Method and system for minimizing overlap nulling in switched beams

• US 20040127174A1
• Filed: 12/30/2002
• Published: 07/01/2004
• Est. Priority Date: 12/30/2002
• Status: Active Grant

• Current Assignee: Google Technology Holdings LLC (Alphabet Inc.)
• Original Assignee: Motorola, Inc. (Motorola Solutions, Inc.)
• Inventors: Frank, Colin, Touvannas, John, Luz, Yuda, Chen, Jason Jiangnan
• Granted Patent: US 7,272,364 B2
• Time in Patent Office: Days
• US Class Current: 455/101
• CPC Class Codes: H01Q 1/246 specially adapted for base stations
• CPC Class Codes: H01Q 25/00 Antennas or antenna systems providing at least two radiating patterns arrangements for changing or varying the orientation or the shape of the directional pattern H01Q3/00
• CPC Class Codes: H01Q 3/40 with phasing matrix

Abstract

A wireless system, which minimizes nulls within the wireless system, while simultaneously providing diversity. A wireless system will now have increased capacity and coverage due to an enhanced signal to interference ratio in the areas of beam overlap. The system uses time or frequency offset on the signals input to an antenna to minimize interference in the regions of beam overlap. Additionally, polarization diversity can be introduced using Butler Matrices in conjunction with array elements to enhance the interference reduction.

Claims

1. A system, comprising:

an antenna;

a first circuit operable to provide a first signal to said antenna; and

a second circuit operable to provide a second signal to said antenna, the second signal being offset in time from the first signal,

wherein said antenna is operable to transmit a first beam corresponding to the first signal, said antenna is further operable to transmit a second beam corresponding to the second signal and partially overlapping the first beam, the second beam being offset in time to the first beam to thereby minimize a formation of nulls within the first beam and the second beam.

2. The system of claim 1, further comprising:

a third circuit operable to provide a third signal to said antenna, the third signal being offset in time from the second signal,

wherein said antenna is operable to transmit a third beam corresponding to the third signal and partially overlapping the second beam, the third beam being offset in time to the second beam to thereby minimize a formation of nulls within the second beam and the third beam.

3. The system of claim 2, wherein said antenna includes:

a first Butler matrix and a first element array collectively operable to transmit the first beam and the third beam with a first polarization.

4. The system of claim 2, further comprising:

a fourth circuit operable to provide a fourth signal to said antenna, the fourth signal being offset in time from the third signal,

wherein said antenna is operable to transmit a fourth beam corresponding to the fourth signal and partially overlapping the third beam, the fourth beam being offset in time to the third beam to thereby minimize a formation of nulls within the third beam and the fourth beam.

5. The system of claim 4, wherein said antenna further includes:

a first Butler matrix and a first element array collectively operable to transmit the first beam and the third beam with a first polarization; and

a second Butler matrix and a second element array collectively operable to transmit the second beam and the fourth beam with a second polarization,

wherein the second polarization is orthogonal to the first polarization to thereby further minimize a formation of nulls within the first beam, the second beam, the third beam, and the fourth beam.

6. A system, comprising:

an antenna;

a first circuit operable to provide a first signal to said antenna; and

a second circuit operable to provide a second signal to said antenna, the second signal being offset in frequency from the first signal,

wherein said antenna is operable to transmit a first beam corresponding to the first signal, said antenna is further operable to transmit a second beam corresponding to the second signal and partially overlapping the first beam, the second beam being offset in frequency to the first beam to thereby minimize a formation of nulls within the first beam and the second beam.

7. The system of claim 6, further comprising:

a third circuit operable to provide a third signal to said antenna, the third signal being offset in frequency from the second signal,

wherein said antenna is operable to transmit a third beam corresponding to the third signal and partially overlapping the second beam, the third beam being offset in frequency to the second beam to thereby minimize a formation of nulls within the second beam and the third beam.

8. The system of claim 7, further comprising:

a first Butler matrix and a first element array collectively operable to transmit the first beam and the third beam with a first polarization.

9. The system of claim 7, further comprising:

a fourth circuit operable to provide a fourth signal to said antenna, the fourth signal being offset in frequency from the third signal,

wherein said antenna is operable to transmits a fourth beam corresponding to the fourth signal and partially overlapping the third beam, the fourth beam being offset in frequency to the third beam to thereby minimize a formation of nulls within the third beam and the fourth beam.

10. The system of claim 9, wherein said antenna further includes:

a first Butler matrix and a first element array collectively operable to transmit the first beam and the third beam with a first polarization; and

a second Butler matrix and a second element array collectively operable to transmit the second beam and the fourth beam with a second polarization,

wherein the second polarization is orthogonal to the first polarization to thereby further minimize a formation of nulls within the first beam, the second beam, the third beam, and the fourth beam.

11. A system, comprising:

an antenna;

a plurality of circuits operable to provide a plurality of signals to said antenna, wherein a first signal in each pair of adjacent signals is offset in time from a second signal in each pair of adjacent signals;

wherein said antenna is operable to transmit spatially distinct beams corresponding to the plurality of signals, and

wherein a first beam in each pair of adjacent beams partially overlaps and is offset in time from a second beam in each pair of adjacent beams to thereby minimize a formation of nulls in the spatially distinct beams.

12. A system, comprising:

an antenna;

a plurality of circuits operable to provide a plurality of signals to said antenna, wherein a first signal in each pair of adjacent signals is offset in frequency from a second signal in each pair of adjacent signals;

wherein said antenna is operable to transmit spatially distinct beams corresponding to the plurality of signals, and

wherein a first beam in each pair of adjacent beams partially overlaps and is offset in frequency from a second beam in each pair of adjacent beams to thereby minimize a formation of nulls in the spatially distinct beams.