A lumped 90° phase difference filter power dividing device

Abstract

This invention discloses a lumped 90° phase difference filtering power distribution device, belonging to the field of microwave technology. The invention employs a centrally symmetrical integrated structure constructed with fully lumped-parameter components, including four ports, a ring-shaped symmetrical inductor circuit, a cross-shaped symmetrical capacitor circuit, and two sets of trapezoidal symmetrical LC circuits. The ring-shaped symmetrical inductor circuit and the cross-shaped symmetrical capacitor circuit are connected via an embedded interconnection, and the two sets of trapezoidal symmetrical LC circuits are connected in parallel with the former two, one above the other. This invention regulates the output phase difference through the ring-shaped symmetrical inductor circuit and controls the power distribution ratio through the trapezoidal symmetrical LC circuits. These three components work together to form multiple transmission zeros to achieve filtering functionality, simultaneously realizing 90° quadrature phase output, unequal power distribution, and filtering response. It possesses advantages such as compact structure, miniaturization, high integration, and low insertion loss.

Description

Technical Field

[0001] This invention relates to the field of microwave technology, and in particular to a lumped 90° phase difference filter power distribution device. Background Technology

[0002] Lumped power distribution devices use lumped-parameter components such as resistors, inductors, and capacitors to form a matching and distribution network, distributing the input signal into two or more outputs according to a set ratio. They offer advantages such as small size, compact structure, and low cost, and are primarily suitable for low- to mid-frequency RF and microwave systems. They are key passive devices for signal power distribution in RF and microwave circuits. Integrating filtering functionality into lumped power distribution devices can further reduce circuit size, increase integration density, and reduce overall losses at the system level. Simultaneously, outputting signals with a 90° phase difference enhances the orthogonality of the output signals, improves system anti-interference capability and signal stability, and eliminates the need for additional phase-shifting networks in systems requiring a 90° phase difference, thereby simplifying the system structure, reducing insertion loss, and lowering design complexity. Therefore, it is necessary to invent a lumped 90° phase-difference filtering power distribution device.

[0003] Existing power distribution filtering devices are mainly designed with distributed parameters, and their implementation methods are mainly of two types: The first type adopts a three-stage branch line structure, adding a short-circuit point on the first-stage λ / 2 transmission line and loading a short-circuit stub on the second-stage branch line to achieve unequal filtering output at two ports. However, it suffers from the problem of large circuit size and a phase difference of 180°, which is not suitable for scenarios requiring a phase difference of 90°. The second type uses two adjacent single-mode substrate integrated waveguide resonators for filtering and arranges two microstrip lines above the resonators to achieve power distribution. However, due to the large size of the substrate integrated waveguide resonators, it is not conducive to further miniaturization of the device, and the output phase is in phase but does not satisfy orthogonality. Therefore, an additional phase compensation circuit is required to achieve the required phase relationship. The lumped-type implementation method mainly uses three pairs of LC series resonators and one pair of LC parallel resonators to introduce four transmission zeros outside the passband, and adds an RLC series structure between the two output ports for isolation. Although it achieves the advantages of miniaturization, low loss and self-packaging, it is difficult to adapt to application scenarios with unequal power distribution, and the output signal phase is in phase but not orthogonal, requiring additional phase compensation circuit.

[0004] In summary, it is necessary to propose a lumped 90° phase difference filter power distribution device that can take into account 90° output phase difference, unequal power output and filtering function, and has the characteristics of small size and easy integration. Summary of the Invention

[0005] Purpose of the invention: In view of the above-mentioned prior art, a lumped 90° phase difference filter power distribution device is proposed, which can simultaneously realize 90° output phase difference, unequal power output, filtering function and small size and easy integration.

[0006] Technical solution: A lumped 90° phase difference filter power distribution device includes four ports, a ring symmetrical inductor circuit, a cross symmetrical capacitor circuit, a first trapezoidal symmetrical LC circuit, and a second trapezoidal symmetrical LC circuit; the ring symmetrical inductor circuit and the cross symmetrical capacitor circuit are connected by an embedded interconnection method, and the first trapezoidal symmetrical LC circuit and the second trapezoidal symmetrical LC circuit are respectively connected in parallel with the ring symmetrical inductor circuit and the cross symmetrical capacitor circuit on the upper and lower outer sides; the device as a whole has a centrally symmetrical structure.

[0007] Furthermore, the ring-shaped symmetrical inductor circuit consists of eight inductors connected in series to form a closed loop, with each pair of inductors forming one side of the loop; wherein, the first inductor and the second inductor are connected in series between the first port and the fourth port, the third inductor and the fourth inductor are connected in series between the second port and the third port, the fifth inductor and the sixth inductor are connected in series between the first port and the second port, and the seventh inductor and the eighth inductor are connected in series between the third port and the fourth port.

[0008] Furthermore, the cross-shaped symmetrical capacitor circuit is composed of four grounded capacitors that are grounded together; wherein, the first grounded capacitor is connected in parallel at the interval between the fifth and sixth inductors, the second grounded capacitor is connected in parallel at the interval between the seventh and eighth inductors, the third grounded capacitor is connected in parallel at the interval between the first and second inductors, and the fourth grounded capacitor is connected in parallel at the interval between the third and fourth inductors.

[0009] Furthermore, the first trapezoidal symmetrical LC circuit and the second trapezoidal symmetrical LC circuit have the same structure, both consisting of four series inductors and three spaced parallel grounded capacitors.

[0010] Furthermore, by adjusting the parameters of the first, second, third, and fourth inductors, a 90° phase difference can be generated between the two output signals of the device; by reducing the values ​​of the first and second inductors, or by reducing the values ​​of the third and fourth inductors, the phase difference between the output signals at the two ports can be increased.

[0011] Furthermore, by reducing the inductance of the first trapezoidal symmetrical LC circuit and the second trapezoidal symmetrical LC circuit, while increasing their capacitance, the power distribution ratio of the device can be improved.

[0012] Furthermore, the first trapezoidal symmetrical LC circuit, the second trapezoidal symmetrical LC circuit, the ring symmetrical inductor circuit, and the cross symmetrical capacitor circuit work together to form a transmission zero point to achieve the filtering response.

[0013] Furthermore, when the signal is input from the first port, the second port is an isolation port, and the third and fourth ports are output ports; the isolation port forms three isolation poles, and each of the two output ports forms two transmission zeros, so as to improve the out-of-band rejection and frequency selectivity of the device.

[0014] Furthermore, the center frequency of the device is jointly controlled by the inductance parameters of the ring symmetrical inductor circuit and the capacitance parameters of the cross symmetrical capacitor circuit.

[0015] Beneficial effects: This invention integrates a ring-shaped symmetrical inductor circuit, a cross-shaped symmetrical capacitor circuit, and a pair of trapezoidal symmetrical LC circuits using embedded interconnection and parallel connection on the upper and lower sides, respectively. It utilizes the components of the symmetrical trapezoidal LC circuit to control the power distribution ratio, and works in conjunction with the inductance of the ring-shaped symmetrical inductor circuit and the capacitance of the cross-shaped symmetrical capacitor circuit to control the transmission zero point. Combined with the control of the output phase difference by the inductance of the ring-shaped symmetrical inductor circuit, a lumped 90° phase difference filtering power distribution device is realized. It has the advantages of being able to take into account unequal power output, filtering response, quadrature phase output, as well as circuit miniaturization and compact structure.

[0016] Specifically, the ring symmetrical inductor circuit consists of eight inductors connected in series, with each pair of inductors forming one side. It is also connected to a cross-shaped symmetrical capacitor circuit composed of four grounded capacitors in an embedded interconnect manner. The component parameters can control the center frequency of the device and, in combination with the component parameters of the trapezoidal symmetrical LC circuit, control the transmission zero point. At the same time, the inductance parameters of the ring symmetrical inductor circuit itself can control the output phase difference.

[0017] The trapezoidal symmetrical LC circuit consists of four series inductors combined with three spaced parallel grounded capacitors. Its component values ​​can control the power distribution ratio, and it can be combined with the toroidal symmetrical inductor circuit and the cross-shaped symmetrical capacitor circuit to realize and control the transmission zero point, thereby enabling the device to have a filtering response. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the circuit structure of the lumped 90° phase difference filter power distribution device of the present invention; Figure 2 This is a simulation diagram of the input-isolation port S-parameter curve of the device in an embodiment of the present invention; Figure 3 This is a simulation diagram of the input-output port S-parameter curves of the device in an embodiment of the present invention; Figure 4 The output phase simulation results are shown for the device in the embodiment of the present invention. Detailed Implementation

[0019] The invention will now be further explained with reference to the accompanying drawings.

[0020] A lumped 90° phase difference filter power distribution device, such as Figure 1 As shown, it consists of four ports (port one to port four), a ring-shaped symmetrical inductor circuit A, a cross-shaped symmetrical capacitor circuit B, a trapezoidal symmetrical LC circuit C, and a trapezoidal symmetrical LC circuit D.

