KR0167712B1 - Demultiplexing apparatus in telemetry data module of acoustic counter measure - Google Patents

Abstract

The present invention relates to an apparatus for demultiplexing a signal receiving unit for receiving a signal from a telemetry data module of an acoustic counter measure by detecting an acoustic signal 2 in water and detecting an exact position of an acoustic source. will be.

The demultiplexing apparatus of the acoustic counter system signal receiver comprises a frame latch, a frame sync detector, a counter / timing logic, and a demultiplexer. The signal received from the bipolar / unipolar signal converter of the signal receiver is a frame signal (eg, Frame signal (FAS) is stored by dividing FAS) and channel data, and channel data is transmitted to the demultiplexer, and the demultiplexer divides the transmitted 12-bit contiguous data into one channel data, and then stores the channel address, data, and strobe. Demultiplex by outputting together.

Description

Demultiplexing unit of signal counter of sound counter system

1 is an exemplary configuration block diagram showing an acoustic counter system.

2 is a block diagram showing in detail the vibration isolation module and the sound module of FIG.

3 is a block diagram showing in detail the signal transmission module of FIG.

4 is a block diagram showing in detail a signal receiving unit including the demultiplexing apparatus of the present invention.

5 is a structural block diagram of the present invention.

* Explanation of symbols for main parts of the drawings

10: equalizer 20: automatic gain adjustment vaporizer

30: bipolar / monopolar conversion means 40: clock reproducing apparatus

41: LC tank circuit 42: line receiver

50 demultiplexer 51 frame latch

52: frame sync detector 53: counter / timing logic

54: Demultiplexer 100: Ship

110: data processing unit 120: signal receiving unit

200: towing cable 300: sound sensor

310: vibration isolation module 311: tension sensor

312: buffer 320: signal transmission module

321A, 321B, 321C: Analog Multiplexer Section

322A, 322B, 322C: Digital Multiplexer / Driver Section

330: sound module 331: hydrophone

332: preamplifier 333: protection circuit

334 Seawater noise compensation circuit 335,336 Roll sensor

337: depth sensor 338: orientation sensor

340: tail rope assembly

The present invention receives the signal transmitted by the Signal Transmission Module (Acoustic Counter Measure) of the acoustic counter measure to detect the sound of the underwater sound, such as the exact position of the sound source, reproduced without distortion and serial data received The demultiplexer of the signal receiver which demultiplexes the data into 36 parallel channel data.

In general, the acoustic countermeasure system that detects the acoustic signal in the water and detects the exact location of the sound source detects the acoustic wave, which is fixed to the vessel to install the acoustic sensor unit on the vessel and subsea to the acoustic sensor installed on the sea floor; There is a towing doll that connects to the ship with a towing cable.

The towed acoustic counter module (Towed Acoustic Counter Module) detects the acoustic signal in the water as shown in FIG. 1, converts it into an electrical analog signal, converts it into a digital signal and multiplexes it to the signal receiver 120 A towing cable 200 for connecting the acoustic sensor unit 300 to be transmitted, the acoustic sensor unit 300 in the ship and the underwater, and the electrical signal received from the acoustic sensor unit 300 data processing unit in the vessel 100 The signal receiver 120 and the data processor 110 for classifying, searching and processing data received from the signal receiver 120 are provided.

In addition, the acoustic sensor unit 300 includes a vibration isolation module 310 for attenuating initial vibration, a signal transmission module 320 for converting an input analog signal into a digital signal, and transmitting an acoustic signal. A sound module 330, and the tail rope assembly 340 to attenuate the vibration finally.

Hereinafter, the operation of the acoustic sensor unit 300 will be described in detail with reference to FIGS. 2 and 3.

The acoustic module 330 is underwater. This module is a module that receives sea sound and converts it into an electrical signal and removes seawater noise flowing through the signal. A hydrophone (331) that receives underwater sound and converts it into an electric signal, and amplifies a fine signal Pre-amplifier (Pre-Amp: 332), protection circuit to protect the hydrophone (331) from overcurrent (Input Protector: 333), and roll sensor (Roll Sensor: 335,336) to detect the inclination of the acoustic sensor unit 330 And, the sea noise correction circuit (Sea Noise Correction Amp: 334) to compensate for the noise caused by sea water, the depth sensor 337 for measuring the depth of the acoustic sensor unit 330, and the orientation of the acoustic sensor unit 330 It consists of the orientation sensor 338 to measure.

The hydrophone 331 and the preamplifier 332 are divided into three groups at 120 ° intervals in one package, and since 32 such packages are arranged, each group has 32 channels.

