JPH0634345U - Device for mitigating variations in wireless coupling to leaky cables - Google Patents

Abstract

(57) [Summary] (Correction) [Purpose] A standing wave is generated between the leakage cable installed in parallel and the antenna of the work vehicle along the running of the work vehicle. This fluctuation of the reception level is reduced. [Structure] The wireless control work vehicle operates with the functions of a transmitter 9 and a receiver 10 antenna 8. Leakage cable 2 and antenna 8
As the two-way coupling, the matching unit 3 adds to the transmitter 4 and the receiver 5, and a part of the output of the matching unit 3 is detected and widened to match the matching unit 3.
In addition, the transmission output becomes constant.

Description

[Detailed description of the device] [Industrial application field]   When using a leaky cable to remotely control a wireless work vehicle, This is a device for reducing the influence of waves and the like. [Conventional technology]   In the Radio Law up to now, the regulation on the weak electric field strength was loose. In the current state of enforcement of the new Radio Law, the transmission output is particularly weak, so The effect was significant, and video transmission became particularly difficult. [Problems to be solved by the device]   When installing a leaky cable as shown in Fig. 1 and remotely controlling a wireless vehicle, Due to the influence of standing waves, etc., the input level of the receiver may drop, making it difficult to control. It was. To solve this problem, take measures to reduce the level fluctuation of the receiver input. Devised. [Means to solve the problem]   When the transmitter of the work vehicle operates in the device shown in FIG. 1, its output signal is (8) The antenna is (2) coupled to the leaky cable and (5) added to the receiver. work When the position of the antenna (8) comes to point (a) in Fig. 2 as the car moves, the reception input level This lowering portion where the line is lowered is detected to generate a detection signal. Using this signal, ( When added to the matching device of 1, 3), the matching state becomes mismatched, and the point shown in FIG. If you move to point (b) or point (c), the level at point (a) will rise, so standing waves, etc. It is possible to reduce the level change due to. [Action]   In the device shown in Fig. 1, the leakage cable is in the matching state of the matching device, Due to the movement of the car, the transmitted carrier wave is coupled to the leaky cable and responds to standing waves etc. Then, the changed level is added to the (5) receiver, and the penetration part is detected and matched. In the case of an inconsistent state that returns to the reactor, the penetration point moves and the received input level changes. You can reduce the movement. 〔Example〕   In the device shown in Fig. 1, (2) the control signal from the outside causes mismatch at both ends of the leaky cable. A matching device is installed so that the combined signal from the transmitter is added to the receiver (5). work As the car moves, the output of the receiver has the characteristics including standing waves shown in Fig. 2. A detection signal is generated by this signal (6) amplifier, and the matching device of (1, 3) or (11) connection is made. Added to the coalition. When the work vehicle moves to point (a) in Fig. 2, (6) amplifier The control signal from causes the matching device to become inconsistent and moves to (b) and (b) in FIG. Fluctuations in the penetration point can be reduced. (11) The coupler is from (6) the amplifier The operation shown in Fig. 3 can be performed by coupling or anti-coupling with the control signal. [Effect of device]   A work vehicle can be operated by installing a leaky cable and remotely controlling it by wireless transmission of weak electric field strength. When it rolls over, it may interfere with calls and data transmission or image transmission due to the effects of standing waves. There was some damage, but by using this method, the obstacles are alleviated and the video transmission is also possible. It became possible.

[Brief description of drawings] Fig. 1 is a block diagram showing the outline of this device. FIG. 2 is a receiver input characteristic due to a standing wave or the like. FIG. 3 is a characteristic diagram for explaining an operating condition of this device. (1, 3) Matching device (2) Leakage cable (4) Control transmitter (5) Receiver (including video or data call) (6) Amplifier (differential shaping amplifier) (7) Controller (Work instruction and received data processing) (8) Work antenna (9) Transmitter (video and data or audio) (10) Receiver (〃 〃) (11) Combiner (for standing wave countermeasures) Fig. 2 (A) In order to represent the penetration portion of the reception level, the penetration of FIG.
C) It is an explanation for moving.

Claims (1)

[Scope of utility model registration request] 1. In wireless transmission using a leaky cable, as a measure against the change in the degree of coupling between the (8) antenna and (2) the leaky cable of the mobile station, the matcher of (1) and (3) is installed at the end of the leaky cable, Change the match, the second level of coupling
(A) Method of moving the penetration point to the third (b, c) point to make the degree of coupling of the antenna constant. 1 and 2 (11) Multiple (11) couplers are installed around the leaky cable by selecting the mounting position according to the situation such as standing waves. When the coupler is changed by the control signal, the second
Figure (b) Method to move the drop point to the point in Figure 3 (b, c) to keep the coupling level constant.