JPS58127186A - Finder - Google Patents

Abstract

PURPOSE:To prevent the generation of noises while simplifying and miniaturizing the construction of a finder with a reduction in the number of switches for selection of vibrators by arranging matched filters for pulse compressing a recevied wave output of an incoming signal as specified. CONSTITUTION:Matched filters used to pulse compress an incoming recevied wave output by a pulse response are compsed of an A/D converter 50, memory circuits 51 and 53, a controller 55 for controlling writing and reading required thereby, a multiplier 52, an accumulator 54 ad the like. Recived wave outputs from wave receivers within the range of 90 deg., are subjected to A/D conversion sequentially applied to the multiplier 52 via the memory device 51 and multiplied by a weight responded from the memory device 53 to be accumulated into the accumulator 54. Then, according to the results of a required integration, a received wave beam whose center angle is within 90 deg. is outputted to indicate a bearing. This eliminates interpolators or the like making the selection of vibrators simple and easy to perform. Reduced number of switches for selection of vibrators can simplify the miniaturize the construction of a finder while preventing the generation of switching noises.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a detection device d that receives signals arriving from a wide range of directions and displays, for example, the distance or direction of the source of the incoming signal.
Regarding. In particular, this invention provides
A device that can sequentially form all received beams in a central angle direction by oxidizing the output signals of a plurality of receiving elements, and increase the number of received beams in a constant angle direction. Regarding.

The present invention can be implemented in underwater detection devices such as fish finders, radar devices, and direction finders.

Hereinafter, the case where the present invention is implemented in an underwater detection device will be explained.

A conventional device is described in US Pat. No. 3,846,745. This underwater detection device consists of a plurality of S-faces arranged at equal intervals on a circle, an interpolator that sends interpolated received signals, and each of them connects to a transducer via the interpolator. It consists of a beamformer consisting of a plurality of 4-element elements, a switch that connects each transducer to an interpolator, and a display that displays the output signal of the beamformer. The movable element groups are sequentially selected by the switch, and the incoming signal 1 captured by the selected transducer is transmitted to the beamformer, so that received beams are sequentially formed in the direction of the central angle.

However, in this conventional system, many switches are used to select the predetermined transducer width from time to time, and therefore, the same connection between the switch and the transducer becomes a problem, and when creating a switch. It had some drawbacks such as generating noise.

The purpose of this invention is to provide a novel conceptual detection device. The aim is to provide a miniaturized underwater detection device by significantly reducing the number of switches. Another purpose is to use an underwater device that does not generate switching noise. □ Receives signals coming from the direction of Guangdong and displays information related to the arrival of No. 100 on the display means. The detection device according to the present invention includes a receiving means for receiving all incoming signals so that their frequencies change based on the Doppler effect, a matched filter for outputting the gold pulse Eai of the output signal of the receiving means, and a matched filter for receiving the gold pulse Eai of the output signal of the receiving means. display means for displaying the output signal;
It is comprised of a control means for controlling the wave receiving means and the display means so that they are related to each other.

Hereinafter, the principle of how this invention forms a receiving beam when the color is tilted underwater will be explained.

A frequency modulated signal in which the frequency 7 changes directly by kT within period T is expressed by the following equation.

f(t) 工 eJ (Woj ]kt) , , ,
, , , , , , 18. (1) 2πB where k = −−−−−−− B: Frequency change range In an underwater detection device, the signal expressed by the above equation (1) is approximately This is obtained by the above-mentioned wave receiving means which receives waves in a changing manner. The signal expressed by the above equation (1) is supplied to a matched filter having an impulse response expressed by the following equation.
, , , , , , , , , , , (2) The output of the matched filter is expressed by the following equation.

g(t) ”= f(t) ■ b(t+ = f: f(t) ・ h(τ-1) di This equation (3) shows that di 14 of the output signal of the above matted filter is r-O It reaches a maximum when , indicating that the width T of the input signal has been compressed to a pulse; that is, the received beam has a shape of tN,8 by the underwater detection device.

FIG. 1 shows a block diagram of one embodiment of the invention.

FIG. 2 shows a detailed view of FIG.

FIG. 3 shows an explanatory diagram of the wave receiving means used in the embodiment shown in FIG.

FIG. 4 shows a diagram for explaining the operation of the wave receiving means shown in FIG. 2.

Throughout the drawings, the same reference numerals refer to the same parts.

In Figure g1, the wave receiving means 1 is composed of, for example, an ultrasonic transducer 6 that rotates at a constant speed, as shown in Figure @3, and the signal captured thereby is sent to the mated filter 2. . Oscillator 6 with directivity of half angle 7000
is rotated around an axis 8 by a motor 7. The motor 7 is controlled by the controller 4. As shown in FIGS. 1 and 2, a signal source 9 transmitting 100 signals at a constant frequency
Assuming that the signal source is located above the vibrator 6, the vibrator 6 repeats the movement of coming into contact with the signal source, facing the signal source, and moving away again as the vibrator 6 rotates. Therefore, the frequency of the signal received by the transducer 6 changes based on the O-Doppler effect, and the distance corresponding to the central angle of 90° is determined by the transducer 6.
When moving, 1 changes as the frequency @rt changes. That is, this same wave number change is expressed by the above equation (1).

Although the configuration of the matted filter 2 will be detailed later, the structure of the matted filter 2. It is constructed to have an impulse response characteristic expressed by the above formula (2). As mentioned above, the matched filter 2 compresses all the input 1 recoded pulses that can be supplied from the vibrator 6, and sends this pulse pressure fear output to the display 3, which is expressed by the above equation (3). put out.

Ru. That is, the b1 matched filter 2 (supplies the receiving signal corresponding to the receiving beam to the receiver 3.

? I4 controller 4 is an oscillator and an output booster of this oscillator?
It consists of a control signal generator and a control signal generator. This control signal is supplied to the wave receiving means 1 and the display 3. When the 0° oscillator 6, which drives both elements in synchronization with each other, is further rotated, the receiving beam is sequentially moved to the center angle direction. The input signals formed by the receiver and captured by the receiving beam are sequentially supplied to the display 3. Table 2 3 rulers, for example composed of brown and blue; L
The display surface is scanned by the doublet beam concentrically in synchronization with the formation of the receiving beam, which is sequentially perforated in the direction of the central angle, thus providing a PPI display.

As the transducer 6 is rotated, the receiving beams are formed one after another at a false speed, and the receiving signals captured by each beam are projected to the display 3, and as a result, the underwater surrounding situation is displayed. PPI Ochojuku is displayed on the display screen of the display unit 3.

In FIG. 2, the wave receiving means 1 includes an ultrasonic transducer f1,
T9, 'r8...T4o and switches SW1, SW,
, SW8...s circuit, a switch selector 10, multipliers 11 and 12, a foil number generator 13, and an adder 14. The ultrasonic transducers T1, T9, '3, . . . r40 are arranged in a circle at equal intervals so as to constantly receive incoming signals. Minedoko T
It is sent to one input terminal of the l-counter 11 via V, , SW3, SW, -.8w9. On the other hand, the received signal captured by the transducers T9, III T6...T0n is
Switch 5vv2, SW4.3vV6 +++++
Sl'V40 k and multiplier 12 single power 1! I send out a message to the 4th child. Each switch consists of a gate,
The square waves sent from the switch selector 10 as shown in FIG.
...5Vv4o will be driven in order. switch sv
After V, is closed and half the duration of the square wave has elapsed, the received signal captured by the driver 'F' is switched to switch s.
When w, 2 passes j~, switch SW is closed, and the signal received by rL transducer 'r is sent to this switch? Passes through the calyx. When the remaining half of the square wave duration has passed,
Switch SvV is opened and switch 5v is opened instead.
Vj is closed and the received signal from the vibrator "r8 is sent to the multiplier 11.

Let it pass. However, the switch S continues to transmit the received signal from the transducer T to the paralysis device 12. When a further half of the duration of the next square wave has elapsed, switch SW2 is opened and switch 5 corresponding to oscillator 1 and 4 is opened.
Vv4 is closed. Similarly, the transducers T6, T6, T,
...'I''4° is switched between l1lN and the received signals captured by these transducers are sent to multiplier 11 or 1.
Send to 2, rl,ru. The switch selector 10 is 1jl
A square wave is generated based on the output signal of the J controller 20. The signal generator 13 operates based on the output signal of the controller 20:
4 [Figure (J]) and 180° to each other as shown in (0)
It generates two triangular wave trains having a phase difference of , and sends these signals to the other inputs of the 7'L and 1 counters 11 and 12, respectively. The d1 calculation 411 interpolates by multiplying the received signal from the vibrator with the parasitic number supplied to the - input terminal by the triangular wave (@4!SIIB) supplied to the other input terminal. The signal is sent to one input terminal of the adder 14. Fourth
As is clear from the figure, the oscillators f1, T8, T5...
・Switch SW1.8W corresponding to 'fゎ, SW,
...SW8. The switching operation is performed when the amplitude of the triangular wave is zero. Therefore, no matter how large the amplitude of noise is generated and supplied to the overhanger 11 when the switch is switched, the multiplication ≦11 produces a noise-free output signal.

Similarly, the multiplier 12 calculates the received signal from the even-numbered vibrator, the output signal of the triangular wave supplied to the other input terminal, and the output signal of the multiplier 12 by /II]. Then, it sends to the matched filter 2 an interpolated signal that is substantially equal to the signal obtained by one vibrator rotating at a constant speed and is given by the above equation (1). As will be readily understood, the multipliers 11 and 12, the signal generator 13 and the adder 14 constitute a smoothing means (!l-) for delivering an interpolated signal.

