Mirror translation loop transmitter architecture

• US 20040017858A1
• Filed: 07/29/2002
• Published: 01/29/2004
• Est. Priority Date: 07/29/2002
• Status: Active Grant

• Current Assignee: Skyworks Solutions Incorporated
• Original Assignee: Conexant Systems Incorporated (Synaptics Incorporated)
• Inventors: Domino, William J., Rozenblit, Dmitriy, Damgaard, Morten
• Granted Patent: US 7,082,169 B2
• Time in Patent Office: Days
• US Class Current: 375/295
• CPC Class Codes: H03C 3/0966 modulating the reference clock
• CPC Class Codes: H03C 3/0983 containing in the loop a mixer other than for phase detection
• CPC Class Codes: H03C 5/00 Amplitude modulation and angle modulation produced simultaneously or at will by the same modulating signal H03C7/00 takes precedence
• CPC Class Codes: H04L 27/0002 analog front ends; means for connecting modulators, demodulators or transceivers to a transmission line duplex arrangements H04L5/143
• CPC Class Codes: H04L 27/2017 in which the phase changes are non-linear, e.g. generalized and Gaussian minimum shift keying, tamed frequency modulation H04L27/201 takes precedence

Abstract

A mirror translation loop upconverter that is capable of upconverting both constant envelope and non-constant envelope modulation formats is disclosed. Embodiments of the invention provide the ability to upconvert a transmit signal that includes only a phase-modulated component, only an amplitude-modulated component, or both a phase-modulated component and an amplitude-modulated component. If the transmit signal includes both a phase-modulated signal component and an amplitude-modulated signal component, the phase-modulated signal component and the amplitude-modulated signal component are supplied to a pair of phase shifters. The phase shifters alter the phase of the phase-modulated signal by an amount related to the amplitude of the amplitude-modulated signal. The phase shifters oppositely alter the phase of the phase-modulated signal, and therefore supply complementary phase versions of the phase-modulated signal. The phase-altered phase-modulated signals from the phase shifters are then supplied to a pair of translation loops. The translation loops are arranged in mirror architecture so that each translation loop receives the phase-altered phase-modulated signals. Each translation loop upconverts the signals and supplies a vector. The vectors supplied by the two translation loops are constant in magnitude, and have complementary phase. The two vectors are added together to provide a signal to a power amplifier. The signal represents both the phase and amplitude information to be transmitted.

Claims

1. A method for signal up-conversion, comprising:

providing a first modulated signal and a second modulated signal to a first phase shifter;

providing the first modulated signal and the second modulated signal to a second phase shifter;

altering the phase of the first modulated signal by an amount related to the magnitude of the second modulated signal so that the first phase shifter and the second phase shifter each provide a phase-altered version of the first modulated signal;

supplying the output of the first phase shifter and the second phase shifter to a pair of translation loops;

upconverting the phase-altered version of the first modulated signal in a first of the pair of translation loops;

upconverting the phase-altered version of the first modulated signal in a second of the pair of translation loops;

combining the outputs of the first and second translation loops where the combined signal represents the first and second modulated signals.

2. The method of claim 1, wherein the first modulated signal is phase-modulated and the second modulated signal is amplitude-modulated.

3. The method of claim 1, wherein the first phase shifter and the second phase shifter are implemented as an in-phase (I) and quadrature (Q) modulator.

4. The method of claim 1, wherein the phase-altered version of the first modulated signal supplied by the first phase shifter and the second phase shifter are altered by the same amount of phase, but each with opposite sign.

5. The method of claim 1, wherein the outputs of the first and second translation loops are constant amplitude vectors and wherein the combining step combines the constant amplitude vectors to generate the combined signal having a phase defined by the phase of the constant amplitude vectors and an amplitude defined by the combined amplitude of the constant amplitude vectors.

6. The method of claim 1, wherein the first and second modulated signals are intermediate frequency signals.

7. The method of claim 1, wherein the first and second modulated signals are baseband signals.

8. A translation loop upconverter, comprising:

a first phase shifter configured to receive first and second modulated signals;

a second phase shifter configured to receive the first and second modulated signals, the first and second phase shifters configured to amplify the first modulated signal and configured to alter the phase of the first modulated signal by an amount related to the magnitude of the second modulated signal, where the output of the first and second phase shifters comprises a phase-altered version of the first modulated signal;

a first translation loop having a first phase locked loop and configured to receive the output of the first phase shifter, and supply an output signal at a particular phase and amplitude;

a second translation loop having a second phase locked loop and configured to receive the output of the second phase shifter, and supply an output signal at a particular phase and amplitude; and

an adder configured to add the outputs of the first translation loop and the second translation loop, where the output of the adder is a combined signal representing the phase and amplitude of the first and second modulated signals.

9. The system of claim 8, wherein the first phase shifter and the second phase shifter further comprise an in-phase (I) and quadrature (Q) modulator.

10. The system of claim 8, wherein the first and second modulated signals are intermediate frequency signals.

11. The system of claim 8, wherein the first and second modulated signals are baseband signals.

12. The system of claim 8, wherein the first modulated signal is a phase-modulated signal.

13. The system of claim 8, wherein the second modulated signal is an amplitude-modulated signal.

14. The system of claim 8, wherein the outputs of the first and second translation loops are constant amplitude vectors and wherein the combining step combines the constant amplitude vectors to generate the combined signal having a phase defined by the phase of the constant amplitude vectors and an amplitude defined by the combined amplitude of the constant amplitude vectors.

15. The system of claim 8, wherein the phase-altered version of the first modulated signal supplied by the first phase shifter and the second phase shifter are opposite in phase.

16. A method for transmit signal upconversion in a portable telecommunications device, comprising:

providing a first combined signal and a second combined signal to respective first and second translation loops, the first combined signal including a first modulated signal that is altered in phase by an amount related to the magnitude of a second modulated signal, the second combined signal including the first modulated signal that is altered in phase by an amount related to the magnitude of a second modulated signal, the second combined signal being altered by the same amount of phase as the first combined signal, but opposite in sign from the first combined signal;

upconverting the first combined signal and the second combined signal; and

adding the upconverted first and second combined signals resulting in a third combined upconverted signal that includes the information in the first modulated signal and the second modulated signal.

17. The method of claim 16, where the first modulated signal is phase-modulated and the second modulated signal is amplitude-modulated.

18. The method of claim 17, further comprising:

supplying the phase-modulated signal and an amplitude-modulated signal to a first phase shifter; and

supplying the phase-modulated signal and the amplitude-modulated signal to a second phase shifter.

19. The method of claim 18, wherein the first phase shifter and the second phase shifter further comprise an in-phase (I) and quadrature (Q) modulator.

20. The method of claim 18, wherein the first modulated signal and the second modulated signal are intermediate frequency signals.

21. The method of claim 18, wherein the first modulated signal and the second modulated signal are baseband signals.

22. The method of claim 16, wherein the upconverted first and second combined signals are constant amplitude vectors and wherein the adding step combines the constant amplitude vectors to generate the third combined upconverted signal having a phase defined by the phase of the constant amplitude vectors and an amplitude defined by the combined amplitude of the constant amplitude vectors.

23. A system for transmit signal upconversion in a portable telecommunications device, comprising:

a pair of translation loops each translation loop configured to receive a combined signal including a first modulated signal that is altered in phase by an amount related to the magnitude of a second modulated signal;

where each of the translation loops upconvert the combined signal; and

an adder configured to add the output of each of the translation loops resulting in a combined upconverted signal.

24. The system of claim 23, where the first modulated signal is phase-modulated and the second modulated signal is amplitude-modulated.

25. The system of claim 24, further comprising:

a first phase shifter configured to receive the phase-modulated signal and the amplitude-modulated signal, and supply the phase-modulated signal altered in phase by an amount related to the magnitude of the second modulated signal to a first of the translation loops; and

a second phase shifter configured to receive the phase-modulated signal and the amplitude-modulated signal, and supply the phase-modulated signal altered in phase by an amount related to the magnitude of the second modulated signal to a second of the translation loops, where the first phase shifter and the second phase shifter alter the phase-modulated signal by the same amount, but with opposite sign.

26. The system of claim 23, wherein the first phase shifter and the second phase shifter further comprise an in-phase (I) and quadrature (Q) modulator.

27. The system of claim 23, wherein the outputs of each of the translation loops are constant amplitude vectors and wherein the adder combines the constant amplitude vectors to generate the combined upconverted signal having a phase defined by the phase of the constant amplitude vectors and an amplitude defined by the combined amplitude of the constant amplitude vectors.

28. A system for signal up-conversion, comprising:

means for providing a first modulated signal and a second modulated signal to a first phase shifter;

means for providing the first modulated signal and the second modulated signal to a second phase shifter;

means for altering the phase of the first modulated signal by an amount related to the magnitude of the second modulated signal so that the first phase shifter and the second phase shifter each provide a phase-altered version of the first modulated signal;

means for supplying the outputs of the first phase shifter and the second phase shifter to a pair of translation loops;

means for upconverting the phase-altered version of the first modulated signal in a first of the pair of translation loops;

means for upconverting the phase-altered version of the first modulated signal in a second of the pair of translation loops;

means for combining the outputs of the first and second translation loops where the combined signal represents the first and second modulated signals.

29. A system for transmit signal upconversion in a portable telecommunications device, comprising:

a pair of translation loops, each translation loop configured to receive one of two complementary phase-modulated signals;

where each of the translation loops upconverts a selected one of the two complementary phase-modulated signals; and

an adder configured to add the outputs of each of the translation loops resulting in a combined upconverted signal.