DE2904933A1 - Ultrasonic transceiver signal echo profile writing circuit - uses intermediate memory and RAM in conjunction with logic circuits to produce echo modulation signal to superimpose on TV screen picture - Google Patents

Abstract

The echo profile writer incorporates a RA, (1) with row and column decoders, respectively connected to dividers (14, 18), the column (n:1) divider being backed up by a another divider (19). The latter and the input memory stage (2) are controlled by the same oscillator (20). A logic circuit incorporating an OR-gate (15) and two AND-gates (16, 17) directs p(n-1) pulses into the appropriate decoders, p being the number of rows and n the number of columns. The input signals enter from a ultrasonic transceiver (3) through flip-flops (4, 5) to the buffer memory (2), prior to entering the RAM (1). The output goes to a modulator (30) which superimposes a signal on the picture synchronisation signals (26-29). The circuit is able to eliminate regular echo patterns (e.g. sea-bottom, ship hull) and write only a recently-received echo (e.g. fish shoal) onto the picture screen.

Description

Echo Profile Recorder for Screen Transmission The invention relates to an echo profile recorder based on the principle of time-of-flight measurement between an output and a reflective sound signal. Echo profile recorders are used to measure the layer thickness of homogeneous materials and to locate foreign bodies in these materials. Known applications of echo profile recorders are for water depth determination and for locating fish heats as well as for measuring material thickness and determining Cavities in the Eirnatz A well-known version of echo profile writing records Recording paper, each echogram lined up on Ma.n receives an echo profile the crossed waterway and can easily recognize the basic conditions and. distinguish these echoes from those of schools of fish. The disadvantage of these devices is the high mechanical effort especially with small measuring ranges with the with it associated susceptibility to failure and the large paper consumption even at relatively slower speeds and thus compact recording, with the registered MeS values already after of interest for a short time.

In laid-open specification 26 15.203, an echo sounder with electronic Memory described which the most recent echograms in a memory and reads this information again so that each echogram next to each other is displayed on the screen of a Braun tube. Npcb of an echo measurement this echogram is displayed on the edge of the screen and the older echograms move one step further to the center of the picture or to the other edge of the picture. That suf the Screen wandering echo profiles therefore always consist of the most recent ones in a row Echograms. The disadvantage of this arrangement is the relatively high price caused by the electronic memory used, the Braun tube with control and of course the components for measuring the transit time of the ultrasound.

To reduce the price of an echo sounder with electronic memory, the proposal was made in the Offenlegungsschrift 27 07 501, the information for the Bra.un'sche tube to be organized and prepared in such a way that it follows modulation of an RF oscillator is fed to a normal television receiver via the antenna socket and can be represented by this. Another price advantage arises at the use of cheaper storage spaces in accordance with the disclosure regulation 27 14 116. With an appropriate echo profile recorder, however, on the television screen the echograms displayed horizontally, so that when used as a ship echo profile recorder the water surface as a vertical line on the edge of the picture and the fashion echoes - with constant water depth - also with a corresponding distance to the water bottle shown as a vertical line. Although all the important ones on the screen Details appear, this representation, compared to the introduced echo profile recorder shows the image rotated by 900, not accepted by skippers.

The invention is based on the object of an echo profile recorder to develop for screen transmission on televisions, which while maintaining the advantages described above represents the echograms perpendicular, so that with a Used as a ship echo profile recorder, the water surface horizontally at the top Edge of the picture is shown.

On the basis of fig. 1 the invention is explained in more detail0 The start-stop oscillator (20) forms a free-running generator with the divider (19) and the mono FF- (25) with the line frequency of the television set used, each after counting of n bits of a line the mono FF (28) and this in turn the mono FF (29), which supplies the line synchronization pulse to the modulator (30) for the RF oscillator, triggers. The impulses from the start-stop oscillator (20) also pass through the AND gate (17) to the divider (18), the binary outputs of which on the SSulenselektor of the RAM (1). In reading mode "R" modulates the output "OUT" corresponds to the counters of the dividers (18) and (14) and the memory content of the RAM (1) via the modulator (30) the HF oscillator. Is the number p of rows smaller than that of the television lines, the divider (21) repeats the reading out of one Row several times so that the television picture is written out in full. At 312/313 TV lines and 64 rows results in a favorable division ratio for the divider (21) from 4: 1 or 5: 1. The AND gate (23), the divider (21), the OR gate (15), the Divider (14), the mono FF (24) and the R-S FF (38) form a generator with the Frame rate of the television set used, which is determined by the R-S FF (38) with the line generator synchronized and clocked by the output of the divider (19) The image synchronizing pulse is activated after each image cycle by triggering the Mono FF (26) or the subsequent mono FF (27) from this to the modulator (30) for the HF oscillator directed. In the operation described in this way, the memory content is stored as a Image shown on the television screen.

A trigger signal is used to start measuring a new echogram on the mono FF (4), dss a pulse of cs. 1 ms duration on the ultrasonic transmitter-receiver (3), which rubs a correspondingly long ultrasonic burst over the barium titanate transducer sends the reflected oscillations into the measuring section and via the same oscillator recaptures, selectively amplified and rectified the input of the receiving memory (2) feeds. Parallel to this measurement, the oscillator is activated via the R-S FF (5) (6) started with an adjustable frequency, which the collecting memory (2) via Das OR gate (13) advances. After counting p pulses by the divider (7) the oscillator (6) is stopped via the R-s FF (5). The echogram is located then in time-quantized form in the collecting memory (2).