The matched filter 2 having the impulse response characteristic expressed by the above equation (2) consists of an analog delay line 15, resistors rl, r9, r3...rn, operational amplifiers 16, 17, 18, resistors R19, 8, R, Ikame, Rin. It consists of analog delay line 15
For example, the TAD-32 manufactured by E.G. Retikon, Inc. has equally spaced output terminals. A received signal from the wave receiver 1 is supplied to one input terminal of the delay line 15, and a signal from the controller 2 is supplied to the other input terminal.
A clock pulse with a zero generated is provided.

The output signal of the wave receiving means 1 is completely transferred within the delay line every time a clock pulse is supplied. delay line 1
5, received signals arriving from different directions with a central angle of 90° are stored from the right end to the left end, and therefore, a received signal 1 appears at each output terminal. The output signal appearing at the output terminal of the delay line 15 is connected to the resistors r1 and r2.
, r8, . The other input terminals of operational amplifiers 16 and 17 are grounded. The resistors 1 and 1 can be connected between the input and output terminals of operational amplifiers 16 and 17, respectively. The output terminals of the operational amplifiers 16 and 17 are connected to the input terminal of the operational amplifier 18 through resistors R5 and R6, respectively. The resistor R,11 is connected between one input terminal and the output terminal of the operational amplifier 18.

Connected between resistor 47i, R41I''i, and other input terminals and ground. The positive part of the signal is of course sampled and a signal is provided).The voltage value appearing at the output terminal of the analog delay line 15 is Vl, V, V3...
・Assuming that Vn is used, the output Eaid of the weight increaser 16 is given by the following expression.

Ea-(-!"+-"'10-"10-■' 10-=
---10”)114rl r2 r@
r4 rn Meanwhile, a signal obtained by sampling the negative polarity portion of the received signal supplied to the analog delay line 15 is supplied to the input terminal of the amplifier IIg unit 17.

The output Eb of the so-called quartet 17 is given by the following equation.

Eb-C'! 5+ v'+-"!' + V?-+
0. =9. ""'L) &r5r6r7rfirn-4 The output Ec of the operational amplifier 18 is as shown in the following equation.

&-Ea-Eb-required-+V-" + M +-
-10V-n-)Rorl r2 r@
r4+ (yJ-, -v, +y, yβ+, +Y town)
Mountain r5 r6 r7 r@rn-4 each resistor 1iff'1 of rl, r2.1"8...rn
1. , - are transported through the delay line 15 at the same speed as the transducer is switched, by reversing the direction of travel of the frequency-shifted waveform signal recorded in the delay line 15. It is determined that a waveform similar to the signal n is obtained at the output terminal of the operational amplifier 18. That is, a matched filter having an impulse response characteristic expressed by the above formula (2) was obtained. Here, the signal source is located in the θ° force direction to receive waves and movers, and from -45° to +
90W across 45° directions) Assuming that signals arriving from a wide range of directions are stored in the delay line 15,
The amplitude of the output signal of the operational amplifier 18 is very small compared to the signal value when the signal source is located in the 00 direction. That is, the output signal of the operational amplifier 18 is mainly 0
This means that the signal is arriving from the direction of 100 degrees, and a receiving beam is formed in that direction. Matsushido filter 2
The output signal is amplified and detected by an amplifier 21 and then sent to a brightness control terminal of a display 22. The polarized wave generator 23 generates a polarized wave for controlling the electron beam so that the Brownian beam is concentrically distorted within the Brownian display surface based on the output signal of the controller 20.

The incoming signal from all the signal sources is received as the frequency of the received signal changes due to the Doppler effect,
The data within the analog delay line 15 are sequentially transferred so as to reach the memory element at the right end thereof, and are recorded therein. If a single word source is located in the 00 direction with respect to the wave receiving means 1, and the received signal comes from a direction within a 90° range from 145° to +45°, then this signal source is , the transducer is further turned off, which is displayed in the 0° direction on the display surface of the display 22.
lj, selected, rinsed [The 1st signal is completely supplied to the delay line 15 and is transferred, and as a result, the oldest signal indicated in the note 1 disappears, and as a result, the 00 direction of the display 220 appears. As in 11'iT, there is no pus displayed.

If the signal W is located in the +45° direction with respect to the wave receiving means 1, and the same VLi is applied in the 90° direction from 0°, 1 at 90°! When the received signal arrives from the direction of ¥2, and is applied to the analog delay line 15, the signal source is displayed in the same direction to improve the display on the display.

One is formed almost continuously and sequentially in the direction of the central angle.

FIG. 5 shows a block diagram of a matched filter used in a practical example of the present invention.

