Improved medium-wave multi-order deploying network

Abstract

The utility model discloses an improved medium-wave multi-order deploying network, which belongs to an antenna deploying facility and comprises a first-order tuning unit and a second-order tuning unit. The first-order tuning unit comprises a first inductance coil and a second inductance coil which are connected in parallel and grounded, the second tuning unit comprises a third inductance coil and a fourth inductance coil, the first-order tuning unit and the second-order tuning unit are designed in the network, the broadcast frequency working bandwidth can be widened, and when the standing-wave ratio is smaller than or equal to 1.2, the frequency of the broadcast frequency can be increased. And the debugging bandwidth is 3 times of the bandwidth of the traditional inverted L-shaped, T-shaped or pi-shaped single-loop deploying network, and the broadcasting requirement of the future technical development of medium waves can be met.

Description

Technical Field

[0001] This utility model relates to an antenna tuning facility, and more specifically, it relates to an improved mid-wave multi-order tuning network. Background Technology

[0002] Rapid urbanization and the increasingly tight land supply and demand have spurred the upgrading and transformation of medium-wave antennas. Existing wire-operated medium-wave antennas have been replaced by freestanding medium-wave antennas that are also becoming shorter and smaller. This necessitates the use of single-loop matching networks ("Г", "T", or "П") in the low-frequency band (below 800kHz) of medium-wave, requiring a working bandwidth (B) of at least 9kHz with a VSWR of less than or equal to 1.2. However, in practice, such single-loop matching networks cannot meet the technical requirements for medium-wave broadcasting. Specific waveforms are shown below. Figure 1 As shown, it is necessary to conduct further research and improvement on the existing self-supporting medium-wave antenna structure. Utility Model Content

[0003] One of the objectives of this invention is to address the aforementioned shortcomings by providing an improved medium-wave multi-stage modulation network. This aims to solve the problem that existing single-loop modulation networks of the same type cannot meet the technical requirements for medium-wave broadcasting, such as a working bandwidth B of at least 9kHz.

[0004] To solve the above-mentioned technical problems, the present invention adopts the following technical solution:

[0005] This utility model provides an improved mid-wave multi-order tuning network, comprising a first-order tuning unit and a second-order tuning unit. The first-order tuning unit includes a first inductor and a second inductor connected in parallel and grounded. The first and second inductors are connected in series with a first capacitor, and in parallel with the second capacitor. The second capacitor is also grounded. The first inductor is also connected in parallel to a first network adjustment port, which is used to connect a mid-wave antenna. The mid-wave antenna is used to make its antenna impedance at the first network adjustment port close to the resistance of the second capacitor through impedance transformation. The second-order tuning unit includes a third inductor connected in parallel with a third capacitor. The third inductor and the third capacitor are also connected in series with a fourth capacitor, which is connected in series with the fourth inductor. The fourth inductor is connected to the transmitting end. The third inductor and the third capacitor are also connected to the first inductor through the second network adjustment port. The fourth inductor and the fourth capacitor are used to adjust the capacitive reactance to make the capacitive reactance value equal to the inductance value of the parallel resonant network of the third inductor and the third capacitor.

[0006] As a preferred embodiment, a further technical solution is: the second network adjustment port is used to superimpose the VSWR curve characteristics of the second-order tuning unit and the first-order tuning unit.

[0007] A further technical solution is that the third inductor and the third capacitor are connected in parallel with a resonant interval of 12 medium wave frequencies.

[0008] Compared with the prior art, the beneficial effects of this utility model are: by designing a first-order tuning unit and a second-order tuning unit in the network, the operating bandwidth of the broadcast frequency can be broadened. When the VSWR is ≤1.2, the tuning bandwidth is 3 times that of traditional single-loop tuning networks such as "Γ", "T" or "π", which can meet the broadcast needs of future medium wave technology development. Attached Figure Description

[0009] Figure 1 The VSWR (Standing Wave Ratio) graph of an existing self-standing medium-wave antenna is shown.