The takeover frequency of a new echogram in the RAM (1) is nech down through the echo delay for a measurement and up limited by the desire to display the old echograms for a longer period of time. she will at a given frame rate determined by the division ratio of the divider (8), which leads to an AND condition to the NAND gate (16) after z pulses. The others AND conditions for this gate are the position of the divider (19) on n-1, the Position the divider (14) on p-1 and the last repetition in a row after x Repetitions. If all conditions are met, the output of the NAND gate has (16) O signal and blocks the next pulse from the start-stop oscillator (20) to the Divider (18) by the AND gate (17). This means an asynchronism between the memory locations shown, due to the divider (19) and the read out Storage locations, due to the divider (18), which in this line only increases by n-l steps has switched. As a result of asynchronism, the picture must therefore move around one place hike. After fulfilling the AND condition of the NAND gate (16) and another The image synchronization pulse is emitted via the mono FFs (26) and (27) and the tilting back of the image is initiated. During this time, the pillar of the RAM's (1) on which the divider (18) has stopped and in which the oldest echogram stored wnr, the new echograrnrn read from the catch memory (2) and. so that the old one is deleted The following order of reading can only be selected, if the dividers (14) and (18) have the same dividing ratio, otherwise it would have to the reading in of the new echogram takes place with p pulses during the image reversal. The output of the divider (8) clocks the counter FF (9) and prepares the D FF (10) to set before. If the start-stop oscillator (20) is now started, it is through the clock pulse is also set by the D FF (10) and through the output also the count FF (11th) set. This switches the RAM (1) to write "W" and the AND condition for the AND gate (12) is added. Now p = n counting pulses arrive on the collecting memory (2) and the divider (14), so that i.n the fixed column because the new echogram is adopted. This arrangement shown is used for reading the start Ston oscillator (20) and the divider (19).

The representation of the contour lines takes place according to FIG. 2, by following a certain position of the divider (14) - e.g. the number 8 - the number FF (37) over the Line "b" is set at the beginning of a line and over after the end of the line "c" is reset again. The output Q modulates via the modulator (30) the RF oscillator.

The warning line is shown according to FIG. 2 by bl end of image Triggered the Mono FF (31) with an adjustable reset time via line "a" will. After this mono time has elapsed, the counter FF (32) is set and at..Regin.r of a new line, the downstream D FF (33) is also set via "d". To At the end of the line, the D FF (33) and the number FF (32) are reset. The exit Q of the D FF (33) also modulates the HF oscillator via the modulator (30).

For better differentiation between the warning line and the contour lines it is recommended to additionally modulate the output Q of the D FF (33) so that the Warning line is shown as a dotted line. The triggering of the warnings by the output of the AND gate (36) takes place when the D FF (R4) after writing the first row is reset via "g" until it is set by the Mono FF (31) and if at the same time echo pulses are read out of the RAM (1) via "e" and the number FF (35) by Q = 1 signals the count 1 of the divider (19).

Claims (5)

Claims 1) Echo profile recorder for screen transmission, which is the transit time between an emitted ultrasonic signal and its arrival evaluates a reflection as a measure of the distance traveled by the sound and the Reads echo signals in time-quantized form into an electronic memory, characterized in that when reading out the main memory - RAM (1) - two in parallel switched dividers (18) and (19) controlled by a common oscillator (20) of which the outputs of the divider (18) select the column selector of the RAM (1) and the divider (19), after dividing by n pulses, one line synchronization pulse each time outputs and the divider (14) advances, the outputs of which the row selector of the Select RAM's, whereby after counting through the last row p an image synchronization pulse is issued and then the row selector selects the first row again and itself this process can be repeated as often as required, synchronized with the scrolling of the image, until a new echogram can be read into the RAM (1) from the storage memory (2) should, after encoding pn-1 pulses during a readout operation of the oscillator (20) the divider (18) the last incremental pulse due to the appropriate satter (16) and (17) are no longer received, which results in an asynchronism for this readout process arises between storage and express run, and in the time of the following Scroll back to the column that has now been selected and a new echogram from the storage memory (2) is read in by the RAM (1) for the time of taking over reading Writing is switched and the divider (14) for the row selector and the latch (2) p pulses received, which the synchronous takeover of the memory (2) causes the time-quantized echogram located. 2) Echo profile recorder for screen transmission according to claim 1, characterized in that each row several times according to the division ratio of the divider (21) between the divider (19) and the divider (14) is switched on, reads are carried out consecutively. 3) Echo profile recorder for screen transmission according to claims 1 and 2, characterized in that not after each image cycle, but only after a number of passes corresponding to the divider ratio of the divider (8) whose output causes the asynchronism between memory and image scrolling and initiates the reading in of a new echogram. 4) echo profile recorder for screen transmission according to claims 1, 2 and 3, characterized in that the scaling of the contour lines on the screen is done by lightening an entire line by adding an easily decodable Counter reading from the divider (14) - e.g. counter reading 8, 16, 24 etc. - the FF (37), whose output is fed to the modulator (30), sets at the beginning of a line and a signal from the divider (19) is reset at the end of the line. 5) echo profile recorder for screen transmission according to claims 1, 2, 3 and 4, characterized in that dap. in the picture of the display device one in the Adjustable height limit is faded in by placing a mono FF (31) at the end of the picture or at the beginning of the picture and after the adjustable mono time has elapsed the the following line is lighted by the FFs (32) and (33), whereby for better Differentiation to the contour lines, the output of the FF (33) is additionally modulated and d. the warning is triggered if the AND condition of the gate (36), namely expiry of the mono time of the FF (31), echo pulses from the memory and count 1 of the divider (19) is fulfilled at the same time