JPS6047589A - Wide-band channel system - Google Patents

Abstract

PURPOSE:To make a multiple connection of outgoing lines of switches and extend channels without increasing crosstalk of channels by providing plural lattice type switches constituted by adding switches for crosstalk reduction to all outgoing-side terminals of matrixes which constitute a primary switch. CONSTITUTION:The lattice type switches P11-Pl1 are constituted by adding switches X11-X1n which are turned on and off to output terminals B1-Bn of output sides (n) of (m)-input (n)-output switch matrixes Q11-Ql1. A multiple connection of a necessary number of output terminals at the same positions of the lattice type switches P11-Pl1 is made to constitute a channel device. A wide-band channel system is composed of this channel device; the number of wiring is reduced without deteriorating crosstalk characteristics of channels and the extendability of channels is improved.

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field of the Invention The present invention relates to a broadband channel system, and more particularly to a broadband channel system capable of reducing crosstalk.

Conventional technology and problems Conventionally, when constructing a single-stage concentrator communication line with a large number of input/output terminals, a large number of small-scale switch matrices (hereinafter abbreviated as primary switches) are used. A configuration in which multiple outgoing lines are connected is common. but,
In this conventional configuration method, crosstalk is surrounded by multiple outgoing lines and multiple crosstalk becomes large, so in order to apply it to a wideband communication path, such as a video signal communication path, it is necessary to tighten the crosstalk characteristics for the primary switch. There were problems with its feasibility and economy. In order to improve this, a wideband channel configuration shown in Fig. 1 has been proposed (for example, IEICE Technical Report C875-
1 [10, 1975).

In FIG. 1, LC is a line concentrator, A11. ~A
1m.

~, At1~Alxn are its input terminals, B1~ByL
are the same output terminals, Q11~. Qtl is a switch matrix with m inputs and n outputs (hereinafter abbreviated as mXn) and constitutes a primary switch, sl sn is a switch array of tXl (hereinafter abbreviated as secondary switch), and M is an input of the concentrator channel device LC. The number of terminals, N, is also the number of output terminals, and in the example of FIG. 1, N=n. In addition, the primary switch Q
11 to Qt1 are switch matrices in which m conductors connected to m input terminals and n conductors connected to n output terminals are arranged to intersect with each other, and switches are provided at the intersection points. configured. Each of the secondary switches 81 to Sn is arranged so that n conductors connected to n input terminals intersect with one conductor connected to one output terminal, and the switch ( 811 to 81Ja, etc.).

Each of the above-mentioned switches may be a switch that performs on/off operation, and may be a mechanical switch or an electronic switch. However, even when these switches are in an off state, there is a small capacitance between the switches, and it is difficult to completely eliminate signal leakage. 111 in FIG. ~11n,
~1m1. ~1mn etc. illustrate the intersection point switch of the primary switch Q11, and 811~S1t illustrate the intersection point switch of the secondary switch S1.

Here, m is the number of input terminals of each primary switch Q11 to Qt1, n is the number of output terminals, and t is the number of primary switches Q11.
˜Qt1. The number M of input terminals of the line concentrator LC is mXt, and the number of input terminals of the secondary switches S1 to sn is input from the first (1≦f≦n) output terminal of the primary switches Q11 to QA1, respectively. is equal to n.

The reason why crosstalk can be reduced with the configuration shown in FIG. 1 is that the output sides of the primary switches (Q11 to Qt1) are connected to the secondary switches (81 to Sn) without being multi-connected. That is, the required input terminals (A11 to A11) of the line concentrator LC
Ahn) and output terminals (B1 to Bn),
The cross-point switch of the primary switch and secondary switch that connects the above two terminals is closed, but all other cross-points in the secondary switch are kept open, so the signals that become crosstalk are in the open state. Since the signal passes through the primary switch and the secondary switch in two stages, multiple crosstalk is reduced.

