JPS58117472A - Signal record reproducer - Google Patents

Abstract

PURPOSE:To reduce bearing diviation in reproduced images due to uneven travelling of a magnetic medium by recording or reproducing a bearing signal synchronizing a video signal employing an audio track thereof. CONSTITUTION:A video signal V1 and a synchronous trigger signal T1 from a radar 201 are quantitized gradually with a first A/D converter 202 and fed to a first memory circuit 203. A radar signal memorized in the circuit 203 is read out according to a control signal from a reading address generation circuit 206 and applied to a mixing amplifier 208. Then, the radar signal is mixed with a VD signal with the mixing amplifier 208 and a mixed signal is converted into an analog signal adjusted in the level to the input specification of a video track of a magnetic recorder/reproducer 211 with a D/A converter 210 and recorded thereon 211, that is, on a commercial VTR.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a signal recording and reproducing apparatus that records a video signal such as a radar signal on a magnetic medium and reproduces the recorded signal.

Conventionally, in this horizontal signal recording/reproducing device, a video signal from a radar device or the like and its synchronization trigger signal were mixed as analog signals and recorded on a video track of a magnetic medium.

However, in such conventional signal recording and reproducing devices, the video signal of radar etc. is a wide band signal of 15 to 29 MHz @ variable, and the video band of a commercially available television video recorder (hereinafter referred to as VT l (,)) is is 3~4MH
z l, so it cannot be connected and used as is. Additionally, in general, when recording and playing back on a VTR, a pulse signal equivalent to the vertical synchronization signal of a television, called a VD scratch signal, must be mixed with the input signal to the video track to run the magnetic medium and drive the recording/playback head in synchronization. . However, it is not possible to record the video signal that is intended to be recorded by a device related to VDA/f pulses (1/60 second period, pulse width of several hundred micrometers), such as radar, or by using advanced signal synthesis methods, the video signal and VD scratch signal cannot be recorded. Even when a method of mixing and recording and separating during playback was used, the synchronization of the VTR was unstable and playback IiIigI was disturbed. Therefore, a particularly expensive broadband magnetic configuration reproducing device was required.

The present invention has been made in view of these conventional problems.In recent years, it has become possible to configure inexpensive, large-capacity digital storage circuits. stored in a digital storage circuit over a plurality of included sweep cycles;
The purpose is to solve the above problems by continuously generating video signals at low speed during the next VD signal cycle, compressing the band of the video signal, and recording and reproducing the video signal as a trigger signal and video signal synchronized with the VD scratch signal. The outline of the present invention will now be explained using radar as an example.

In pulse circuit theory, it is known that the pass frequency bandwidth B of the circuit is inversely proportional to the pulse width τ of the signal, and 13
=A/f. (However, A is a constant). PPI
In the case of a display radar, in the case of a short-distance display range (3?I ri or less), a transmission pulse with a pulse width of about 0.08 .mu.s and a repetition period of 250 to 300 .mu.s is generally used. In this case, the video band of the receiving system is 15 to 20 M)
Requires 1K bandwidth. If this video signal is quantized with a sampling clock period τl and stored in a digital storage circuit, and is read out with a readout clock period - and the relationship τ2-n- holds true, the pulse width of the successively output signal is is multiplied by a, and the bandwidth is approximately compressed to l/n. However, the time width of the entire signal becomes n times larger.

Now - as an example, to display the received PgI up to 3 seconds, the time of radio wave propagation is to save the transmitted pulse from the 31st time.
+ time is required. If this is band compressed using the relationship ττ2 = 5 x τ, the video display time width of 3 nautical miles will be approximately 1
85 μ-, which is a repetition period of 250 to 300
jIm is sufficiently large, so that the band of all signals necessary for display can be compressed to 3 to 4 MHz. Also,
By synchronizing the timing of continuous output from the storage circuit with the VD flaw signal of the VTR, the VD flaw signal video signals can be mixed without temporally overlapping, and separation during playback can be easily performed. During playback, the separated video signal is sampled at a clock cycle τ2 opposite to that during recording, quantized, and stored in the storage circuit. If the video signal is read from the storage circuit at the clock cycle T□, the video signal returns to the original time system, and if this is supplied to the reproduction radar indicator, the radar image received during recording can be almost faithfully reproduced.

