JPS6256703B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a guided radio transmission system for data transmission between a mobile station and a ground station.

When transmitting data using guided radio, a crossed pair of wires is used, which is made by arranging two conductors at a predetermined period so that they intersect, in order to reduce external noise and prevent interference waves from being emitted to the outside. This is becoming common.

By the way, since instantaneous signal interruption occurs at the intersection of crossed pairs of wires, the conventional system configuration is as shown in FIG. 1.

In FIG. 1, 1 and 2 are intersecting pairs having intersections every period P, 3 is a mobile station including a transmitter 4 and a loop antenna 5, 6 is a π/2 phase shifter 7,
A ground station including an adder (subtractor) 8 and a receiver 9. The crossed pairs 1 and 2 are superimposed with a shift of P/2, and the signal from the mobile station 3 enters the crossed pairs 1 and 2 from the loop antenna 5, and the signal from the crossed pair 1 is at about 90 degrees. After creating a phase difference, the signal is combined with the signal from the other crossed pair and received at the ground station 6. Conversely, the signal from ground station 6 is 90
Power is fed to the crossed pairs 1 and 2 with a phase difference of .degree., and is received by the mobile station 3 via the loop antenna 5.

This method can prevent instantaneous interruption of the signal at the crossing point, but since the crossing periods of the crossing pairs 1 and 2 are equal, the crossing point of one crossing pair is the same as the crossing of the other crossing pair. If the cable is not positioned perfectly in the center of the area, crosstalk between lines will increase as the line length increases, making it difficult to maintain a constant phase difference between lines, and depending on the location, the reception level may drop. There is a high possibility that a drop in data will occur, causing a code error in the data signal.

The present invention has been made based on the above, and includes:
The object of the present invention is to provide a guided radio transmission system that can prevent a drop in reception level without requiring strict alignment of crossed pairs.

That is, in the present invention, the intersections of two pairs of intersecting pairs are shifted from each other, and the period of the intersection of one intersecting pair is changed from the intersection of the other intersecting pair at corresponding parts of the intersecting pairs. It is characterized in that it is 2n times the period (n is a positive integer).

FIG. 2 shows an embodiment of the present invention, in which 21 is a crossed pair line having an intersection part every period 2P, 22 is a crossing pair line having an intersection part every period P; The intersection of the line 21 and the intersection of the intersecting pair line 22 is 1/1 of the basic intersection period P in the longitudinal direction.
The cables are laid offset by 2.

Note that the mobile station 3 and the ground station 6 are the same as in FIG. 1, and the communication form is also the same as in FIG.

In this configuration, the period of the intersection of the crossed pairs 21 is twice that of the crossed pairs 22, so even if there is a shift in the position of the intersection between the crossed pairs 21 and 22, crosstalk will not occur. will almost disappear.

FIG. 3 is an explanatory diagram of another embodiment of the present invention, in which 31 and 32 are intersecting paired lines having portions of intersection period P and portions of intersection period 2P alternately at predetermined lengths. , the intersection period P of the intersecting pair 31
Intersection period 2P of pair line 32 intersecting at part (2P)
The part (P) is located. Further, the intersections of the intersecting pairs 31 and the intersecting pairs 32 are shifted in the longitudinal direction by 1/2 of the basic intersection period P.

With such a configuration, crosstalk is almost eliminated as in the embodiment of FIG.

In addition, in this embodiment, two pairs of intersecting pairs 3
1 and 32 can have the same structure, and even if the length of the line becomes long, the line formed by the crossed pair 31 and the line formed by the crossed pair 32 can be The phase constant between the two can be kept almost constant, and good communication conditions can be obtained over long distances.

That is, in the case of the embodiment shown in FIG.
Since the intersection periods of lines 1 and 22 are different, as the line length increases, the phase difference increases as shown in FIG. 4, making it difficult to transmit and receive with a 90° phase difference. On the other hand, in the case of this embodiment, since the crossed pairs 31 and 32 have the same structure, there is almost no change in the phase difference even if the line length increases, as shown in FIG.

As explained above, according to the present invention, a good communication state can be obtained without requiring accurate alignment between each crossed pair. It is now possible to construct a railway line simply by stacking the pieces manufactured in the same shape, which greatly simplifies the installation.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram of a conventional example, FIG. 2 is an explanatory diagram of one embodiment of the present invention, FIG. 3 is an explanatory diagram of another embodiment of the present invention, and FIGS. 4 and 5 are diagrams of phase change. It is an explanatory diagram. 21, 22, 31, 32: crossed pairs, 3: mobile station, 6: ground station.

Claims (1)

[Claims] 1. Two pairs of intersecting wires having periodic intersections are installed along the traveling route of a mobile object, with the intersections being shifted from each other in the longitudinal direction, and when transmitting from a mobile station to a ground station, In this method, the received signals of each crossed pair are given a phase difference of 90 degrees from each other before being combined. When transmitting from the ground station to the mobile station, a phase difference of 90 degrees is given to each other before being combined. In an inductive wireless transmission system in which power is supplied, the intersection period of one intersecting pair is set to 2n times the intersection period of the other intersecting pair (n is a positive integer) at corresponding parts of both intersecting pairs. ), and these intersecting pairs are laid with the intersecting portions shifted in the longitudinal direction by approximately 1/2 of the basic intersecting period P. 2 One intersecting pair has a uniform intersection period P in the longitudinal direction, the other intersecting pair has a uniform intersection period 2nP (n is a positive integer) in the longitudinal direction, and the intersection 2. The guided wireless transmission system according to claim 1, wherein the guided wireless transmission system is installed so that the wires are shifted by approximately P/2 in the longitudinal direction. 3 Both intersecting pairs have components of the intersection period P and parts of the intersection period 2nP (n is a positive integer) alternately at predetermined length intervals, and the intersections are shifted approximately P/2 in the longitudinal direction. The guided wireless transmission system according to claim 1, which is installed.