However, when realizing the configuration shown in Figure 1, the primary switch Q
11~Qz1? One possible method is to make each of the secondary switches S1 to Sn into an LSI and mount them on a printed circuit board, or to mount the primary switches Q11 to Qt1 and the secondary switches 81 to Sn on a printed circuit board and connect them using a back wiring boat or the like. It will be done. When the number M of insulators and the number N of output terminals increase, crosstalk between the parallel wiring cannot be ignored, so it is necessary to reduce the crosstalk by widening the wiring space or the like. Therefore, it is necessary to lower the packaging density or use a multilayer pattern in the wiring portion, which poses problems in packaging.

Furthermore, even at a stage when there are few subscribers, such as in the initial stage of introduction, the secondary switch must be installed in a fixed manner to some extent, which poses a problem in terms of expandability.

Purpose of the Invention In order to solve these drawbacks, the present invention provides a plurality of lattice-type switches in which crosstalk reduction switches are added to all terminals on the output side of the switch matrix constituting the primary switch. The purpose of this is to significantly reduce the number of wires without deteriorating the crosstalk characteristics of the communication path, and to create a communication path with good expandability. It is about realization.

Examples of the invention Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 2 is a connection diagram of the first embodiment of the present invention.

This embodiment is configured as a concentrator channel.

In Fig. 2, -LC is a line concentrator, A11°~
A1m~t At1~Atm are its input terminals, B1.
~Bn is the same output terminal, Q11~Qt1 constitutes a primary switch with an mXn switch matrix, and P11~
Pt1 is a lattice type switch, and a switch (X11 to X1n in Fig. 2) that can be turned on and off is added to each output terminal side of the primary switch matrix QH to Qt1, respectively, to control the output of the lattice type switches P11 to Pt1. It consists of terminals. P11 to pt1 will be referred to as lattice type switches to distinguish them from other switch matrices, such as Q11 to Qt1. M is the number of input terminals of the line concentrator LC, and N is the number of output terminals. In the example of FIG. 2, N=n as in FIG. 1. In addition, the primary switch Q
11 to Qt1 are arranged such that m conductors connected to m input terminals and n conductors connected to n output terminals are crossed,
This is a switch matrix with switches provided at the intersection points. The lattice type switches P11 to Pt1 each include primary switches Q11 to Qt1, and as illustrated in Pll, their n output terminals are connected to the switch (X1
1 to X1n) to the output terminal B of the line concentrator LC.
1 to Bn side. The above switch is on/off.
Any device that turns off may be used, and may be mechanical or electronic. However, even when these switches are in an off state, a minute capacitance exists between the switches, making it difficult to completely eliminate signal leakage. In Figure 2, 111. ~11n, ~1m1. ~1mn etc. illustrate the intersection point switch of the primary switch Q11.

Here, m is the number of input terminals of the primary switches Q11 to Qt1 or lattice switches P11 to Pt1, n is the number of output terminals, and t is the number of primary switches QH to Qt1 or lattice switches P11 to Pt1. be. The number M of input terminals of the line concentrator LC is m x t. In addition, the number N of output terminals of the line concentrator LC is as follows:
Since n is constructed by connecting the first (1≦f≦n) output terminals of the primary switches Q11 to Qt1 or the lattice switches P11 to Pt1 in multiple ways, it is equal to n as in FIG. 1.

The switch connecting the output of the primary switch Q11 of the secondary switch S1 of the line concentrator LC shown in FIG. 1 is the lattice switch P11 of the line concentrator LC shown in FIG.
It can be considered to have the same function as the switch It is 1/1 of the conventional one shown in Figure 1, and is extremely effective in improving the mounting efficiency of the wiring section. In addition, this embodiment has a large economical effect by reducing the number of printed layers in the wiring section.Furthermore, since the wiring section and the grid switch section can be connected by simple multiple connections, it is easy to add switches, and the concentration ratio can be increased. Changes can be easily made by simply increasing t (the number of primary switches or lattice switches).

In this embodiment, by appropriately selecting the number m of input terminals, the number n, and the number t of output terminals of the primary switches Q11 to Qt1, it is possible to configure not only a concentrating type but also a non-concentrating type communication path device. .

In the embodiment shown in FIG. 2 above, the number N of output terminals is equal to the number n of output terminals of the primary switch (N=n), but
FIG. 3 shows the second embodiment of the present invention, which can be
It is a connection diagram of the Example. In FIG. 3, Lσ is a channel device, L1 to Lr are r partial channel devices having the same configuration as the concentrator channel device LC shown in FIG. 2, and A1
1 to A1m and -At1 to ALm are input terminals of the communication path device LC', and B11 to B1YL to Br1 to Brn are output terminals. Inputs from input terminals A11-AAm are branched and input to corresponding input terminals of partial channel devices L1-L, respectively, via buffer amplifiers BA. Each output terminal B11 of the partial channel devices L1 to L.
~B1n*~*Br1~Brn constitute output terminals of the present communication channel device LC'.

Therefore, the number N of output terminals of the communication channel device LC' becomes nXr, and n(grid switch P11.~Pt1.~+Plr
- The number of output terminals such as Ptr etc.) can be increased.

In the channel device LC' of FIG. 6, the buffer amplifier B
A connects each lattice type switch P11 to Pt11 to .
In addition to suppressing the drop in impedance when branching to the Plr-Ptr input terminal, the fact that the signal has directionality within the buffer amplifier BA is used to block crosstalk signals from other lattice switches, thereby reducing crosstalk. Can be limited to own grid type switch. Note that the buffer amplifier BA may be a single-manpower multi-output branch amplifier. As a result, crosstalk is reduced by the number M of input terminals and output terminals of the channel device LC',
N is irrelevant, and the crosstalk standard required per cross-point switch remains unchanged. Lattice type switch P1 in Fig. 3
1 to Pt1 j to P1r to PZr can also be implemented in a package as shown in FIG. 6 by LSI, and in this case, the output multi-wires are wired within the package. Furthermore, when the lattice switch P11 or the like is mounted on a package, the output multi-line can be realized with a back wiring board or the like.

If the number of outputs is equal to the number of output wires of the effect of the invention, it can be realized by simple multi-connection of output terminals as in the first embodiment, and if the number of output terminals is greater than the number of output wires of the lattice switch, it can be realized by the second embodiment. By providing a buffer amplifier on the input side as in the example and connecting multiple output lines of the lattice switch via the buffer amplifier, expansion is easy, there is little crosstalk, and wideband communication paths with any switch size can be made economically. There are effects that can be achieved.

Further, the present invention has the advantage that a wideband communication path with little crosstalk can be easily realized even when a multi-stage link is configured using a known technique using the communication path device realized.

In addition, since the present invention aims to improve the crosstalk characteristics by devising the configuration and takes advantage of various advantages,
There are no restrictions on the structure of the switch or the type of switch.

[Brief explanation of the drawing]

Figure 1 is a diagram showing the configuration of a conventional wideband channel device;
The figure is a block diagram of a first embodiment of the present invention, and FIG. 3 is a block diagram of a second embodiment of the present invention. M... Number of input terminals, N... Number of output terminals, P11 to P
t1~P1r """Lr... Lattice type switch, m.
...Number of grid-type switch input terminals, n...Number of grid-type switch output terminals, A1. ~A1m-name Q1~Az□...
Input terminals, B1-Bn* B11-B1U. ~, B, 1~nrn...output terminal, L, r...number of switches, 111~11n, ~, 1m1~1mn; X1
1~X1n...switch, BA...buffer amplifier, Qll j Qtl...mXn switch matrix (primary switch), S1~Sn...tXl switch row (secondary switch) Fig. 1 1Bn N (=n) Figure 2 B1---(n) ---B n N (=n)

Claims (2)

[Claims] (1) A plurality of lattice-type switches configured by adding on/off switches to each output terminal side of a switch matrix with m inputs and n outputs (m and n are integers of 2 or more) are provided, and each of the above A wideband communication path system characterized by multiple connections of the required number of output terminals of grid-type switches at the same position. (2) A plurality of lattice-type switches configured by adding on/off switches to each output terminal side of a switch matrix with m inputs and n outputs (m and n are integers of 2 or more) are provided, and each of the above A wideband communication path system characterized by using a plurality of communication path devices configured by multi-connecting the required number of output terminals of grid-type switches at the same position.