High frequency power divider / combiner circuit

Abstract

A high frequency power divider circuit for distributing an input signal to two or more signal output ports, comprising: a rat race coupler, wherein the rat race coupler is configured to couple an input signal provided at an input port of the rat race coupler to a first output of the rat race coupler and to a second output of the rat race coupler; a first coupling structure coupled to the first output of the rat race coupler to couple the first output of the rat race coupler with a first signal output port; and a second coupling structure coupled to the second output of the rat race coupler to couple the second output of the rat race coupler with a second signal output port; wherein a characteristic impedance of a first transmission line portion between the input port of the rat race coupler and the first output deviates in a first direction from a nominal loop impedance of the rat race coupler, and wherein a characteristic impedance of a second transmission line portion between the input port of the rat race coupler and the second output deviates in a second direction from the nominal loop impedance of the rat race coupler, the second direction being opposite to the first direction.

Description

Technical Field

[0001] Embodiments of the present invention relate to a high-frequency power divider for distributing an input signal to two or more signal outputs and a high-frequency power combiner circuit for obtaining an output signal based on an input signal from two or more signal inputs. Background Technology

[0002] Power divider / combiner circuits are widely used to divide or combine high-frequency signals and are important devices in wireless communication systems, serving as a major component of microwave circuits. Several possible structures can be used to design RF power dividers (combiners). The following section provides a brief overview of the possible structures for power dividers.

[0003] Figure 1 illustrates possible structures for radio frequency (RF) power dividers. Figure 1(A) shows a Wilkinson divider, Figure 1(B) shows a rat-race divider, Figure 1(C) shows a branch line divider, and Figure 1(D) shows a Giselle divider. In Figure 1, reference symbols beginning with "P" indicate RF power divider ports (RF ports), i.e., signal input / output ports. All elements indicated by reference symbols beginning with "R" in Figure 1 are resistors. The resistance of all resistors is equal to the nominal impedance of the circuit (R0, typically 50Ω), except for R1A, which is 2*R0. All elements in Figure 1 with reference symbols beginning with "TL" are transmission lines or parts of transmission lines. All of these are a quarter wavelength (λ / 4) at the center of the operating center frequency (f0), excluding TL4B, which is three-quarter wavelength in length. Transmission lines TL1A, TL2A, TL1B, TL2B, TL3B, and TL4B have a characteristic impedance Z0 = R0 * √2; transmission lines TL2C, TL4C, TL3D, and TL4D have a characteristic impedance Z0 = R0; transmission lines TL1C and TL3C have a characteristic impedance Z0 = R0 / √2; and transmission lines TL5D and TL6D have a characteristic impedance Z0 = R0 / 2. The depicted structure is similar to a printed circuit implementation of transmission lines (e.g., microstrip, stripline). However, all structures can be implemented using any type of TEM or quasi-TEM transmission line, such as coaxial cable, two-wire line, microstrip, stripline, coplanar waveguide, etc.

[0004] Figure 2 shows the theoretical performance of the structure shown in Figure 1. Figure 2(A) shows the theoretical performance of the Wilkinson distributor shown in Figure 1(A), Figure 2(B) shows the theoretical performance of the mouse-circle distributor shown in Figure 1(B), Figure 2(C) shows the theoretical performance of the branch line shown in Figure 1(C), and Figure 2(D) shows the theoretical performance of the Giselle distributor shown in Figure 1(D). In Figure 2, for all graphs: the left y-axis is the transmission coefficient between non-isolated ports. The right y-axis is the transmission coefficient between isolated ports and the return loss at different RF ports. The curve labels have the same line type as the corresponding curves and are placed close to their respective y-axis. All curves are calculated using ideal components. In Figure 2, the theoretical performance of the structure is expressed using the scattering parameter S. ij To describe it.

[0005] Figure 3 illustrates the further theoretical performance of these structures. Figure 3(A) shows the further theoretical performance of the Wilkinson power divider. As shown in Figure 3(A), the Wilkinson power divider is symmetrical (see Figure 1(A)), therefore the scattering parameters are related as S21 = S31, and thus there is no imbalance in amplitude or phase.

[0006] Figure 3(B) shows further theoretical performance of the Giselle distributor. As shown in Figure 3(B), the Giselle distributor is also symmetrical (see Figure 1(D)), therefore the scattering parameters are related as S21 = S31: there is no imbalance in amplitude and phase.

[0007] When considering the evaluation of operating bandwidth (Δf), that is, how wide the operating bandwidth (Δf) of each circuit is, the most meaningful parameter is the relative bandwidth (Δf / f0). It can be defined in many ways by return loss, amplitude or phase imbalance. Figure 4 A table is shown indicating the relative bandwidths of the four circuits depicted in Figure 1, assuming:

[0008] 1) 15dB return loss ( Figure 4 (Column 2 of the table shown)

[0009] 2) 0.5dB amplitude imbalance ( Figure 4 The third and fourth columns of the table shown contain Figure 4

[0010] The corresponding phase imbalance is shown in the table below.

[0011] like Figure 4 As shown, Wilkinson and Giselle are not unbalanced, that is, their relative bandwidth in this respect is infinite.

