What is claimed is:
1. A method for processing signals in an RF subsystem to eliminate the need for a low noise amplifier therein, the method comprising:
providing a plurality of intercoupled micromechanical devices; and
vibrating the micromechanical devices to initially pass a desired frequency range of signals while substantially attenuating signals outside the desired frequency range and then to convert and filter the desired frequency range of signals without the need for the low noise amplifier.
2. The method as claimed in claim 1 wherein the low noise amplifier is an RF low noise amplifier.
3. An RF receiver subsystem which eliminates the need for a low noise amplifier therein, the subsystem comprising:
an image-reject vibrating micromechanical filter for passing a desired frequency range of signals while substantially attenuating signals outside the desired frequency range; and
a vibrating micromechanical mixer-filter coupled to the filter and adapted to be coupled to electronics for converting and filtering the desired frequency range of signals without the need for the low noise amplifier.
4. The subsystem as claimed in claim 3 wherein the low noise amplifier is an RF low noise amplifier.
5. The subsystem as claimed in claim 3 wherein the filter is a relatively wide band filter and the mixer-filter is a narrow band mixer-filter.
6. An RF receiver subsystem which eliminates the need for a low noise amplifier, the subsystem comprising:
a vibrating micromechanical frequency range selector for passing a desired frequency range of signals while substantially attenuating signals outside the desired frequency range; and
a vibrating micromechanical mixer-filter coupled to the selector and adapted to be connected to electronics for converting and filtering the desired frequency range of signals without the need for the low noise amplifier.
7. The subsystem as claimed in claim 6 wherein the low noise amplifier is an RF low noise amplifier.
8. An RF transceiver subsystem which substantially reduces the need for RF front-end power, the subsystem comprising:
a vibrating micromechanical frequency range selector for passing a desired frequency range of signals while substantially attenuating signals outside the desired frequency range; and
a vibrating micromechanical mixer-filter coupled to the selector and adapted to be connected to electronics for converting and filtering signals wherein the need for RF front-end power is substantially reduced.
9. In an RF receiver subsystem, a micromechanical mixer-filter apparatus for converting and filtering an information signal having a frequency without the need for a front end filter, the apparatus comprising:
a mixing micromechanical transducer having a first port for receiving the information signal, a second port for receiving an AC signal having a desired frequency and an output port; and
a micromechanical resonator coupled to the transducer wherein the apparatus converts the frequency of the information signal based on the desired frequency and filters the information signal without the need for a front end filter.
10. The apparatus as claimed in claim 9 wherein the apparatus also adds gain to the information signal.
11. The apparatus as claimed in claim 9 wherein the transducer and the resonator are intercoupled by a non-conductive part to isolate the first and second ports.
12. The apparatus as claimed in claim 9 further comprising means for isolating each of the ports from each of the other ports.
13. The apparatus as claimed in claim 9 wherein the resonator is switchable and tunable.
14. The apparatus as claimed in claim 9 wherein the apparatus is an image-reject mixer filter that initially rejects an image while mixing and then filters.
15. In an RF receiver subsystem, a method for converting and filtering an information signal having a frequency without the need for a front end filter, the method comprising:
providing a micromechanical device having a first port for receiving the information signal, a second port for receiving an AC signal having a desired frequency and an output port; and
vibrating the micromechanical device so that the micromechanical device converts the frequency of the information signal based on the desired frequency and filters the information signal.
16. The method of claim 15 further comprising isolating the first port from the second port.
17. The method of claim 15 further comprising isolating each of the ports from each of the other ports.
18. The method of claim 15 wherein the micromechanical device is vibrated to also add gain to the information signal.
19. The method of claim 15 wherein the device is switchable and tunable.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A current transformer for supplying power to electronic controller, comprising:
a first core magnetic circuit and a second core magnetic circuit independent of each other, wherein the first core magnetic circuit is a closed loop formed by connecting a U-shaped core and a linear core, and a primary core-extending conductor extends through the closed loop of the first core magnetic circuit, and a secondary winding for power supply is wound on the linear core of the first core magnetic circuit; and
a second core magnetic circuit having an opening shape is disposed in parallel to the linear core of the first core magnetic circuit, and the open end of the second core magnetic circuit is coupled to the first core magnetic circuit through air gaps, wherein,
said area of the cross section of the linear core is less than that of the cross section of the U-shaped core, so that the linear core can be magnetically saturated earlier than the U-shaped core.
2. The current transformer for supplying power to electronic controller according to claim 1, wherein said area of the cross section of the U-shaped core is 1.2 to 3 times of that of the cross section of the linear core.
3. The current transformer for supplying power to electronic controller according to claim 1, wherein
said centerline length of the U-shaped core is 1.5 to 4 times of that of the linear core;
said U-shaped core and the linear core of the first core magnetic circuit have a spacing of 2-3 mm from the primary core-extending conductor surrounded by the first core magnetic circuit, so that excellent electrical isolation is formed between the first core magnetic circuit and the primary core-extending conductor surrounded by the first core magnetic circuit, and simultaneously, the first core magnetic circuit surrounding the primary conductor has the shortest length.
4. The current transformer for supplying power to electronic controller according to claim 1, wherein when the linear core is just magnetically saturated, a corresponding primary current I1 is 0.8 to 1.2 times of a rated current In of a primary main circuit.
5. The current transformer for supplying power to electronic controller according to claim 1, wherein said second core magnetic circuit and the first core magnetic circuit are disposed in a coplanar manner, so that magnetic flux flowing between the first core magnetic circuit and the second core magnetic circuit is maintained in the original direction.
6. The current transformer for supplying power to electronic controller according to claim 1, wherein two air gaps between the open end of the second core magnetic circuit and the first core magnetic circuit are fixed air gaps, which are respectively located at the two intersections of the linear core and the U-shaped core and also located at the two sides of the secondary winding for power supply.
7. The current transformer for supplying power to electronic controller according to claim 6, wherein said two fixed air gaps have a thickness from 0.1 mm to 2 mm.
8. The current transformer for supplying power to electronic controller according to claim 1, wherein said two fixed air gaps are equivalent in thickness and respectively filled with solid non-ferromagnetic matters.
9. The current transformer for supplying power to electronic controller according to claim 1, wherein said area of the cross section of the core of the second core magnetic circuit is equal to that of the cross section of the U-shaped core of the first core magnetic circuit.
10. A current transformer for supplying power to electronic controller, comprising a first core magnetic circuit and a second core magnetic circuit, wherein the first core magnetic circuit is a closed loop formed by connecting a U-shaped core and a linear core, and a primary core-extending conductor extends through the closed loop, and a secondary winding for power supply is wound on the linear core; a second core magnetic circuit having an opening shape is disposed in parallel to the linear core, and the open end of the second core magnetic circuit is coupled to the first core magnetic circuit through an air gap, wherein
the area of the cross section of the linear core is less than that of the cross section of the U-shaped core, so that the linear core can be magnetically saturated earlier than the U-shaped core;
the centerline length of the U-shaped core is 1.5 to 4 times of that of the linear core;
said open end of the second core magnetic circuit is connected in parallel with the intersection of the linear core and the U-shaped core located at one side of the secondary winding for power supply, and the other end of the second core magnetic circuit is coupled, through the fixed air gap, to the intersection of the linear core and the U-shaped core located at the other side of the secondary winding for power supply.