On the other hand, in the case of long-distance range, for example, at a 120s Ri-marked fort,
When the pulse repetition period is 2 ms, the time width of the signal required for display is about 1.5 ms, and the idle time for band compression is about 95 m5. However, in the case of a long distance range, the transmission pulse width is generally about ljs, so the bandwidth originally required for radar video signals is 2 to 3M.
Since the frequency is Hz, the band compression ratio may be 1.

Therefore, if the ratio of the clock cycle r to 1 is appropriately selected in accordance with the display range, the VT
Synchronized with R's VD signal. A video signal with a video bandwidth of 3 to 4 MHz or less can be obtained.

Based on the above principle, VT, which is a video bandwidth of 3 to 4 MHz,
Broadband radar video signals can be recorded and reproduced on video tracks of magnetic media using R.

#! In Figure 1, (2) is the synchronization trigger signal, the plow is the video signal, and the oki is the synchronization signal of the magnetic recording and reproducing device (hereinafter referred to as VD (VD)).
? signal) and the signal 4 when these signals are mixed.
The waveform is shown in D.

Although all the signals in this figure are shown as having negative polarity, the present invention is not limited to the polarity of the signals.

Hereinafter, the present invention will be explained based on the drawings. FIG. 2 is a diagram showing an embodiment of the present invention. In the same figure, 201
is the radar device, 2o2 is the first A-DfJ device, 203 is the JIII memory circuit, ? 204 is a first write address generation circuit, 2o5 is a first clock generation circuit, 2o6 is a first read address generation circuit, 2o7 is a second clock generation circuit, 208 is a mixing amplifier, 2o9 is a VD signal generator, 21o is a first DA converter, 211 is a magnetic recording/reproducing device, 212 is a signal separator, 213 is a second AD converter, 214 is a third storage circuit, 215 is a #I2 write address generation circuit, 216 217 is the second DA converter; 218 is the signal component j
219 is a reproducing radar indicator, 220 is an A-D converter, 221 is a 1g2 storage circuit, 222 is a parallel/serial converter, 223 is a serial/parallel converter, 224 is a fourth storage circuit, 225 is a D-, 8 converter, 226 is a digital azimuth signal output terminal, and 227 is a digital signal output terminal.

Next, the operation of the above embodiment will be explained.

In FIG. 2 1, the video signal from the radar device 201 ■
1 and the synchronized trigger signal T1 is @1's A-1) converter 202
The signal is sequentially quantized and supplied to the first memory -'1IIr203. At the same time, the synchronization trigger signal T1 is supplied to the first write address generation circuit 2041 with the start information t=of the write period, and a signal with a clock period of □ generated by the first clock generation circuit 205 is supplied to the first write address generation circuit 2041. :By supplying the converter 202 and the write address circuit 204, the trigger signal TI and the video signal vl (hereinafter referred to as radar signal) are sent to the first storage circuit 20 according to the insertion period i□.
3 is stored. The radar signal stored in this first storage circuit 263 is read out by the control signal from the read address generation circuit wI 206, and the mixed increase 11! 208. At this time, the successive address generation circuit 206
Since it is controlled by the clock cycle τ2 generated by the clock generation circuit 207, the first memory circuit 203 is only τ,/1° more than the first memory circuit 203. It is a band-compressed signal. Here, the first storage circuit 203 stores data over the synchronization trigger period of the double image within the Ml)@ period time (for example, over 67 periods of the trigger period of 25011 s out of the VD period of 16.7 m5 (reciprocal of 60 Hz)). It is composed of reciprocals (for example, two sets) of circuits with capacitance. Then, VD (i!) is sent to the write address generation circuit 20 by the VD signal of the signal generator 209.
4 and the addresses generated by the read address generation circuit 206 are switched and controlled every cycle of each VD signal, so that when information is written to one memory circuit, information is read from the other memory circuit at the same time. Therefore, the radar signal can be synchronized with the VD signal without being dropped. This radar signal is mixed with the VD signal in a mixing amplifier 208, and this mixed signal is sent to a first DA converter 210.
The signal is converted into an analog signal whose level is adjusted according to the input specifications of the video track of the magnetic recording/reproducing device 211, and is recorded in the magnetic recording/reproducing device 211. That is, commercially available V
This means that it was recorded in T-box.

