JPS5928381Y2 - Rotating detection radar - Google Patents

Description

[Detailed explanation of the invention] This invention rotates the pointing direction of a directional antenna and displays the reflected waves received by the antenna on a PPI display.
This relates to a turning detection radar that is displayed.

For example, a magnetron is used for the radar transmitting tube,
The magnetron has been turned on for a relatively long time,
For example, a preheating time of about 3 minutes is required.

For this reason, conventionally, when the radar power is turned on, an indicator light lights up after the predetermined preheating time required for the transmitting tube has elapsed, indicating that it is now possible to start transmitting. It was supposed to be.

However, when you have to wait a relatively long time after turning on the power before starting the radar, you are usually doing other work during that time, and you are concerned about whether it is ready to transmit. While working, they often check to see if the indicator light is on, but because they do not know how much time is left until the radar becomes operational, they are unable to do their work calmly.

Generally, when the power is turned on, the radar reads the time on the clock, and then checks the clock from time to time to know how much time is left until the radar is ready for operation.

Even so, it was necessary to check whether the radar indicator light was actually lit while looking at the clock, which was inconvenient to see the difference between the clock and the radar indicator light.

By displaying the elapsed time since the power was turned on as an angle on the radar display, this device allows you to easily read the remaining time until the radar is ready for operation, and you can also see the indicator light at the same time. The object of the present invention is to provide a rotating detection radar with a similar shape.

The radar according to this invention will be explained below with reference to the drawings.

In this embodiment, the detection signal (reflected signal) is displayed on a color display in different colors depending on its reflection intensity, and the display surface of the display is spirally scanned in order to display PPI. This is the case.

(1) The overall configuration has the functional block configuration shown in Figure 1,
A functional element, ie, a device or a circuit, performs the following operations:

The antenna section 1 receives transmission control from the storage/control section 2, transmits/receives waves to obtain a detection signal while rotating the pointing direction of the antenna 101, and sends the received detection signal C1 of the detection signal to the storage/control section 2. give.

The storage/control unit 2 processes and stores the received detection signal C1 given by the antenna unit 1 according to the display purpose, provides the signal-processed output to the display unit 4, and also outputs the marker to the marker generation unit 3. Give a reference signal.

The marker generating section 3 provides the display section 4 with a marker signal according to the purpose of display.

The display section 4 displays the signals given from the storage/control section 2 and the marker generation section 3 as color images on a color display screen according to the display purpose.

(2) The antenna section 1 has the functional block configuration shown in Fig. 2,
A functional element, ie, a device or a circuit, performs the following operations:

The antenna 101 has a narrow beam-like wave transmitting/receiving directivity and is continuously rotated by a motor 103.

The main signal waveform of the antenna section 1 is as shown in FIG. 2A.

When the transmitting/receiving unit 102 receives the transmission trigger signal b1, it generates a pulse signal, emits a pulse radio wave using a microwave as a carrier wave from the antenna 101, and receives a reflected signal from the target, that is, a detection signal. , obtain a received detection signal C1.

The transmission pulse width is controlled by the range signal a1, and when the range is short, the short width f1. When the range is long, the length is 11.

Moreover, the reception sensitivity j1 is 5 in synchronization with the transmission trigger signal b1.
TC (sensitivity time control) is performed.

The rotation angle detection unit 105 uses a photointerrupter, a Hall element, or a reed switch, and generates a pulse signal of the rotation angle signal e1 every time the antenna 101 rotates by a certain angle.

For example, as shown in Figure 2A, one pulse every 0.5°,
Outputs 720 pulses per revolution.

The bow direction detection unit 104 emits a pulse signal of the bow direction signal d1 when the pointing direction of the antenna 101, that is, the radio wave transmission/reception direction is in the bow direction.

For example, one pulse is output for one rotation.

(3) The storage/control unit 2 has the functional block configuration shown in FIG. 3, and the functional elements, that is, devices or circuits operate as follows.

