Method and Apparatus for Transmitting and Receiving High Speed Data Using Code Division Multiple Access Channels

• US 20090252141A1
• Filed: 05/26/2009
• Published: 10/08/2009
• Est. Priority Date: 07/10/1998
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Tiedemann, Edward G. JR.
• Granted Patent: US 8,345,728 B2
• Time in Patent Office: Days
• US Class Current: 370/342
• CPC Class Codes: H04B 1/692 Hybrid techniques using combinations of two or more spread spectrum techniques
• CPC Class Codes: H04B 1/707 using direct sequence modulation
• CPC Class Codes: H04B 1/7087 Carrier synchronisation aspects
• CPC Class Codes: H04B 1/713 using frequency hopping
• CPC Class Codes: H04B 1/7136 Arrangements for generation of hop frequencies, e.g. using a bank of frequency sources, using continuous tuning or using a transform
• CPC Class Codes: H04B 2201/70703 using multiple or variable rates
• CPC Class Codes: H04B 7/2628 using code-division multiple access [CDMA] or spread spectrum multiple access [SSMA] H04B7/2618 takes precedence

Abstract

The present invention describes a spread spectrum communication system wherein the frequency of carriers and the code channels of the carriers or both for transmission to a given remote station user vary in time. This provides for a direct sequence spectrum communications system which changes frequency or code channel according to a predetermined pattern. The code channels and frequencies can be determined in accordance with a deterministic function or based upon a subset of the data to be transmitted. A receiver structure is also described for receiving the same.

Claims

1. A method comprising:

modulating data;

scrambling a subset of information bits of the modulated data;

selecting a frequency in accordance with the modulated, scrambled subset of information bits; and

upconverting the modulated data using the selected frequency.

2. The method of claim 1, further comprising:

scrambling another subset of information bits of the data; and

selecting a code channel in accordance with the another subset of information bits, wherein the data is modulated using the selected code channel.

3. The method of claim 1, further comprising generating a selection signal in accordance with the modulated, scrambled subset of information bits, wherein the frequency is selected in accordance with the selection signal.

4. The method of claim 1, wherein the frequency is selected in accordance with a pseudorandom sequence.

5. The method of claim 1, wherein the upconverting the modulated data comprises using a variable frequency synthesizer to generate the selected frequency.

6. The method of claim 1, wherein the data is modulated using a Walsh code.

7. The method of claim 2, wherein the code channel is selected in accordance with a pseudorandom sequence.

8. The method of claim 5, wherein the variable frequency synthesizer comprises a direct digital synthesizer.

9. An apparatus, comprising:

means for modulating data to be transmitted;

means for scrambling a subset of information bits of the modulated data;

means for selecting a frequency in accordance with the scrambled subset of information bits; and

means for upconverting the modulated data using the selected frequency.

10. The apparatus of claim 9, further comprising means for selecting a code channel to modulate the data, wherein the data is modulated using the selected code channel.

11. The apparatus of claim 9, further comprising:

means for scrambling another subset of information bits of the data; and

means for selecting a code channel in accordance with the another subset of information bits, wherein the data is modulated using the selected code channel.

12. The apparatus of claim 9, further comprising means for generating a selection signal in accordance with the modulated, scrambled subset of information bits, wherein the frequency is selected in accordance with the selection signal.

13. The apparatus of claim 9, wherein the frequency is selected in accordance with a pseudorandom sequence.

14. The apparatus of claim 9, wherein the means for upconverting the modulated data comprises using a means for variable frequency synthesizing to generate the selected frequency.

15. The apparatus of claim 9, wherein the data is modulated using a Walsh code.

16. The apparatus of claim 11, wherein the code channel is selected in accordance with a pseudorandom sequence.

17. The apparatus of claim 14, wherein the means for variable frequency synthesizing comprises a direct digital synthesizer.

18. A computer program product, comprising:

computer-readable medium comprising;

code for causing a computer to;

modulate the data;

scramble a subset of information bits of the modulated data;

select a frequency in accordance with the scrambled subset of information bits; and

upconvert the modulated data using the selected frequency.

19. The computer program product of claim 18, said code further comprising:

scrambling another subset of information bits of the data; and

selecting a code channel in accordance with the another subset of information bits, wherein the data is modulated using the selected code channel.

20. The computer program product of claim 18, said code further comprising generating a selection signal in accordance with the modulated, scrambled subset of information bits, wherein the frequency is selected in accordance with the selection signal.

21. The computer program product of claim 18, wherein the frequency is selected in accordance with a pseudorandom sequence.

22. The computer program product of claim 18, wherein the upconverting the modulated data comprises using a variable frequency synthesizer to generate the selected frequency.

23. The computer program product of claim 18, wherein the data is modulated using a Walsh code.

24. The computer program product of claim 19, wherein the code channel is selected in accordance with a pseudorandom sequence.

25. The computer program product of claim 22, wherein the variable frequency synthesizer comprises a direct digital synthesizer.

26. An apparatus comprising:

a modulator adapted to modulate data;

a scrambler adapted to scramble a subset of information bits of the modulated data;

a switch adapted to select a frequency in accordance with the modulated, scrambled subset of information bits; and

an upconverter adapted to upconvert the modulated data using the selected frequency.

27. The apparatus of claim 26, further comprising:

a processor further adapted to select a code channel in accordance with the another subset of information bits, wherein the data is modulated using the selected code channel and wherein said scrambler is adapted to scramble another subset of information bits of the data.

28. The apparatus of claim 26, further comprising a processor to generate a selection signal in accordance with the modulated, scrambled subset of information bits, wherein the frequency is selected in accordance with the selection signal.

29. The apparatus of claim 26, wherein the frequency is selected in accordance with a pseudorandom sequence.

30. The apparatus of claim 26, wherein the upconverting the modulated data comprises using a variable frequency synthesizer to generate the selected frequency.

31. The apparatus of claim 26, wherein the data is modulated using a Walsh code.

32. The apparatus of claim 27, wherein the selection signal is generated in accordance with a pseudorandom sequence.

33. The apparatus of claim 30, wherein the variable frequency synthesizer comprises a direct digital synthesizer.