JPH0216995B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a device that uses a rotary encoder to rotate an electronic azimuth marker displayed on the display screen of a radar device that employs the PPI method.

Relatively new radar equipment replaces the traditional angularly graduated cursor board with an electronic orientation marker displayed on the display screen to measure the orientation of the signal present on the display screen. The rotation of the orientation marker to a desired orientation is performed using a rotary encoder due to mechanical and cost considerations. That is, the rotary encoder is configured to add or subtract rotational pulses sent out every time the rotary encoder rotates by a certain angle based on the direction of rotation, and display the orientation marker at an angular position corresponding to the counted value. When observing signals in radar equipment, the rotary encoder has a azimuth resolution of 1
It is preferable that each rotation pulse corresponds to about 0.1° on the screen. By the way, rotary encoders, which are currently popular, send out about 50 rotational pulses per rotation, so for example, if you want to rotate the orientation marker half a revolution on the screen, you have to rotate the rotary encoder 36 times. This makes it difficult to set up quickly, and also poses problems in practical terms. Therefore, as a method to achieve both the above-mentioned resolution and quick setting, (1) attaching a gear mechanism for speed increase, or (2) using a high-resolution rotary encoder that sends out about 1000 rotational pulses per rotation, for example. It is possible to use

However, regarding (1), the addition of mechanical parts increases the size of the device, and regarding (2), it increases the cost and, conversely, makes fine adjustment difficult, so it cannot be said to be a fundamental solution.

The present invention has been made in view of the above, and uses a commonly used rotary encoder, reduces resolution only when the rotational speed exceeds a certain level, and increases the rotational movement speed of the orientation marker. The present invention provides an orientation marker rotation device using a rotary encoder that maintains the desired resolution during normal rotation.

The following description will be made based on the embodiments shown in the drawings.

In Fig. 1, 1 sends out, for example, 50 rotation pulses per rotation, and at the same time outputs a high (hereinafter referred to as H) level output when the rotation direction is clockwise, and a low level output (hereinafter referred to as L) when the rotation direction is counterclockwise. ) This is a rotary encoder that can detect the amount and direction of rotation by sending out a level output. Although it is not essentially necessary considering the time lag of each electronic element, it is provided from the viewpoint of ensuring stability of circuit operation, and is a delay circuit that delays the transmitted rotational pulse by a minute time. Reference numeral 3 is a monostable multifunction device that operates using delayed rotational pulses and sends out pulses with a fixed time width, and is equipped with a Q output end that sends out H level pulses and an output end that sends out L level pulses by sending out pulses. . When the next rotation pulse is sent within the above-mentioned fixed time, the monostable multi 3 continues to operate for a fixed time from that point onwards. 4 to 7 are reversible counters, the output count value of reversible counter 4 is the value in the first digit after the decimal point, the output count value of reversible counter 5 is the value in the first digit, and the output count value of reversible counter 6 is 2. The output count value of the reversible counter 7 indicates the third digit value, and thereby an azimuth value of 0.0° to 359.9° can be obtained. Although 0.0° and 359.9° are not shown in the drawings, they are assumed to be continuous in operation. The CI (carry-in) terminal of the reversible counter 4 is normally set at L level so that a counting operation is performed by sending a rotational pulse to the CK (clock) terminal. On the other hand, reversible counters 5, 6, and 7 should, in principle, prohibit counting operations except when carrying up or down.
The CI terminal is normally set at H level. or,
The U/D (up-down) terminal is configured to perform addition counting when an H level is applied, and subtraction counting when an L level is applied. To carry up or down by the reversible counters 4, 5, and 6, send an L level signal from each CO (carry out) terminal, and perform the counting operation of the reversible counters 5, 6, or 7 one digit higher only once. It is done by. The count values of the reversible counters 4 to 7 are sent out, for example, in binary code and guided to the orientation display 8 and the orientation marker generation circuit 9.

Although the azimuth marker generating circuit 9 is not shown in detail in the drawing, this circuit varies depending on the display method of the detection signal of the radar main body (not shown) including the display 10. In other words, (1) record the detection signal in one screen's worth of memory;
In the case of a system in which this is repeatedly read out and displayed in X-Y raster scanning or spiral scanning, the orientation θ is stored in the memory together with the detection signal, or is stored in a separate memory with X and Y coordinates converted, or as it is (spiral (in the case of scanning), it is written at regular intervals. This certain period of time is related to the follow-up ability when changing direction, but it is conceivable to write to a predetermined location for each transmission (within a pause period from the end of writing the received signal to the next transmission), for example. Furthermore, if a dedicated memory for the orientation θ is provided, it may be associated with transmission, or writing may be performed at an independent cycle (for example, the cycle of reading and displaying).