■ Overall operation The received detection signal C1 is AD converted into an n-bit digital code by the AD converter 201 to produce a digitized received signal m2 (referred to as D signal), and when the rotation angle signal e1 arrives as shown in Fig. 3A, The first transmission trigger signal b
Within a period of 41 from 11 to the next transmission trigger signal b12, the detection distance range bones, that is, data D1 to DM for the range are sequentially stored in the M-bit memory (1) 202 as shown in FIG. 3B. Write.

Starting from the next transmission trigger signal b12, the memory (
1) Read out the contents of 202 in the same order as they were written, and use this read signal and the D signal m2 obtained from the received detection signal C1 at that time as an ant game for correlation.
The first D signal m2 and the second D signal m2 are compared, and the time after the radio wave is emitted is at the same position, that is,
Only the signals generated when there is a reflected signal both at the same distance point for the first and second time are written into the M-bit memory (2) 204 to eliminate the influence of noise.

After the above operation is completed, within period t23 before the next rotation angle signal e1 arrives, the data in memory (2) 204 is transferred to N memories (
3) 205. Figure 3C i 2 in memory (4) 220
As shown in 3, it is transferred by N bits.

In this example, the angular resolution is 0.5°, 360° is 7
It is displayed as 20 display lines in the radial direction, and as the distance from the center of each display line (indicating the position of the antenna 101) increases, the detection signal is DI, D2, etc. The subscript i of DM and Di increases. The memory (3) 205 is A1 to AN (N = 1 in this example).
2), the detection signal 1 (111(111(1) DI, D2...DM) for the 0.5° direction is stored in the memory A1 every 60 bits, and 1. Detection signals 1 (2) 1 (21 DI, D2...DM) in the 0° direction are sequentially stored in memory A2 every 60 bits, and the detection signals 1 (2) in the 6.0° direction are stored in the same manner. ) l ■ 1 (g) DI, D
2...DM is sequentially stored in the memory AN every 60 bits, and the detection signal 2 (1) 2(1) 21) Di D2...DM is stored in the memory in the 6.5° direction. The previously stored 0 and 5 are stored in A1 every 60 bits.
Stored sequentially at addresses adjacent to the signals in the ° direction.

If you memorize the following in the same way, in this example N=12 and the resolution is 0.5°, so 720゛÷12 =
The detection signal in the 5° direction of 355° from 60 is 60 (G) 60 (G) 6° (G) DI, D
2...DM is displayed and stored in the memory AN as shown in FIG. 3C.

In this way, all addresses in memory (3) 205 are filled.

The contents of memory (3) 205 and memory (4) 220 are read out and output in synchronization with sweep signal (1) d2 and sweep signal (2) f2.

FIG. 3A shows the time relationship between the main operations of the memory, FIG. 3C shows the layout of the memory (3) 205, and FIG. 3D shows the relationship between the spiral sweep and the memory layout.

(2) Operation of each function The AD converter 201 converts the analog amplitude value (for example, voltage value) of the received detection signal C1 into an X-bit digital value.

In this AD conversion, the peak value is sampled and held, and the hold is reset every time the address of the memory (1) 202, which will be described later, changes.

The selector (1) 207 receives the clock ckl and the range signal a1, and calculates the pulse period of the value obtained by dividing the time for the radio wave to travel back and forth over the full scale of the range (detection distance range) by the number of bits M in the memory (1) 202. selector with (1
) outputs an output signal g2.

The counter (1) 20B counts the pulses of the output l signal g2 of the selector (1) 207 and outputs the transmission trigger signal b1.
is set (reset) to 0 by the signal h2 delayed by the delay circuit 215.

The output signal of counter (1) 208 is sent to memory (1) 2.
02, which is the write address of memory (2) 204.

Counter (2) 216 counts clock Ck2,
It is set to O by the output of the read/write control unit 218.

This signal is memory (1) 202, memory (2) 2
These are the read address of 04 and the write address of memory (3) 205 and memory (4) 220.