[0012] Figure 5 shows a schematic diagram illustrating an example of the physical layout of the power divider shown in Figure 1. Figure 5(A) shows the physical layout of the Wilkinson divider as shown in Figure 1(A), Figure 5(B) shows the mouse-circle physical layout as shown in Figure 1(B), Figure 5(C) shows the physical layout of the branch line as shown in Figure 1(C), and Figure 5(D) shows the physical layout of the Giselle divider as shown in Figure 1(D). In Figure 5, for the physical layout shown, i.e., the actual layout of the microstrip design, for example, the center frequency f0 = 30 GHz, the substrate has a relative permittivity (εr) = 3.5, a height (h) = 0.25 mm, and a metal thickness (t) = 20 μm.

[0013] Considering broadband applications, the Wilkinson divider is likely the primary or first candidate. A major problem associated with the Wilkinson divider is the need for a bulk resistor R1A, i.e., << λ / 4 in length (see Figure 5(A)). In the case shown in Figure 5(A), the size of R1A is close to the minimum possible for this technique, for example, 0.4 × 0.5 mm, and is already comparable to the lengths of the transmission line sections TL1A and TL2A, which are equal to λ / 4, i.e., one-quarter of the wavelength. Compared to the ideal situation, the relatively large resistor leads to degradation in isolation (indicated by scattering parameter S32), insertion loss (indicated by scattering parameters S21, S31), and return loss (indicated by scattering parameters S11, S22, S33). Therefore, the problem becomes more severe as the center frequency increases.

[0014] Furthermore, transmission lines TL1A and TL2A should be isolated: this is contrary to the requirement of small R1A. To minimize coupling (which reduces S11, S22, S33, S32), curved geometries are often used (as in this example). However, this is not always possible, especially at very high frequencies (i.e., with very short transmission lines TL1A, TL2A).

[0015] Unlike Wilkinson dividers, other power divider circuits—namely, the squirrel-circle, branch-line, and Giselle dividers shown in Figure 5—do not require bulk resistors. Instead, they only require ground termination R0, and these terminations—in principle—have no conceptual limitations on their size; for example, an infinitely long transmission line with Z0 = R0 is one possible implementation of such termination. However, the relative bandwidth of these circuits is always smaller than that of Wilkinson dividers: from largest to smallest, the order is Wilkinson divider, Giselle divider, squirrel-circle, and branch-line.

[0016] Furthermore, there are strong discontinuities at the junctions of the branch lines: first port P1—transmission line TL1C—transmission line TL4C, second port P2—transmission line TL2C—transmission line TL3C, third port P3—transmission line TL1C—transmission line TL2C, and resistor R1C—transmission line TL3C—transmission line TL4C. Additionally, the Gissel distributor also exhibits strong discontinuities at the junctions of transmission line TL4D—resistor R2D—transmission line TL6D, and transmission line TL3D—resistor R1D—transmission line TL5D. Due to the low characteristic impedance, these strong discontinuities at the junctions are realized: Z0 = R0 / √2 for transmission lines TL1C and TL3C, and Z0 = R0 / 2 for transmission lines TL5D and TL6D, resulting in larger widths. At high frequencies, the dimensions of these T-junctions become comparable to the transmission line length. Circuit performance becomes critical, unpredictable, and extremely sensitive to manufacturing tolerances.

[0017] Due to the high impedance Z0 of the transmission lines TL1B,…,TL4B (and therefore their narrow width), the mouse-loop configuration exhibits less of this problem. As shown in Figure 5(B), discontinuities can be further minimized by making the feed lines gradually thinner.

[0018] Figure 6 shows a modified example of a branch line. Figure 6(a1) shows a standard branch line type distributor, and Figure 6(a2) shows a modified branch line type distributor, namely, an in-phase branch line. The branch line output ports P2, P3 are 90° phase-shifted instead of in-phase. If this is required, a compensation network is needed. An example is the Schiffman phase shifter shown in Figure 6(a2): transmission lines TL5C, TL6C are coupled lines with an electrical length λ / 4 at the center frequency f0 and have an even (odd) mode impedance Z0E (Z0O), such that Z0E*Z0O = R0. 2 Transmission line section TL7C is a transmission line section with an electrical length of λ / 4 at the center frequency f0, and Z0 = R0. By swapping the positions of transmission lines TL5C, TL6C, and transmission line section TL7C, a 180° offset between output ports P2 and P3 can be obtained. In all cases, the bandwidth of the branch lines remains the same. Summary of the Invention

[0019] Therefore, considering the aforementioned issues, such as operating bandwidth, phase imbalance, predictable circuit performance, and manufacturing tolerances, the squirrel-coil coupler appears to be a suitable solution.

[0020] Therefore, one object of the present invention is to create a concept that facilitates the implementation of high-frequency power divider / combiner circuits by using a mouse-loop coupler.

[0021] According to one embodiment of the present invention, a high-frequency power divider circuit is provided for distributing an input signal to two or more signal output ports. The high-frequency divider circuit includes a squirrel-coil coupler configured to couple an input signal provided at an input port of the squirrel-coil coupler to a first output of the squirrel-coil coupler and to a second output of the squirrel-coil coupler; a first coupling structure coupled to the first output of the squirrel-coil coupler to couple the first output of the squirrel-coil coupler to a first signal output port; and a second coupling structure coupled to the second output of the squirrel-coil coupler to couple the second output of the squirrel-coil coupler to a second signal output port; wherein the characteristic impedance of a first transmission line portion between the input port and the first output of the squirrel-coil coupler deviates from the nominal ring impedance of the squirrel-coil coupler in a first direction, and wherein the characteristic impedance of a second transmission line portion between the input port and the second output of the squirrel-coil coupler deviates from the nominal ring impedance of the squirrel-coil coupler in a second direction, the second direction being opposite to the first direction.