During playback, video track 2 of the magnetic recording/playback device 211
The mixed signal taken out from 111 is passed through a signal separator 212 using a separation method based on pulse width and amplitude discrimination.
It is separated into a D-fold signal radar signal. The radar signal is converted into a digital signal by the second A-D converter 213 and then sent to the third A-D converter 213.
The data is supplied to the memory circuit 214 of the memory circuit 214, and is stored by the address generated by the write address generation circuit 215 of the memory 2. At this time, the AD converter 213 and the write address generation circuit 215 are controlled by the clock cycle -, and the start information of the write cycle is given by the synchronization trigger signal T2 detected by the signal separator 212.

The information read from the third storage circuit 214 at the address generated by the second read address generation circuit 216, ie, the radar signal, is applied to the second DA converter 217. Here, the second read address generation circuit 216 and the second D-A
Since the converter 217 is controlled by the clock period τl, D
- It becomes an A-transformed and expanded signal, and has the same time system as the original signal. The radar signal that has become an analog signal is sent to the signal divider S unit 21
8, the signal is amplitude-separated into a trigger signal T3 and a video signal 3 that are faithful to the original signal when the received signal was recorded, and are supplied to the radar indicator 219 for reproduction, respectively. Furthermore, in FIG. 2, the direction signal from the radar device 201 is simultaneously recorded on the audio track of the magnetic recording and reproducing device,
An example of regeneration is also shown.

Orientation signal A1 from the radar device 201 (generally,
8-D (often a synchro signal) is a synchro signal.
In the digital) converter 220, the synchronous trigger signal T
1, is converted into a parallel digital direction signal,
Write address generation circuit 204 with a clock period of -
is temporarily stored in the second storage circuit 221. Then, it is read out from the second storage circuit 221 by the read address generation circuit 206 synchronized with clock cycle 1 and applied to the parallel-to-serial converter 222. The azimuth signal, which is controlled by the same clock cycle and converted into a serial digital signal, is recorded on the audio track 211b of the magnetic recording/reproducing device 211. Since the audio track 211b of the magnetic recording and reproducing device is recorded and reproduced in synchronization with the video track 211a, the synchronization relationship between the video signal recorded on the video track and the direction signal recorded on the audio track is maintained.

During playback, the serial digital azimuth signal taken out from the audio track 211b of the magnetic recording/playback device 211 is converted into a signal component @'421 by the serial-parallel converter 223.
It is controlled by the trigger signal T2 separated by 2 and the clock cycle and converted into a parallel digital signal. This parallel digital direction signal is sent to the 20th write address generation circuit 2151.
Under this control, the second
The read address is read out by a control signal from the read address generation circuit 216. The parallel digital azimuth signal thus read out in synchronization with the video signal is converted into a synchronized signal by a DS (digital synchronized) converter 225 and supplied to the reproduction radar indicator 219.

In FIG. 2, a digital radar signal output terminal 227 and a digital azimuth signal output terminal 226 are provided for convenience when reproducing with a digital signal input device such as a collision prevention device.

FIG. 3 shows another embodiment.

The difference between the embodiment shown in FIG. 2 and the embodiment shown in FIG. 2 is that the azimuth signal is recorded and reproduced using the video track of the magnetic medium in the same way as the video signal. This is used when it is desired to use the audio track of the magnetic recording/reproducing device for recording other signals such as audio, or when it is desired to improve the synchronization between radar signals and azimuth signals.

That is, in the first embodiment shown in FIG.
It is possible to read out the vD flaw signal of R, synchronously and record it in a video channel of the magnetic recording/reproducing device in a time-division manner along with the TV synchronization signal VD, radar trigger signal, and radar video signal.

In FIG. 3, the first successive address generation path 206 is connected to the first storage circuit 203') which generates a video signal read address for the period, and then passes the azimuth signal successive address to the second storage circuit 221. occurs. For this reason, the parallel digital azimuth signal is successively output from the ml storage wlI 221 with a certain time delay after the second video signal and is applied to the parallel-to-series converter 222. The orientation signal converted into a serial digital signal in this converter 222 is therefore applied to the mixing amplifier 6208 without being temporally superimposed with the video signal. Therefore, the output of the mixing amplifier 208 becomes a mixed signal that is time-divided into the Vi) signal, the radar signal (including the radar video signal and the trigger signal), and the radar azimuth signal. and recorded on the video track 211 of the magnetic recording/reproducing device.

During playback, the signal separator 212 separates the VD flaw signal into the trigger signal T2, video signal v2, and direction signals A2, A-D.
The signal is converted into a digital signal by a converter 213 and applied to a gate circuit 302, which separates the trigger signal and video signal into a third storage circuit, and the azimuth signal into a serial-parallel converter 223.

That is, since the timing circuit 1 synchronized with the trigger signal T2 and the clock signal τ2 supplies a fixed time delay gate control signal to the gate circuit 30, the serial digital azimuth signal is supplied to the serial-parallel converter 223. be done.

The azimuth signal converted into a parallel digital signal by the serial-to-serial converter 223 is stored in the fourth storage circuit 224, read out by the read address generation circuit 216 in synchronization with the video signal, and then converted by the DSf converter 225. It is converted into a synchro signal and supplied to the reproduction radar indicator 219.

FIG. 4 shows a magnetic recording/reproducing device 2 in the embodiment shown in FIG.
11 shows the waveform of a mixed signal recorded on 11 video tracks. 184, in one trigger period, 401 is the time occupied by the video signal necessary for displaying the range, and 402 is the time occupied by the serial digital azimuth signal.

Further, 403 is a delay time from the trigger signal to generation of the direction signal. FIG. 5 shows a first A-D converter 202, an Ml storage circuit 203, a first write address generation circuit 204, and a first read address generation circuit 206 used for recording in the embodiment of FIG. and 11g1 D-A converter 210, a second A-D converter used during reproduction, a third storage circuit, a second write address generation circuit, a second successive address generation circuit, and a second An embodiment will be shown in which the DA converter is shared with the DA converter. That is, in the figure, this is realized by providing a first switch S1, a second switch, a switch output of gg3, a fourth switch 6, and a switch output of wJ5.

Further, in the same figure, each of the above-mentioned switching devices is shown in the set state at the time of recording, and it is sufficient to switch all of them to the open position shown in the figure at the time of playback.

Furthermore, in the embodiment shown in FIG. 3, it is clear that by providing a switch, a considerable amount of circuitry is shared and circuit savings are achieved, but the details can be easily assumed from the embodiment shown in FIG. For this reason, the drawings have been omitted.

Generally, when video signals from radar or the like are recorded on a magnetic medium, they are not played back at the same time.

Further, the operations of the above-mentioned sections are the same during recording and during playback, except that the control clock period n and τ2 are in an opposite relationship. Therefore, by switching the control clocks and input/output signals of each of the above sections according to recording or reproduction, each of the above sections can be shared, and the number of elements can be saved.

This has the effect of making a sophisticated device smaller and lighter.

As explained above, according to the present invention, commercially available VTR
By using a wideband video signal such as radar, it is possible to record and reproduce a wideband video signal from a commercially available VTR or other magnetic medium recording/reproducing device having a narrowband characteristic.

(b) It is possible to synchronize the synchronization signal of a commercially available VTR etc. with the video signal of a radar etc. which is originally asynchronous.
A commercially available VTR can be used without any special modification.

(c) In the first embodiment, since the azimuth signal is recorded in synchronization with the video signal ζ using the audio track of the magnetic medium, it is possible to reduce the azimuth deviation of the reproduced image due to uneven running of the magnetic medium.

2) In the second embodiment, the direction signal can also be recorded and reproduced on the video track of the magnetic medium by time division.
In addition to further stabilizing the direction accuracy of MgI, adding signals other than the Eirin signal to the audio track (for example, 1 error condition,
information such as date, time, location, etc.) can be recorded.