Underwater acoustics are propagated by the mechanical coarse action of seawater particles, and the vibration causes a volume change in the hydrophone 331 with a magnitude proportional to the product of the square of the frequency and amplitude, thereby causing the hydrophone 331 to transmit an electrical energy signal. Occurs.

The electrical energy signal is expressed in the form of current and voltage. Impedance coupling considering the sensitivity with the output preamplifier 332 of the hydrophone 331 may transmit the signal of the hydrophone 331 farther.

The preamplifier 332 amplifies the weak signal of the output terminal of the hydrophone 331, and processes the small signal of the hydrophone 331 after the emphasis process to compensate for the attenuation according to the progress of the sound wave. To easily amplify.

The emphasis refers to a pre-emphasis that changes a signal to generate a high frequency spread and a de-emphasis that extends a low frequency component as compared to a high frequency. Signal To Noise Ratio (SNR) is increased.

In more detail, a signal in which most energy exists in a low frequency region such as sound waves does not generate a large frequency deviation due to a high frequency component of the same magnitude.

Therefore, the energy of the signal is not uniformly distributed over the allocated bandwidth, but the energy of the high frequency portion is less distributed, which results in a weak signal-to-noise ratio for the high frequency signal.

Pre-emphasis and de-emphasis methods to overcome these weaknesses have high signal level and noise can be suppressed to some extent in the transmitter. Intentionally changing, the signal level is high in the receiver and noise can be suppressed to some extent, so that the signal to be demodulated is intentionally changed by extending the low frequency compared to the high frequency.

When the signal is amplified by the preamplifier 332, the noise is also amplified together in the signal, thereby limiting the amplification circuit bandwidth of the preamplifier 332 in consideration of the removal of the noise factor itself as well as the surrounding noise. It is decreasing.

The amplification element itself includes noise generated by the amplifying element, 1 / f noise, shot noise, and Johnson noise, which occur in the low pass filter frequency band, and 1 / f noise occurs in the low pass band, and Johnson noise, Shot noise is called white noise because it appears above the frequency modulation band and is uniformly distributed in the frequency band.

As the signal processed as described above passes through the sea noise compensation circuit 334, the noise signal in the sea water existing in the low frequency region is blocked, and the attenuated high frequency component signal is compensated and transmitted to the signal transmission module 320.

In addition, the depth sensor 337 and the orientation sensor 338 of the acoustic module 330 measure the azimuth and depth information, which are examples of the acoustic sensor unit 300, and transmit the measured orientation and depth information to the signal transmission module 320.

The signal transmission module 320 is divided into three groups A, B, and C, and each group is an analog multiplexer including current / voltage conversion means (I / V CONV), an analog multiplexer (AMUX), and a gain amplifier (Gain Amp). Part 321A, 321B, 321C, Analog / Digital Converter (A / D CON), EPLDI (Erasable Programmable Logic Device 1), EPLD2, Unipolar / Bipolar Conversion Means (U / B CONV) ) And a digital multiplexer / driver section 322A, 322B, 322C, which is a line driver LDRV.

The 32 analog sound sensor signals and 4 auxiliary sensor signals transmitted to each group A, B, and C of the signal transmission module 320 in the form of a current in the sound module 330 are current / voltage conversion means (I / V CONV). Is converted into a voltage form, and the converted signal is used as an analog multiplexer (AMUX) by using the GR and CA signals generated by EPLD2 of the digital multiplexer / drivers 322A, 322B, and 322C as control signals. It is sampled and multiplexed at 15.36KHz) interval and output to Gain Amp.

The gain amplifier (Gain Amp) is amplified by a constant gain of the 32-channel (CHI-CH32) of the signals sequentially output from the analog multiplexer (AMUX) and the auxiliary sensor signal of the 4 channels (CH33-CH36) It outputs to the analog-to-digital converter (A / D CON) of the digital multiplexer / driver section (3? 3A, 322B, 322C) without amplification.

The analog-to-digital converter (A / D CON) receives the conversion signal generated by EPLD2 and converts the signal transmitted from the gain amplification unit (Gain Amp) into a 12-bit digital signal and outputs it to EPLD1.

The EPLD1 converts an input digital signal into 12-bit parallel data, and then digitally multiplexes the serial data, and divides the frame signal (FAS) and the inverted frame signal (PAS inversion) to distinguish each group signal and 36 channel signals in the group. Are inserted into the beginning of the channel data alternately, and then line-coded (eg, HDB3, AMI) and output.

Unipolar / bipolar conversion means (U / B CONV) converts line-coded monopolar signals into bipolar signals, which are advantageous for transmission lines, and outputs them to the line driver (LDRV), which transmits signals before transmitting the signals. In order to prevent the loss during power up, power up and then output.