The operations of memory (3) 205 and memory (4) 220 are as follows.

[Write to memory (3) 205 and memory (4) 220] Bits D1 to DM of memory (2) 204 are written to every N bits of memory (3) 205 and memory (4) 220.

The insertion positions are counter (3) 222 and counter (2).
)216 address.

[Reading of memory (3) 205 and memory (4) 220] The contents of 1 to N are read out simultaneously.

The memory (1) 202 has a read/write control unit 218
With the output of , the AD conversion output of the AD converter 201 is written/read using the output of the counter (1) 208 as an address.

One sweep in the distance direction (
1 firing cycle) minutes.

Memory (2) 204 stores the AND output of the output of memory (1) 202 and the AD conversion output of converter 201, the output of counter (1) 208 as an address, and also stores the output of counter (2) 216 as an address. Read as an address.

This writing/reading control is performed by the read/write control unit 218.
This is done by the output of

The selector (3) 209 is the read/write control unit 21
With the output of 8, the output of counter (1) 208 and counter (2) 216 is switched and selected, and memory (1)
202, output as the address of memory (2) 204.

Counter (3) 222 counts the rotation angle signal e1.

O is set (reset) using the bow direction signal d1. This output becomes an address indicating the rotation direction when writing to memory (3) 205 and memory (4) 220.

Counter (4) 227 generates read addresses for memory (3) 205 and memory (4) 220, and as shown in FIG. 3F, counter 2271 determines the address in the rotation direction and counter 2271 determines the address range in the distance direction. 2272.

Alarm range mark b2 is alarm setting 217 (manual switch)
This is the signal output when the counter 227 is turned on.
2 is in the approach alarm address predetermined according to the range set in the range setting section 213 at that time, two ring lines G and H (third
This is a signal for displaying (Figure G).

The operational relationship between the counter (2) 216, the counter (3) 222, and the spiral sweep is shown in Figure 3E.
4) The block configuration of 227 is shown in Figure 3F, the display image of the alarm range mark is shown in Figure 3G, and the signal relationship of alarm operation is shown in Figure 3H.
As shown in the figure.

The 17N frequency divider 226 divides the clock ck3.

Clock ck3 is synchronized with clock ck2.

Counter (4) 227 counts the output of 1/N frequency division 226.

This output is memory (3) 205, memory (4) 22
It becomes a read address of 0.

The selector (4) 223 is the read/write control 21
8, the outputs of counter (3) 222, counter (2) 216, and counter (4) 227 are selected and output.

The selected output is Memory (3) 205, Memory (4)
)220 address.

Memory (3) 205 writes the output of memory (2) 204 using the output of counter (2) 216 given via selector (4) 223 as an address, and writes the output of memory (2) 204 via selector (3) 209 to the given counter (
4) The output of 227 is read out as an address, and N pieces are arranged in parallel as a unit.

Shift register (1) 206 is memory (3) 20
Every time the read address of 5 changes, the memory (3) 205
Input N bits of data in parallel and clock ck
Outputs serially with 3 clocks.

Therefore, in FIG. 3C, first DI, DI, DI...Dl are read out in parallel from memory (3) 205, set in shift register (1) 206, this is output as serial data, and then ) 205 to 2(1) 2(2+ 2 (g) DI
, DI...Dl are read out in parallel and converted into serial data by the shift register (1) 206, and the same process is performed thereafter.
When reading memory (3) 205 for the 60th time, DI, DI
...Dl is obtained.

In this way, the one closest to the antenna in the detection signal is 3
This means that the samples were taken out sequentially over 60°.

1 (1) by next reading of memory (3) 205
1 (2) 1(N)D2. D2
...... D2 is read out in parallel and converted into a serial signal by the shift register (1) 206, and in the same way, the signal closest to the antenna in the detection signal, which is one distance resolution away from the antenna, is
obtained sequentially over °.

The same applies hereafter.