[0022] According to the concept of the present invention, the characteristic impedance of the second transmission line portion between the input port and the second output of the mouse-coil coupler deviates from the nominal ring impedance of the mouse-coil coupler in a second direction opposite to the first direction, and is greater than the nominal ring impedance. Therefore, at the design frequency of the mouse-coil coupler, the signal power of the input signal coupled to the first output port is greater than the signal power coupled to the second output port. Furthermore, when the frequency of the input signal is far from the design frequency of the mouse-coil coupler within the environment of the design frequency, the signal power of the input signal coupled to the first output port decreases, thus becoming less than the signal power of the input signal coupled to the second output port.

[0023] In a preferred embodiment, the characteristic impedance of the third transmission line section between the second output of the mouse-coil coupler and the other port of the mouse-coil coupler deviates from the nominal toroidal impedance in the same direction as the characteristic impedance of the first transmission line section. Furthermore, the characteristic impedance of the fourth transmission line section between the first output of the mouse-coil coupler and the other port of the mouse-coil coupler deviates from the nominal toroidal impedance in the same direction as the characteristic impedance of the second transmission line section.

[0024] In a preferred embodiment, the difference between the characteristic impedance of the first transmission line portion and the characteristic impedance of the third transmission line portion does not exceed ±25% of the characteristic impedance of the first transmission line portion and the characteristic impedance of the second transmission line portion, or does not exceed ±10% of the characteristic impedance of the first transmission line portion and the characteristic impedance of the second transmission line portion.

[0025] In a preferred embodiment, the difference between the characteristic impedance of the second transmission line portion and the characteristic impedance of the fourth transmission line portion does not exceed ±25% of the characteristic impedance of the second transmission line portion and the characteristic impedance of the first transmission line portion, or does not exceed ±10% of the characteristic impedance of the second transmission line portion and the characteristic impedance of the first transmission line portion.

[0026] In a preferred embodiment, the product of the characteristic impedance of the first transmission line section or the characteristic impedance of the third transmission line section and the characteristic impedance of the second transmission line section or the characteristic impedance of the fourth transmission line section is equal to the square of the nominal toroidal impedance, with a tolerance of ±10%.

[0027] In a preferred embodiment, the characteristic impedance of the first transmission line section or the characteristic impedance of the third transmission line section is less than the characteristic impedance of the second transmission line section or the characteristic impedance of the fourth transmission line section. Furthermore, the deviation of the characteristic impedance from the nominal ring impedance is within ±20% or ±10% of the nominal ring impedance value.

[0028] In a preferred embodiment, the characteristic impedance values ​​of the first transmission line portion and the third transmission line portion deviate from the nominal ring impedance value by +1% to +20% or by +1% to +10%, and the characteristic impedance values ​​of the second transmission line portion and the fourth transmission line portion deviate from the nominal ring impedance value by -1% to -20% or by -1% to -10%, and vice versa.

[0029] According to one embodiment of the present invention, a high-frequency power divider circuit is provided for distributing an input signal to two or more signal output ports. The high-frequency power divider circuit includes: a mouse-coil coupler configured to couple an input signal provided at an input port of the mouse-coil coupler to a first output of the mouse-coil coupler and to a second output of the mouse-coil coupler; a first coupling structure coupled to the first output of the mouse-coil coupler to couple the first output of the mouse-coil coupler to a first signal output port; and a second coupling structure coupled to the second output of the mouse-coil coupler to couple the second output of the mouse-coil coupler to a second signal output port; wherein the first coupling structure and the second coupling structure are adapted to provide different phase shifts with frequency; wherein the first coupling structure includes a phase shifter adapted to at least partially compensate for frequency variations in the phase difference between the signals at the first output and the second output of the mouse-coil coupler in an environment at the design frequency of the mouse-coil coupler.

[0030] In a preferred embodiment, the second coupling structure includes a pair of coupled transmission lines, wherein a first end of the first coupled transmission line is connected to a second output of the mouse-coil coupler, wherein a second end of the first coupled transmission line is connected to a second end of the second coupled transmission line, the second end of the second coupled transmission line being adjacent to the second end of the first coupled transmission line, and wherein a first end of the second coupled transmission line is connected to a second signal output port, or constitutes a second signal output port.

[0031] In a preferred embodiment, a first end of the first coupled transmission line is connected to the second output of the mouse-coil coupler via another transmission line. Furthermore, the characteristic impedance of the other transmission line deviates from the reference impedance by no more than ±5% or ±10%. Additionally, the product of the even-mode impedance and the odd-mode impedance of the coupled transmission lines deviates from the square of the reference impedance by no more than ±5%, ±10%, or ±15%.

[0032] In a preferred embodiment, the electrical length of the coupled transmission line deviates from one-quarter of the wavelength at the design center frequency of the rat-coil coupler by no more than ±5% or ±10%. For example, in other words, the coupled transmission line is a λ / 4 transmission line at the design center frequency of the rat-coil coupler with a tolerance of ±5% or ±10%.

[0033] In a preferred embodiment, the length of the other transmission line is selected to decouple the stray field of the pair of coupled transmission lines from the mouse-loop coupler. Furthermore, the electrical length of the transmission line forming the first coupling structure is equal to the electrical length of the other transmission line plus half a wavelength, with a tolerance of ±1 / 10 of the wavelength.

[0034] According to one embodiment of the present invention, a high-frequency power combiner circuit is provided for obtaining an output signal based on input signals from two or more signal input ports. The high-frequency power combiner circuit includes: a mouse-coil coupler configured to provide an output signal at an output port based on a signal at a first input of the mouse-coil coupler and a signal at a second input of the mouse-coil coupler; a first coupling structure coupled to the first input of the mouse-coil coupler to couple the first input of the mouse-coil coupler to a first signal input port; and a second coupling structure coupled to the second input of the mouse-coil coupler to couple the second input of the mouse-coil coupler to a second signal input port; wherein the characteristic impedance of a first transmission line portion between the output port and the first input of the mouse-coil coupler deviates from the nominal toroidal impedance of the mouse-coil coupler in a first direction, and wherein the characteristic impedance of a second transmission line portion between the output port and the second input of the mouse-coil coupler deviates from the nominal toroidal impedance of the mouse-coil coupler in a second direction, the second direction being opposite to the first direction.

[0035] According to one embodiment of the present invention, there is a high-frequency power combiner circuit for obtaining an output signal based on input signals from two or more signal input ports. The high-frequency power combiner circuit includes: a squirrel-coil coupler configured to provide an output signal at an output port based on a signal at a first input of the squirrel-coil coupler and a signal at a second input of the squirrel-coil coupler; a first coupling structure coupled to the first input of the squirrel-coil coupler to couple the first input of the squirrel-coil coupler to a first signal input port; and a second coupling structure coupled to the second input of the squirrel-coil coupler to couple the second input of the squirrel-coil coupler to a second signal input port; wherein the first coupling structure and the second coupling structure are adapted to provide different phase shifts with frequency; wherein the first coupling structure includes a phase shifter adapted to at least partially compensate for the difference between the frequency variation from the first input to the output port of the squirrel-coil coupler and the frequency variation of the transmission characteristics from the second input to the output port of the squirrel-coil coupler in an environment of the design frequency of the squirrel-coil coupler, the frequency variation affecting the combination of signals at the first input and the second input of the squirrel-coil coupler. Attached Figure Description

[0036] Embodiments of the present invention will then be described with reference to the accompanying drawings, in which:

[0037] Figure 1 shows a schematic diagram of a possible structure of a radio frequency (RF) power divider according to the prior art;

[0038] Figure 2 shows a schematic diagram representing the theoretical performance of the structure shown in Figure 1;

[0039] Figure 3 shows the further theoretical performance of the structure shown in Figure 1;

[0040] Figure 4 A table showing the relative bandwidths of four circuits according to the structure shown in Figure 1 is presented;

[0041] Figure 5 shows a schematic diagram illustrating an example of the physical layout of the power divider shown in Figure 1;

[0042] Figure 6 shows an example of a modified branch line according to the prior art shown in Figure 1;

[0043] Figure 7 shows an example of a rat-loop coupler according to an embodiment of this application;

[0044] Figure 8 illustrates the performance of the modified rat-race coupler according to an embodiment of this application;

[0045] Figure 9A table is shown to illustrate the dependence of K on embodiments according to this application. GB The magnitude imbalance and relative bandwidth of the values;

[0046] Figure 10 The performance of the modified mouse-ring type according to an embodiment of this application is shown; and

[0047] Figure 11 Further performance of the modified mouse-ring type according to an embodiment of the present invention is shown. Detailed Implementation

[0048] Figure 7 illustrates an example of a mouse-coil coupler according to an embodiment of this application. Figure 7(a) shows a standard mouse-coil coupler, which is the same as that shown in Figure 1(B), and Figure 7(b) shows a modified mouse-coil coupler, i.e., an improved mouse-coil coupler.

[0049] As shown in Figure 7(b), the rat-race coupler couples the input signal provided at the input port P1 of the rat-race coupler to the first output of the rat-race coupler, for example, at the location where the transmission line section TL7B is connected to the rat-race coupler ring, and to the second output of the rat-race coupler, for example, at the location where the transmission line section TL8B is connected to the rat-race coupler ring; the first coupling structure, TL7B, is coupled to the first output of the rat-race coupler to couple the first output of the rat-race coupler to the first signal output port P2; and the second coupling structure, formed by transmission lines TL8B, TL5B, and TL6B, is coupled to the second output of the rat-race coupler to couple the second output of the rat-race coupler to the second signal output port P3; wherein, the characteristic impedance of the first transmission line section TL1B between the input port P1 and the first output of the rat-race coupler (e.g., Z0 = 1 / K) is... GB *sqrt(2)*R0, R0 is typically 50Ω, but not necessarily 50Ω) deviates from the nominal ring impedance of the mouse-ring coupler (e.g., sqrt(2)*R0) in the first direction, for example, less than the nominal ring impedance, and wherein the characteristic impedance of the second transmission line section TL2B between the input port P1 and the second output of the mouse-ring coupler (e.g., Z0 = K) GBThe *sqrt(2)*R0) deviates from the nominal ring impedance (e.g., sqrt(2)*R0) of the mouse-ring coupler in a second direction opposite to the first direction, for example, greater than the nominal ring impedance. As a result, at the design frequency of the mouse-ring coupler, the signal power coupled to the first output port P2 is greater than the signal power coupled to the second output port P3. And when the frequency of the input signal (within the design frequency environment) is far from the design frequency of the mouse-ring coupler, the signal power coupled to the first output port decreases, thus becoming less than the signal power coupled to the second output port.