The serial data processed as described above is a vibration that buffers the vibration sensed in the buffer 312 by detecting the attenuation of the vibration generated from the towing cable and the towing cable and the vibration caused by the towing by the tension sensor 311. It is transmitted to the signal receiving unit 120 installed on the vessel 100 of the ship via the isolation module 310 via the towing cable 200.

In the signal transmission of the signal transmission module 320 as described above, the circuits of the three groups are synchronized by the clock receivers CLK REV of the groups A and C receiving the synchronous clock generated by the clock generator CLK GEN of the group B. It is controlled by timing signals, control signals, conversion signals, and frame time slots generated by EPLD2.

The signal receiver 120 includes an equalizer 10, an automatic gain adjustment amplifier 20 for automatically amplifying the received series of signals, and amplifying the output level constantly, and the bipolar / unipolar conversion means 30. And a clock reproducing apparatus 40 for reproducing a clock for processing data converted into unipolarity.

The signal receiver 120 reproduces the distortion of the received signal, amplifies it to a predetermined level, converts the bipolar signal into a unipolar signal, and then converts it into nonreturn-to-zero (NRZ) data, thereby making a meaningless binary pulse in the data. ) To play only pure data.

However, since the data is 36 channel serial data, it is necessary to demultiplex the data into a parallel channel of 36 channels which is easily processed by the data processor 110.

Accordingly, an object of the present invention is to provide an apparatus for demultiplexing a signal received by the signal receiving unit 120 into 36 channels of parallel data.

The configuration of the present invention stores frame signals in the input data provided by the bipolar / unipolar conversion means 40 of the signal receiver 120 as shown in FIGS. 4 and 5, and the other data is stored in a demultiplexer (54). Synchronize all the counters of the Counter / Timing Logic (53) with the frame to generate a Frame Latch (51) to transmit and to generate a suitable timing signal for detecting frame synchronization and demultiplexing the data stream. Frame Synchronous Detector (52), counter / timing logic (53) to make the timing required for demultiplexing, and 12-bit continuous data are divided into one channel of data, and stored as channel address, data, strobe and The demultiplexer 54 outputs by demultiplexing together.

Referring to the operation of the present invention.

In the demultiplexing device 50, the bipolar / unipolar conversion means 40 of the signal receiver 120 is converted into a unipolar signal, and then converted into NRZ data, and then decoded line coded data to make a meaningless binary pulse in the data ( When the pure data without the binary pulse is applied, the frame latch 51 stores the frame signal FAS by dividing the frame signal FAS and the channel data among the input data and transmits the channel data to the demultiplexer 54. .

The demultiplexer 54 divides the transmitted 12-bit contiguous data into data of one channel, demultiplexes the channel data, the strobe, and outputs the data.

This demultiplexing of the demultiplexer 54 is such that the frame synchronization detector 52 synchronizes the bit counter, channel counter, and group counter of the counter / timing logic 53 with the frame signal FAS, and the counter / timing and logic 53 By providing the timing necessary for demultiplexing.

In addition, the frame synchronization detector 52 performs a synchronization detection cycle considering that the synchronization signal is out of synch when the third consecutive frame signal FAS is wrong, and is synchronized when the fourth continuous frame signal FAS coincides with the out of synch status. see.

The counters of the counter / timing logic 53 count again when out of sync.

The present invention has an effect of facilitating data processing of the data processing unit 110 by demultiplexing and outputting a series of signals received by the bipolar / unipolar conversion means of the signal receiving unit into respective channel data.

Claims (1)

In order to detect the exact location of the sound source, audible sound is detected by a plurality of channels at each location spaced at a predetermined angle, and the sound depth and azimuth data measured at each location are separately added to the channel data detected at each location. As a device for receiving and demultiplexing the serial data signal transmitted from the signal transmission module 320 of the sound opposing system, which is included as channel data and converted into a serial data signal, and outputs the signal. And a frame latch 51 for separating a frame signal for distinguishing groups from the received serial data signals and extracting channel data for each group, and serial data for each channel of a predetermined bit input from the frame latch 51. Is stored as data of one channel, and demultiplexed together with channel address, data, and strobe signal A frame synchronization detector 52 that detects and outputs frame synchronization based on the demultiplexer 54, a frame signal of the frame latch 51, and a reference applied to the frame synchronization signal of the frame synchronization detector 52. Demultiplexing by parallel data of a predetermined channel through the demultiplexer 50 including a counter / timing logic 53 for supplying the timing required for demultiplexing to the demultiplexer 54 based on a clock A demultiplexing device of an acoustic opposing system signal receiver.