Therefore, in synchronization with the reading of this memory (3) 205 and the shifting operation of the shift register (1) 206, the CRT 41
6 is spirally swept, the detection signal is displayed in PPI.

Memory (3) 205 and shift register (1) 20
6 is combined with memory (3) 205 because the reading speed of memory (3) 205 is relatively slow. If this reading speed is fast enough, memo IJ-(3) 205 can be sequentially read and shifted so that the above serial signal is obtained. Register (1) 206
may be omitted.

Memory (4) 220 operates at the same address as memory (3) 205, and plotter setting section 224
When turned on, the output r2 of the memory (2) 204 and the previous data stored in the memory (4) 220 are OR gated in (D) 219, and the output is written as input.

Shift register (2) 221 is memory (4) 220
Obtain the 1-bit output of shift register (1) 2
It operates in the same way as 06.

The retrace time generation unit 228 generates the retrace time after sweeping displaying one display screen.

Since the counter (4) 227 counts one display screen, the retrace time generating section 228 operates based on this output.

The display unit 212 displays the value of the detection display distance range on the display screen selected and set by the range setting unit 213.

The range setting section 213 generates a range signal al for performing a detection display operation corresponding to the detection range selected and set by a manual switch, a control signal for the period generation section 214, and a counter (1).
) 208 count speed control signal, display section 304 (fourth
2 is output as the unit distance signal for calculating the VRM distance value displayed in the figure).

The range signal a1 is a code signal for operating a relay for switching a pulse width constant circuit provided in the transmitting/receiving section 102 shown in FIG.

The period generator 214 generates a transmission trigger signal b1 having a transmission period (detection period) obtained by controlling the counting of the clock ck2 based on the output of the range setting section 213.

The purpose of the delay circuit 215 is to correct the operation delay time of the transmitter/receiver 102, and delays the reset signal of the counter (1) 208 so that the memory (1)
) 202, the received detection signal C1 is stored in the memory (2) 204.
The timing of reading the D signal m2 obtained by AD converting the data is made to match.

The read/write control unit 218 controls the timing of transferring the contents of the memory (2) 204 to the memory (3) 205 and the memory (4) 220, and performs address and write/read switching operations for this purpose.

The relationship between plotter operation signals and alarm operations is shown in Figures 3H and 3-3.

The figure shows a hypothetical case in which the digital values of each signal are converted into analog values, and the operating levels are switchable semi-fixed values, for example, set to the signal strength of the red level of the display.

The plotter setting unit 224 outputs a time-controlled plot timing signal when the plotter operation is ON, and gates (
D) 219 and input to memory (4) 220.

Further, the plotter setting section 224 outputs a plotter signal C2 for changing the display color through the game (C) 225.

Game) (D) 219 controls the plotter manually.

The previous content W2 of memory (4) 220 and the current output of memory (2) 204 (data r2 above the preset operating level) are OR gated and the write input of memory (4) 220 is performed. Output S2.

Furthermore, this gate (D) 219 is connected to the plotter setting section 2
It is controlled as an AND gate by the output of 24, and 0N-
OFF works.

The plotter signal C2 is a signal for displaying the track of a specific past detection signal image (target image) by making it neutral (dark).

When the alarm setting section 217 is turned on, the gate (A) 210 and the gate (B) 211 operate at a specified operation level (number 1) within a preset distance range (this range is determined from the contents of the counter (4) 227). When the above signal (Figure 3H) is obtained from the shift register (1) 206, the signal is inverted at the gate (A) 210, for example, every 0.5 seconds and outputs a signal x2.

(B) 211 ANDs the output signal of the gate (A) 210 and the output signal of the shift register (1) 206.
gate and output display data a2.

As a result, signals above the operating level within the setting range are
The image will flash on the display screen.

If the alarm setting section 217 is not turned on, the output signal p2 of the shift register (1) 206 is GA) (B) 2
Pass through 11 as is.

Display data a2 is CR of the contents of memory (3) 205.
This is a signal read out in synchronization with the T-display spiral sweep, and is, for example, a parallel 2-bit digital signal.

