JPS59125085A - Recording system of multi-frequency fish detector - Google Patents

Abstract

PURPOSE:To obtain a recording system of a multi-frequency fish detector which causes no radio interference at all, by emitting an ultrasonic wave of plural frequencies into the water in the order prescribed in advance, recording only an echo signal reflected in said order, and generating an original key signal by changing the combination sequence of the frequency. CONSTITUTION:When a trigger pulse of a frequency prescribed in advance is outputted successively from an oscillation trigger generator 1, oscillators 21, 22 and 23 are operated successively, and ultrasonic waves of frequencies F1, F2 and F3 are outputted into the water from transmitters and receivers 31, 32 and 33. Their reflected echoes pass through the transmitters and receivers 31, 32 and 33 and are inputted to receivers 41, 42 and 43, respectively. These inputted reflected echo signals are brought to waveform-conversion by A/D converters 51, 52 and 53, respectively, and stored in memories 61, 62 and 63 by a write address signal of an address circuit 7. This stored signal is read out simultaneously from the address circuit 7 by a simultaneous read-out signal, and when it is synthesized by an AND gate 8, an oscillating signal (a) being in the same time relation, a reflected signal (c) from a shoal of fish, and a reflected signal (d) from the sea bottom pass through, and a radio interference signal (b) is erased.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a recording method for a multifrequency fish finder that transmits waves underwater in a predetermined order and records only the signals reflected in the predetermined order.

In recent years, most fishing boats are equipped with fish finders, but when fishing boats operate in close proximity to five fishing grounds, fish finders cannot perform to their full potential due to interference if they are on the same frequency. , a fish finder without interference was requested.

To solve these problems, equip a boat with two or more fish finders with different frequencies and use them separately, or use a two-frequency or multi-frequency fish finder by switching the frequency. A method is being taken.

However, these fish detection methods use a single frequency, so in order to completely prevent interference, more frequencies must be prepared, making the transducer larger and the cost significantly higher. In addition, this fish finder was unsuitable for small boats engaged in coastal fishing.

In order to eliminate the drawbacks of the conventional example, the present invention is characterized by emitting ultrasonic waves of multiple frequencies into water in a predetermined order and recording only the echo signals that are reflected in that order. By changing the order in which the frequencies are combined to create a unique key signal (frequency), the present invention provides a recording method for a multi-frequency fish finder that does not cause any interference. Embodiments of the present invention will be described in detail below with reference to the drawings.

FIG. 1 shows a block diagram of a recording system of a multi-frequency fish finder according to an embodiment of the present invention, in which 1 is a sequential oscillation trigger generator, 2. -22.23 is the oscillator, 3J, 32.3
3 is a transducer; 4. ．． 42°43 is memory, 5152.
53 is an A/D converter, 61.62.63 memory, 7 is an address circuit, 8 is an AND gate, 9 is a D/A converter, 1
0 is the recording section.

Next, the operation of this embodiment will be explained with reference to the waveform diagram of each part shown in FIG. First, when trigger pulses of a predetermined frequency are sequentially output from the sequential oscillation trigger generator l as shown in FIG. 2(a), the oscillator 2. ．． 22.
23 operate sequentially, and ultrasonic waves of frequencies F1, F2, and F3 are outputted into the water from the transducers 31, 32, and 33 as shown in FIG. 2 (b). These reflected echoes pass through transducers 31, 32, and 33 and are input to receivers 41, 42, and 43, respectively, as shown in FIG. 2(c).

This receiver4. ．． The reflected echo signal input to 42 and 43 is sent to A/D converter 5. ．． 52.5B respectively in Figure 2 (
The waveform is converted as shown in d) and stored in each of the memories 6□ and 62.63 using the write address signal of the address circuit 7. Here, in the waveforms shown in FIGS. 2(c) and (d), a is the oscillation signal, b is the interference signal, and C
is the reflected signal from the school of fish, and d is the reflected signal from the seabed.

Each signal has the same time relationship. This memory 6,
．． The signals respectively stored in 62 and 63 are simultaneously read out from the address circuit 7 by the simultaneous read address signal as shown in FIG. ), the oscillation signal a, the reflected signal C from the school of fish, and the reflected signal d from the seabed, which are in the same time relationship, pass through and the interference signal S is eliminated.

In the recording method of the multi-frequency fish finder of this embodiment configured as described above, the reflected waves of the ultrasonic waves of multiple frequencies transmitted sequentially are received only when they return in the same order, so interference is avoided. The advantage is that there is no In addition, by changing the combinations of multiple frequencies in various ways, it is possible to give each fish finder on each fishing boat its own key signal (frequency), thereby ensuring that no interference occurs at all. I can do it.

As explained above, according to the present invention, by using a plurality of frequencies simultaneously and transmitting and receiving in a predetermined order, key signals can be created in the order in which the frequencies are combined. It is possible to provide a fish finder that does not cause interference.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of a recording system of a multi-frequency fish finder according to an embodiment of the present invention, and FIG. 2 is a waveform diagram of each part of FIG. 1. 1... Sequential oscillation trigger generator, 21.22.23.
...Oscillator, 31.32.33...Transducer, 4. −
42.43...Receiver, '5t, 52.53...A
/D converter, 61.62.63...memory, 7...
Address circuit, 8...AND gate, 9...D/A
Converter, 10...recording section. Patent applicant: Keisuke Honta No. 20 (d) (f)

Claims (1)

[Claims] A sequential oscillation trigger generator that sequentially sends out a plurality of trigger signals, and a plurality of oscillators that operate at different frequencies in a prespecified order based on the trigger signals output from the sequential oscillation trigger generator. a plurality of transducers each connected to the oscillator and radiating ultrasonic waves into the water; and a plurality of receivers each amplifying the echo signals received by the transducer. a plurality of A/D converters that convert the output of the receiver into waveforms;
A memory for storing the outputs of the A/D converters, and a memory for writing the outputs of the A/D converters in the order of predetermined frequencies using a write address signal, and simultaneously reading them from the memory using a read address signal. an AND gate circuit that synthesizes the output read out from the memory by the read address signal of the address circuit, and a recording section that displays the output of the AND gate circuit. A recording method for a multi-frequency fish finder characterized by recording only reflected signals received in sequence.