CN203932267U - Coaxial harmonic connector - Google Patents

Abstract

The utility model discloses a coaxial harmonic filter connector, which comprises a shell, and a harmonic filter is arranged inside the shell, and the two ends of the harmonic filter are respectively connected with an input joint and an output joint; the series inductor in the harmonic filter and parallel capacitors are replaced by coaxial high-impedance lines and low-impedance lines respectively; the input connector is an input connector of a microstrip coaxial connector. The utility model integrates the RF output connector of the power amplifier, the filter for suppressing the harmonic output, and the power output connector of the transmitter, and realizes the connection of a plurality of single-function microwave devices. The harmonic output of the transmitter meets higher technical index requirements, and the circuit is simplified, the volume is reduced, the power loss and economic cost are reduced, and the applicability and reliability of the equipment are further improved.

Description

Coaxial Harmonic Filter Connector

technical field

The utility model belongs to the technical field of microwave communication, in particular to a coaxial harmonic filter connector.

Background technique

Harmonic output is an important technical index of the transmitter. As the power signal output device of the electronic system, the transmitter often has some useless or harmful power components in the output power signal, in addition to the required useful signal power, and the harmonic output is the most typical part of it. .

The existing coaxial harmonic filter device has complex circuits and a huge structure, and requires wires to be installed at the output end of the power amplifier. The overall filtering and stability performance cannot meet the requirements, and the installation is inconvenient.

Utility model content

The purpose of this utility model is to provide a coaxial harmonic filter connector, which can realize the integration of multiple single-function microwave devices, has simple circuit, compact structure, convenient installation, reduces insertion loss, and improves the overall reliability of the equipment. .

The utility model adopts the following technical solutions:

The coaxial harmonic filter connector includes a shell, and a harmonic filter is arranged in the shell, and the two ends of the harmonic filter are respectively connected with an input joint and an output joint; the series inductor and the parallel capacitor in the harmonic filter are respectively used Coaxial high-impedance and low-impedance lines instead.

The input connector is an input connector of a microstrip coaxial connector.

The output connector adopts the output connector of a standard N-type radio frequency coaxial connector.

The shell adopts a common structural shell of a common N-type KFK connector.

The harmonic filter is a low-pass prototype filter.

The utility model has a simple structure. It integrates and innovates the RF output connector of the power amplifier, the filter for suppressing harmonic output, and the power output connector of the transmitter, and realizes the connection of multiple single-function microwave devices. Together, the harmonic output of the transmitter meets the higher technical index requirements, and the circuit is simplified, the volume is reduced, the power loss and economic cost are reduced, and the applicability and reliability of the equipment are further improved.

Description of drawings

Fig. 1 a is the schematic diagram of the small section of the transmission line in the harmonic filter described in the present invention;

Fig. 1 b is the schematic diagram of the T-shaped equivalent circuit of transmission line segment in the harmonic filter described in the utility model;

Fig. 1c is the schematic diagram of the equivalent circuit of transmission line segment П type in the harmonic filter described in the utility model;

Fig. 2 is a model diagram of the coaxial harmonic filter circuit described in the utility model;

Fig. 3 is a schematic view of the structure of the utility model;

Fig. 4 is the simulation diagram of the stop band suppression characteristic of the present utility model;

Fig. 5 is a simulation diagram of passband attenuation and port standing wave of the present invention.

Detailed ways

As shown in Figure 3, the coaxial harmonic filter connector includes a shell 2, and a harmonic filter is arranged in the shell 2, and the two ends of the harmonic filter are respectively connected to an input joint 3 and an output joint 1; The series inductance and parallel capacitance in the filter are replaced by coaxial high-impedance lines and low-impedance lines respectively, thus forming a low-pass prototype filter, thereby realizing harmonic filtering.