(e) In the third embodiment, a detailed explanation was given using a radar as an example, which can realize an economical device without reducing the above-mentioned effects. It can be used in any device that displays a video signal by beam scanning the transmitted pulse and a video signal by transmitting a transmitted pulse and receiving the reflected signal, such as sonar, medical diagnostic equipment, etc. Wide range and convenient.

[Brief explanation of drawings]

FIG. 1 is a waveform diagram showing the mixture of the radar signal and the synchronization signal,
2 is a system diagram showing the first embodiment of the present invention, FIG. 3 is a system diagram showing the second embodiment, FIG. 4 is a waveform diagram of the mixed signal in the embodiment of FIG. 3, and FIG. The figure is a system diagram showing the third embodiment.

Claims (4)

[Claims] (1) A video signal obtained by transmitting pulsed energy from a transmitter in a specific direction in synchronization with a periodic trigger signal and receiving the reflected signal is transmitted to the first A-1.
) The converter sequentially stores the stored data and stores the stored data together with the trigger signal over a plurality of trigger cycles.
A second storage circuit that quantizes the transmitted azimuth signal and stores the azimuth signal at the time of generation of the trigger signal, and a second storage circuit that quantizes the transmitted azimuth signal and outputs the trigger signal and video from the first storage circuit. means for compressing the band of stored information using a successive clock signal slower than the write clock signal when reading the signal; and a synchronization signal of the magnetic recording and reproducing device when reading the stored information from the first storage circuit; means for time-divisionally mixing the trigger signal and the video signal over the plurality of trigger periods by reading them synchronously; and a first D for converting the mixed signal into an analog signal.
- A converter and the converted analog signal are recorded on a video track of the magnetic recording and reproducing device capable of recording and reproducing using a magnetic medium, and the video track and the converted analog signal are recorded on the video track of the magnetic recording and reproducing device. The transmission azimuth signals read out from the second storage circuit are simultaneously recorded on a synchronized audio track, and when the signals are reproduced from the magnetic recording/reproducing device, a means for separating the mixed signals and a signal separated by the separating means are provided. a third storage circuit for quantizing and storing a trigger signal and a video signal, which are band compression signals, by a second A-D converter; and a third storage circuit for storing a transmission azimuth signal read from an audio track of the magnetic recording/reproducing device. When reading the band-compressed signal from the storage circuit No. 4 and the third storage circuit,
means for band-expanding the storage information using a clock signal faster than the write clock signal; and a second D-A converter for converting the band-expanded information output from the third storage circuit into an analog signal. and a trigger signal almost faithful to the original signal received by the reflected signal No. 16 and a video signal synchronized therewith can be reproduced, and at the same time, the transmitted azimuth signal can also be read out from the fourth storage circuit. A signal recording and reproducing device characterized by: (2) A video signal obtained by transmitting pulsed energy in a specific direction from a transmitting tank in synchronization with a periodic trigger signal and receiving the reflected signal and a sequential quantum a first storage circuit that quantizes the transmitted azimuth signal and stores it together with the trigger signal over a plurality of trigger cycles; means for compressing the band of stored information using a read clock signal slower than a write clock signal when reading a trigger signal and a video signal from the second storage circuit and the first storage circuit; When reading stored information from the circuit and the second storage circuit, the synchronization signal of the magnetic recording and reproducing device,
Means for simultaneously dividing and mixing the respective signals by synchronously reading out the trigger signal, the video signal, and the transmitted azimuth signal over the plurality of trigger periods; and a means for converting the mixed signal into an analog signal. 1 D
- A converter and the converted analog signal are recorded on a video track of the magnetic recording/reproducing device which can be externally recorded on a magnetic medium, and the mixed signals read from the magnetic recording/reproducing device during reproduction are separated respectively. A trigger signal, a video signal, and a transmission direction signal, which are band-compressed signals separated by the separating means, are sent to A- of the IF5.
a third storage circuit that stores a trigger signal and a video signal quantized by a D converter and separated via a gate circuit; a fourth storage circuit that stores another separated transmission azimuth signal; means for band-expanding the band-compressed signal of the stored information using a clock signal faster than the write clock signal when outputting the band-compressed signal from the storage circuit of the third storage circuit; a second 1)-A converter that converts the received information into an analog signal, and reproduces a trigger signal that is almost faithful to the original signal received from the reflected signal and a video signal synchronized therewith; 11
