Hybrid multi-band receiver

• US 8,576,768 B2
• Filed: 04/16/2009
• Issued: 11/05/2013
• Est. Priority Date: 04/16/2009
• Status: Expired due to Fees

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Zhao, Liang, Brockenbrough, Roger, Kohlmann, Michael, Conroy, Cormac S., Savla, Anup
• Primary Examiner(s): LI, GUANG W
• Application Number:
  US12/425,285
• Publication Number:
  US 20100265875A1
• Time in Patent Office: 1,664 Days
• Field of Search: 370/316
• US Class Current: 370/316
• CPC Class Codes: H04B 1/0007 wherein the AD/DA conversion occurs at radiofrequency or intermediate frequency stage
• CPC Class Codes: H04B 1/005 adapting radio receivers, transmitters andtransceivers for operation on two or more bands, i.e. frequency ranges
• CPC Class Codes: H04B 1/0064 with separate antennas for the more than one band H04B1/0053 takes precedence
• CPC Class Codes: H04B 1/0075 using different intermediate frequencied for the different bands

Abstract

The subject matter disclosed herein relates to a system and method for processing wireless signals received from one or more communications systems. In a particular implementation, one or more signals received from one or more communication systems such as a GNSS may be processed in two or more separate wireless signal receiver paths and combined in baseband to share one analog-to-digital converter.

Claims

1. A method, comprising:

receiving two or more wireless signals at a receiver at two or more receiver paths;

downconverting the two or more received wireless signals using two or more separate complex mixers in the two or more receiver paths to generate at least in-phase and quadrature intermediate frequency signals based, at least in part, on two or more oscillating signals having individually selectable frequencies received from one or more local oscillators to enable oscillating signals at different frequencies to be applied to different ones of said separate complex mixers generating said in-phase and quadrature intermediate frequency signals;

combining the two or more in-phase and quadrature intermediate frequency signals to generate a combined signal comprising an in-phase component and a quadrature component;

converting the combined signal to a digital signal using a single analog-to-digital converter, the digital signal comprising an in-phase component and a quadrature component; and

wherein said two or more receiver paths comprise two or more low noise amplifiers, and wherein said in-phase and quadrature intermediate frequency signals are spectrally shifted to different intermediate frequencies by said separate complex mixers.

2. The method of claim 1, wherein said two or more received wireless signals comprise a single wireless signal transmitted from a first satellite positioning system (SPS) and received at two or more antennae associated with said two or more receiver paths.

3. The method of claim 2, wherein said two or more oscillating signals have approximately the same frequency and wherein a first of said two or more oscillating signals is approximately 180°

out of phase with a second of said two or more oscillating signals.

4. The method of claim 3, wherein said downconverting further comprises:

mixing a first wireless signal received at a first of said two or more antennae with the first oscillator signal; and

mixing a second wireless signal received at a second of said two or more antennae the second oscillator signal.

5. The method of claim 1, wherein said two or more received wireless signals comprise a first wireless signal transmitted from a first global navigation satellite system (GNSS) and a second wireless signal also transmitted from the first GNSS.

6. The method of claim 5, wherein said two or more oscillating signals are selected to have differing frequencies.

7. The method of claim 1, wherein said two or more received wireless signals comprise a first wireless signal transmitted from a first global navigation satellite system (GNSS) and a second wireless signal transmitted from a second GNSS.

8. The method of claim 7, wherein said two or more oscillating signals are selected to have differing frequencies.

9. The method of claim 7, wherein the first wireless signal is transmitted from a Glonass GNSS, and wherein the second wireless signal is transmitted from an satellite positioning system comprising a GPS GNSS and/or a Galileo GNSS.

10. The method of claim 1, wherein said two or more receiver paths receive said two or more wireless signals through two or more antennae, and wherein said two or more receiver paths comprise two or more baseband filters.

11. The method of claim 1, further comprising filtering the combined signal using a combined signal baseband filter, the analog-to-digital converter to receive the combined signal from the combined signal baseband filter.

12. The method of claim 1, further comprising separating the digital signal into a plurality of in-phase components and a plurality of quadrature components using a complex down-conversion operation.

13. A mobile station, comprising:

a receiver comprising two or more radio receiver paths to receive two or more wireless signals;

two or more separate complex mixers in the two or more receiver paths to downconvert the two or more received wireless signals to generate at least in-phase and quadrature intermediate frequency signals based, at least in part, on two or more oscillating signals having individually selectable frequencies received from one or more local oscillators to enable oscillating signals at different frequencies to be applied to different ones of said separate complex mixers generating said in-phase and quadrature intermediate frequency signals;

a combiner to combine the two or more in-phase and quadrature intermediate frequency signals to generate a combined signal comprising an in-phase component and a quadrature component;

an analog-to-digital converter to convert the combined signal to a digital signal using a single analog-to-digital converter, the digital signal comprising an in-phase component and a quadrature component; and

wherein said two or more receiver paths comprise two or more low noise amplifiers, and wherein said in-phase and quadrature intermediate frequency signals are spectrally shifted to different intermediate frequencies by said separate complex mixers.