The low-pass prototype filter is composed of a series of series inductors and parallel capacitors connected alternately. In microwave circuits, a small section of transmission line can be equivalent to a T-shaped or П-shaped network composed of capacitors and inductors; in Figure 1a-Figure 1c, I represents the length of the small segment of the transmission line, and _Z0 and _Y0 are its impedance and admittance. In the T-type equivalent circuit, its equivalent reactance X and susceptance are B respectively:

In the П-type equivalent circuit, its equivalent reactance X and susceptance B are: (3)

The approximate equivalent requirement of the above formula . When the transmission line is short and properly terminated, it can be approximated as equivalent to a single reactive element. For a small section of low-impedance transmission line with high-impedance lines connected at both ends, the series reactance X in its T-shaped equivalent circuit is very small, while the reactance of the high-impedance lines connected in series at both ends is very large, so X can be ignored , so it can be equivalent to a single parallel capacitor. Similarly, for a small section of high-impedance transmission line with low-impedance lines connected at both ends, the parallel susceptance B in its П-type equivalent circuit is very small, while the susceptance of the low-impedance line connected at both ends is very large , so B can also be ignored, so its circuit can be equivalent to a single series inductor.

The relationship between the characteristic impedance Z0 of the coaxial line and the outer diameter a of the inner conductor and the inner diameter b of the outer conductor is: (Ohm) (5) where: and are the relative permittivity and relative permeability of the filling medium between the two conductors of the coaxial line, respectively.

If the series inductance and parallel capacitance in the filter element are realized by coaxial high-impedance lines and low-impedance lines respectively, then both the series inductance and parallel capacitance will be related to the impedance value of the coaxial line and the length of the line segment, while the impedance is only related to the coaxial line. The size of the inner and outer conductors of the axis is related, and its length is related to the frequency. Considering the processing rationality of the structural design size and the transmission characteristics of conductor loss and average power, the selected high impedance is 100 ohms and the low impedance is 25 ohms in this embodiment; considering the maximum attenuation of the passband LAr≤0.3dB, the stopband The minimum attenuation LA≥40dB, the number of components is n=11, and the design model of the coaxial filter circuit is shown in Figure 2.

In terms of structural realization, the input connector 3 is designed in the form of a microstrip coaxial connector, and the output connector 1 is directly in the form of a standard N-type RF coaxial connector; in the design of the installation method, a general-purpose N-type KFK connector is used general structural form. The structural appearance of the entire harmonic filter connector is shown in Figure 3.

The input connector is the input connector 3 of the microstrip coaxial connector, the output connector 1 adopts the output connector 1 of the standard N-type radio frequency coaxial connector, and the shell adopts the universal N-type KFK connector general structure shell. The design of the coaxial harmonic filter connector is not only simple in circuit, compact in structure and easy to install, but also due to the ingenious integrated processing, the insertion loss of the original power cable when inserted into the port improves the port standing wave , and reduces cost, improves transmitter efficiency and equipment reliability.

As shown in Figure 4 and Figure 5: choose copper material and air medium, use Ansoft microwave simulation software to model, simulate and optimize the design of the filter connector circuit. By changing the length of the high and low impedance line segments and the structural parameter values of the coaxial connector, the passband attenuation and stopband suppression characteristics of the filter circuit are optimized and calculated, and the simulation results are obtained.

According to the needs of the project, the actual design of the harmonic filter connector has an overall size of 85mm×35mm×25mm, and the test results of its main technical indicators; it can be seen from the examples that, in addition to the frequency bandwidth, harmonic suppression, port standing wave In addition to being able to meet the requirements well, its insertion loss has improved by about 0.85dB compared with the previous one, which is equivalent to increasing the output power of the power amplifier by 17.8% under the same conditions.

Practice has proved that the design of this harmonic filter connector not only has a simple circuit, compact structure, and convenient installation, but also reduces insertion loss, improves port standing waves, and reduces cost, improved transmitter efficiency and equipment reliability.

Claims (5)

1. coaxial harmonic connector, comprises shell, is provided with harmonic filter in shell, it is characterized in that: the two ends of harmonic filter are connected with respectively input adapter and out splice going splice; In described harmonic filter, series inductance and shunt capacitance replace with coaxial high impedance line and low-impedance line respectively.

2. coaxial harmonic connector according to claim 1, is characterized in that: described input adapter is micro-input adapter with coaxial connector.

3. coaxial harmonic connector according to claim 1, is characterized in that: described out splice going splice adopts the out splice going splice of the N-type radio frequency (RF) coaxial connector of standard.

4. according to the coaxial harmonic connector described in the arbitrary claim of claim 1-3, it is characterized in that: described shell adopts the universal architecture shell of general N-type KFK connector.

5. coaxial harmonic connector according to claim 4, is characterized in that: described harmonic filter is lowpass prototype filter.