[0021] The toroidal symmetrical inductor circuit A consists of eight inductors connected in series, where inductor L... 101 Inductor L 102 Inductor L is connected in series between port 1 and port 4. 103 Inductor L 104 Inductor L is connected in series between port 2 and port 3. 105 Inductor L 106 Inductor L is connected in series between port 1 and port 2. 107 Inductor L 108 It is connected in series between port 3 and port 4.

[0022] The cross-shaped symmetrical capacitor circuit B consists of four grounded capacitors that share a common ground, among which the grounded capacitor C... 201 Parallel to inductor L 105 With inductor L 106 At the interval, the grounding capacitor C 202 Parallel to inductor L 107 With inductor L 108 At the interval, the grounding capacitor C 203 Parallel to inductor L 101 With inductor L 102 At the interval, the grounding capacitor C 204 Parallel to inductor L 103 With inductor L 104 Intervals.

[0023] The trapezoidal symmetrical LC circuit C consists of four inductors and three capacitors, where the inductors L 301 Inductor L 302 Inductor L 303 With inductor L 304 They are connected in series sequentially, and capacitors C are connected in parallel at different intervals between the inductors to ground. 305 Grounding capacitor C 306 With grounding capacitor C 307 .

[0024] The trapezoidal symmetrical LC circuit D consists of four inductors and three capacitors, where the inductors L 401 Inductor L 402 Inductor L 403 With inductor L 404 They are connected in series sequentially, and capacitors C are connected in parallel at different intervals between the inductors to ground. 405 Grounding capacitor C 406 With grounding capacitor C 407 .

[0025] The overall structure of the device of this invention is centrally symmetrical, and the performance obtained by the signal input from any port is the same. When the signal is input from port one, it flows through the ring symmetrical inductor circuit A, the cross symmetrical capacitor circuit B, the trapezoidal symmetrical LC circuit C, and the trapezoidal symmetrical LC circuit D, and is finally output from port four and port three. Port two is an isolation port. Under the synergistic effect of the overall circuit, it constitutes a lumped filter power distribution device with a 90° phase difference output.

[0026] During this process, the signal is input from port one, and the isolation channel corresponding to port two generates three isolation poles. The isolation poles on the left and right sides are formed by the trapezoidal symmetrical LC circuit C, the trapezoidal symmetrical LC circuit D, and the inductor L. 105 Inductor L 106 Inductor L 107 Inductor L 108 and grounding capacitor C 201 Grounding capacitor C 202 The isolation poles in the middle are provided by a ring-shaped symmetrical inductor circuit A and a cross-shaped symmetrical capacitor circuit B. The output channel containing port three can generate two transmission zeros, thereby improving the frequency selectivity of the channel and achieving a filtering function. The transmission zeros are formed by the trapezoidal symmetrical LC circuit C, the trapezoidal symmetrical LC circuit D, and the inductor L... 105 Inductor L 106 Inductor L 107 Inductor L 108 With grounding capacitor C 201 Grounding capacitor C 202 The resulting LC reactance network exhibits pure reactance characteristics at the corresponding frequency, thus generating transmission zeros. The output channel containing port four generates two transmission zeros to improve the out-of-band rejection of this channel. The two transmission zeros originate from the overall signal phase reversal generated by the ring symmetrical inductor circuit A, the cross symmetrical capacitor circuit B, the trapezoidal symmetrical LC circuit C, and the trapezoidal symmetrical LC circuit D, thereby forming transmission zeros.

[0027] In the circuit, the combination of decreasing inductance and increasing capacitance in trapezoidal symmetrical LC circuits C and D can improve the power distribution ratio. Furthermore, by appropriately configuring the inductor L in the toroidal symmetrical inductor circuit A... 101 Inductor L 102 Inductor L 103 Inductor L 104 This allows the two input signals to have a 90° phase difference under the overall effect, specifically by reducing the inductance L in the ring symmetrical inductor circuit A. 101 Inductor L 102 The value, or reduce the inductance L 103 Inductor L 104The value of can increase the phase difference between the output signals of the two ports within a certain range.

[0028] In summary, this invention uses fully lumped parameter components to construct a centrally symmetrical integrated circuit. Through the synergy of various sub-circuits, multiple isolation poles and transmission zeros are formed to achieve out-of-band suppression. At the same time, it achieves 90° phase difference regulation and unequal power distribution, integrating filtering, phase difference output, and power distribution functions. The lumped structure is compact and has both high integration and practicality.