(2) In the case of a display method using radial scanning that rotates sequentially In this case, the orientation θ does not need to be memorized, but can be captured and displayed at regular intervals. This fixed period of time is related to the tracking ability as described above, but may also be made to coincide with the transmission cycle, for example (scanning is performed at least once in the azimuth θ direction during the pause period from the end of displaying the received signal to the next transmission). ,
Also, it may be about one integer fraction of that.

In this way, the azimuth marker generation circuit 9 has a primary relationship with the display method, and although the outline of its operation has been explained in (1) and (2) above, such technology is well known.

In the above circuit configuration, the second
This will be explained with reference to the waveform diagram in the figure.

In Figure 2, A is rotary encoder 1
is a waveform diagram when rotating at a normal speed (below a preset constant speed), and B is a waveform diagram when rotating at a speed higher than the above-mentioned constant speed. Therefore,
Below, cases A and B will be explained separately. still,
For convenience of explanation, the current orientation θ is used in both cases A and B.
150.0°, and the rotation direction of rotary encoder 1 is clockwise.

In case of A, rotate rotary encoder 1 clockwise to generate rotation pulse.
When B ₁ is sent out, this rotational pulse B ₁ is guided to the CK terminals of the reversible counters 4 to 7. The rotation pulse B ₁ is counted by a reversible counter 4, and changes the counted value from 150.0° to 150.1°, for example. Further, the rotation pulse B ₁ is delayed by a minute time t ₀ in the delay circuit 2 (pulse C ₁ ) and then sent to the monostable multi-pulse 3. The monostable multi 3 is activated by the input of the pulse C ₁ and outputs an H level pulse D ₁ from the Q output terminal, leading to the CI terminal of the reversible counter 4 . Therefore,
The reversible counter 4 waits for a predetermined time t after the counting operation is completed by sending the rotational pulse B ₁ (more precisely, after t ₀ )
is considered to be in a non-counting state. Here, the delay circuit 2 outputs a pulse after the counting operation in the reversible counter 4 is completed.
This is to ensure that D ₁ is sent.

Now, the normal H level voltage from the CO terminal of the reversible counter 4 is sent to one input terminal of the AND circuit 11, and the L level pulse E ₁ from the output terminal of the monostable multi 3 is sent to the other input terminal. and sends out L level pulse _F1 . As a result of this L level pulse F ₁ being led to the CI terminal of the reversible counter 5, the reversible counter 5 is enabled to count instead of the reversible counter 4 during period t. Of course, in case A, due to the rotation speed of the rotary encoder 1, the rotation pulse b
As shown in the figure, since the sending cycle of is T (>t), the next rotation pulse B ₂ is not generated during the sending period of the pulses D ₁ and F ₁ , and therefore the rotation pulse B ₂ is also It is counted by a reversible counter 4.
Then, change the count value from 150.1 to 150.2.

In the case of (b), when the rotary encoder 1 is rotated clockwise at a certain speed or higher and a rotation pulse B' ₁ is sent out, the rotation pulse B' ₁ is counted by the reversible counter 4 as described above,
Change the count value from 150.0 to 150.1. After the rotational pulse B' ₁ is delayed (pulse C' ₁ ), it is sent to the monostable multi 3, and by this pulse C' ₁ Q,
H and L level signals are sent from the output end.
Therefore, as described above, only the reversible counter 5 is allowed to count for at least time t. The monostable multi 3 returns to its original level state after operating for a time t, but when the next rotational pulse occurs within a time t, it continues to maintain the same output level for an additional time t. Therefore, the rotation pulse b' has a period t
As long as the rotary encoder 1 is rotated so that Ru. As a result, the count value changes by 1 from 150.1 to 151.1, 152.1, 153.1, . . . due to the generation of rotational pulses B' ₂ , B' ₃ , B' ₄ .

In this way, to change the value by 180 (half a turn), the rotary encoder 1 only needs to rotate 3.6 times, which is 1/10 of the conventional rotation.