[0010] Figure 2 This is a schematic diagram illustrating a network structure of one embodiment of the present invention.

[0011] Figure 3 This is a first standing wave ratio (SWR) pattern used to illustrate an embodiment of the present invention.

[0012] Figure 4 This is a second standing wave ratio (SWR) pattern used to illustrate one embodiment of the present invention. Detailed Implementation

[0013] The present invention will be further described below with reference to the accompanying drawings.

[0014] refer to Figure 2As shown, one embodiment of this utility model is an improved medium-wave multi-order tuning network, which includes a first-order tuning unit and a second-order tuning unit. Specifically, the aforementioned first-order tuning unit includes a first inductor L1 and a second inductor L2 connected in parallel and grounded. The first inductor L1, the second inductor L2 and the first capacitor C1 are connected in series, and the first inductor L1, the second inductor L1 and the second capacitor C2 are connected in parallel. The aforementioned first inductor L1 is also connected in parallel to a first network adjustment port A, which is used to connect a medium-wave antenna. The medium-wave antenna is used to make its antenna impedance value at the first network adjustment port A close to the resistance value of the second capacitor C2 through impedance transformation. The aforementioned second-order tuning unit includes a third inductor L3, which is connected in parallel with a third capacitor C3. The third inductor L3 and the third capacitor C3 are also connected in series with a fourth capacitor C4, which is connected in series with the fourth inductor L4. The fourth inductor L4 is connected to the transmitting end. More importantly, the aforementioned third inductor L3 and the third capacitor C3 are also connected to a first inductor L1 through a second network adjustment port B. The fourth inductor L4 and the fourth capacitor C4 are used to adjust the capacitive reactance, making the capacitive reactance value equal to the inductance value of the parallel resonant network of the third inductor L3 and the third capacitor C3. Specifically, the aforementioned second network adjustment port B is used to superimpose the VSWR curve characteristics of the second-order tuning unit and the first-order tuning unit. Furthermore, the parallel resonant interval of the aforementioned third inductor and third capacitor has 12 medium-wave frequencies.

[0015] As Figure 2 As shown, the antenna impedance at point A is adjusted to R-jX through impedance transformation, where jX is close to the capacitance of the second capacitor C2. At this point, the antenna impedance at point A is equivalent to being in parallel with the first inductor L1, and the second inductor L2 is in parallel with the second capacitor C2. The first capacitor C1 is connected in series with both the first inductor L1 and the second inductor L2. By adjusting the spacing between the first and second inductors L1 and L2, adjusting the inductance of the first and second inductors L1 and L2, and adjusting the position of the center tap of the second inductor L2, the antenna impedance at point B is adjusted to 50±j0. At this point, the carrier frequency is fully resonant, and the VSWR is 1.2. The bandwidth is twice that of a single-loop modulation network such as a "Г" type, "T" type, or "П" type. The VSWR graph at this point is U-shaped, as shown in the diagram. Figure 3 As shown.

[0016] Furthermore, after point B, the second-order tuning occurs, with the third inductor L3 and the third capacitor C3 resonating in parallel at intervals of 12 medium-wave frequencies (12 × 9 kHz = 108 kHz; if the operating frequency is 720 kHz, then the resonant frequency of inductor L3 and capacitor C3 is 720 + 108 = 828 kHz). This frequency results in a high impedance through the parallel resonant network, exhibiting a large standing wave ratio (SWR) curve. As the SWR approaches the operating frequency, it flattens out. At this point, the SWR curve is superimposed on the characteristics of the first-order tuning SWR curve. The superimposed resonant SWR curve is close to an ideal rectangle, with the in-band SWR curve being maximized and flattened, and the out-of-band suppression being high. The SWR graph is M-shaped. When the operating frequency also becomes detuned through the parallel resonant network of the third coil inductor L3 and the third capacitor C3, the impedance becomes inductive. Therefore, the series resonant connection of the fourth capacitor C4 and the fourth coil inductor L4 is adjusted to become capacitive reactance. The capacitance value is adjusted to be equal to the inductive value of the parallel resonant network of the third coil inductor L3 and the third capacitor C3, so that the operating frequency and carrier frequency are fully resonant. When the VSWR is adjusted to 1.2, the bandwidth is approximately three times that of a single-loop modulation network such as a "Г" type, "T" type, or "П" type. Specifically... Figure 4 As shown.

