Method and system for defining additional spread spectrum channels within a coverage area of an existing wireless network

• US 7,555,028 B2
• Filed: 05/03/2002
• Issued: 06/30/2009
• Est. Priority Date: 05/03/2002
• Status: Expired due to Fees

• Current Assignee: Sprint Spectrum LLC (Deutsche Telekom AG)
• Original Assignee: Sprint Spectrum LP (Deutsche Telekom AG)
• Inventors: Oh, Dae-Sik, Yarkosky, Mark
• Primary Examiner(s): VO, DON NGUYEN
• Application Number:
  US10/138,203
• Publication Number:
  US 20070297490A1
• Time in Patent Office: 2,615 Days
• Field of Search: 375/130, 375/141, 375/145, 375/140, 370/320, 370/335, 370/342, 370/441, 370/347, 455436-449, 455/454, 455/422.1, 455/450, 455/427
• US Class Current: 375/130
• CPC Class Codes: H04B 1/69 Spread spectrum techniques
• CPC Class Codes: H04B 1/7097 Interference-related aspects

Abstract

A method and system for defining additional spread spectrum channels within a coverage area already served by an existing wireless network. A first spread spectrum channel may be defined by a first range of frequencies. A second spread spectrum channel may be defined by a second range of frequencies. A portion of the first range of frequencies may overlap with a portion of the second range of frequencies. The overlap may be such that the first spread spectrum channel and the second spread spectrum channel may carry signals that minimally interfere with each other.

Claims

1. A method of providing wireless network service, the method comprising:

establishing a first spread spectrum channel defined by a first range of frequencies;

establishing a second spread spectrum channel defined by a second range of frequencies, wherein the first range of frequencies overlaps with a portion of the second range of frequencies and the portion of the second range of frequencies that overlaps with the first range of frequencies is approximately half of the second range of frequencies;

communicating a first signal over the first range of frequencies with a first wireless terminal; and

communicating a second signal over the second range of frequencies with a second wireless terminal, wherein the first signal has a first power level, the second signal has a second power level, and a difference between the first power level and the second power level is between zero and approximately 5 dBm.

2. The method of claim 1, wherein the first range of frequencies has a first center frequency, the second range of frequencies has a second center frequency, and the first center frequency is offset from the second center frequency by approximately half of the second range of frequencies.

3. The method of claim 1, wherein the first range of frequencies is approximately 1.25 MHz, the second range of frequencies is approximately 1.25 MHz, and the portion of the second range of frequencies that overlaps with the first range of frequencies is approximately 0.625 MHz.

4. The method of claim 1, wherein the first spread spectrum channel and the second spread spectrum channel are CDMA channels.

5. A system, comprising:

a first base station using a first spread spectrum channel defined by a first range of frequencies to communicate a first signal; and

a second base station, serving an area served by the first base station, using a second spread spectrum channel defined by a second range of frequencies to communicate a second signal, wherein the first range of frequencies overlaps with a portion of the second range of frequencies, and wherein the first signal has a first power level at the second base station, the second base station transmits the second signal at a second power level, and a difference between the first power level and the second power level is between zero and approximately 5 dBm.

6. The system of claim 5, wherein the portion of the second range of frequencies that overlaps with the first range of frequencies is a greater of (i) approximately ½

the first range of frequencies or (ii) approximately ½

the second range of frequencies.

7. The system of claim 5, wherein the portion of the second range of frequencies that overlaps with the first range of frequencies is defined by an offset between a first center frequency of the first spread spectrum channel and a second center frequency of the second spread spectrum channel, the offset being a greater of (i) approximately ½

the first range of frequencies or (ii) approximately ½

the second range of frequencies.

8. The system of claim 5, wherein the first range of frequencies is approximately 1.25 MHz, the second range of frequencies is approximately 1.25 MHz, and the portion of the second range of frequencies that overlaps with the first range of frequencies is approximately 0.625 MHz.

9. The system of claim 5, wherein the first spread spectrum channel and the second spread spectrum channel are CDMA channels.

