System and method providing signal combining to support multimode communication

• US 8,416,879 B2
• Filed: 03/15/2006
• Issued: 04/09/2013
• Est. Priority Date: 12/01/2005
• Status: Active Grant

• Current Assignee: Avago Technologies International Sales Pte Limited (Broadcom, Inc.)
• Original Assignee: Broadcom Corporation (Broadcom, Inc.)
• Inventors: Rofougaran, Ahmadreza, Behzad, Arya
• Primary Examiner(s): Yu, Lihong
• Application Number:
  US11/376,643
• Publication Number:
  US 20070127590A1
• Time in Patent Office: 2,582 Days
• Field of Search: 375/285, 375/304, 375/299
• US Class Current: 375/285
• CPC Class Codes: H04B 1/0075 using different intermediate frequencied for the different bands
• CPC Class Codes: H04B 1/04 Circuits

Abstract

A system and method providing signal combining to support multimode communication. Various aspects of the present invention may provide a first input adapted to receive a first baseband signal corresponding to a first communication protocol. A second input may be provided, which is adapted to receive a second baseband signal corresponding to a second communication protocol. A spectral placement module may, for example, be adapted to spectrally shift the first baseband signal. For example, the spectral placement module may be adapted to spectrally shift the first baseband signal to one or more frequency bands substantially distinct from one or more frequency bands associated with the second baseband signal. The spectrally shifted first baseband signal and the second baseband signal, which may also be spectrally shifted, may then be combined to form a composite signal.

Claims

1. A multimode communication system, comprising:

at least a first module comprising circuitry, the first module being operable to, at least;

generate a first baseband wireless signal corresponding to a first wireless communication protocol; and

generate a second baseband wireless signal corresponding to a second wireless communication protocol different from the first wireless communication protocol, the second baseband wireless signal characterized by a baseband frequency bandwidth of the second baseband wireless signal; and

at least a second module comprising circuitry, the second module being operable to, at least;

receive the first baseband wireless signal;

receive the second baseband wireless signal;

spectrally shift an in-phase (I) component of the received first baseband wireless signal to a frequency space beyond the baseband frequency bandwidth, the spectral shift including mixing the I component and quadrature phase (Q) component of the first baseband wireless signal with respective I and Q components of a mixing signal;

spectrally shift the Q component of the received first baseband wireless signal to the same frequency space beyond the baseband frequency bandwidth, the spectral shift including mixing the I and Q components of the first baseband wireless signal with respective Q and I components of the mixing signal; and

generate a composite wireless signal comprising, at an instant in time, an I composite component and a Q composite component, each composite component including a first component based on the spectrally-shifted first baseband wireless signal, and a second component based on the second baseband wireless signal that has not been spectrally-shifted.

2. The multimode communication system of claim 1, wherein the second module is operable to generate the composite signal by, at least in part, combining the first component and the second component at radio frequency (RF) frequencies.

3. The multimode communication system of claim 1, wherein the second module is operable to generate the composite signal by, at least in part, operating to combine the spectrally-shifted I component of the first baseband wireless signal with an I component of the second baseband wireless signal and operating to combine the spectrally-shifted Q component of the first baseband wireless signal with a Q component of the second baseband wireless signal.

4. The multimode communication system of claim 1, wherein the second module is operable to spectrally shift the first baseband wireless signal to the frequency space beyond the baseband frequency bandwidth by, at least in part, spectrally shifting the first baseband wireless signal to a plurality of frequency bands not associated with the second baseband wireless signal.

5. The multimode communication system of claim 1, wherein the second module is operable to spectrally shift the received first baseband wireless signal to the frequency space beyond the baseband frequency bandwidth by, at least in part, frequency hopping the first baseband wireless signal to a plurality of frequency bands substantially distinct from one or more frequency bands associated with the second baseband wireless signal, which is not frequency-hopped.

6. The multimode communication system of claim 1, wherein the second module is operable to reject an image associated with the spectrally-shifted I component of the first baseband wireless signal and reject an image associated with the spectrally-shifted Q component of the first baseband wireless signal.

7. The multimode communication system of claim 6, wherein the second module is operable to, prior to generating the composite signal, combine a first mixed component including the I component of the first baseband wireless signal and an I component of the mixing signal with a second mixed component including the Q component of the first baseband wireless signal with a Q component of the mixing signal to provide the spectrally-shifted I component of the first baseband wireless signal and combine a third mixed component including the Q component of the first baseband wireless signal and the I component of the mixing signal with a fourth mixed component including the I component of the first baseband wireless signal with the Q component of the mixing signal to provide the spectrally-shifted Q component of the first baseband wireless signal.

8. The multimode communication system of claim 6, wherein the second module is operable to upconvert the composite signal to a radio frequency (RF) frequency range and perform the image rejection on the upconverted composite signal.

9. The multimode communication system of claim 1, where the first baseband wireless signal, second baseband wireless signal and composite signal are digital signals.

10. The multimode communication system of claim 1, where the first baseband wireless signal, second baseband wireless signal and composite signal are analog signals.

11. The multimode communication system of claim 1, where the first wireless communication protocol is based on a Bluetooth standard, and the second wireless communication protocol is based on an IEEE 802.11 standard.

12. The multimode communication system of claim 1, where the composite signal comprises a baseband signal.

13. The multimode communication system of claim 1, where the composite signal comprises an intermediate frequency (IF) signal.

