Systems and methods for phase shifting signals
According to various embodiments, a quadrature hybrid coupler included as part of a phase shifter is used to provide variable phase shift to an input signal. The quadrature hybrid coupler includes an input port, an output port, and two terminated ports. The phase shifter includes one or more static lumped elements connected to the QHC to reduce at least one electrical dimension of the QHC to substantially less than a quarter wavelength. The phase shifter also include one or more variable lumped elements connected to the QHC to provide a variable phase shift to the input signal between the input port and the output port of the QHC.
1. A phase shifter, comprising:
a quadrature hybrid coupler (QHC) that includes an input port, an output port, and two terminated ports;
one or more static lumped elements connected to the QHC, wherein an inclusion of the one or more static lumped elements with the QHC sets at least one electrical dimension of the QHC at substantially less than a quarter wavelength of an operating frequency of the QHC; and
one or more variable lumped elements connected to the QHC and configured to provide a variable phase shift between the input port and the output port.
2. The phase shifter of claim 1 , wherein the one or more variable lumped elements include one or more variable reactance devices or materials.
3. The phase shifter of claim 2 , wherein the one or more variable reactance devices are variable responsive to control inputs.
4. The phase shifter of claim 2 , wherein the one or more variable lumped elements include one or more varactor diodes.
5. The phase shifter of claim 4 , wherein the variable phase shift between the input port and the output port is adjusted by controlling biases applied to the one or more varactor diodes to adjust capacitances of the one or more varactor diodes.
6. The phase shifter of claim 1 , wherein the one or more static lumped elements include one or more static shunt capacitors.
7. The phase shifter of claim 1 , wherein the variable phase shift has a tuning range between 90° to 180°.
8. The phase shifter of claim 1 , wherein the QHC has a footprint less than or equal to one tenth of an operating wavelength of the operating frequency of the QHC by one tenth of the operating wavelength of the operating frequency of the QHC.
9. The phase shifter of claim 8 , wherein the operating frequency of the QHC is between 5.8 GHz and 5.9 GHz.
10. The phase shifter of claim 8 , wherein the operating frequency of the QHC is between 24 GHz and 24.5 GHz.
11. The phase shifter of claim 8 , wherein the operating frequency of the QHC is a frequency band within a frequency range of greater than 0 GHz and less than or equal to 24.5 GHz.
12. The phase shifter of claim 8 , wherein the QHC has a footprint less than or equal to 3 millimeters by 3 millimeters.
13. The phase shifter of claim 1 , wherein the QHC includes a first transmission line, a second transmission line, a third transmission line, and a fourth transmission line, the first and third transmission lines having electrical lengths less than or equal to one eighth wavelength and the second and fourth transmission lines having electrical lengths less than or equal to one sixteenth wavelength.
14. The phase shifter of claim 13 , wherein the first, second, third, and fourth transmission lines are printed as microstrips in a printed circuit board and at least one of the one or more static lumped elements and the one or more variable lumped elements are mounted onto the printed circuit board.
15. The phase shifter of claim 1 , wherein the one or more static lumped elements include one or more lumped inductors.
16. The phase shifter of claim 1 , wherein the phase shifter is configured to control the variable phase shift using an analog control signal.
17. The phase shifter of claim 16 , wherein the analog control signal is converted from a digital control signal.
18. The phase shifter of claim 1 , wherein the variable phase shift is applied to an RF signal used to wirelessly transmit radio waves for wirelessly transferring power.
19. A method comprising:
receiving a signal at an input port of a quadrature hybrid coupler (QHC) included as part of a phase shifter, the QHC including an output port, and two terminated ports, the phase shifter including:
one or more static lumped elements connected to the QHC, wherein an inclusion of the one or more static lumped elements with the QHC sets at least one electrical dimension of the QHC at substantially less than a quarter wavelength of a frequency of the signal; and
one or more variable lumped elements connected to the QHC and configured to provide a variable phase shift to signals including the signal between the input port and the output port; and
adjusting the variable phase shift between the input port and the output port using the one or more variable lumped elements as part of controlling the phase shifter.
