/702
• CPC Class Codes: H01Q 1/246 specially adapted for base stations
• CPC Class Codes: H01Q 3/26 varying the relative phase or relative amplitude of energisation between two or more active radiating elements; varying the distribution of energy across a radiating aperture H01Q3/12, H01Q3/22, H01Q3/24 take precedence
• CPC Class Codes: H01Q 3/32 by mechanical means
• CPC Class Codes: H01Q 3/38 the phase-shifters being digital

Abstract

An antenna system for use in a wireless communication system includes an array of M×N radiating elements for emitting a beam, an input port for providing signals to the array of M×N radiating elements, M number of first phase shifters for steering the beam on the basis of column by phase shifting the signals from the input port, N number of second phase shifters for steering the beam on the basis of row by phase shifting the signals, N number of switchable dividers for selectively transmitting the signals to a number of transmission lines incorporated into the second phase shifters and M number of combiner/dividers for transmitting the signals from the transmission lines of the second phase shifters to the transmission lines of the first phase shifters. The antenna system can implement a 3-way beam control by utilizing multi-line phase shifters and switchable dividers. Therefore, the antenna system controls cell coverage more flexible than any other prior arts and become friendly with user and the communication environment by utilizing the 3-way beam control. Further, the antenna system can enhance performance and reduce cost by using the multi-line phase shifters.

Claims

1. An antenna system for use in a wireless communication system, comprising:

an array of M×

N radiating elements for emitting a beam, M and N each being a positive integer, respectively;

a feeding network for providing a plurality of signals to the array of M×

N radiating elements;

M first phase shifters for steering the beam on the basis of column by phase shifting the plurality of signals from the feeding network; and

N second phase shifters for steering the beam on the basis of row by phase shifting the plurality of signals from the feeding network,

wherein the feeding network includes;

an input port for receiving the plurality of signals;

N dividers for transmitting the plurality of signals to each of transmission lines of the second phase shifters; and

M combiner/dividers for transmitting the plurality of signals to each of transmission lines of the first phase shifters after passing through the second phase shifters.

2. The antenna system of claim 1, wherein each of the first phase shifters simultaneously phase shifts a first group of N signals selected from the plurality of signals by rotating a dielectric member incorporated into each of the first phase shifters.

3. The antenna system of claim 2, further comprising:

a first rotation apparatus that rotates the dielectric members of the first phase shifters.

4. The antenna system of claim 2, wherein each of the first phase shifters includes:

a dielectric member provided with a first and a second portion, wherein a dielectric constant of the first portion is different from a dielectric constant of the second portion; and

N transmission lines positioned opposite the dielectric member for transmitting the N signals of the first group, wherein each signal is input to one end of a corresponding transmission line and output to a corresponding radiating element after passing through the corresponding transmission line.

5. The antenna system of claim 1, wherein the M and N represent the number of columns and the number of rows, respectively.

6. The antenna system of claim 4, wherein each of the first phase shifters further includes a metal plate provided with a first and a second part on which the transmission lines are formed.

7. The antenna system of claim 6, wherein N/2 transmission lines are formed on the first part and N/2 transmission lines are formed on the second part.

8. The antenna system of claim 7, wherein the transmission lines of the first part is arranged in such a way that they are symmetric with respect to those of the second part, whereby if electrical lengths of the transmission lines of the first part are increased to a predetermined value, those of the second part are decreased to the predetermined value.

9. The antenna system of claim 3, wherein if the first rotation apparatus rotates the dielectric member of the first phase shifter, signals have a symmetry in phase plane with respect to a center point after passing through the first phase shifter.

10. The antenna system of claim 6, wherein each of the combiner/dividers includes:

a combiner provided with N input ports and an output port; and

a divider provided with an input port and N output ports.

11. The antenna system of claim 1, wherein each of the second phase shifters simultaneously phase shifts M signals by rotating a dielectric member incorporated into each of the second phase shifters, the dielectric member being provided with a first and a second portions and a dielectric constant of the first portion being different from a dielectric constant of the second portion.

12. The antenna system of claim 11, further comprising:

a second rotation apparatus that rotates the dielectric members of the second phase shifters.

13. The antenna system of claim 12, wherein each of the second phase shifters includes:

M transmission lines positioned opposite the dielectric member for transmitting the M signals, wherein each of the M signals is input into one end of a corresponding transmission line.

14. The antenna system of claim 13, wherein the second phase shifter further includes a metal plate provided with a first and a second parts on which the transmission lines are formed.

15. The antenna system of claim 14, wherein M/2 transmission lines are formed on the first part and M/2 transmission lines are formed on the second part.