[0050] The characteristic impedance of the third transmission line section TL3B between the second output of the squirrel-coil coupler and another port of the squirrel-coil coupler—for example, the terminated port—deviates from the nominal toroidal impedance in the same direction as the characteristic impedance of the first transmission line section TL1B. The characteristic impedance of the fourth transmission line section TL4B between the first output of the squirrel-coil coupler and another port of the squirrel-coil coupler—for example, the terminated port—deviates from the nominal toroidal impedance in the same direction as the characteristic impedance of the second transmission line section TL2B.

[0051] Furthermore, as shown in Figure 7(b), the rat-loop configuration itself is asymmetrical, therefore the phase shift between the second port P2 and the third port P3 is zero only at the center frequency f0. To smooth out the phase difference, a variant of the Schiffman phase shifter can be used, as shown in Figure 7(b). The transmission sections TL5B and TL6B are λ / 4 coupling lines at the center frequency f0, with even (odd) mode impedances Z0E (Z0O), thus Z0E*Z0O=R0 2 Transmission line section TL8B is a Z0 = R0 transmission, with a length sufficient to minimize the coupling between transmission line sections TL5B and TL6B and the mouse-loop itself. Transmission line section TL7B is a Z0 = R0 transmission, and its length is equal to TL8B + λ / 2 at the center frequency f0.

[0052] Figure 8 illustrates the performance of the modified mouse-ring coupler according to an embodiment of this application. As mentioned above, the nominal ring impedance is sqrt(2)*R0, and the characteristic impedances of the first transmission line portion TL1B and the third transmission line portion TL3B are Z0 = K. GB *sqrt(2)*R0, and the characteristic impedance of the second transmission line section TL2B and the characteristic impedance of the fourth transmission line section TL4B are Z0=K GB *sqrt(2)*R0. Figure 8(a) shows the values ​​of scattering parameters S21 and S31, Figure 8(b) shows the value of S31 / S21, and Figure 8(c) shows the absolute value of S31 / S21.

[0053] Figure 9 A table is shown to illustrate the dependence of K on embodiments according to this application. GB The values ​​are unbalanced in magnitude and relative bandwidth. In K GB When = 1, it is a traditional circuit structure. For example... Figure 9 As shown, a reasonable value for absolute amplitude balance can be between 1dB and 2dB. This means that K GB The reasonable range is limited to between 1 (i.e., conventional design) and approximately 1.1 (or 1 / 1.1). Furthermore, using 1 / K... GB Replace K GB This is almost equivalent to swapping the first signal output port P2 and the second signal output port P3. The result is as follows: Figure 9 The tables shown are very similar.

[0054] As a modification, the difference between the characteristic impedance of the first transmission line section TL1B and the characteristic impedance of the third transmission line section TL3B shall not exceed ±25% of the characteristic impedance of the first transmission line section TL1B and the characteristic impedance of the second transmission line section TL2B, or shall not exceed ±10% of the characteristic impedance of the first transmission line section TL1B and the characteristic impedance of the second transmission line section TL2B. Furthermore, the difference between the characteristic impedance of the second transmission line section TL2B and the characteristic impedance of the fourth transmission line section TL4B shall not exceed ±25% of the characteristic impedance of the second transmission line section TL2B and the characteristic impedance of the first transmission line section TL1B, or shall not exceed ±10% of the characteristic impedance of the second transmission line section TL2B and the characteristic impedance of the first transmission line section TL1B.

[0055] Furthermore, the product of the characteristic impedance of the first transmission line section TL1B or the characteristic impedance of the third transmission line section TL3B and the characteristic impedance of the second transmission line section TL2B or the fourth transmission line section TL4B is equal to the square of the nominal toroidal impedance, with a tolerance within ±10%. The characteristic impedance of the first transmission line section TL1B or the characteristic impedance of the third transmission line section TL3B is less than the characteristic impedance of the second transmission line section TL2B or the fourth transmission line section TL4B.

[0056] Furthermore, the deviation of the characteristic impedance from the nominal ring impedance is within ±20% or ±10% of the nominal ring impedance value. That is, the characteristic impedance values ​​of the first and third transmission line sections deviate from the nominal ring impedance value by +1% to +20% or +1% to +10%, and the characteristic impedance values ​​of the second and fourth transmission line sections deviate from the nominal ring impedance value by -1% to -20% or -1% to -10%, and vice versa.

[0057] As a further embodiment, the rat-loop configuration itself is asymmetrical (see Figure 7(b)), therefore the phase shift between the first signal output port P2 and the second signal output port P3 is zero only at the center frequency f0. To smooth out the phase difference, a variant of a Schiffman phase shifter can be used, as shown in Figure 7(b). The coupled transmission lines TL5B and TL6B are coupled lines with an electrical length λ / 4 at the center frequency f0 and an even (odd) mode impedance Z0E (Z0O), such that Z0E*Z0O = R0. 2 .