10. In an area served by a first base station, the first base station using a first spread spectrum channel to communicate a first signal, the first spread spectrum channel being defined by a first range of frequencies, a system comprising:

a second base station, the second base station using a second spread spectrum channel to communicate a second signal, the second spread spectrum channel being defined by a second range of frequencies, wherein the second range of frequencies overlaps with a portion of the first range of frequencies, and wherein the first signal has a first power level at the second base station, the second base station transmits the second signal at a second power level, and a difference between the first power level and second power level is between zero and approximately 5 dBm.

11. The system of claim 10, wherein the portion of the second range of frequencies that overlaps with the first range of frequencies is a greater of (i) approximately ½

the first range of frequencies or (ii) approximately ½

the second range of frequencies.

12. The system of claim 10, wherein the portion of the second range of frequencies that overlaps with the first range of frequencies is defined by an offset between a first center frequency of the first spread spectrum channel and a second center frequency of the second spread spectrum channel, the offset being a greater of (i) approximately ½

the first range of frequencies or (ii) approximately ½

the second range of frequencies.

13. The system of claim 10, wherein the first range of frequencies is approximately 1.25 MHz, the second range of frequencies is approximately 1.25 MHz, and the portion of the second range of frequencies that overlaps with the first range of frequencies is approximately 0.625 MHz.

14. The system of claim 10, wherein the first spread spectrum channel and the second spread spectrum channel are CDMA channels.

15. A method of providing wireless network service, the method comprising:

establishing a first spread spectrum channel defined by a first range of frequencies;

establishing a second spread spectrum channel defined by a second range of frequencies, wherein the first range of frequencies overlaps with a portion of the second range of frequencies;

transmitting from a first base station a first signal over the first range of frequencies; and

transmitting from a second base station a second signal over the second range of frequencies, wherein the first signal has a first power level at the second base station, the second signal is transmitted at a second power level, and a difference between the first power level and the second power level is between zero and approximately 5 dBm.

16. The method of claim 15, wherein the portion of the second range of frequencies that overlaps with the first range of frequencies is a greater of (i) approximately ½

the first range of frequencies or (ii) approximately ½

the second range of frequencies.

17. The method of claim 15, wherein the portion of the second range of frequencies that overlaps with the first range of frequencies is defined by an offset between a first center frequency of the first spread spectrum channel and a second center frequency of the second spread spectrum channel, the offset being a greater of (i) approximately ½

the first range of frequencies or (ii) approximately ½

the second range of frequencies.

18. The method of claim 15, wherein the first range of frequencies is approximately 1.25 MHz, the second range of frequencies is approximately 1.25 MHz, and the portion of the second range of frequencies that overlaps with the first range of frequencies is approximately 0.625 MHz.

19. The method of claim 15, wherein the first spread spectrum channel and the second spread spectrum channel are CDMA channels.

20. The method of claim 15, wherein the first base station is in a public wireless network and the second base station is in a private wireless network.

21. A method of providing wireless network service, the method comprising:

establishing a first spread spectrum channel defined by a first range of frequencies;

establishing a second spread spectrum channel defined by a second range of frequencies, wherein the first range of frequencies overlaps with a portion of the second range of frequencies and the portion of the second range of frequencies that overlaps with the first range of frequencies is approximately half of the second range of frequencies;

transmitting from a first base station a first signal over the first range of frequencies; and

transmitting from a second base station a second signal over the second range of frequencies, wherein the first signal has a first power level at the second base station, the second signal is transmitted at a second power level, and a difference between the first power level and the second power level is between zero and approximately 5 dBm.

22. The method of claim 21, wherein the first range of frequencies has a first center frequency, the second range of frequencies has a second center frequency, and the first center frequency is offset from the second center frequency by approximately half of the second range of frequencies.

23. The method of claim 21, wherein the first range of frequencies is approximately 1.25 MHz, the second range of frequencies is approximately 1.25 MHz, and the portion of the second range of frequencies that overlaps with the first range of frequencies is approximately 0.625 MHz.

24. The method of claim 21, wherein the first spread spectrum channel and the second spread spectrum channel are CDMA channels.

25. The method of claim 21, wherein the first base station is in a public wireless network and the second base station is in a private wireless network.