Systems and methods of RF power transmission, modulation, and amplification, including multiple input single output (MISO) amplifier embodiments comprising harmonic control circuitry
Methods and systems for vector combining power amplification are disclosed herein. In one embodiment, a plurality of signals are individually amplified, then summed to form a desired time-varying complex envelope signal. Phase and/or frequency characteristics of one or more of the signals are controlled to provide the desired phase, frequency, and/or amplitude characteristics of the desired time-varying complex envelope signal. In another embodiment, a time-varying complex envelope signal is decomposed into a plurality of constant envelope constituent signals. The constituent signals are amplified equally or substantially equally, and then summed to construct an amplified version of the original time-varying envelope signal. Embodiments also perform frequency up-conversion.
1. An apparatus for power transmission, modulation, and amplification, comprising:
a transfer function module;
modulation circuitry coupled to said transfer function module;
a power amplification stage coupled to said modulation circuitry; wherein said power amplification stage comprises a plurality of power amplifiers having outputs that are coupled to form an output of said apparatus; and
harmonic control circuitry; wherein said harmonic control circuitry comprises a plurality of harmonic control circuit networks coupled to inputs of said power amplifiers, wherein said harmonic control circuit networks enable a staggered-bias of said power amplifiers and operate to increase real power transfer to a fundamental frequency of said output and to decrease real power transfer to harmonic frequencies of said output.
2. The apparatus of claim 1 , further comprising:
a quadrature generator coupled to said modulation circuitry.
3. The apparatus of claim 2 , wherein said quadrature generator comprises:
circuitry to generate clock signals.
4. The apparatus of claim 3 , wherein said modulation circuitry comprise:
circuitry to generate substantially constant envelope signals using said clock signals and transfer function signals generated by said transfer function module.
5. The apparatus of claim 4 , wherein said power amplification stage comprises:
circuitry to amplify and combine said substantially constant envelope signals to generate said output.
6. The apparatus of claim 1 , wherein said power amplifiers comprise:
a plurality of multiple-input single-output (MISO) amplifiers.
7. The apparatus of claim 1 , further comprising:
biasing circuitry coupled to said power amplifiers.
8. The apparatus of claim 7 , wherein said biasing circuitry comprises:
circuitry to generate at least one bias signal to control current flow through said power amplifiers according to a desired output power level and output signal envelope.
9. The apparatus of claim 1 , wherein said power amplification stage also comprises:
a pre-driver stage coupled to said modulation circuitry; and
a driver stage coupled to said pre-driver stage and said power amplifiers.
10. The apparatus of claim 9 , further comprising:
biasing circuitry coupled to said pre-driver stage, said driver stage and said power amplifiers.
11. The apparatus of claim 10 , wherein said biasing circuitry comprises:
circuitry to generate different bias control signals for said pre-driver stage, said driver stage, and said power amplifiers.
12. The apparatus of claim 1 , wherein said harmonic control circuitry comprises:
circuitry to control a frequency spectrum of said output of said apparatus.
13. The apparatus of claim 1 , wherein said apparatus represents a Cartesian 4-branch power amplifier.
14. The apparatus of claim 13 , wherein said transfer function module comprises:
circuitry to generate Cartesian 4-branch power amplification transfer function signals.
15. The apparatus of claim 1 , wherein said apparatus represents a Cartesian-Polar-Cartesian-Polar power amplifier.
16. The apparatus of claim 15 , wherein said transfer function module comprises:
circuitry to generate Cartesian-Polar-Cartesian-Polar power amplification transfer function signals.
17. The apparatus of claim 1 , wherein said apparatus represents a Direct Cartesian 2-branch power amplifier.
18. The apparatus of claim 17 , wherein said transfer function module comprises:
circuitry to generate Direct Cartesian 2-branch power amplification transfer function signals.
19. A method for at least one of power transmission, modulation, and amplification, comprising:
receiving a frequency reference signal;
receiving information;
generating a plurality of control signals using at least said received information;
generating a plurality of substantially constant envelope signals using at least said frequency reference signal and said control signals;
amplifying and combining said substantially constant envelope signals using a plurality of power amplifiers to create an output signal; and
biasing said plurality of power amplifiers at respective bias points so as to cause a staggered bias of said power amplifiers, wherein said staggered bias of said power amplifiers increases real power transfer to a fundamental frequency of said output signal and decreases real power transfer to harmonic frequencies of said output signal.
20. The method of claim 19 , wherein receiving a frequency reference signal comprises receiving a clock signal.
21. The method of claim 19 , wherein receiving information comprises receiving in-phase (I) and quadrature-phase (Q) baseband signals.
22. The method of claim 19 , wherein generating a plurality of control signals using at least said received information comprises generating a plurality of transfer function signals.
23. The method of claim 19 , wherein generating a plurality of substantially constant envelope signals comprises modulating said control signals and said frequency reference signal.
24. The method of claim 19 , wherein said power amplifiers comprise a plurality of multiple-input single-output (MISO) amplifiers.
25. The method of claim 19 , further comprising:
generating at least one bias signal to control current flow through said power amplifiers according to a desired output power level and output signal envelope.
26. The method of claim 19 , wherein said biasing step comprises:
controlling a frequency spectrum of said output signal.
27. The method of claim 19 , wherein said biasing step comprises biasing said power amplifier at different respective bias points.
28. The method of claim 19 , wherein said biasing step comprises biasing said power amplifiers so as to cause a staggered-switching of said substantially constant envelope signals.