JP2010166232A - Signal processing apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a signal processing apparatus capable of improving characteristics of return loss and isolation, corresponding to UHF-band all channels. <P>SOLUTION: A connection 13 of an input port 11b of a transmission line 11 in a right corner wherein transmission lines 11 and 12 cross is bent at 90° with respect to a plane of the transmission line 12, and a connection of a terminal 12b of the transmission line 12 in a left corner is bent at 90° with respect to a plane of the transmission line 11, thereby an effect of the intersection between transmission lines 11 and 12 is eliminated. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a signal processing device used in a transmission station that transmits a broadcast signal such as terrestrial digital broadcast.

  Signal processing devices such as a digital transmitter synthesizer or a digital transmitter distributor are compatible with UHF (Ultra High Frequency) band all channels (470 MHz to 890 MHz) and are required to have higher power durability. . In addition, due to miniaturization and low cost, an isolator is often not used. Thus, a method using a 3 dB coupler that also serves as an isolator has been proposed.

  However, when configuring the 3 dB coupler, the end of the coupled line is bent to an appropriate angle on the same plane and connected to the input / output port by a 50 Ω transmission line. It is difficult to improve return loss and isolation. In addition, this effect makes it difficult to improve the line pattern over a wide band.

  As a related art related to this type, Patent Document 1 provides a notch for impedance matching at each port of a macrostrip line so that the directivity and isolation characteristics are good even when used in a high frequency band. A directional coupler that can be secured is shown. However, the thing of this patent document 1 has a problem that the basic characteristics as a circuit design and a directional coupler cannot be obtained when the directional coupler is configured for a high frequency, and the return loss and It is not related to isolation adjustment.

JP-A-7-226609.

  As described above, it is difficult to adjust the return loss and the isolation with the method using the 3 dB coupler.

  Accordingly, an object of the present invention is to provide a signal processing apparatus capable of improving the return loss characteristic and the isolation characteristic corresponding to the UHF band all channel.

  In order to achieve the above object, a signal processing apparatus according to the present invention includes a first transmission line having a digital broadcast signal input port connected to one end and a digital broadcast signal output port connected to the other end, A second transmission line coupled to the first transmission line to perform distribution processing or synthesis processing of the broadcast signal, and connected to an input port or output port of the digital broadcast signal at one end; An intersection between one end of the second transmission line and one end of the second transmission line is a first corner, and an intersection between the other end of the first transmission line and the other end of the second transmission line is a second corner. The port connection portion of the first transmission line of the first corner is bent in a direction perpendicular to the plane of the second transmission line, and the port connection portion of the second transmission line of the second corner is Orthogonal to the plane of one transmission line It is bended toward.

  According to this configuration, the port connection portion of the first transmission line of the first corner is bent in a direction orthogonal to the plane of the second transmission line, and the port of the second transmission line of the second corner The connection portion is bent in a direction orthogonal to the plane of the first transmission line, so that the influence of the intersection of the first transmission line and the second transmission line is eliminated. Correspondingly, the characteristics of return loss and isolation can be greatly improved.

  As described above in detail, according to the present invention, it is possible to provide a signal processing apparatus capable of improving the return loss characteristic and the isolation characteristic corresponding to the UHF band all channel.

The perspective view of the principal part of the divider | distributor in one Embodiment of this invention. The perspective view which showed the detail of the edge part of the transmission line shown in the said FIG. The perspective view of the principal part of the distributor for power proof used before. The characteristic view shown in order to demonstrate the previous bandwidth and return loss. The characteristic view shown in order to demonstrate the bandwidth and return loss in the same embodiment.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 1 is a perspective view of a main part of a distributor according to an embodiment of the present invention. FIG. 2 is a perspective view showing details of an end portion of the transmission line.

  In FIG. 1, transmission lines 11 and 12 are arranged in a vertically parallel manner in a box-shaped casing 100 to perform distribution processing of digital terrestrial broadcasting signals, and when the entire shape is focused, Is in a state of being. Note that the periphery of the housing 100 is shielded.

First, the transmission lines 11 and 12 will be described.
The transmission lines 11 and 12 are S-shaped by themselves. Further, the transmission lines 11 and 12 cross in opposite directions so as to be X-shaped when viewed from above. When operating as a distributor, an input port 11b to which a UHF band terrestrial digital broadcast signal is input is provided at one end of the transmission line 11, and an output port 11a from which the digital broadcast signal is output at the other end. Is provided.