The clock generator 229 generates clocks ckl and ck2 for creating timings for writing and reading memory (1) 202 and memory (2) 204, and a CRT display screen (FIG. 5).
A clock ck3 is generated for creating the timing of the signal for the spiral sweep display.

(4) The marker generating section 4 shown in FIG. 1 has the functional block configuration shown in FIG. 4, and the functional elements, that is, devices or circuits perform the following operations.

The FRM generation unit 301 generates an FRM (fixed distance mark) signal for displaying a ring-shaped line image C (FIG. 4A a) that divides the display screen at equal intervals in the distance direction.

That is, when the sweep signal (2) f 2 and the sweep signal (1) d 2 reach values indicating the angle and distance corresponding to this FRM, the FRM signal is generated.

The VRM generator 302 combines the contents (values) of an up/down counter (1) 303 to which a pulse signal from a pulse generator 305 (manual rotary pulse generating means) is applied via a switch 313 and a sweep signal (1) d2 (second pulse generator). The counter in figure 3 (
4) Output of 227] and when they match, a VRM (variable distance mark) signal for displaying a ring-shaped line image 2 (FIG. 4A b) on the display screen is generated.

By adjusting the contents of the up/down counter (1) 303, the display position of the VRM changes.

The FBM generator 310 obtains the sweep signal (2) f2 and displays a large number of angle marks (angular scale line images) (FIG. 4A, C) on the outer circumference of the display screen. When the sweep signal (2) reaches a value indicating f2, an FBM (fixed angle mark) signal is generated.

The VBM generator 307 compares the pulse signal from the pulse generator 305 to the up/down counter (2) 308 via the switch 313 and the sweep signal (2) f2 [output of the counter (4) 227]. , at the coincident point, generates a VBM (variable angle mark) signal for displaying a radial line image (FIG. 4A, d) on the display screen.

The display position (direction) of VBM is counter (2) 308
It can be changed by changing the content (value) of .

In addition, this VBM generation unit 307 displays only FBM (fixed angle mark) and VBM during the preheating time of the magnetron (approximately 3 minutes) when the power is turned on, and during this time, the VBM By displaying the (variable angle mark) in the shape of rotating clock hands, it is also used as an analog clock to display the standby time (StandBy) until the start of transmission.

The pulse generator 305 is a rotating pulse generator,
When rotated manually, it generates a number of pulses corresponding to the amount of rotation and also generates a rotation direction signal.

This pulse is passed through the switch 313 to either the up/down counter (1) 303 or the up/down counter (
2) Give to 308.

The gate 306 selectively gates either the output of the pulse generator 305 or the clock ck3 and outputs the gate.

This selection operation is performed by a signal provided by the timer 11.

The display unit 304 displays the distance value of the vRM display position, and displays the contents of the up-down counter (1) 303 and the value obtained by multiplying the unit distance signal by 2.

The display section 309 displays the direction value of the vBM display direction, and displays the contents of the up/down counter (2) 308.

The timer 311 is a timer that measures a certain period of time from when the operating power of the device is turned on, and is used to measure the preheating time of the magnetron mentioned in the explanation of the BM generator 307. During this preheating time, the clock ck3 is In addition, during other periods, the output of the pulse generator 305 is
) 308, outputs a signal to control gate 306, and outputs a signal from gate 312 to FBM.
It outputs a control signal for gating just the signal and VBM signal.

The gate 312 receives display data a2, FRM, VRM, V
This is a gate for outputting a display digital signal a3 (for example, 5 bits in parallel) which is provided to the display unit 4 by organizing the signals of BM, FBM, SHF, blinking by the alarm mark b2, and VBM rotation by the timer.

The moving mark selection (switch) 313 is VRM or V
This is a switch for selecting and setting BM.

The SHF generator 314 generates a bow direction signal d1 and a sweep signal (2
) (circumferential direction) with AND gate, Fig. 4A d
Generates a signal to display the bow indicator line as shown in .

(5) The display unit 4 has the functional block configuration shown in FIG. 5, and the functional elements, that is, devices or circuits, operate as follows.

The main signal waveforms of the display section 4 are shown in FIG. 5A.

Sweep signal (1) (distance direction) d2 is the PPI of the detection signal
This is a signal that determines the sweep speed in the distance direction, that is, the spiral pitch amount in the radial direction for displaying the screen display as a spiral-swept image, and is, for example, a parallel 8-bit digital signal from the counter 2272 in FIG. 3F.

The DA conversion unit 401 performs DA conversion on the sweep signal (1) d2, and converts the sweep signal (1) d2 into 91 cycles per screen sweep (for example, a cycle corresponding to 60 stops).
A distance sweep signal a5 having a sawtooth waveform is output.

Sweep signal (2) (circumferential direction) f2 is sweep signal (1) d
It is a signal that contributes to the sweep in the circumferential direction, that is, the rotational direction, in conjunction with the sweep by counter 22 in FIG. 3F.
71, and is a rectangular wave signal whose period is one revolution of the spiral sweep, for example, a rectangular wave having the same period as a horizontal scanning signal of a television (a period corresponding to about 16 kHz).

The filter 411 is a filter for extracting only the fundamental sine wave component of the sweep signal (2) f2, for example, a low-pass filter of approximately 16 mm, and is a filter for extracting only the fundamental sine wave component of the sweep signal (2) f2.
Output.

Analog multiplication 402 multiplies distance sweep signal a5 and circumferential sweep signal b5, and outputs a sinusoidal composite sweep signal C5 with sawtooth amplitude modulation.

The phase shifter 403 delays the phase of the composite sweep signal C5 to provide a synchronization starting point for the screen display and the display signal of each color given to the CRT 416 based on the display digital signal a3 (the starting point of the circumferential sweep, that is, the starting point of the azimuth angle). A Y-axis deflection signal d5 that matches the Y-axis deflection signal d5 is output.

The amplifier 405 sends the Y-axis deflection signal d5 to the CRT 416.
The output is amplified to the extent that deflection scanning can be performed in a desired amount.

A transformer 406 connects the output of the amplifier 405 to the Y yoke 40.
7, and uses a step-up transformer so that even if the voltage of the circuit power supply of the amplifier 405 is low, a sufficiently high voltage applied to the yoke can be obtained.

The Y yoke 407 is a Y-axis deflection yoke of the CRT 416.

The 90° phase shifter 404 shifts the phase of the Y-axis deflection signal d5 by 90° to generate a cosine-wave X-axis deflection signal e having sawtooth amplitude modulation.
Outputs 5.

The amplifier 408, transformer 409, and X yoke 410
The axis deflection signal e5 is applied to the X-axis deflection of the CRT 416,
It operates similarly to the amplifier 405, transformer 406, and Y yoke 407.

The high voltage generator 412 generates CR from the sweep signal (2) f2.
A high voltage generation circuit that generates high voltage for T416, such as a flyback transformer circuit, and sweep signal (2)
It is generated in synchronization with f2 to prevent an asynchronous striped pattern of brightness due to ripples.

The color encoder 413 is, for example, a color matrix, and outputs each color GBR (green, blue, red) signal in which the digital value of the display digital signal a3 corresponds to the desired color classification.

Plotter signal C2 indicates the previous exploration (antenna 101).
Only when the detected image displayed on the display screen with a signal strength above a certain level moves during the rotation of When the image is, for example, a ship, this signal is used to display its wake, and when this signal C2 is given to the color encoder 413, for example, the display digital signal a3 By performing a negative operation on all human power, the outputs of each color G, B, and R are all rendered non-output.

The retrace signal e2 is a signal corresponding to the so-called unblanking signal of the CRT 416, and has the same period as the sweep signal (1) d2, and has the same period as the blanking period of the spiral sweep on the display screen and the spiral sweep display period width. This is a rectangular wave signal that connects two parts.

The sawtooth wave generator 415 converts the display period width portion of the retrace signal e2 into a sawtooth wave averaged luminance signal f5 that rises in an approximate logarithmic curve shape from its starting point.

This luminance averaged signal f5 is applied to the color encoder 413, and for example, the diode bias value of the color matrix is changed, and each color G according to the display digital signal a3 is
, B, and R in proportion to the amplitude of this signal f5, the display screen of the CRT 416 can prevent uneven brightness such as high brightness in the center due to spiral sweep, Equalizes display brightness across the screen.

The amplifier 414 is a group of amplifiers that amplifies the signals of each color G, B, and R to an output that provides a target luminance, and supplies the amplified signal to the luminance modulation electrode of each color of the CRT 416.

The CRT 416 is a color cathode ray tube, and uses, for example, a color cathode ray tube with a rectangular screen for television, rotated 90 degrees from the front and oriented vertically.

Thus sweep signal (2) f2 and sweep signal (1)
d2 to deflection signal d5. e5 is generated, the CRT 416 is spirally swept, and the sweep signal f2. Since the memory (3) 205 is being read in synchronization with d2, the CRT 41
PPI display can be obtained on the display screen of 6.

(6) The display/operation section of the specific device in the embodiment of this invention has a configuration as shown in FIG. 6, and each section performs the following functional operations.

As mentioned above, in this invention, when the power switch is turned on, a timer corresponding to the preheating time of the transmitting tube is operated, and the elapsed time of the timer is displayed angularly on the display screen of the CRT.

This has been explained by providing a timer 311 etc. in FIG. 4, and a detailed example thereof will be further explained with reference to FIG. 6.

The timer 311 is a switch 60 that works with the power switch.
1 is turned on by the power switch, its output becomes high level after a time determined by the preheating time of the radar transmitting tube, for example, 3 minutes has elapsed.

Therefore, if the radar is in operation, the timer 31 is always on.
The output of 1 is at a high level, AND gate 602 in gate 306 is open, and inhibit gate 603 is closed.

When the moving mark selection switch 313 is switched to the gate 306 side, the pulse from the pulse generator 305 and the signal indicating the rotation direction are further ORed through the gate 602.
The signal is input to an up/down counter 308 through a gate 604 and is counted up or down.

The count content of the counter 308 indicates the set angle of the variable angle mark.

The contents of each count of this counter 308 and the rotational direction address counter 2271 are compared in a coincidence detection circuit 605, and when the two coincide, the coincidence output is sent to a code generator 606.
A digital VBM signal is generated from the gate 312 and supplied to the gate 312.

The count contents of the counter 308 may be displayed as the number of angles on the display section 309, but in FIG. 6, the number of angles is displayed as follows.

The input clock of the rotation direction address counter 2271 (this is generated every 0.5° rotation of the electron beam in the CRT) is input to the counter 608 through the changeover switch 607.
supplied to

The switch 607 selects the output clock of the 1/N frequency divider 226 when the output of the timer 311 is at a high level, and selects the output clock of the 1/N frequency divider 226 when the output of the timer 311 is at a low level.
09 is selected and supplied to the counter 608.

On the other hand, each time the rotational direction address counter 2271 becomes zero, the flip-flop 611 is set, and the flip-flop 611 is reset by a coincidence output from the coincidence detection circuit 605.

The 0 output of the flip-flop 611 is applied to the reset terminal R of the counter 608.

Therefore, after the address counter 2271 becomes zero until a match is detected by the match detection circuit 605, the counter 608 is reset and counts the input clock.

The count value is latched on the display section 309 at the rising edge of the coincidence output of the coincidence detection circuit 605.

The display in section 309 is a variable angle mark (VBM).
The set value of is shown with an accuracy of 0.5°.

However, 0.5° is represented by displaying a decimal point 612.