[0058] That is, according to an embodiment of the present invention, a high-frequency power divider circuit for distributing an input signal to two or more signal output ports is shown in FIG7(b). The circuit includes: a squirrel-loop coupler, wherein the squirrel-loop coupler is configured to couple an input signal provided at an input port (e.g., P1) of the squirrel-loop coupler to a location where a first output (e.g., TL7B) of the squirrel-loop coupler is connected to a squirrel-loop coupler ring, and to a location where a second output (e.g., TL8B) of the squirrel-loop coupler is connected to a squirrel-loop coupler ring; a first coupling structure, TL7B, which is coupled to the first output of the squirrel-loop coupler to couple the first output of the squirrel-loop coupler to a first signal output port P2; and a second coupling structure... The first coupling structure, configured by transmission lines TL8B, TL5B, and TL6B, is coupled to the second output of a squirrel-coil coupler to couple the second output of the squirrel-coil coupler to the second signal output port P3; wherein the first coupling structure and the second coupling structure are adapted to provide different phase shifts with frequency; wherein the first coupling structure includes a phase shifter adapted to at least partially compensate for frequency variations in the phase difference between the signals at the first output and the second output of the squirrel-coil coupler in an environment at the design frequency of the squirrel-coil coupler.

[0059] Furthermore, the second coupling structure includes a pair of coupling transmission lines TL6B and TL5B. The first end of the first coupling transmission line TL5B is connected to the second output of the mouse-coil coupler, for example, via TL8B. The second end of the first coupling transmission line is connected to the second end of the second coupling transmission line, which is adjacent to the second end of the first coupling transmission line. The first end of the second coupling transmission line TL6B is connected to the second signal output port, or forms the second signal output port P3. The first end of the first coupling transmission line TL5B is connected to the second output of the mouse-coil coupler via another transmission line TL8B (e.g., via TL8B).

[0060] Furthermore, the characteristic impedance of the other transmission line deviates from the reference impedance (e.g., 50Ω) by no more than ±5%, or by no more than ±10%. Additionally, the even-mode impedance Z of the coupled transmission lines...0E and the odd-mode impedance Z of the coupled transmission line 0O The product of the two impedances shall deviate from the square of the reference impedance by no more than ±5%, or no more than ±10%, or no more than ±15%.

[0061] As a modification, the electrical length of the coupled transmission lines deviates from one-quarter of the wavelength at the design center frequency of the squirrel-coil coupler by no more than ±5%, or no more than ±10%. In other words, the coupled transmission lines are λ / 4 transmission lines at the design center frequency of the squirrel-coil coupler, with a tolerance of ±5% or ±10%. Furthermore, the length of the other transmission line TL8B is selected to decouple the stray field of the coupled transmission lines from the squirrel-coil coupler. Additionally, the electrical length of the transmission line forming the first coupling structure is equal to the electrical length of the other transmission line TL8B plus half a wavelength, with a tolerance of ±1 / 10 of the wavelength.

[0062] Figure 10 The performance of the modified mouse-ring type according to an embodiment of this application is shown. Figure 10 As shown, modifications to Z0 of the transmission line sections TL1B, ..., TL4B have almost no effect on the phase. Furthermore, the addition of the phase compensation network has no effect on the amplitude.

[0063] Figure 11 The performance of the modified mouse-ring type according to embodiments of this application is also shown. For example... Figure 11 As shown, the addition of the phase compensation network, namely the addition of the first coupling structure and the second coupling structure, affects the phase shift.

[0064] The above embodiments relate to high-frequency power dividers. However, the same structure is used as a high-frequency power combiner circuit to obtain an output signal based on input signals from two or more signal input ports. For example, the combiner circuit includes: a squirrel-loop coupler configured to provide an output signal at the output port (e.g., P1) of the squirrel-loop coupler based on a signal at a first input of the squirrel-loop coupler (e.g., the position where TL7B is connected to the squirrel-loop coupler loop) and a signal at a second input of the squirrel-loop coupler (e.g., the position where TL8B is connected to the squirrel-loop coupler loop); a first coupling structure, TL7B, coupled to the first input of the squirrel-loop coupler to couple the first input of the squirrel-loop coupler to a first signal input port P2; and a second coupling structure, for example configured by TL8B, TL5B, and TL6B, coupled to the second input of the squirrel-loop coupler to couple the second input of the squirrel-loop coupler to a second signal input port P3; wherein the characteristic impedance (e.g., Z0 = 1 / K) of the first transmission line portion TL1B between the output port P1 and the first input of the squirrel-loop coupler... GB*sqrt(2)*R0) deviates from the nominal ring impedance (e.g., sqrt(2)*R0) of the mouse-ring coupler in the first direction, for example, less than the nominal ring impedance, and wherein the characteristic impedance (e.g., Z0 = K) of the second transmission line portion TL2B between the output port P1 and the second input of the mouse-ring coupler is... GB The *sqrt(2)*R0) deviates from the nominal toroidal impedance (e.g., sqrt(2)*R0) of the mouse-loop coupler in a second direction, which is opposite to the first direction and, for example, greater than the nominal toroidal impedance.

