JPS5934201Y2 - Synchronous pulse detection device - Google Patents

Description

[Detailed description of the invention] This invention wirelessly transmits detection results regarding water depth and fish schools obtained at any point to a remote point, and displays the information at the remote point in its original form on a recorder. In mid-water towing fisheries, a telesounder transmits information about the net being towed behind, such as the opening of the net, the distance between the net and the seabed, and the depth of the school of fish, to the distant vessel towing the net. This invention relates to a synchronous pulse detection device necessary for synchronous operation of a recorder such as a net graph displayed on the recorder.

To transmit data from a remote location, receive it, and reproduce it, it is necessary to synchronize between the transmitter and the receiver. Usually, a pilot pulse of a fixed period and a synchronization pulse delayed by a fixed period of time from this pilot pulse are used. The sending and receiving side first receives a pilot pulse, then opens the gate circuit after a predetermined delay and detects the synchronizing pulse.

In this case, the recording range of the recorder on the receiving side is 0 to 5.
It is convenient if it is always constant like 0m, but in actual use, the recording range often changes depending on the environment, and when the recording range is changed, the running speed of the recording pen changes accordingly. The time relationship between the pilot pulse and the synchronization pulse must be adjusted every time a change is made, which requires manual adjustment and is quite troublesome.

The present invention eliminates the above-mentioned drawbacks, eliminates the need for adjustment regardless of the recording range, and prevents malfunctions due to noise, etc., and will be described in detail below with reference to examples.

FIG. 1 is a block diagram of the embodiment, and FIG. 2 is an explanatory diagram of the operation, and the illustrations correspond to the symbols written in various places in FIG. 1.

As shown in Fig. 2A, the transmitting side sends a pilot signal P with a period TP and a synchronization signal -'rs P2 delayed by a time Ts from the pilot signal, where the ratio R of Ts and Tp is constant. is the value of

When these signals are processed by the detection waveform shaping circuit 1, the second
It becomes an illustration.

On the other hand, after passing through the E wave generator 2 and the waveform shaping circuit 3, the synchronizing signal P2 is removed from the output, and only the pilot signal is obtained as shown in FIG.

This output drives the sawtooth wave generation circuit 5 to generate a sawtooth wave, and the pulse generated by operating the monostable multi 4 with the first pilot signal (see Fig. 2 2) generates the sawtooth wave. Then, the sawtooth wave generating circuit 5 is reset and at the same time, the next sawtooth wave is immediately started again (see FIG. 2E).

That is, the sawtooth wave is obtained by converting the time from one pilot pulse until the next pilot pulse arrives in correspondence with the voltage.

Since the outputs of the monostable multi 4 and the sawtooth wave generation circuit 5 are applied to the sampling hold circuit 6, the maximum value Vp of the sawtooth wave voltage is held (see FIG. 2).

Next, in the voltage divider circuit 7, the held voltage is stepped down, that is, multiplied by the proportionality constant indicated by ='l'3 above to create the p voltage (see Figure 2, G), and applied to the comparator circuit 8.
When compared with the output of the sawtooth wave generating circuit 5, the output shown in FIG. 2C is obtained.

Since the outputs of the detection waveform shaping circuit 1 and the comparison circuit 8 are applied to the gate circuit 9, its output becomes as shown in the second diagram.
A synchronization pulse corresponding to the synchronization signal P2 is obtained, and as is clear from the operation progress of the previous stage, even if there is noise or other interference between the pilot pulse and the synchronization pulse, it will not be affected by this and will ensure normal operation. Synchronization pulses can be extracted.

As mentioned above, the practical effects of the present invention are extremely large.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of an embodiment. 1...Detection waveform shaping circuit, 2...R wave generator, 3...
Waveform shaping circuit, 4... Monostable multi, 5... Sawtooth wave generation circuit, 6... Sampling hold circuit, T.
... Voltage dividing circuit, 8... Comparison circuit, 9... Gate circuit. FIG. 2 is an explanatory diagram of the operation.

Claims (1)

[Scope of utility model registration request] A device configured to receive a pilot pulse of a constant period Tp transmitted from a remote point and a synchronization pulse delayed by a constant Ts from the pilot pulse, and to discriminate and detect the synchronization pulse from among them. One receiving path includes an F-wave device that takes out only the previous Hbq loft pulse, and a waveform shaping circuit that shapes the output wave of the F-wave device.
a monostable multi to which the output of the waveform circuit is applied; a sawtooth wave generation circuit to which the output of the monostable multi and the output of the waveform shaping circuit are applied; the output of the sawtooth wave generation circuit and the monostable; a sampling hold circuit to which multiple outputs are applied; and a voltage dividing circuit that steps down the maximum value of the sawtooth voltage generated by the sawtooth wave generation circuit held in the sampling hold circuit at a ratio of R=Ts/TPO. and a comparison circuit to which the output of the voltage dividing circuit and the output of the sawtooth wave generation circuit are applied, and the other receiving path passes both the pilot pulse and the synchronization pulse to determine the waveform. It has a detection waveform shaping circuit for shaping, and a gate circuit to which the output of the detection waveform shaping circuit and the output of the comparison circuit are applied, so that a synchronization pulse is detected at the output of the gate circuit. A synchronous pulse detection device comprising: