ULTRA-BROAD BANDWIDTH MATCHING TECHNIQUE
A multicomponent network may be added to a transmission line in a high-frequency circuit to transform a first impedance of a downstream circuit element to second impedance that better matches the impedance of an upstream circuit element. The multicomponent network may be added at a distance more than one-quarter wavelength from the downstream circuit element, and can tighten a frequency response of the impedance-transforming circuit to maintain low Q values and low VSWR values over a broad range of frequencies.
1 . An impedance-transforming circuit that is configured to operate at frequencies between 500 MHz and 6 GHz, the impedance-transforming circuit comprising:
a multicomponent network comprising passive circuit elements integrated on a substrate; and
at least one transmission line configured to connect between the multicomponent network and a circuit element such that the multicomponent network is at least one-quarter wavelength from the circuit element, wherein the multicomponent network and the at least one transmission line transform an input impedance of the circuit element to provide a reduced voltage-to-standing-wave-ratio (VSWR) over a bandwidth that lies at least partly within the frequencies.
2 . The impedance-transforming circuit of claim 1 , wherein the substrate comprises a printed circuit board or pallet.
3 . The impedance-transforming circuit of claim 1 , wherein the substrate comprises one or more semiconductor chips.
4 . The impedance-transforming circuit of claim 1 , wherein the reduced VSWR is less than or approximately equal to 2.
5 . The impedance-transforming circuit of claim 1 , wherein the multicomponent network comprises at least two passive circuit elements.
6 . The impedance-transforming circuit of claim 1 , further comprising a source having a second impedance at an output that is connected to the impedance-transforming circuit, wherein the reduced VSWR is less than or approximately equal to 2 and the bandwidth is greater than 800 MHz.
7 . The impedance-transforming circuit of claim 1 , wherein the reduced VSWR is less than or approximately equal to 2 and the bandwidth is between 1 GHz and 2 GHz.
8 . The impedance-transforming circuit of claim 1 , wherein the multicomponent network comprises a three-element π network.
9 . The impedance-transforming circuit of claim 1 , wherein the multicomponent network comprises a T network.
10 . The impedance-transforming circuit of claim 1 , wherein the multicomponent network comprises an LCC network.
11 . The impedance-transforming circuit of claim 1 , wherein the at least one transmission line comprises two transmission line sections having different impedances.
12 . The impedance-transforming circuit of claim 1 , further comprising a source connected to the multicomponent network, wherein the source comprises a gallium-nitride amplifier.
13 . The impedance-transforming circuit of claim 1 , further comprising a source connected to the multicomponent network, wherein the source is included in a wireless communication device.
14 . The impedance-transforming circuit of claim 1 , wherein the reduced VSWR is less than or approximately equal to 2 and the bandwidth is centered at approximately 750 MHz and has a width between approximately 325 MHz and approximately 750 MHz.
15 . The impedance-transforming circuit of claim 1 , wherein the reduced VSWR is less than or approximately equal to 2 and the bandwidth is centered at approximately 2.2 GHz and has a width between approximately 1.1 GHz and approximately 2.2 GHz.
16 . The impedance-transforming circuit of claim 1 , wherein the reduced VSWR is less than or approximately equal to 2 and the bandwidth is centered at approximately 2.7 GHz and has a width between approximately 1.3 GHz and approximately 2.7 GHz.
17 . The impedance-transforming circuit of claim 1 , wherein the reduced VSWR is less than or approximately equal to 2 and the bandwidth is centered at approximately 3.8 GHz and has a width between approximately 1.9 GHz and approximately 3.8 GHz.
18 . A method for transforming an impedance of a circuit element in a high-frequency circuit, the method comprising:
receiving a signal having a frequency component between 500 MHz and 6 GHz at a multicomponent network comprising passive circuit elements;
providing the signal from the multicomponent network to at least one transmission line;
providing the signal from the at least one transmission line to the circuit element, wherein the multicomponent network is at least one-quarter wavelength from the circuit element; and
transforming, by the multicomponent network and the at least one transmission line, the input impedance of the circuit element to provide a reduced VSWR over a bandwidth.
19 . The method of claim 18 , wherein the reduced VSWR is less than or approximately equal to 2.
20 . The method of claim 18 , wherein the multicomponent network comprises at least two passive circuit elements.
21 . The method of claim 18 , wherein the multicomponent network comprises a π network.
22 . The method of claim 18 , further comprising reflecting a voltage amount from the multicomponent network less than or equal to one-half of an incident voltage over a bandwidth greater than 800 MHz.
23 . The method of claim 18 , wherein the reduced VSWR is less than or approximately equal to 2 and the and the bandwidth is centered at approximately 750 MHz and has a width between approximately 325 MHz and approximately 750 MHz.
24 . The method of claim 18 , wherein the reduced VSWR is less than or approximately equal to 2 and the bandwidth is centered at approximately 2.2 GHz and has a width between approximately 1.1 GHz and approximately 2.2 GHz.
25 . The method of claim 18 , wherein the reduced VSWR is less than or approximately equal to 2 and the bandwidth is centered at approximately 2.7 GHz and has a width between approximately 1.3 GHz and approximately 2.7 GHz.
26 . The method of claim 18 , wherein the reduced VSWR is less than or approximately equal to 2 and the bandwidth is centered at approximately 3.8 GHz and has a width between approximately 1.9 GHz and approximately 3.8 GHz.
27 . The method of claim 18 , wherein the multicomponent network comprises a T network.
28 . The method of claim 18 , wherein the multicomponent network comprises an LCC network.
29 . The method of claim 18 , further comprising generating the signal that is received at the multicomponent network with a gallium-nitride amplifier.
30 . The method of claim 29 , further comprising transmitting the signal wirelessly.