JPS5812556B2 - Digital direction measuring device display device - Google Patents

Description

[Detailed Description of the Invention] In order to read the azimuth angle at which radio waves arrive as a digital quantity (
On the other hand, in a digital direction measuring device, if the intensity of the incoming radio wave is weak f(1), the displayed digital quantity, especially the F-digit value, fluctuates frequently due to the noise component, making it difficult to read it.

The present invention automatically displays the most frequent value in such a case, making it easier to read it.

FIG. 1 is a block diagram of an embodiment of the present invention, in which the arrival azimuth of radio waves is measured every moment, and the azimuth is indicated by, for example, 10
A three-digit digital signal is applied to terminal P.

Decoder B detects the least significant digit of this digital signal and outputs 10 output terminals 0, 1, 2, . . . , 9 according to its value.
For example, one pi level signal of a binary signal consisting of pi level and low level is sent out from the corresponding terminal among terminals 1, 2, . . . 9.

Therefore, if the input digital signal is also L123, the output terminal 3 becomes the pi level and all other terminals maintain the low level.

The signal of each output terminal and the clock pulse generator K
The output pulses are applied to AND gates Ao, A1 .
Count each separately at 9.

The carry signal of each counter is added to OR gate 0, and all counters C0, C1, . . . , C9 are simultaneously reset by the output signal.

That is, when one of the counters sends out a carry signal, all the counters are reset and start counting the output pulses of each AND gate again.

The output signal of the OR gate O drives the memory M to store the digital signal at the terminal P at that time, and the display D constantly displays the signal stored in the memory.

FIG. 2 is a time chart illustrating the operation of the above-mentioned apparatus, in which a 3-digit decimal digital signal such as p that changes from time to time is applied to the terminal P shown in FIG.

For example, signal 112 indicates that the arrival direction of the radio wave is 112 degrees, and when this signal is added, the output terminal 2 of Tecoder B becomes high level.

Also, K is the output pulse of the clock Hals generator K, and among the anode gates A0, A1..., only the one to which the pi level signal is applied from the output terminal of the decoder B passes this clock pulse to the counter C.

? Add to one of C,... That is, for example, when the digital signal 112 is applied to the terminal P, the cross pulse that is generated is applied to the counter C2 and increases its count value by one, and therefore the counters C0, C1...C9
The count value increases as shown by C0, C1...C, in Fig. 2, and when the count value of the counter C1 becomes 10 at pulse k1 and the carry signal r is sent, all the counters mentioned above increase. will be reset.

Then, the memory M is driven by the carry signal, and the input digital signal at that time, for example, 111, is written into the memory, and the display remains on until the next carry signal r is sent to that signal and the memory signal is rewritten. Displayed by D.

Therefore, after one carry signal is sent and each counter is reset at the same time, the digital signal corresponding to the counter whose count value reached full scale earliest is written into the memory and displayed until the next write. be done.

Moreover, between two adjacent carry signals, it is clear that the digital signal corresponding to the counter that sent out the latter carry signal was applied to terminal P for the longest time than the other signals. be.

That is, when the input digital signal fluctuates frequently due to the influence of noise, the device of the present invention selects the signal that has been applied for the longest time during an automatically determined appropriate period, and selects the signal that has been applied for the longest time, and This will be displayed during the period.

Therefore, the numerical value with the highest probability of being the true radio wave arrival direction is stably displayed over a long period of time, and can be easily read.

Moreover, since the noise component is large, when the measured digital signal is distributed over a wide range, the pulses to be counted are distributed to a large number of counters, and it takes a long time to send out the significant signal.

Therefore, the time required to select a numerical value is automatically increased to ensure accurate value display.

[Brief explanation of drawings]

FIG. 1 is a block diagram of an embodiment of the present invention, and FIG. 2 is a time chart showing the operation of the apparatus of FIG. 1. In the figure, P is the input terminal for the measured digital signal, B is the decoder, MU memory, D is the display, K is the clock pulse generator, Ao, A1...A9U and gate, co, C1...C, In other words, 0 is an or gate.

Claims (1)

[Claims] 1. A decoder to which a digital signal corresponding to the measured azimuth angle at each time is applied and sends out signals from different output terminals according to at least the value of the lower digit of the digital signal, A plurality of counters having the same number of stages are configured so that when one counter sends a carry signal after counting the signals of each output terminal, all the counters are reset at the same time. A display device for a digital azimuth measuring instrument, comprising: a memory device that stores the digital signal each time it is sent; and a display device that constantly displays the signal stored in the memory device.