Spread spectrum microwave overlay with notch filter

• US 6,407,989 B2
• Filed: 05/01/2001
• Issued: 06/18/2002
• Est. Priority Date: 01/21/1994
• Status: Expired due to Fees

• Current Assignee: Interdigital Technology Corporation (InterDigital, Inc.)
• Original Assignee: Interdigital Technology Corporation (InterDigital, Inc.)
• Inventors: Schilling, Donald L.
• Primary Examiner(s): CANGIALOSI, SALVATORE A
• Application Number:
  US09/846,068
• Publication Number:
  US 20010019547A1
• Time in Patent Office: 413 Days
• Field of Search: 370/320, 370/335, 370/342, 370/441, 370/321, 375/141
• US Class Current: 370/335
• CPC Class Codes: H04B 1/71 the interference being narrowband interference
• CPC Class Codes: H04W 52/343 taking into account loading or congestion level
• CPC Class Codes: H04W 52/346 distributing total power among users or channels

Abstract

A base station is in a spread spectrum code division multiple access (CDMA) communication system which co-exists with a microwave system. The microwave system selectively utilizes various microwave frequencies within a selected range of frequencies. The base station generates a plurality of spread spectrum CDMA data signals using pseudo random chip code sequences. The spread data signals encompass the selected range. The base station notch filters the spread data signals at microwave frequencies within the selected range used by the microwave system. The notch filtered spread data signals are transmitted to personal communication network units.

Claims

1. A base station for use in a spread spectrum code division multiple access (CDMA) communication system which co-exists with a microwave system, the microwave system selectively utilizing various microwave frequencies within a selected range of frequencies, the base station comprising:

means for generating a plurality of spread spectrum CDMA data signals using pseudo random chip code sequences, the spread data signals encompassing the selected range;

means for notch filtering the spread data signals at microwave frequencies within the selected range used by the microwave system; and

means for transmitting the notch filtered spread data signals to personal communication network units.

2. The base station of claim 1 further comprising means for determining microwave frequencies currently used by the microwave system that have a spectrum overlapping a spectrum of the spread data signal;

wherein the notch filtering is at the determined microwave frequencies.

3. The base station of claim 2 further comprising means for detecting a microwave power associated with the overlapping frequencies;

wherein the determining of the overlapping microwave frequencies is based on in part the detected microwave power.

4. The base station of claim 2 wherein each of the overlapping frequencies has an associated bandwidth, the unit further comprising:

means for determining the bandwidth for each of the overlapping frequencies;

wherein the notch filtering filters a bandwidth at each of the overlapping frequencies based on in part that frequency'"'"'s determined bandwidth.

5. The base station of claim 1 further comprising:

means for receiving a plurality of unit spread spectrum CDMA data signals and recovering data from the unit data signals;

wherein the unit data signals being notch filtered at the microwave frequencies within the selected range.

6. The base station of claim 5 further comprising:

means for notch filtering the received unit data signals at the microwave frequencies within the selected range prior to the recovering of data.

7. The base station of claim 6 further comprising means for determining microwave frequencies currently used by the microwave system that have a spectrum overlapping a spectrum of the spread data signals and received unit CDMA data signals;

wherein the notch filtering of the spread data signals is at the overlapping frequencies and the notch filtering of the received unit data signals is at the overlapping frequencies.

8. The base station of claim 7 further comprising means for detecting a microwave power associated with the overlapping frequencies wherein the determining of the overlapping microwave frequencies is based on in part the detected microwave power.

9. The base station of claim 7 wherein each of the overlapping frequencies has an associated bandwidth, the unit further comprising:

means for determining the bandwidth for each of the overlapping frequencies;

wherein the notch filtering of the spread data signal and the base data signal filters a bandwidth of each of the overlapping frequencies based on in part that frequency'"'"'s determined bandwidth.

10. A base station for use in a spread spectrum code division multiple access (CDMA) communication system which co-exists with a microwave system, the microwave frequencies within a selected range of frequencies, the base station comprising:

a plurality of mixers for mixing data signals with pseudo random chip code sequences to generate a plurality of spread spectrum CDMA data signals, the spread data signals encompassing the selected range of microwave frequencies;

a plurality of adaptive notch filters for notch filtering the spread data signals at microwave frequencies within the selected range used by the microwave system; and

an antenna for transmitting to personal communication network units the combined signal.

11. The base station of claim 10 further comprising a sensor detecting a microwave power associated with the microwave frequencies that have a spectrum overlapping a spectrum of the spread data signal, the detected microwave power used to determine the overlapping microwave frequencies;

wherein the adaptive notch filtering is at the determined microwave frequencies.

12. The base station of claim 10 further comprising a controller operatively coupled to the adjustable notch filters for controlling the adjustable notch filters to filter at the microwave frequencies used by the microwave system.

13. The base station of claim 10 further comprising a plurality of local oscillators for modulating the notch filtered spread data signals to radio frequency.

14. The base station of claim 10 wherein the antenna receives a plurality of unit spread spectrum CDMA data signals;

wherein the unit data signals being notch filtered at the microwave frequencies within the selected range.

15. The base station of claim 14 further comprising:

a plurality of despreaders for despreading the unit data signals;

a plurality of bandpass filters for filtering the despread unit data signals; and

a plurality of detectors for detecting data within the despread unit filtered data signals.

18. The base station of claim 10 further comprising a sensor detecting a microwave power associated with the microwave frequencies that have a spectrum overlapping a spectrum of the spread data signal, the detected microwave power used to determine the overlapping microwave frequencies;

wherein the adaptive notch filtering results in the spread RF data signals being filtered at the determined microwave frequencies.

19. The base station of claim 10 further comprising a controller operatively coupled to the adjustable notch filters for controlling the adjustable notch filters.

20. The base station of claim 10 wherein the antenna receives a plurality of unit spread spectrum CDMA data signals;

wherein the unit data signals being notch filtered at the microwave frequencies within the selected range.

16. A base station for use in a spread spectrum code division multiple access (CDMA) communication system which co-exits with a microwave system, the microwave frequencies within a selected range of frequencies, the base station comprising:

a first plurality of mixers for mixing data signals with pseudo random chip code sequences to generate a plurality of spread spectrum CDMA data signals;

a second plurality of mixers for mixing the spread data signals with an intermediate frequency (IF) signal as a plurality of IF spread data signals;

a plurality of adaptive notch filters for notch filtering the IF data signals;

a third plurality of mixers for mixing the filtered IF data signals with a radio frequency (RF) signal as spread RF data signals;

wherein the spread RF data signals are effectively notch filtered at microwave frequencies within the selected ranges; and

an antenna for transmitting to personal communication network units the spread RF data signals.

17. The base station of claim 16 further comprising a combiner for combining the spread RF data signals prior to transmission.