As explained above, according to the present invention, the rotary encoder has high resolution when rotating at low speed, such as when making fine adjustments to match the display symbol and the orientation marker, and on the other hand, when rotating the orientation marker relatively largely, the resolution is taken into consideration. It is extremely practical because it rotates at high speed without any rotation.

In this embodiment, the rotation of the rotary encoder 1 causes counting to be performed in units of 1° all at once from 0.1°, so it may feel a little unnatural during use. From this point of view, FIG. 3 shows a case where the unit is changed stepwise according to the rotational speed of the rotary encoder 1.

In Figure 3, rotary encoder 1, monostable multi 3, reversible counters 4 to 7 and AND
Circuit 11 is identical to that of FIG. 12 and 13 are frequency dividing circuits that divide the frequency of the rotation pulse by 1/4 and 1/2, respectively. Functionally, 3 and 14 are monostable multis corresponding to monostable multi 3 shown in FIG.
The monostable multi 3 has an operating time t ₁ (corresponding to t in the previous embodiment), and the monostable multi 14 has an operating time t ₂ (<t ₁ ). 15 and 16 are D-type devices that determine whether the sending speed (period) of the rotation pulse is small, intermediate, or large compared to the times t ₁ and t ₂ and sends out 2 bits of information, 1 bit each. It is a flip-flop (hereinafter referred to as FF). That is, these FFs 15 and 16 determine the sending speed (period) of the rotation pulse by detecting the presence or absence of the rotation pulse within the time of the monostable output. the above
When the rotation pulse is sent to the CK terminal, FF15 and FF16 output high as Q output if the D terminal is at H level.
The level is maintained, and conversely, when the D terminal is at the L level, the L level is sent out. 17 is a rotation pulse based on the sending information of the above-mentioned FFs 15 and 16, an output pulse of the frequency dividing circuit 12, and the frequency dividing circuit 13.
This is a selection gate that allows any of the output pulses to pass through.

The operation will be briefly explained below.

(i) When the sending cycle of the circuit pulse is t ₁ or more (low speed) In this case, the monostable multi 3 keeps the Q output at the H level for t ₁ time by sending the rotation pulse, and the monostable multi 14 keeps the Q output at the high level. t Set to H level for only ₂ hours. However, since the next rotation pulse is sent to the CK terminals of FFs 15 and 16 after time _t1 , both the D terminals of FFs 15 and 16 are returned to the L level at that time. Therefore, the Q outputs of FF15 and FF16 are both at the L level at the time of sending out the rotation pulse, and therefore the selection gate 1
7 is a reversible counter 5, 6, 7 which passes only the rotation pulse directly.
Lead to CK terminal. At this time, the AND circuit 11 is connected to the CO of the reversible counter 4 as in case A of the embodiment.
Since the end is normally at H level and the output of FF 15 is at H level, the reversible counter 5 is in a non-counting state because it is sending out H level as an output. On the other hand, since the CI end of the reversible counter 4 is at the L level, the reversible counter 4 is in a countable state, and thus the rotational pulses directly sent from the rotary encoder 1 are counted. Then, as in case A above, the counted values are 150.1, 150.2...
The orientation is changed by 0.1° per rotation pulse as shown in the figure. Incidentally, in this case, the reason why the rotation pulse is guided to the reversible counters 5, 6, and 7 is to ensure counting operation during carry and carry-down.

(ii) When the sending cycle of rotational pulses is between t ₁ and _{t 2} (medium speed) In this case, the monostable multi 3 outputs an H level as the Q output because the next rotational pulse is sent within the operating time t ₁ . and conversely, monostable multi 14 is Q
The output is at H level for _t2 hours and at L level when the next rotation pulse is sent. Therefore, the Q output of FF15 is always at H level, and conversely, the Q output of FF16 is maintained at L level because the Q output of monostable multi 14 has been returned to L level by the time the rotation pulse is sent. Gate 17 selects the output
is leading to The selection gate 17 passes the output pulse of the frequency dividing circuit 12, which divides the frequency of the rotation pulse by 1/4 based on the above-mentioned H and L levels, and guides it to each CK terminal of the reversible counters 5 to 7.