  In addition, an output port 12a from which a digital broadcast signal is output is provided at one end of the transmission line 12. Note that the other end of the transmission line 12 is terminated. Here, the portion to be terminated is referred to as a termination portion 12b.

Next, the structure of one end of the transmission lines 11 and 12 will be described. Here, the connection part of the input port 11b and the connection part of the output port 12a will be described as a representative.
In the transmission lines 11 and 12, the connection portion 13 of the input port 11 b is bent at 90 degrees with respect to the plane of the transmission line 12. The connection portion 13 is L-shaped when viewed from above, and a horizontal piece is connected to the input port 11b. Further, the connecting portion 13 is formed with a vertical piece standing upright with respect to the base portion 13a. Further, a cut portion 13b is formed in the base portion 13a in order to improve return loss.

  On the other hand, the connection part (not shown in FIG. 1) of the termination part 12b of the transmission line 12 is also L-shaped like the connection part 13, and a horizontal piece is connected to the termination part 12b.

Next, the return loss obtained by the bending structure will be described.
In the past, as shown in FIG. 3, the power-resistant distributor uses strip lines for the transmission lines 31 and 32 provided in the housing 200. These transmission lines 31 and 32 are constructed of a coupled line and a 50Ω transmission line on the same plane. However, the impedance is disturbed by the intersecting portion of the coupling tip, and as shown in FIG. 4, it is difficult to suppress the return loss and the isolation to −20 dB or less.

  Therefore, in the present embodiment, the connection portion 13 of the input port 11b of the transmission line 11 at the right corner portion where the transmission lines 11 and 12 intersect is 90 degrees with respect to the plane of the transmission line 12 (the upper surface is shown in FIG. 1). And the connection portion of the terminal end portion 12b of the transmission line 12 at the left corner portion is bent at 90 degrees with respect to the plane of the transmission line 11 (showing the lower surface in FIG. 1), thereby eliminating the influence of the left and right corner portions. I did it.

  As a result, the return loss and the isolation are greatly improved to −20 dB or less as shown in FIG.

  As described above, in the above embodiment, the connection portion 13 of the input port 11b of the transmission line 11 at the right corner portion where the transmission lines 11 and 12 intersect is bent 90 degrees with respect to the plane of the transmission line 12, and the left corner portion By bending the connection portion of the terminal end portion 12 b of the transmission line 12 by 90 degrees with respect to the plane of the transmission line 11, the influence of the intersection of the transmission lines 11 and 12 is eliminated.

  Therefore, the return loss characteristic and the isolation characteristic can be greatly improved in correspondence with the UHF band all channel.

  In the above embodiment, the distributor has been described as an example, but a combiner may be used.

  Furthermore, the present invention is not limited to the above-described embodiment as it is, and can be embodied by modifying the constituent elements without departing from the scope of the invention in the implementation stage. In addition, various inventions can be formed by appropriately combining a plurality of components disclosed in the embodiment. For example, some components may be deleted from all the components shown in the embodiment. Furthermore, constituent elements over different embodiments may be appropriately combined.

  DESCRIPTION OF SYMBOLS 11, 12 ... Transmission line, 11a, 12a ... Output port, 11b ... Input port, 12b ... Termination part, 13 ... Connection part, 13a ... Base part, 13b ... Cut part, 100, 200 ... Case.

Claims (2)

A first transmission line connecting one end of the digital broadcast signal input port and the other end of the digital broadcast signal output port;
A second transmission line coupled to the first transmission line to perform the distribution process or the synthesis process of the digital broadcast signal, and connected to an input port or an output port of the digital broadcast signal at one end;
An intersection between one end side of the first transmission line and one end side of the second transmission line is defined as a first corner, and the other end side of the first transmission line and the other end side of the second transmission line. And the second corner of the first transmission line of the first corner is bent in a direction perpendicular to the plane of the second transmission line, and the second corner The signal processing device according to claim 1, wherein the port connection portion of the second transmission line of the corner is bent in a direction orthogonal to the plane of the first transmission line. The port connection portion of the first transmission line of the first corner has a bending angle of 90 ° with respect to the plane of the second transmission line,
2. The signal processing apparatus according to claim 1, wherein the port connection portion of the second transmission line of the second corner has a bending angle of 90 ° with respect to the plane of the first transmission line.

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