[0029] In this implementation, the device parameters are as follows: L 101 = L 102 = L 103 = L 104 = 17.91 nH, L 105 = L 106 =L 107 = L 108 = 13.98 nH, C 201 = C 202 = 11.37 pF, C 203 = C 204 = 8.84 pF, L 301 = L 304 = L 401 =L 404 = 21.09 nH, L 302 = L 303 = L 402 = L 403 = 42.18 nH, C 305 = C 306 =C 307 = C 405 = C 406 = C 407 =7.51 pF. When the signal is input from port one, the simulated S-parameter response and simulated output phase response of the device are as follows: Figures 2 to 4 As shown. By Figure 2 , Figure 3 The S-parameter response shows that the center frequency of this example is designed to be 400 MHz, and the output power ratio of port 4 to port 3 is 4.4. Specifically, the 3-dB operating frequency range of the output channel containing port 4 is 340 MHz to 451 MHz, and the 3-dB operating frequency range of the output channel containing port 3 is 359 MHz to 440 MHz. The isolation bandwidth of the device covers the range of 307 MHz to 502 MHz, with a minimum isolation of 10.73 dB. At the center frequency, the theoretical insertion losses of the two output channels are 0.04 dB and 0.16 dB, respectively. Furthermore, from... Figure 4The phase response confirms that the phase difference between the two output ports is 90° at the center frequency.

[0030] Compared with existing technologies, the present invention can simultaneously take into account the characteristics of 90° output phase difference, unequal power output, filtering function and small size and easy integration.

[0031] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A lumped 90° phase difference filter power distribution device, characterized in that, It includes four ports, a ring-shaped symmetrical inductor circuit, a cross-shaped symmetrical capacitor circuit, a first trapezoidal symmetrical LC circuit, and a second trapezoidal symmetrical LC circuit; the ring-shaped symmetrical inductor circuit and the cross-shaped symmetrical capacitor circuit are connected by an embedded interconnection method, and the first trapezoidal symmetrical LC circuit and the second trapezoidal symmetrical LC circuit are respectively arranged in parallel with the ring-shaped symmetrical inductor circuit and the cross-shaped symmetrical capacitor circuit on the upper and lower outer sides; the device as a whole has a centrally symmetrical structure.

2. The lumped 90° phase difference filter power distribution device according to claim 1, characterized in that, The ring-shaped symmetrical inductor circuit consists of eight inductors connected in series to form a closed loop, with each pair of inductors forming one side of the loop; wherein, the first inductor and the second inductor are connected in series between the first port and the fourth port, the third inductor and the fourth inductor are connected in series between the second port and the third port, the fifth inductor and the sixth inductor are connected in series between the first port and the second port, and the seventh inductor and the eighth inductor are connected in series between the third port and the fourth port.

3. The lumped 90° phase difference filter power distribution device according to claim 2, characterized in that, The cross-shaped symmetrical capacitor circuit is composed of four grounded capacitors that are grounded together; wherein, the first grounded capacitor is connected in parallel at the interval between the fifth and sixth inductors, the second grounded capacitor is connected in parallel at the interval between the seventh and eighth inductors, the third grounded capacitor is connected in parallel at the interval between the first and second inductors, and the fourth grounded capacitor is connected in parallel at the interval between the third and fourth inductors.

4. The lumped 90° phase difference filter power distribution device according to claim 1, characterized in that, The first trapezoidal symmetrical LC circuit and the second trapezoidal symmetrical LC circuit have the same structure, both consisting of four series inductors and three spaced parallel grounded capacitors.

5. The lumped 90° phase difference filter power distribution device according to claim 2, characterized in that, By adjusting the parameters of the first, second, third, and fourth inductors, a 90° phase difference can be generated between the two output signals of the device; by reducing the values ​​of the first and second inductors, or by reducing the values ​​of the third and fourth inductors, the phase difference between the output signals at the two ports can be increased.

6. The lumped 90° phase difference filter power distribution device according to claim 4, characterized in that, By reducing the inductance of the first trapezoidal symmetrical LC circuit and the second trapezoidal symmetrical LC circuit, while increasing their capacitance, the power distribution ratio of the device can be improved.

7. The lumped 90° phase difference filter power distribution device according to claim 5, characterized in that, The first trapezoidal symmetrical LC circuit, the second trapezoidal symmetrical LC circuit, the ring symmetrical inductor circuit, and the cross symmetrical capacitor circuit work together to form a transmission zero point to achieve the filtering response.

8. The lumped 90° phase difference filter power distribution device according to claim 1, characterized in that, When a signal is input from the first port, the second port is an isolation port, and the third and fourth ports are output ports. The isolation port forms three isolation poles, and each of the two output ports forms two transmission zeros to improve the out-of-band rejection and frequency selectivity of the device.

9. The lumped 90° phase difference filter power distribution device according to claim 1, characterized in that, The center frequency of the device is jointly controlled by the inductance parameters of the ring symmetrical inductor circuit and the capacitance parameters of the cross symmetrical capacitor circuit.

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