JPH0682153B2 - Receiver for ultrasonic detection - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an ultrasonic detection receiver used in a fish finder, an active sonar, and the like.

More specifically, when converting and synthesizing received signals derived from a plurality of wave receivers, a filter having a relatively low loss and a high frequency is provided after the synthesizing to convert the signal from the transform to the synthesizing. By eliminating the need for amplification, the configuration is simplified, the device scale, circuit scale, power consumption are reduced, and the cost is reduced.

[Prior Art] Conventionally, receiving a reflected wave from a reflecting object such as an underwater target,
A detection device such as a so-called fish detection device or active sonar, which performs a detection on a reflection object by displaying the state and distance of the reflection object from the received signal on a hard copy or a CRT as an image, is widely used.

The signal processing unit between the input and the synthesis of the ultrasonic detection receiver in this type of detection apparatus will be described below with reference to FIG.

Reference numeral 2 is a wave receiver group, in which wave receivers 2a, 2b, ... 2n are arranged, and the received signals derived from the wave receivers 2a, 2b, ... , ... supplied to 6n. Here, the received signals respectively supplied are passed through matching transformers 8a, 8b, ... 8n and impedance matching buffers (buffer amplifiers) 10a, 10b ,.
b ... 12n is supplied. The phase control is performed by the mixers 12a, 12b, ... 12n with the supplied signal Osc. The signals derived here are buffers 14a, 14b, ... 14n.
, And 16n via the amplifiers 16a, 16b, ... 16n.

In the synthesis amplification unit 12, the signals from the amplifiers 16a, 16b, ... 16n are synthesized at the output connection terminals of the resistors Ra, Rb, ... Rn weighted by the Hamming function or the like, and further the buffer 20, the mechanical filter 22, and the amplifier 24 are connected. Via the output signal So.

In this way, the reception signals derived from the wave receivers 2a, 2b, ... 2n become the combined output signal So.

[Problems to be Solved by the Invention] However, in the ultrasonic detecting receiver according to the above-mentioned conventional technique, the input / phase control units 6a, 6b, ... Connected to the wave receivers 2a, 2b ,. 6n buffers 10a and 10 respectively
b ... 10n, mixers 12a, 12b, ... 12n, amplifiers 16a, 16b,
… 16n are connected. In particular, the mechanical filter 22
The amplifiers 16a, 16b, ..., 16n are required because the insertion loss in the pass frequency band is large.

This number is 504 when the receivers are arranged in a cylindrical shape of 14 stages × 36 rows, such as a 360 ° scanning sonar, which is a huge number.
In this case, 36 rows of relatively expensive mechanical filters 22 for horizontally synthesizing the wave receivers are required. further,
It is also necessary to adjust the level of 504 amplifiers 16a, 16b, ... 16n. Therefore, there is a drawback that the device scale and power consumption increase, which further increases the cost.

The present invention has been made in view of the above problems, and an object of the present invention is to simplify the configuration, scale of the device,
It is an object of the present invention to provide an ultrasonic detection receiver which has a reduced circuit size and power consumption and is excellent in cost reduction.

[Means for Solving the Problems] In order to solve the above problems, an ultrasonic detection receiver according to the present invention includes phase control and a predetermined high frequency for each received signal derived from a plurality of wave receivers. A plurality of converting means for deriving a plurality of converted signals subjected to frequency conversion to, a synthesizing means for deriving a synthesized signal obtained by synthesizing the plurality of transformed signals, and a frequency band of the predetermined high frequency in the synthesized signal. It is characterized by comprising a low-loss filter that allows passage and an amplifier that amplifies a signal derived from the filter.

[Operation] In the above configuration, the received signals derived from the plurality of wave receivers are frequency-converted and then combined. Further, for example, the output signal is derived after being amplified through a filter of relatively low loss and high frequency.

This simplifies the circuit configuration, reduces the device scale, further reduces the device weight, and reduces power consumption.

[Embodiment] Next, an embodiment of an ultrasonic detection receiver according to the present invention will be described.
The following is a detailed description with reference to the accompanying drawings.

FIG. 1 is a block diagram showing the configuration of the embodiment.

In FIG. 1, reference numeral 30 is a transducer for 360 ° scanning sonar, for example, in which 504 elements of 14 stages × 36 rows are arranged in a cylindrical shape. Here, a case will be described in which the elements of 14 stages are used as the wave receivers 32a, 32b, ... 32n and the reception signals Sa, Sb, ... Sn derived therefrom are vertically combined.

Here, reference numeral 32 is a signal processing unit, for example, a frequency 28
.. 36n having the same configuration and also serving as phase control, which are respectively supplied with the reception signals Sa, Sb, ... Sn of KHz. 36n are supplied to the frequency converters 36a, 36b, ... 36n from the outside, respectively, and matching transformers 38a, 38b ,.
For example, mixers 40a, 40b, ... 40n that perform up-conversion with a local oscillation signal Osc of 427 KHz and send a signal converted to 455 KHz are provided.