20. The method of claim 19 , wherein the one or more variable lumped elements include one or more variable reactance devices or materials.
21. The method of claim 20 , wherein the one or more variable reactance devices are variable responsive to control inputs.
22. The method of claim 20 , wherein the one or more variable lumped elements include one or more varactor diodes.
23. The method of claim 22 , wherein the variable phase shift between the input port and the output port is adjusted by controlling biases applied to the one or more varactor diodes to adjust capacitances of the one or more varactor diodes.
24. The method of claim 19 , wherein the one or more static lumped elements include one or more static shunt capacitors.
25. The method of claim 19 , wherein the variable phase shift is applied to an RF signal used to wirelessly transmit radio waves for wirelessly transferring power.
26. A system comprising:
an array of phase shifters comprising a plurality of quadrature hybrid couplers (QHCs) that each include an input port, an output port, and two terminated ports, one or more static lumped elements connected to the QHCs, and one or more variable lumped elements connected to the QHCs and configured to provide variable phase shifts between the input ports and the output ports, wherein an inclusion of the one or more static lumped elements with each of the QHCs sets at least one electrical dimension of each of the QHCs at substantially less than a quarter wavelength of an operating frequency of the QHC; and
a controller for controlling the array of phase shifters by controlling the variable phase shifts of the array of phase shifters.
27. The system of claim 26 , wherein the one or more variable lumped elements include one or more variable reactance devices or materials.
28. The system of claim 27 , wherein the one or more variable reactance devices are variable responsive to control inputs.
29. The system of claim 27 , wherein the one or more variable lumped elements include one or more varactor diodes.
30. The system of claim 29 , wherein the variable phase shifts between the input port and the output port are adjusted by controlling biases applied to the one or more varactor diodes to adjust capacitances of the one or more varactor diodes.
31. The system of claim 26 , wherein the static lumped elements include one or more static shunt capacitors.
32. The system of claim 26 , wherein at least one of the QHCs of the array of phase shifters include a first transmission line, a second transmission line, a third transmission line, and a fourth transmission line, the first and third transmission lines having electrical lengths less than or equal to one eighth wavelength and the second and fourth transmission lines having electrical lengths less than or equal to one sixteenth wavelength.
33. The system of claim 32 , wherein the first, second, third, and fourth transmission lines are printed as microstrips in a printed circuit board and at least one of the one or more static lumped elements and the one or more variable lumped elements are mounted onto the printed circuit board.
34. The system of claim 26 , wherein the one or more static lumped elements include one or more lumped inductors.
35. The system of claim 26 , wherein the array of phase shifters are configured to control the variable phase shifts according to analog control signals.
36. The system of claim 35 , wherein the analog control signals are converted from digital control signals.
37. The system of claim 26 , wherein the variable phase shifts are applied to RF signals used to transmit radio waves for wirelessly transferring power and the array of phase shifters are configured to wirelessly transfer the power.
38. The system of claim 26 , wherein at least two of the phase shifters in the array of phase shifters are configured to, in combination as a first phase shifting stage and a second phase shifting stage, provide a variable phase shift of the variable phase shifts between the input ports and the output ports.
39. The system of claim 38 , wherein the at least two of the phase shifters are configured to provide a tuning range of at least 360° in the variable phase shifts between the input ports and the output ports.
40. The system of claim 39 , wherein the at least two of the phase shifters are coupled in series to provide the tuning range of at least 360° in the variable phase shifts between the input ports and the output ports.
41. The system of claim 26 , wherein the controller is configured to control the array of phase shifters to adjust the variable phase shifts in order to steer an RF beam formed using RF signals phase shifted by the array of phase shifters.
42. The system of claim 26 , further comprising an array of amplifiers coupled to the array of phase shifters, the array of amplifiers configured to amplify signals shifted by the array of phase shifters to create amplified signals.
43. The system of claim 42 , further comprising an array of antennas coupled to the array of phase shifters, the array of antennas configured to transmit electromagnetic radiation using the amplified signals.