16. The antenna system of claim 15, wherein the transmission lines of the first part is arranged in such a way that they are symmetric with respect to those of the second part, whereby if electrical lengths of the transmission lines of the first part are increased to a predetermined value, those of the second part are decreased to the predetermined value.

17. The antenna system of claim 1, wherein the dividers employ:

N switchable dividers for selectively transmitting the plurality of signals to each of the transmission lines of the second phase shifters.

18. The antenna system of claim 17, wherein each of the switchable dividers includes:

an input port for receiving an input signal;

a common node;

M first transmission lines;

M second transmission lines;

M isolation elements disposed between the first and the second transmission lines, wherein each isolation element is electrically connected to corresponding first and second transmission lines, respectively;

M output ports for outputting M output signals, each of the output ports being connected to a portion between a corresponding isolation element and a corresponding first or second transmission line;

a first switch for selectively switching the input signal to the first transmission lines; and

a second switch for selectively switching the common node to the second transmission lines based on the first switch.

19. The antenna system of claim 18, wherein M is 4 and N is 8 for applying to INT-2000.

20. The antenna system of claim 17, further comprising:

a beam control board for generating control signals to control the switchable dividers, the first phase shifters and the second phase shifters.

21. The antenna system of claim 1, wherein N is 1 and the second phase shifter steers the beam by simultaneously phase shifting the plurality of signals from the feeding network.

22. The antenna system of claim 21, wherein each of the first phase shifters includes:

a dielectric member provided with a first portion and a second portion, wherein a dielectric constant of the first portion is different from a dielectric constant of the second portion; and

N transmission lines positioned opposite the dielectric member for transmitting N signals selected from the plurality of signals, wherein each of the N signals is inputted to one end of a corresponding transmission line and outputted to a corresponding radiating element.

23. The antenna system of claim 22, further comprising:

a rotation apparatus that rotates the dielectric member of each of said first phase shifters.

24. An antenna system for use in a wireless communication system, comprising:

an array of M×

N radiating elements for emitting a beam, M and N being positive integers, respectively;

a switchable divider for selectively providing a plurality of signals to the array of M×

N radiating elements;

a phase shifter for steering the beam on the basis of row by simultaneously phase shifting the plurality of signals from the switchable divider;

M providers for providing the plurality of signals to the array of M×

N radiating elements; and

M phase shifters for steering the beam on the basis of column by phase shifting the plurality of signals from the M providers.

25. The antenna system of claim 24, wherein the switchable divider includes:

an input port for receiving an input signal;

a common node;

M first transmission lines;

M second transmission lines;

M isolation elements disposed between the first and the second transmission lines, wherein each isolation element is electrically connected to corresponding first and second transmission lines, respectively;

M output ports for outputting M output signals, each of the output ports being connected to a portion between a corresponding isolation element and a corresponding first or second transmission line;

a first switch for selectively switching the input signal to the first transmission lines; and

a second switch for selectively switching the common node to the second transmission lines based on the first switch.

26. The antenna system of claim 25, wherein a horizontal width of the beam is controlled by changing M of the switchable divider.

27. An antenna system for use in a wireless communication system, comprising:

an array of M×

N radiating elements for emitting a beam, M and N each being a positive integer, respectively;

a feeding network for providing a plurality of signals to the array of M×

N radiating elements;

M first phase shifters for steering the beam on the basis of column by phase shifting the plurality of signals from the feeding network, wherein each of the first phase shifters simultaneously phase shifts a first group of N signals selected from the plurality of signals by rotating a dielectric member incorporated into each of the first phase shifters;

N second phase shifters for steering the beam on the basis of row by phase shifting the plurality of signals from the feeding network; and

a first rotation apparatus that rotates the dielectric members of the first phase shifters, wherein when the first rotation apparatus rotates the dielectric member of the first phase shifter, signals have a symmetry in a phase plane with respect to a center point after passing through the first phase shifter.

28. The antenna system of claim 27, wherein each of the first phase shifters comprises:

a dielectric member provided with a first and a second portion, wherein a dielectric constant of the first portion is different from that of the second portion; and

N transmission lines positioned opposite the dielectric member for transmitting the N signals of the first group, wherein each signal is input to one end of a corresponding transmission line and output to a corresponding radiating element after passing through the corresponding transmission line.

29. The antenna system of claim 28, wherein each of the first phase shifters further includes a metal plate provided with a first and a second part on which the transmission lines are formed.

30. The antenna system of claim 29, wherein N/2 transmission lines are formed on the first part and N/2 number of transmission lines are formed on the second part.

31. The antenna system of claim 30, wherein the transmission lines of the first part are arranged such that they are symmetric with respect to the transmission lines of the second part, whereby if electrical lengths of the transmission lines of the first part are increased to a predetermined value, the transmission lines of the second part are decreased to the predetermined value.