Further, it has a synthetic amplification section 41 to which the converted signals Ca, Cb, ... Cn derived from the mixers 40a, 40b ,.

The composite amplifier 41 is supplied with the conversion signals Ca, Cb, ..., Cn, and is provided with resistors R1, R2, ... Rn which are weighted by a Hamming function or the like and whose ends are connected. Further buffer 4
A ceramic filter 44 of 2,455 KHz and an amplifier 46 are connected to each other, and an output signal Os related to the vertical synthesis is derived from this. This 36-column output signal Os is derived and is supplied to a horizontal synthesizing unit (not shown).

Next, the operation of the above configuration will be described.

Received signals Sa, S derived from the wave receivers 32a, 32b, ... 32n
38n are supplied to matching transformers 38a, 38b, ... 38n for matching input impedance and the like. Then, from the matching transformers 38a, 38b, ... 38n to the mixers 40a, 40b ,.
Supplied to 0n. In addition to the phase control here,
Up-conversion is performed with the supplied local oscillation signal Osc and converted to 455 KHz, and conversion signals Ca, Cb, ...
Get Cn. The conversion signals Ca, Cb, ... Cn are resistors R1, R2,
... Rn is weighted by a well-known Hamming function or the like and is combined at the output end.

Subsequently, impedance matching is performed in the buffer 42, and a signal in a desired pass frequency band is passed through the ceramic filter 44. Further, a predetermined amplification is performed by the amplifier 46, and the output signal Os is derived therefrom.

In this case, a well-known ceramic filter 44 with a small loss and a general-purpose 455 KHz is used, and the received signals Sa, Sb, ...
38n is converted by mixers 40a, 40b, ... 40n, and further supplied via a buffer 42. Ceramic filter with pass band of 455kHz as above
Since 44 has a small insertion loss, the amplifiers 16a, 16b, ..., 16n after the mixer, which are conventionally required, are unnecessary. For example, in the case of a 360 ° scanning sonar, an amplifier facing the 504 wave receivers of 14 stages × 36 rows is not required, and the configuration is significantly simplified.

Furthermore, adjustments such as level matching of the buffer and the intermediate frequency amplifier are unnecessary, and power consumption is reduced.
Therefore, the cost is reduced. The frequency is not limited to 455 KHz and the ceramic filter in the above embodiment. The filters are resistors R1, R2,…
Any signal may be used as long as it can be amplified to a predetermined level of the amplifier 46 after the signal combined by Rn has passed and further has a desired pass band characteristic.

[Effects of the Invention] As can be understood from the above description, in the ultrasonic detection receiver of the present invention, a plurality of signals obtained by performing phase control and frequency conversion on respective reception signals derived from a plurality of receivers. A plurality of converting means for deriving the converted signal, a synthesizing means for deriving a combined signal obtained by combining the plurality of converted signals, a filter for passing a predetermined frequency band of the combined signal, and a signal derived from the filter. An amplifier for amplification is provided to convert the respective received signals derived from the plurality of receivers, which are then combined and amplified, for example via a relatively low-loss, high-frequency filter. That is, since the insertion loss of the filter is small, there is an effect that amplification between frequency conversion and synthesis is unnecessary.

As a result, the circuit configuration is simplified, the device scale is reduced, the device is further reduced in weight, and the power consumption is reduced.

In addition, it also has an advantage that the level matching required when amplification is performed is unnecessary and the manufacturing cost is reduced.

[Brief description of drawings]

FIG. 1 is a block diagram showing the configuration of an embodiment of an ultrasonic detecting receiver according to the present invention, and FIG. 2 is a block diagram showing the configuration of an ultrasonic detecting receiver according to the related art. 30 ... Transducer / receiver 32a to 32n ... Receiver 32 ... Signal processor 36a to 36n ... Frequency converter 38a to 38n ... Matching transformer 40a to 40n ... Mixer 41 ... Synthesis amplifier 42 ... Buffer 44 ... Ceramic filter 46 ... Amplifier Ca to Cn… Conversion signal R1, R2 to Rn… Resistor Os… Output signal Osc… Local oscillation signal Sa–Sn… Reception signal

Claims (1)

[Claims] 1. A plurality of conversion means for deriving a plurality of conversion signals obtained by subjecting respective reception signals derived from a plurality of wave receivers to phase control and frequency conversion to a predetermined high frequency, and the plurality of conversion signals. And a low-loss filter that passes the frequency band of the predetermined high frequency in the composite signal, and an amplifier that amplifies the signal derived from the filter. An ultrasonic detection receiver.