[0065] As another example of a high-frequency power combiner circuit for obtaining an output signal based on input signals from two or more signal input ports, the combiner circuit includes: a squirrel-coil coupler configured to provide an output signal at an output port (e.g., P1) of the squirrel-coil coupler based on signals at a first input of the squirrel-coil coupler (e.g., the location where TL7B is connected to the squirrel-coil coupler loop) and based on signals at a second input of the squirrel-coil coupler (e.g., the location where TL8B is connected to the squirrel-coil coupler loop); a first coupling structure, TL7B, coupled to the first input of the squirrel-coil coupler to couple the first input of the squirrel-coil coupler to a first signal input port P2; and A second coupling structure, configured, for example, by TL8B, TL5B, or TL6B, is coupled to the second input of the mouse-coil coupler to couple the second input of the mouse-coil coupler to the second signal input port P3; wherein the first and second coupling structures are adapted to provide different phase shifts with frequency; wherein the first coupling structure includes a phase shifter adapted to at least partially compensate for the difference between the frequency variation from the first input to the output port of the mouse-coil coupler and the frequency variation of the transmission characteristics from the second input to the output port of the mouse-coil coupler in an environment at the design frequency of the mouse-coil coupler, such frequency variations affecting, for example, the combination of signals at the first and second inputs of the mouse-coil coupler.

Claims

1. A high-frequency power divider circuit for distributing an input signal to two or more signal output ports, characterized in that, The high-frequency power divider circuit includes: A rat-loop coupler, wherein the rat-loop coupler is configured to couple an input signal provided at the input port of the rat-loop coupler to a first output of the rat-loop coupler and to a second output of the rat-loop coupler; A first coupling structure is coupled to the first output of the rat-loop coupler to couple the first output of the rat-loop coupler to the first signal output port; and A second coupling structure is coupled to the second output of the rat-coil coupler to couple the second output of the rat-coil coupler to the second signal output port; Wherein, the characteristic impedance value of the first transmission line section between the input port and the first output of the mouse-coil coupler deviates from the nominal ring impedance value of the mouse-coil coupler in a first direction, and Specifically, the characteristic impedance of the second transmission line section between the input port and the second output of the mouse-coil coupler deviates from the nominal ring impedance of the mouse-coil coupler in a second direction, which is opposite to the first direction. The first direction and the second direction represent the direction of deviation of the characteristic impedance value from the nominal toroidal impedance value.

2. The high-frequency power divider circuit according to claim 1, wherein, The characteristic impedance of the third transmission line portion between the second output of the rat-loop coupler and the other port of the rat-loop coupler deviates from the nominal ring impedance in the same direction as the characteristic impedance of the first transmission line portion.

3. The high-frequency power divider circuit according to claim 2, wherein, The characteristic impedance of the fourth transmission line portion between the first output of the rat-loop coupler and the other port of the rat-loop coupler deviates from the nominal ring impedance in the same direction as the characteristic impedance of the second transmission line portion.

4. The high-frequency power divider circuit according to claim 3, wherein, The characteristic impedance value of the first transmission line section differs from the characteristic impedance value of the third transmission line section by no more than ±25% of the characteristic impedance of the first transmission line section and the characteristic impedance of the second transmission line section.

5. The high-frequency power divider circuit according to claim 3, wherein, The characteristic impedance value of the first transmission line section differs from the characteristic impedance value of the third transmission line section by no more than ±10% of the characteristic impedance of the first transmission line section and the characteristic impedance of the second transmission line section.

6. The high-frequency power divider circuit according to claim 4, wherein, The characteristic impedance value of the second transmission line section differs from the characteristic impedance value of the fourth transmission line section by no more than ±25% of the characteristic impedance of the second transmission line section and the characteristic impedance of the first transmission line section.

7. The high-frequency power divider circuit according to claim 4, wherein, The characteristic impedance value of the second transmission line section differs from the characteristic impedance value of the fourth transmission line section by no more than ±10% of the characteristic impedance of the second transmission line section and the characteristic impedance of the first transmission line section.

8. The high-frequency power divider circuit according to claim 6, wherein, The product of the characteristic impedance of the first transmission line section or the characteristic impedance of the third transmission line section and the characteristic impedance of the second transmission line section or the characteristic impedance of the fourth transmission line section is equal to the square of the nominal ring impedance, with a tolerance of ±10%.

9. The high-frequency power divider circuit according to claim 8, wherein, The characteristic impedance of the first transmission line section or the characteristic impedance of the third transmission line section is less than the characteristic impedance of the second transmission line section or the characteristic impedance of the fourth transmission line section.

10. The high-frequency power divider circuit according to claim 1 or 2, wherein, The deviation of the characteristic impedance from the nominal toroidal impedance is within ±20% of the value of the nominal toroidal impedance.

11. The high-frequency power divider circuit according to claim 1 or 2, wherein, The deviation of the characteristic impedance from the nominal toroidal impedance is within ±10% of the value of the nominal toroidal impedance.

12. The high-frequency power divider circuit according to claim 8, wherein, The characteristic impedance values ​​of the first transmission line portion and the third transmission line portion deviate from the nominal ring impedance value by +1% to +20%, and the characteristic impedance values ​​of the second transmission line portion and the fourth transmission line portion deviate from the nominal ring impedance value by -1% to -20%.

13. The high-frequency power divider circuit according to claim 8, wherein, The characteristic impedance values ​​of the first transmission line portion and the third transmission line portion deviate from the nominal ring impedance value by +1% to +10%, and the characteristic impedance values ​​of the second transmission line portion and the fourth transmission line portion deviate from the nominal ring impedance value by -1% to -10%.