The output signal sent from the wave receiving means 1 is supplied to an analog-to-digital converter (hereinafter referred to as "A-D converter") 50. A-D conversion'i! The output signal of the 9i50 is supplied to the output unit 51. Heavy equipment 51J: Sequentially stores signals arriving from the central angle 90 of the wave receiving means 1.

The output signal of the memory device 51 is supplied to the single-power returner of the multiplier 52.The memory device 53 has the same number of memory elements as the memory device 51, and each element has a A predetermined weight value is stored.The output signal of the storage device 53 is supplied to the other input terminal of the multiplier 52.The signals stored in the multipliers 51 and 53 are sequentially multiplied. , d is outputted in order and supplied to the multiplier 52, where the signals are combined with each other.The output signal of the multiplier 52 is sent to the accumulator 54, where it is sequentially added and accumulated.The output signal of the accumulator 54 is sent out via an amplifier 21 to a display 22-\.

Heavy equipment 51 (controlled by controller 55: hA-D
- Performs writing and reading operations of the output signal of the transformer 50. A-1) A new received signal sent from the converter 50 is stored in the memory element of the memory 51 in which the oldest received signal is stored. The read operation from the memory 51 is performed, for example, in order from the oldest signal to the newest signal. The wait signal fd stored in the memory 453 is set to im'H by the control 555 and is sequentially read out.

By switching the switch, Shirishiko's work, T7, T8...T
,,T1,T.

..., the incoming signal from the signal source that generates the constant frequency signal is received so that the frequency of the received signal changes due to the Doppler effect, and
At the D-hen J54 and 50 meetings, they are put into the memory device 51 one after another. The 1st signal source is located in the 0° direction V with respect to the wave receiving means 1.
When a signal arriving from a range direction of 90° extending from 5° to +45° is stored in the electronic device 51, this signal source is displayed in the 0° direction on the display surface of the display 22. difference,
+1-ru.

The uke and peel 1 words arriving from the 90° range direction and stored in the 3-pin storage unit 51 are read out, and in synchronization with this signal and this readout operation, the predetermined signal read out from the storage unit 53 is read out. The weight values are sequentially multiplied by a multiplier 52V and stored in an accumulator 54.

In the above example, the output signal of the accumulator 54 is I
I included the 1st signal arriving only from approximately 0° direction, and therefore a receiving beam was formed in the 0° direction. When the transducer is further switched, a new signal is input and stored with the oldest signal. As a result, no target is displayed on the display surface of the display device 22 in the 00° direction.

If the signal source is positioned in the +45° direction with respect to the wave receiving means 1, the signal received and received from the 90° direction extending from 0° to 90° is stored in the memory 51. When n is 1,
The signal sources are shown next in the same direction on the display surface of the display.

In addition, in the above embodiment, 1. : The cylinders are arranged on a circle at intervals of 9 degrees at the central angle, but if the intervals are narrower, for example 2
It is also possible to store them at intervals of ~3°. In this case, the output signal of the changeover switch is directly supplied to the A/D converter 50 without passing through the filters 11 and 12 and the adder 14.

Note that the vibrators may be arranged on a circular arc.

In addition, it is also possible to move the pendulum on two mutually parallel circles drawn on a cylinder. In this case, the The output signal is supplied to a multiplier 11, and the output signal of the impeller placed in the second field is supplied to a multiplier 12.

In the above embodiment, the one-word generator 13 generates a triangular wave, but it may also generate a sine wave or a cosine wave.

In the above practical example, the words coming from the 90° angle range are stored in the recitation 51, but the words coming from the larger angular range than 8 are stored in the recitation 51. You can also do that.

Note that it is also possible to use a plasma display or a light emitting diode array instead of a cathode ray tube as a display device.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of one column of -4.7ffl according to the present invention. FIG. 2 is a detailed view of FIG. 1. FIG. 3 is an explanatory diagram of the wave receiving means used in the centering example shown in FIG. 1. FIG. 4 is a diagram illustrating the operation of the wave receiving means shown in FIG. 2. Figure 5 shows the fruit 1 of this invention.
FIG. 2 is a block diagram of a matched filter used in a different VC. Patent applicant Koin Electric Co., Ltd.

Claims (1)

[Scope of claims] Receiving means for receiving all of the incoming signals so as to shift the frequency of the incoming signals, a matched filter for compressing the output signal t-pulses of the receiving means, and an output signal of the matched filter. a display means for displaying the information in association with the direction of arrival; In the detection device, which receives incoming waves over a wide range and displays information related to the incoming waves on a display means, the matched filter detects the output signal of the wave receiving means. an A-D converter that performs analog-to-digital conversion; a first storage unit that stores the output signal of the A-D converter; a second storage unit that stores weights; and the first storage unit. A detection device comprising: a multiplier that multiplies the output signal of the means by a weight output from the second storage means; and an accumulator that adds and stores the output signal of the multiplier.