Furthermore, since the Q output of the FF 15 is at the H level as described above, the reversible counter 4 does not perform a counting operation. At this time, as mentioned above, the AND circuit 11 assumes that the CO terminal of the reversible counter 4 is normally at H level, and the FF15
Since the output is at the L level, the reversible counter 5 is in a countable state because it is sending out L bells as an output. On the other hand, the reversible counter 4
Since the CI terminal is at H level, the reversible counter 4 is in a non-counting state. Therefore, the 1/4 frequency-divided pulses passing through the selection gate 17 are counted by the reversible counter 5. The count value changes by 1° for every four rotational pulses, that is, the orientation changes by 0.25° per rotational pulse.

(iii) When the sending period of rotation pulses is within _t2 (high speed) In this case, the Q outputs of the monostable multi-units 3 and 14 always maintain the H level. For this reason, FF15,
16 Q outputs are both at H level, and the H level signals are guided to selection gate 17. The selection gate 17 passes the output pulse of the frequency dividing circuit 13 which divides the frequency of the rotation pulse by 1/2 based on the H and H levels, and guides it to each CK terminal of the reversible counters 5 to 7. At this time, since the AND circuit 11 is sending out the L level as in the case (ii) above, the reversible counter 5 is in a countable state, and the reversible counter 4
is in a non-counting state. Therefore, the 1/2 frequency-divided pulses passing through the selection gate 17 are counted by the reversible counter 5. The count value changes by 1° for every two rotational pulses, ie, the orientation changes by 0.5° per rotational pulse.

In addition, in cases (ii) and (iii), the selection gate 17
The reason why the pulse that has passed through is guided to the reversible counters 6 and 7 is to carry up and down.

As explained above, in this embodiment, since the angle change per rotation pulse can be switched in three stages, the orientation marker can be changed in rotation relatively in conjunction with the rotational speed of the rotary encoder 1.

Although this embodiment is explained in three stages, it is not limited to this, and in general, n
It can be made into stages (n≧3).

Also, although the embodiment shown in FIG. 1 does not have a flip-flop, the embodiment shown in FIG. 3 does, but this is not a fundamental difference; the flip-flop shown in FIG. The same way of thinking is also guaranteed. On the contrary, the first
A flip-flop may also be provided in the diagram.

[Brief explanation of drawings]

FIG. 1 is a circuit diagram showing an embodiment of the present invention, and FIG. 2 is a waveform diagram thereof. FIG. 3 is a circuit diagram showing another embodiment.

Claims (1)

[Claims] 1. In a radar device, based on the fact that a rotary encoder that sends out a rotational pulse every time it rotates at a fixed angle, and a reversible azimuth counter that counts the value of the smallest digit among the rotary encoders, count the rotational pulses. a plurality of azimuth reversible counters for each digit in which the value of each digit is sequentially determined; a signal generating means for transmitting a signal for a predetermined time t from the time of transmitting the rotational pulse each time the rotational pulse is transmitted; Counting control means for counting rotation pulses based on the output of the signal generating means only by a reversible azimuth counter that counts the value of the next digit after the minimum digit when the sending period is 0 to t; An azimuth marker turning device for a radar device, comprising: an azimuth indicator that numerically displays the value of each digit indicated by a reversible counter; and azimuth marker display means that displays an azimuth marker in the azimuth direction on a radar signal display. 2. In a radar device, a rotary encoder that sends out a rotational pulse every fixed angle rotation, and a reversible azimuth counter that counts the value of the smallest digit among these, calculate the value of each digit in sequence based on the rotational pulses counted. a plurality of reversible azimuth counters for each predetermined digit, and a first unit that transmits signals at predetermined times t ₁ and t ₂ (t ₁ >t ₂ ) from the transmission time each time the rotation pulse is transmitted. a second signal generating means, the rotation pulse is 1/m ₁ , 1/m ₂ (m ₁ <m ₂ );
The sending period of the rotating pulse is determined by detecting the presence or absence of the rotating pulse within the signal sending time of each of the first and second frequency dividing circuits and the first and second signal generating means. a gate means for passing a predetermined one of the divided outputs of the first and second frequency dividing circuits based on the determined output of the determining means; and a gate means for transmitting the rotational pulse. When the period is between _t1 and _t2 , the divided output passing through the gate means based on the output of the first signal generating means is counted only by a reversible azimuth counter that counts the value of the next digit after the minimum digit. It comprises a counting control means, an azimuth indicator that numerically displays the value of each digit indicated by the plurality of reversible azimuth counters, and an azimuth marker display means that displays an azimuth marker in the azimuth direction on the radar signal display. An orientation marker rotation device in a radar device.