14. The multimode communication system of claim 1, where the composite signal comprises a radio frequency (RF) signal.

15. The multimode communication system of claim 1, wherein the at least a second module operates to upconvert the composite signal to a radio frequency (RF) signal that comprises the composite signal shifted to an RF frequency for transmission.

16. The multimode communication system of claim 1, where the first wireless communication protocol is associated with a first baseband frequency band and the second wireless communication protocol is associated with a second baseband frequency band different from the first baseband frequency band, and where the second baseband frequency band at least partially overlaps the first baseband frequency band.

17. The multimode communication system of claim 1, where the multimode communication system is a personal mobile communication device.

18. A method for communicating, the method comprising:

generating a first baseband wireless signal corresponding to a first wireless communication protocol;

generating a second baseband wireless signal corresponding to a second wireless communication protocol that is different from the first wireless communication protocol, the second baseband wireless signal characterized by a baseband frequency bandwidth of the second baseband wireless signal;

spectrally shifting an in-phase (I) component of the first baseband wireless signal to a frequency space beyond the baseband frequency bandwidth by mixing the in-phase (I) component and a quadrature (Q) component of the first baseband wireless signal with respective I and Q components of a mixing signal;

spectrally shifting an quadrature phase (Q) component of the first baseband wireless signal to a frequency space beyond the baseband frequency bandwidth by mixing the quadrature (Q) component and in-phase (I) component of the first baseband wireless signal with respective I and Q components of the mixing signal; and

generating a composite wireless signal comprising, at an instant in time, a first component based on the spectrally-shifted first baseband wireless signal and a second component based on the second baseband wireless signal where the first baseband wireless signal and the second baseband wireless signal are converted from digital signals to analog signals prior to generating the composite wireless signal.

19. The method of claim 18, wherein said generating a composite signal comprises combining the first component and the second component at radio frequencies (RF) frequencies.

20. The method of claim 18, wherein said generating a composite signal comprises generating the composite signal by, at least in part, combining the spectrally-shifted first baseband wireless signal and the second baseband wireless signal.

21. The method of claim 18, wherein said spectrally shifting the first baseband signal comprises spectrally shifting the first baseband wireless signal to a plurality of frequency bands not associated with the second baseband wireless signal.

22. The method of claim 18, wherein said spectrally shifting the first baseband wireless signal comprises frequency hopping the first baseband wireless signal to a plurality of frequency bands substantially distinct from one or more frequency bands associated with the second baseband wireless signal, which is not frequency-hopped.

23. The method of claim 18, comprising rejecting an image associated with the spectrally-shifted I component of the first baseband wireless signal and rejecting an image associated with the spectrally-shifted Q component of the first baseband wireless signal.

24. The method of claim 23, comprising, prior to generating the composite signal, performing image rejection on the I and Q components associated with the spectrally-shifted first baseband wireless signal and not on a signal associated with the second wireless baseband signal.

25. The method of claim 23, comprising upconverting the composite signal to a radio frequency (RF) frequency range and performing said image rejection on the upconverted composite signal.

26. The method of claim 18, wherein the first baseband wireless signal and the second baseband wireless signal are digital signals.

27. The method of claim 18, wherein the first baseband wireless signal is converted from a digital signal to an analog signal prior to spectrally shifting the first baseband wireless signal.

28. The method of claim 18, wherein the first wireless communication protocol is based on a Bluetooth standard, and the second wireless communication protocol is based on an IEEE 802.11 standard.

29. The method of claim 18, wherein the composite signal comprises a baseband signal.

30. The method of claim 18, wherein the composite signal comprises an intermediate frequency (IF) signal.

31. The method of claim 18, wherein the composite signal comprises a radio frequency (RF) signal.

32. The method of claim 18, comprising upconverting the composite signal to a radio frequency (RF) signal that comprises the composite signal shifted to an RF frequency for transmission.

33. The method of claim 18, wherein the first wireless communication protocol is associated with a first baseband frequency band and the second wireless communication protocol is associated with a second baseband frequency band different from the first baseband frequency band, where the second baseband frequency band at least partially overlaps the first baseband frequency band.

34. The method of claim 18, comprising performing the method in a personal mobile communication device.

35. Circuitry in a multimode communication system, wherein the circuitry is operable to, at least:

receive a first wireless signal associated with a first wireless communication protocol;

receive, by the spectral placement circuitry, a second wireless signal associated with a second wireless communication protocol different from the first wireless communication protocol, the received second wireless signal characterized by a frequency bandwidth of the second wireless signal;

spectrally shift, by the spectral placement circuitry, an in-phase (I) component of the received first wireless signal to a frequency space beyond the frequency bandwidth, the spectral shift including mixing the I component and quadrature phase (Q) component of the first wireless signal with corresponding I and Q components of a mixing signal;

spectrally shift, by the spectral placement circuitry, the Q component of the received first wireless signal to the same frequency space beyond the frequency bandwidth, the spectral shift including mixing the I and Q components of the first wireless signal with corresponding Q and I components of the mixing signal; and

generate, by signal combiner circuitry, a composite wireless signal comprising, at an instant in time, an I composite component and a Q composite component, each composite component including a first component based on the spectrally-shifted first baseband wireless signal, and a second component based on the second wireless signal.

36. The circuitry of claim 35, wherein the circuitry is operable to spectrally generate the composite signal by, at least in part, operating to combine the spectrally-shifted first wireless signal and the second wireless signal, which has not been spectrally shifted.