JPS6141214A - Bidirectional distributor - Google Patents

Abstract

PURPOSE:To attain transmission of signals in both directions between optional two terminals by connecting three distributors in a circular form. CONSTITUTION:Distribution units BUs 7-9, HPFs 10-12 and LPFs 13-15 are connected circularly. The input signal sent from a distribution terminal BR16, for example, is divided into the high and low frequency components by the HPF10 and LPFs 13-15. The low frequency component is distributed directly to other BRs 17 and 18 through LPFs 13-15; while the high frequency component is divided into two parts by the BU7 through the HPF10 and supplied to the distribution terminals of BUs 8 and 9 and then delivered to BRs 17 and 18 through HPFs 11 and 12. Such a complete bidirectional distributor is symmetrical when viewed from any distribution terminal. Therefore the input signals given from the BRs 17 and 18 are also distributed in the same way.

Description

DETAILED DESCRIPTION OF THE INVENTION FIELD OF INDUSTRIAL APPLICATION The present invention relates to a circuit configuration of a device that bidirectionally distributes broadband signals.

Conventional Structure and Its Problems FIG. 1 shows the circuit structure of a distributor for television common listening equipment using a conventional distribution transformer. A high frequency signal inputted from the input terminal 1 is distributed by the distribution transformer 4, and the power is equally distributed to the distribution terminals 2 and 3 and output. However, conversely, the signal input from the distribution terminal 2 is output to the input terminal 2 by the distribution transformer, but not to the distribution terminal 3. Similarly, the signal input from the distribution terminal 3 is also not output to the branch terminal 2. In this way, 3
Since the two terminals are not equal, there are restrictions when configuring the network. Furthermore, the distribution transformer is several hundred KH.
Since this is a high frequency distribution transformer that can only pass signals of z or more, it is not possible to efficiently distribute low frequency signals such as baseband signals. Note that 6 and 6 are resistors and capacitors for impedance matching.

Purpose of the Invention The present invention solves the above-mentioned conventional problems and
The object of the present invention is to provide a method for bidirectionally distributing wideband signals up to high frequency signals between two arbitrary terminals among three terminals.

Structure of the Invention The present invention connects two distribution output terminals of one distribution transformer to distribution terminals of two separate distribution transformers, and further connects unconnected distribution terminals of the two connected distribution transformers. This is a high-frequency bidirectional distributor in which three distribution transformers are arranged in a ring shape by connecting them together.

Description of the Embodiment Since the distribution transformer has the same input and output impedance at all terminals, each terminal of the three distribution transformers can be connected. A high frequency signal input from the input terminal of one distribution transformer is divided into two by the distribution transformer. Since the two divided signals are respectively input to the distribution terminals of adjacent dividers, half the signal power of the input signal is output to the input terminal of each distribution transformer. Therefore, one quarter of the high frequency signal input to this bidirectional divider is distributed to the other two terminals. the other 2
High frequency signals input from the three terminals are also distributed in the same way, so complete bidirectional distribution of the high frequency signals can be achieved between the three terminals.

Next, a duplexer is provided at the input terminal of the high frequency band divider,
Only high frequency signals are input to the high frequency band divider,
A bypass circuit is provided between each terminal to allow low frequency signals to pass through.

At this time, by appropriately selecting the characteristics of the duplexer, it is possible to obtain a fully bidirectional divider that can transmit signals in both directions in all frequency bands.

An embodiment of the present invention will be described with reference to FIG. FIG. 2 is a block diagram of a fully bidirectional distributor according to an embodiment of the present invention. Public listening distribution Unisol l-B U
7 to 9, high frequency pass filters HPF1o to HPF12, and low frequency pass filters LPF13 to LPF16 are connected in a ring as shown in the figure. This is called a complete bidirectional distributor. Next, the operation will be explained. For example, distribution terminal BR1
The signals input from 6 to 18 are separated into high frequency signal components and low frequency signal components by HPFlo and low frequency pass filters LPF1s to 16. The low frequency signal component is LP1
It is directly distributed to other BRs 17 and 18 through BRs 13 to 15. However, impedance is not matched for low frequency signals here.

Next, the high frequency signal component is inputted to the input terminal of BU7 by HPFlo, divided into two, inputted to the distribution terminals of BUs and 9, respectively, and passed through HPFll and HPF12.
It is output to BR17 and BRls.

This fully bidirectional distributor is BU7, BUls.

Since the distribution terminals of the BU19 have a symmetrical structure when viewed from any terminal, the signals inputted from the distribution terminals BR17 and BR18 are also distributed in the same manner as in the above case. In this case, the power loss between input and output is the LPF for low frequency signal components.
However, since the high frequency signal component passes through the BU twice, theoretically a loss of edB occurs.

FIG. 3 shows a specific circuit diagram. High frequency pass filter H
Capacitors are used as the PFs 1o to 12, and choke coils are used as the low frequency pass filters and LPFs 13 to 16. Furthermore, distribution lances are used as the public listening distribution units 7 to 9. Note that 19 to 21 are impedance matching resistors of each distribution transformer. In this way, signals over a wide band from direct current to the UHF band can be bidirectionally distributed with the simplest configuration.

Effects of the Invention By connecting three dividers in a ring, signals can be transmitted bidirectionally between any two terminals, and furthermore, a duplexer is provided at each of the three input terminals to transmit low frequency signals. By providing a bypass circuit, it is possible to transmit a wideband signal from a low frequency range to a high frequency range.

[Brief explanation of the drawing]

FIG. 1 is a circuit diagram of a conventional TV public listening distributor, FIG. 2 is a block diagram of a bidirectional distributor according to an embodiment of the present invention, and FIG.
The figure is a specific circuit diagram of the same distributor. 7-9... Common listening distributor, 10-12...
- High frequency pass filter, 13-15...Low frequency pass filter, 16-18...Distribution terminal. Name of agent: Patent attorney Toshio Nakao and 1 other person No. 1
Figure 2 Figure 3

Claims (2)

[Claims] (1) The two distribution terminals on the output side are connected to the distribution terminals of the adjacent distribution transformers, and the three distribution transformers are connected in a ring. A bidirectional distributor characterized by extracting a signal from the input side of another distribution transformer. (2) One input terminal of each distribution transformer is connected to a distribution terminal via a high frequency pass filter, and the distribution terminals are connected to each other in a ring via a low frequency pass filter, and the other input terminal of each distribution transformer is connected to the distribution terminal through a high frequency pass filter. 2. The bidirectional distributor according to claim 1, wherein each of the terminals is grounded.