14. The mobile station of claim 13, wherein said two or more wireless signals comprise a single wireless signal transmitted from a first satellite positioning system (SPS) and received at two or more antennae associated with said two or more receiver paths.

15. The mobile station of claim 14, wherein said two or more oscillating signals have approximately the same frequency and wherein a first of said two or more oscillating signals is approximately 180°

out of phase with a second of said two or more oscillating signals.

16. The mobile station of claim 15, said two or more complex mixers to downconvert the two or more wireless signals by mixing a first wireless signal received at a first of said two or more antennae with the first oscillator signal and mixing a second wireless signal received at a second of said two or more antennae the second oscillator signal.

17. The mobile station of claim 13, wherein said two or more wireless signals comprise a first wireless signal transmitted from a first global navigation satellite system (GNSS) and a second wireless signal also transmitted from the first GNSS.

18. The mobile station of claim 17, wherein said two or more oscillating signals are selected to have differing frequencies.

19. The mobile station of claim 13, wherein said two or more wireless signals comprise a first wireless signal transmitted from a first global navigation satellite system (GNSS) and a second wireless signal transmitted from a second GNSS.

20. The mobile station of claim 19, wherein said two or more oscillating signals are selected to have differing frequencies.

21. The mobile station of claim 19, wherein the first wireless signal is transmitted from a Glonass GNSS, and wherein the second wireless signal is transmitted from a satellite positioning system comprising a GPS GNSS and/or a Galileo GNSS.

22. The mobile station of claim 13, further comprising two or more antennae associated with said two or more receiver paths, said two or more receiver paths to receive said two or more wireless signals through said two or more antennae, and wherein said two or more receiver paths comprise two or more baseband filters.

23. The mobile station of claim 13, wherein said two or more receiver paths comprise two or more low noise amplifiers.

24. The mobile station of claim 13, further comprising a combined signal baseband filter to filter the combined signal, the analog-to-digital converter to receive the combined signal from the combined signal baseband filter.

25. The mobile station of claim 13, further comprising a complex down-converter coupled to the analog-to-digital converter, the complex down-converter to separate the digital signal into a plurality of in-phase components and a plurality of quadrature components using a complex down-conversion operation.

26. An apparatus, comprising:

two or more separate means for receiving two or more wireless signals;

two or more separate means for downconverting the two or more received wireless signals to generate at least in-phase and quadrature phased intermediate frequency signals based, at least in part, on two or more oscillating signals having individually selectable frequencies received from one or more local oscillators to enable oscillating signals at different frequencies to be applied to different ones of said separate complex mixers generating said in-phase and quadrature intermediate frequency signals;

means for combining the two or more in-phase and quadrature intermediate frequency signals to generate a combined signal comprising an in-phase component and a quadrature component;

means for converting the combined signal to a digital signal using a single analog-to-digital converter, the digital signal comprising an in-phase component and a quadrature component; and

wherein said two or more receiver paths comprise two or more low noise amplifiers, and wherein said in-phase and quadrature intermediate frequency signals are spectrally shifted to different intermediate frequencies by said separate complex mixers.

27. The apparatus of claim 26, wherein said two or more wireless signals comprise a single wireless signal transmitted from a first satellite positioning system (SPS) and received at two or more antennae associated with said two or more means for receiving.

28. The apparatus of claim 27, wherein said two or more oscillating signals have approximately the same frequency and wherein a first of said two or more oscillating signals is approximately 180°

out of phase with a second of said two or more oscillating signals.

29. The apparatus of claim 28, wherein said two or more means for downconverting further comprises:

means for mixing a first wireless signal received at a first of said two or more antennae with the first oscillator signal; and

means for mixing a second wireless signal received at a second of said two or more antennae the second oscillator signal.

30. The apparatus of claim 26, wherein said two or more wireless signals comprise a first wireless signal transmitted from a first global navigation satellite system (GNSS) and a second wireless signal also transmitted from the first GNSS.

31. The apparatus of claim 30, wherein said two or more oscillating signals are selected to have differing frequencies.

32. The apparatus of claim 26, wherein said two or more wireless signals comprise a first wireless signal transmitted from a first global navigation satellite system (GNSS) and a second wireless signal transmitted from a second GNSS.

33. The apparatus of claim 32, wherein said two or more oscillating signals are selected to have differing frequencies.

34. The apparatus of claim 32, wherein the first wireless signal is transmitted from a Glonass GNSS, and wherein the second wireless signal is transmitted from an satellite positioning system comprising a GPS GNSS and/or a Galileo GNSS.

35. The apparatus of claim 26, wherein said two or more means for receiving receive said two or more wireless signals through two or more antennae, and wherein said two or more means for receiving comprise two or more means for filtering.

36. The apparatus of claim 26, wherein said two or more means for receiving comprise two or more means for low noise amplification of the two or more wireless signals.

37. The apparatus of claim 26, further comprising means for filtering the combined signal, the means for converting the combined signal to a digital signal to receive the combined signal from the means for filtering the combined signal.

38. The apparatus of claim 26, further comprising means for separating the digital signal into a plurality of in-phase components and a plurality of quadrature components.