Systems and methods for frequency reuse in wireless networks

• US 20060205422A1
• Filed: 08/11/2005
• Published: 09/14/2006
• Est. Priority Date: 03/14/2005
• Status: Active Grant

• Current Assignee: Nextel Communications (Deutsche Telekom AG)
• Original Assignee: Nextel Communications (Deutsche Telekom AG)
• Inventors: Thakore, Udit, Hyslop, Douglas A., Starzec, Matthew
• Granted Patent: US 7,751,822 B2
• Time in Patent Office: Days
• US Class Current: 455/509
• CPC Class Codes: H04W 16/00 Network planning, e.g. coverage or traffic planning tools; Network deployment, e.g. resource partitioning or cells structures
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

A frequency reuse scheme that provides high spectral efficiency and reduced interference in areas where cell sites overlap is provided. Three frequencies are allocated per cell site, with each sector employing two frequencies, one frequency being transmitted at a higher power and the second frequency being transmitted at a lower power. The higher power frequency in one sector differs from the higher power frequency employed in the other two sectors, and the lower power frequency used in one sector differs from the lower power frequency used in the other two sectors.

Claims

1. A method for frequency allocation in a wireless network, comprising the acts of:

allocating a first frequency at a first power level and a second frequency at a second power level in a first sector of a cell site;

allocating a third frequency at the first power level and the first frequency at the second power level in a second sector of the cell site; and

allocating the second frequency at the first power level and the third frequency at the second power level in a third sector of the cell site, wherein each sector is allocated at most two frequencies.

2. The method of claim 1, wherein the first power level is higher than the second power level.

3. The method of claim 1, further comprising the acts of:

allocating the first frequency at the first power level and the second frequency at the second power level in a first sector of another cell site;

allocating the third frequency at the first power level and the first frequency at the second power level in a second sector of the another cell site; and

allocating the second frequency at the first power level and the third frequency at the second power level in a third sector of the another cell site.

4. The method of claim 3, wherein a portion of the third sector of the first cell site overlaps with a portion of the second sector of the another cell site, such that the first cell site transmits the second frequency and the another cell site transmits the third frequency in the area of overlap between the cells sites.

5. The method of claim 1, wherein the wireless network employs orthogonal frequency division multiple access (OFDMA) over an air interface.

6. The method of claim 1, wherein the wireless network employs code division multiple access (CDMA) over an air interface.

7. A method for frequency allocation in a wireless network, comprising the acts of:

allocating a first frequency at a first power level and a second frequency at a second power level in a first sector of a cell site;

allocating a third frequency at the first power level and the first frequency at the second power level in a second sector of the cell site; and

allocating the second frequency at the first power level and the third frequency at the second power level in a third sector of the cell site, wherein each sector communicates using only the first and second power levels.

8. The method of claim 7, wherein the first power level is higher than the second power level.

9. The method of claim 7, further comprising the acts of:

allocating the first frequency at the first power level and the second frequency at the second power level in a first sector of another cell site;

allocating the third frequency at the first power level and the first frequency at the second power level in a second sector of the another cell site; and

allocating the second frequency at the first power level and the third frequency at the second power level in a third sector of the another cell site.

10. The method of claim 9, wherein a portion of the third sector of the first cell site overlaps with a portion of the second sector of the another cell site, such that the first cell site transmits the second frequency and the another cell site transmits the third frequency in the area of overlap between the cells sites.

11. The method of claim 7, wherein the wireless network employs orthogonal frequency division multiple access (OFDMA) over an air interface.

12. The method of claim 7, wherein the wireless network employs code division multiple access (CDMA) over an air interface.

13. A method for frequency allocation in a wireless network, comprising the acts of:

allocating a first pair of frequencies to a first sector of a cell site;

allocating a second pair of frequencies to a second sector of the cell site;

allocating a third pair of frequencies to a third sector of the cell site,

wherein each pair of frequencies are allocated at first and second power levels and at least one frequency of the pair of frequencies allocated to the first and second sectors is not allocated to the third sector.

14. The method of claim 13, wherein the first power level is higher than the second power level.

15. The method of claim 13, further comprising the acts of:

allocating a first pair of frequencies to a first sector of another cell site;

allocating a second pair of frequencies to a second sector of the another cell site;

allocating a third pair of frequencies to a third sector of the another cell site,

wherein at least one frequency of the pair of frequencies allocated to the first and second sectors of the another cell site is not allocated to the third sector of the another cell site.

16. The method of claim 15, wherein a portion of the third sector of the first cell site overlaps with a portion of the second sector of the another cell site, such that the first cell site transmits on a different frequency than the another cell site in the area of overlap between the cells sites.

17. The method of claim 13, wherein the wireless network employs orthogonal frequency division multiple access (OFDMA) over an air interface.

18. The method of claim 13, wherein the wireless network employs code division multiple access (CDMA) over an air interface.