14. A high-frequency power divider circuit for distributing an input signal to two or more signal output ports, characterized in that, The high-frequency power divider circuit includes: A rat-loop coupler, wherein the rat-loop coupler is configured to couple an input signal provided at the input port of the rat-loop coupler to a first output of the rat-loop coupler and to a second output of the rat-loop coupler; A first coupling structure is coupled to the first output of the rat-loop coupler to couple the first output of the rat-loop coupler to the first signal output port; and A second coupling structure is coupled to the second output of the rat-coil coupler to couple the second output of the rat-coil coupler to the second signal output port; The first coupling structure and the second coupling structure are adapted to provide different phase shifts with frequency; The first coupling structure includes a phase shifter adapted to at least partially compensate for frequency variations in the phase difference between the signals at the first output and the second output of the rat-coil coupler in an environment at the design frequency of the rat-coil coupler.

15. The high-frequency power divider circuit according to claim 14, wherein, The second coupling structure includes a pair of coupled transmission lines and another transmission line, wherein the pair of coupled transmission lines includes a first coupled transmission line and a second coupled transmission line. The first end of the first coupling transmission line is connected to the second output of the mouse-loop coupler. Wherein, the second end of the first coupled transmission line is connected to the second end of the second coupled transmission line, and the second end of the second coupled transmission line is adjacent to the second end of the first coupled transmission line, and The first end of the second coupling transmission line is connected to the second signal output port, or constitutes the second signal output port.

16. The high-frequency power divider circuit according to claim 15, wherein, The first end of the first coupling transmission line is connected to the second output of the mouse-ring coupler via the other transmission line.

17. The high-frequency power divider circuit according to claim 15 or 16, wherein, The characteristic impedance of the other transmission line deviates from the reference impedance by no more than ±5%.

18. The high-frequency power divider circuit according to claim 15 or 16, wherein, The characteristic impedance of the other transmission line deviates from the reference impedance by no more than ±10%.

19. The high-frequency power divider circuit according to claim 15 or 16, wherein, The product of the even-mode impedance and the odd-mode impedance of the pair of coupled transmission lines deviates from the square of the reference impedance by no more than ±5%.

20. The high-frequency power divider circuit according to claim 15 or 16, wherein, The product of the even-mode impedance and the odd-mode impedance of the pair of coupled transmission lines deviates from the square of the reference impedance by no more than ±10%.

21. The high-frequency power divider circuit according to claim 15 or 16, wherein, The product of the even-mode impedance and the odd-mode impedance of the pair of coupled transmission lines deviates from the square of the reference impedance by no more than ±15%.

22. The high-frequency power divider circuit according to claim 15 or 16, wherein, The electrical length of the pair of coupled transmission lines deviates from one-quarter of the wavelength of the rat-ring coupler at the design center frequency by no more than ±5%.

23. The high-frequency power divider circuit according to claim 15 or 16, wherein, The electrical length of the pair of coupled transmission lines deviates from one-quarter of the wavelength of the rat-ring coupler at the design center frequency by no more than ±10%.

24. The high-frequency power divider circuit according to claim 15 or 16, wherein, The length of the other transmission line is selected to decouple the stray field of the pair of coupled transmission lines from the mouse-loop coupler.

25. The high-frequency power divider circuit according to claim 15 or 16, wherein, The electrical length of the transmission line forming the first coupling structure is equal to the electrical length of the other transmission line plus half a wavelength, with a tolerance of ± one-tenth of the wavelength.

26. A high-frequency power combiner circuit for obtaining an output signal based on input signals from two or more signal input ports, characterized in that, The high-frequency power combiner circuit includes: A rat-loop coupler, wherein the rat-loop coupler is configured to provide an output signal at the output port of the rat-loop coupler based on a signal at a first input of the rat-loop coupler and a signal at a second input of the rat-loop coupler; A first coupling structure is coupled to the first input of the rat-loop coupler to couple the first input of the rat-loop coupler to the first signal input port; and A second coupling structure is coupled to the second input of the rat-coil coupler to couple the second input of the rat-coil coupler to the second signal input port; Wherein, the characteristic impedance of the first transmission line section between the output port and the first input of the squirrel-loop coupler deviates from the nominal ring impedance of the squirrel-loop coupler in a first direction, and Specifically, the characteristic impedance of the second transmission line section between the output port and the second input of the mouse-loop coupler deviates from the nominal ring impedance of the mouse-loop coupler in a second direction, which is opposite to the first direction. The first direction and the second direction represent the direction of deviation of the characteristic impedance value from the nominal toroidal impedance value.

27. A high-frequency power combiner circuit for obtaining an output signal based on input signals from two or more signal input ports, characterized in that, The high-frequency power combiner circuit includes: A rat-loop coupler, wherein the rat-loop coupler is configured to provide an output signal at the output port of the rat-loop coupler based on a signal at a first input of the rat-loop coupler and a signal at a second input of the rat-loop coupler; A first coupling structure is coupled to the first input of the rat-loop coupler to couple the first input of the rat-loop coupler to the first signal input port; and A second coupling structure is coupled to the second input of the rat-coil coupler to couple the second input of the rat-coil coupler to the second signal input port; The first coupling structure and the second coupling structure are adapted to provide different phase shifts with frequency; The first coupling structure includes a phase shifter adapted to at least partially compensate for the difference between the frequency variation from the first input of the rat-coil coupler to the output port and the frequency variation of the transmission characteristics from the second input of the rat-coil coupler to the output port in an environment at the design frequency of the rat-coil coupler.

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