[0017] As can be seen from the above embodiments of this utility model, the improved mid-wave multi-order modulation network provided by this utility model has significant advantages, specifically reflected in:

[0018] 1. It has good passband characteristics, low in-band insertion loss, and high transmission efficiency.

[0019] 2. It has good frequency selectivity and a resonance curve that is close to an ideal rectangle. It has high out-of-band suppression, which can effectively solve the problem of crosstalk between multiple antennas and multiple frequencies broadcast on the same station, reduce the need for blocking networks or notch networks between frequencies, and improve the broadcast efficiency of this frequency.

[0020] 3. It can broaden the operating bandwidth of the broadcast frequency. When the VSWR is ≤1.2, the debugging bandwidth is 3 times that of traditional single-loop modulation networks such as "Γ", "T" or "π", which can meet the broadcast needs of future medium wave technology development.

[0021] 4. Excellent lightning protection. Grounding the coils L1 and L2 allows lightning to conduct DC to the ground. Coupling capacitors C1 and C4 also block DC, effectively protecting the transmitter system.

[0022] In addition to the above, it should be noted that the terms "one embodiment," "another embodiment," and "embodiment" used in this specification refer to specific features, structures, or characteristics described in connection with that embodiment, which are included in at least one embodiment described in the general description of this application. The appearance of the same expression in multiple places in the specification does not necessarily refer to the same embodiment. Furthermore, when a specific feature, structure, or characteristic is described in connection with any embodiment, the intention is to suggest that implementing such a feature, structure, or characteristic in conjunction with other embodiments also falls within the scope of this utility model.

[0023] Although the present invention has been described herein with reference to several illustrative embodiments, it should be understood that many other modifications and implementations can be devised by those skilled in the art, which will fall within the scope and spirit of the principles disclosed herein. More specifically, various variations and modifications can be made to the components and / or layout of the subject matter combination within the scope of the disclosure, drawings, and claims. Besides variations and modifications to the components and / or layout, other uses will be apparent to those skilled in the art.

Claims

1. An improved multi-order matching network for a medium wave, characterized by: Includes a first-order tuning unit and a second-order tuning unit; The first-order tuning unit includes a first inductor and a second inductor connected in parallel and grounded. The first inductor, the second inductor, and a first capacitor are connected in series, and the first inductor, the second inductor, and a second capacitor are connected in parallel. The first inductor is also connected in parallel to a first network adjustment port, which is used to connect a medium-wave antenna. The medium-wave antenna is used to make its antenna impedance at the first network adjustment port close to the resistance of the second capacitor through impedance transformation. The second-order tuning unit includes a third inductor coil, which is connected in parallel with a third capacitor. The third inductor coil and the third capacitor are also connected in series with a fourth capacitor, which is connected in series with a fourth inductor coil. The fourth inductor coil is connected to the transmitting end. The third inductor and the third capacitor are also connected to the first inductor through the second network adjustment port. The fourth inductor and the fourth capacitor are used to adjust the capacitive reactance to make the capacitive reactance value equal to the inductance value of the parallel resonant network of the third inductor and the third capacitor.

2. The improved medium wave multi-order matching network of claim 1, wherein: The second network adjustment port is used to superimpose the VSWR curve characteristics of the second-order tuning unit and the first-order tuning unit.

3. The improved medium wave multi-order matching network according to claim 1 or 2, characterized in that: The third inductor and the third capacitor are connected in parallel with a resonant interval of 12 medium wave frequencies.

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