In this embodiment, the configuration for generating and displaying the VBM signal is used to display the waiting time state from power-on to the start of transmission.

When the power is turned on, the output of the timer 311 is at a low level and the inhibit gate 603 is opened.

Therefore, when the power is turned on and the clock ck3 is generated, this is divided by the frequency dividing circuit 600 into a clock having a period of 0.25 seconds, and is counted up by the up/down counter (2) 308 through the gates 603 and 604.

Since the period of this clock is 0.25 seconds, if we count 720 clocks, 3 minutes have elapsed, and in this example, the display resolution is 0.5°, so
The maximum count value of the rotation direction address counter 2271 is 7.
It is 20.

Similar to the VBM mark, the counting status of the counter 308 is displayed on the CRT display screen as shown in FIG. 7, and in this example, the display screen rotates once every 3 minutes from power-on to the end of the transmission waiting time.

By looking at the angle display on the CRT display screen, you can intuitively understand the elapsed time since the power was turned on and the time until transmission operation is possible.

Furthermore, since this is aligned with the position of the indicator light that lights up when transmission operation is enabled, both can be seen at the same time.

In this example, the output of the timer 311 causes the code generator 60 to
By switching the generation code of 6, the vBM mark and the transmission waiting time display are displayed in different colors to avoid the possibility of confusion between them.

Furthermore, although the maximum value of the VBM angle is displayed on the display unit 309 as 360°, the elapsed transmission waiting time is displayed at a maximum of 180 seconds (3 minutes) in this example, so the output of the frequency divider 226 is The frequency divided by half is the switch 60.
7 to the counter 608.

Therefore, the elapsed time since the power was turned on is displayed on the display section 309.

In this way, in this invention, the elapsed time from power-on to the transmission standby state is displayed angularly on the CRT display screen, and by looking at it, the time until transmission is possible can be immediately determined.

Further, when using the configuration for generating the VBM mark signal as in this example, it is possible to display the elapsed transmission waiting time by adding only a few parts.

This invention can be applied not only to the case where a CRT display is swept spirally to display PPI, but also to the case where it is swept radially to display PPI.

Furthermore, it can be applied not only to color display but also to black and white display.

[Brief explanation of drawings]

Fig. 1 is a schematic diagram of the overall block configuration of the radar of this invention, Fig. 2 is a schematic block diagram of the antenna section 1, Fig. 2A is a side view of main signal waveforms of the antenna section 1, and Fig. 3 is a storage/control section. Figure 3A is a diagram of the operation time relationship of the main parts of the memory, Figure 3B is a layout diagram of the memory (2) 204, Figure 3C is a layout diagram of the memory (3) 205, and Figure 3D is a spiral diagram. Relationship diagram between sweep and memory layout, Figure 3E shows spiral sweep and counter (2)
・Relationship diagram of counter (3), Figure 3F shows the counter (
4), Figure 3G is a display video diagram of the alarm range, Figure 3H is a signal relationship diagram for alarm operation, Figure 3 (2) is a signal relationship diagram for plotter operation, and Figure 4 is a diagram of the marker generating section 3. A schematic block diagram of the block configuration; FIG. 4A is a relationship between the spiral sweep and the display of each mark; FIG. 5 is a schematic diagram of the block configuration of the display section 4; FIG. FIG. 7 is a block diagram of the generation of the VBM signal and the generation of the elapsed transmission waiting time signal, which are the main parts of the invention. FIG. 7 is a diagram showing the elapsed transmission waiting time.

Claims (1)

[Scope of utility model registration request] A rotating detection radar that transmits pulse radio waves while rotating the pointing direction of the directional antenna, receives the reflected waves, and displays the PPI on the display.It operates when the power is turned on and preheats the radar transmitting tube. a timer with a predetermined timer of one hour according to the time; a means for generating a signal indicating the passage of time by operating according to the output of the timer; and displaying the angle of the signal indicating the passage of time on the above-mentioned display. A turning detection type radar characterized by being provided with means.