4. A signal recording and reproducing device characterized in that a transmitted azimuth signal is also output from the storage circuit of No. 4 at the same time. (3) A video signal obtained by transmitting pulsed energy from a transmitter in a specific direction in synchronization with a periodic trigger signal and receiving the reflected signal is converted from analog to digital via the first switch. a first storage circuit that sequentially quantizes the azimuth signal and stores it together with the trigger signal over a plurality of trigger cycles; a second storage circuit that stores the azimuth signal of the azimuth signal via a second switch; and a second storage circuit that stores the azimuth signal using a read clock signal that is slower than the write clock signal when reading the trigger signal and the video signal from the first storage circuit. When reading information from the first storage circuit, the trigger signal and the video signal over the plurality of trigger periods are synchronized with the first period signal of the magnetic recording and reproducing device. a D-large converter that converts the mixed signal into an analog signal via a third switch, and a fourth switch that converts the converted analog signal into a fourth switch. The second audio track is recorded on the video track of the magnetic recording and reproducing device that can record and reproduce information on a magnetic medium through a device, and the second When simultaneously recording the transmitted azimuth signals read from the storage circuit through the fifth switch and reproducing the information from the magnetic record 1# reproducing device, the number is
, by switching the fourth and fifth switching devices to AW the means for separating the reproduced mixed signals, respectively, and switching the trigger signal and the video signal, which are band-compressed signals separated by the separating means. The azimuth signal is quantized by the A-D converter and stored in the first storage circuit through the first switching device, and the transmitted azimuth signal output from the todio track of the magnetic recording and reproducing device is switched. #! via the second switch! The source signal received by storing the signal in the memory circuit of 2 and supplying it to the above-mentioned 1)-A converter, converting it to an analog signal, and taking it out via the fourth switch whose output from the converter is switched. The bird that is almost faithful to the signal reproduces the signal and the video signal synchronized therewith, and simultaneously reads out the transmitted azimuth signal from the second storage circuit via the fifth switch. Characteristic signal recording and reproducing device. (4) Send 1 in synchronization with the periodic trigger signal! The video signal obtained by transmitting pulsed energy in a specific direction from the machine and receiving the reflected signal is sequentially quantized by an A-D converter via a first switch, and is quantized by a plurality of triggers. Quantizing the transmitted azimuth signal with the @l storage circuit that the bird stores together with the signal over a plurality of trigger periods, and storing the azimuth signal at the time of generation of the trigger signal via a second switch. means for compressing the band of stored information using a successive clock signal slower than a write clock signal when reading a trigger signal and a video signal from the second storage circuit and the first storage circuit; When reading memory information from the memory open circuit and the second memory circuit, the synchronization signal of the magnetic recording and reproducing device,
A D-A converter that converts the trigger signal, the video signal, and the transmitted azimuth signal over the plurality of trigger cycles into an analog signal by synchronizing them, and a fourth switch that converts the converted analog signal into an analog signal. the first, second, third and fourth switching devices when recording information on a video track of the magnetic recording and reproducing device capable of recording and reproducing information via a magnetic medium and reproducing information from the magnetic recording and reproducing device; A means for separating the mixed signals successively produced during reproduction by switching the trigger signal, a video signal, and a transmission azimuth signal, which are band-compressed signals separated by the separating means, through a first switch. A trigger signal and a video signal quantized by the A-D converter and separated via a gate circuit are stored in the first storage circuit, and another separated transmission azimuth signal is switched to a second one. A clock signal faster than the write clock signal is used to expand the band of the stored information when the band-compressed signal is output from the first storage circuit. and a fourth switch that supplies the information read out from the first storage circuit after being band-expanded to the D-A converter via the switch of WJ3 and switches the output of the converter. By taking out the reflected signal through the receiver, a trigger signal that is almost faithful to the original signal received from the reflected signal and a video signal synchronized therewith can be reproduced, and the transmitted azimuth signal can also be read out from the second storage circuit at the same time. A signal recording and reproducing device characterized by: