JPH11183583A - Azimuth-displaying device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To intuitively determine probability of a measurement azimuth. SOLUTION: A circular azimuth scale 13 with a small circle 12 indicating a measurement position as a center is shown, a PWU evaluation function curve 14 of a direction detector by the music method is displayed by distance in a center direction in reference to its azimuth scale circle 15 for each azimuth, further a frequency where a measurement azimuth in each azimuth is obtained is shown by a bar graph display 17i in a center direction in reference to the circle 15, a current instantaneous azimuth is displayed as radial lines 16d1, 16d2, and 16d3, and further the radius of a circular cursor 18 is changed from small to large values or from large to small values and its azimuth is displayed when the radius matches the peak of the function 14 or the bar graph display 17i.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an azimuth display device applied to, for example, a device which can simultaneously measure the directions of arrival of a plurality of radio waves and displays the azimuth of the arriving radio waves.

[0002]

2. Description of the Related Art As a conventional azimuth display device of this type, for example, a device to which the music method is applied is disclosed in Japanese Patent Application No. Hei.
No. 205521, "Direction Finding", the applicant has proposed. This azimuth display device displays the azimuth from 0 to 360 ° on the horizontal axis, the value of the PMU evaluation function in the music method or the reception frequency, that is, the azimuth statistical value, on the vertical axis, and displays it on the vertical axis. By moving the parallel cursor along the horizontal axis and matching the peak value of the evaluation function or the statistical value, a likely direction is obtained.

[0003]

Conventionally, since an evaluation function indicating the certainty of a measurement direction and a statistical value are displayed in a rectangular coordinate system, the measurement direction with respect to a measurement position cannot be obtained intuitively. In addition, there is a problem that it is difficult to intuitively understand the relationship between the display of the statistical value and the display of the current instantaneous measurement direction. Further, there is another problem that it is difficult to distinguish a required signal from an unnecessary signal such as noise.

[0004]

According to the present invention, an azimuth scale is displayed on a circumference centered on a measurement position, and the likelihood of a measurement azimuth is determined with reference to the circumference centered on the center. The indicated evaluation function value or the statistical value of the measurement azimuth is displayed over 360 degrees as the distance to the center.

Further, the orientation at the peak value of the evaluation function value or the peak value of the statistical value is displayed as a radial straight line with respect to the center. Further, the radius of the circular cursor centered on the center is changed, a coincidence between the cursor and the peak is detected, and the azimuth thereof is displayed. Further, the current instantaneous measurement direction is displayed as a radial straight line with respect to the center.

Alternatively, the instantaneous measurement azimuth is displayed as a radial azimuth line with respect to the center, and at least one of the length, thickness, and color is changed in accordance with the likelihood of the signal.

[0007]

FIG. 1 shows a display example displayed on a display surface of an azimuth display device according to the present invention. A small circle 12 indicating a measurement position is displayed on the display surface 11, and an azimuth scale 13 of 0 ° to 360 ° is displayed along a circumference around the measurement position circle 12. Normally 0 ° is the upper end and 0 °
Is selected in the north direction, or in the case of a moving object such as a ship, in the forward direction, and is scaled clockwise.

In this embodiment, a function indicating the certainty of the measurement direction, and in the case of the music method, a PMU evaluation function 14
Is the circumference around the center small circle 12, in this example, scale 1
3 is displayed as the distance from the inner circle 15 to the small circle 12. Evaluation function value P at each angle from 0 ° to 360 °
The maximum value among 0, P1,... P359 is PMAX,
The evaluation function value of the degree i is Pi, the radius of the small circle 12 is r ₀ , the radius of the inner circumferential circle 15 of the azimuth scale is r ₀ + r, and the center of the small circle 12 is the origin x = 0, y = If 0, P _i
Coordinates x _i of, y _i is obtained by the following equation.

X _i = (r ₀ + r (1−P _i / PMAX)) sin i ° y _i = (r ₀ + r (1−P _i / PMAX)) cos i ° 0 ° calculated in this way A polygonal line having an inflection point at each evaluation function value coordinate (x0, y0) of 359 ° to (x359, y359) is displayed as the evaluation function curve 14.

The current instantaneous measurement directions D1, D2,.
The current azimuth lines 16d1, 16d2, and 16dm are displayed as Dm as a straight line in the radial direction with the small circle 12 as the center. In the figure, three current azimuth lines 16d1, 16d2, and 16d3 are displayed. Current measurement direction Dj (j = 1, 2,...,
The following coordinates are calculated for m). x1 = r0 sinDj y1 = r0 cosDj x2 = (r0 + r) sinDj y2 = (r0 + r) cosDj The current direction line 16dj of the current direction Dj is displayed as a line segment connecting the point (x1, y1) and the point (x2, y2). .

Since the azimuth at the peak of the PMU evaluation function in the music method is the measurement azimuth, the peak point of the evaluation function curve 14 is defined as the current azimuth line 16d1, 16d2,1.
6d3 passes. Furthermore, in this example, the direction statistics are
With reference to a circumference 15 centered on the small circle 12, the small circle 12
Displayed as distance to side. 0 ° to 359 in the illustrated example
Each degree φ0, φ of the azimuth measured respectively for °
.., Φ359, that is, the frequency is incremented by 1 for the measurement direction obtained for each measurement, and when the maximum frequency is φMAX, the next coordinate is calculated for each direction i degree. .

X1 = (r0 + r) sin i ° y1 = (r0 + r) cos i ° x2 = (r0 + r (1-φi / φMAX)) sin i ° y2 = (r0 + r (1-φi / φMAX)) cos i ° Point (x1, y1) and point (x2, y2) for i degree
Are displayed as the statistical value line 17i. That is, the point (x1, y1) is located on the reference circumference 15 and the point (x1, y1)
The distance from (1, y1) to the point (x2, y2) corresponds to the frequency at which the measurement azimuth was obtained at i degrees, that is, the statistical value.

In the example of FIG. 1, the current directions 16d1, 16d2,
A measured azimuth frequency distribution appears in each of the three neighborhoods of 16d3. In the example of FIG. 1, a circular cursor 18 centering on the small circle 12 is displayed, and the radius of the circular cursor 18 is changed.
When the peak of the evaluation function curve 14 or the peak of the frequency distribution coincides, this is configured to be detected. The radius of the circular cursor _{18 d = r 0 + r (} 1-P / PMAX)
Is calculated and displayed.

When the circular cursor 18 is gradually increased from the radius r0 of the small circle 12, the azimuth of the peak of the evaluation function curve 14 detected first is indicated by a one-dot chain line 2 as shown in FIG.
1 is displayed, and the azimuth of the peak of the evaluation function curve 14 which is first detected when the circular cursor 18 gradually decreases from the radius r0 + r, that is, the reference circle 15, is displayed as a broken line 22.

If the diameter of the circular cursor 18 is to be increased, the display section 2 at the lower right of the display surface 11 is displayed as "Peak search △".
A marker (not shown) may be located at 5 and clicked. Conversely, if the diameter of the circular cursor 18 is to be reduced, the display section 26 "Peak Search #" may be clicked. The value of the radius of the circular cursor 18 when a peak is detected by the peak search is displayed on the cursor value display section 22 at the lower left of the display surface 11. From this value, it is possible to know the certainty of the measurement direction. P / P instead of this radius
MAX may be displayed.

Although not shown in the figure, the azimuth of the peak may be numerically displayed. In addition, the type of display of these peak directions may be different from the solid line, the dotted line, the dashed-dotted line, and the like. This peak search may be performed on the azimuth statistics 17i as shown in FIG. In this case, the radius of the circular cursor 18 is obtained by calculating d = r ₀ + r (1−φ / φMAX). The display unit 27 may display the frequency value φ / φMAX instead of the radius. Orientation statistics display 17
i may be displayed as an envelope instead of a bar graph.

A display device for performing the various displays described above is configured as shown in FIG. 4, for example. CPU 31, RAM 32 used for work, etc., and RO storing programs and the like
M33 is connected to the bus 34, and a music type direction finder 35 is connected to the bus 34 via an external communication device controller 36 as an azimuth measuring device for simultaneously measuring a plurality of directions. The keyboard 41 is connected to the bus 34 via the mouse controller 39, the display 41 and the video memory 42 are connected to the bus 34 via the video controller 43, and the external storage device 44 is connected to the bus via the external storage device controller 45. 34.

A display process is performed by the CPU 31 reading and decoding the program. In this processing procedure, for example, as shown in FIG.
1) It is checked whether or not measurement data has been input from the direction finder 35 (S2). If there is data input, the azimuth angle frequency distribution is calculated (S3), and a display image corresponding to the data in the data area for erasure. Is deleted from the video memory 42 (S
4), a display image is created from the data in the display data area and written to the video memory 42 (S5), and the data in the display data area is transferred to the erasure data area, and the process returns to step S2 (S6).

If no measurement data is input from the direction finder 35 in step S2, it is checked whether there is an instruction to search for a lower peak, that is, an instruction to gradually decrease the radius of the circular cursor 18 from the maximum value (S7). If there is an instruction, the next downward peak search is executed, and the process proceeds to step S4 (S4).
8). If the lower peak search is not instructed in step S7, it is checked whether an upper peak search is instructed (S9). If the upper peak search is instructed, the next upper peak search is executed and the process proceeds to step S4 (step S4). S10). If it is not instructed in step S9, the process returns to step S2.

FIG. 6 shows still another embodiment of the present invention.
Parts corresponding to those in FIG. 1 are denoted by the same reference numerals. This example is an example where the measurement result input to the external communication device controller 36 is shown in FIG. Azimuth lines 16d1, 16d2, 16
d3 has a length corresponding to the input (received) power value and a width proportional to the corresponding peak value of the PMU evaluation function. Now, n signal strength sets (Lev1, Lev2,
.., Levn) to the lengths d1, d2,.
Is determined as follows. The minimum signal strength that can be displayed is Levmi
n, the maximum displayable signal strength is Levmax, and dj =
Levi / (Levmin−Levmax) (j = 1, 2, 2)
.., N), and if the radius of the small circle 12 is r ₀ and the radius of the outer circle 15 is r ₀ + r, xj1 = r ₀ sin Dj yj1 = r ₀ cos Dj xj2 = ((r ₀ + r− r ₀ ) dj + r ₀ ) sin Dj yj2 = ((r ₀ + r−r ₀ ) dj + r ₀ ) cos Dj A line segment having these two xy coordinates as end points is displayed on the display surface.

The width of the azimuth line 16dj is made different according to the PMU evaluation value. FIG. 8A shows a conversion table between the PMU evaluation value and the line width. In this example, the range 0 to Lmax of the PMU evaluation value is divided into five ranges, and the larger the PMU evaluation value, the thicker the line width.
In the case of d1, the PMU evaluation value is 53, so the line width is read from FIG. 8A to 3 and the width of the azimuth line 16d1 is set to 3.

The color of the azimuth line may be changed according to the PMU evaluation value. For example, in FIG. 8B, a range 0 to PMUmax of the PMU evaluation value is divided into four equal ranges, and colors 1 to 4 are sequentially assigned to the four ranges. For example, as shown in FIG. 9, the azimuth line 16d1 is displayed in color 3 because the PMU evaluation value is 53, and the azimuth line 16d2 is displayed in color 1 because the PMU evaluation value is 21.

In the above description, the length of the azimuth line is changed according to the input power (signal strength) as the certainty of the input signal.
The width or color of the azimuth line was changed according to the corresponding PMU evaluation value. PMU corresponding to bearing obtained by signal processing
The length of the azimuth line may be changed according to the evaluation value, and the width or color of the azimuth line may be changed according to the input power (signal strength) value. The azimuth line 16di in this case is determined as follows. The minimum displayable PMU value is PMUmin, the maximum displayable PMU value is PMUmax, and the azimuth angles D1, D2,.
PMU values corresponding to Dn are PMUd1, PMUd2,
…, The length d1, of the azimuth line proportional to PMUdn
For d2,..., dn, dj = PMUdj / (PMUma
calculates the _{x -PMUmin), xj1 = r 0} sin Dj yj1 = r 0 cos Dj xj2 = ((r 0 + r-r 0) dj + r 0) sin Dj yj2 = ((r 0 + r-r 0) dj + r 0) cos Dj A line segment having these two x, y coordinates as end points is displayed on the display surface.

As shown in FIG. 8A, 0 to Lev of input power
max is divided into five ranges, and line widths 1 to 5 are sequentially allocated to the respective ranges.
What is necessary is just to determine the width of j. Similarly, as shown in FIG. 8D,
Colors 1 to 5 are sequentially assigned to each range obtained by dividing 0 to Levmax into five, and the display color of the azimuth line 16dj is determined with reference to this conversion table.

The present invention can be applied not only to the direction finder using the music method but also to the direction of arrival measurement display of other waves, and particularly to the display of an apparatus capable of measuring the direction of waves arriving simultaneously from a plurality of directions. .

[0026]

According to the present invention, the circular azimuth scale centering on the measurement position is displayed, and an evaluation function value indicating the certainty of the measurement azimuth in each azimuth is obtained, and the statistical value of the measurement azimuth is displayed. You can intuitively understand the accuracy of the measurement direction.
Further, when the direction of arrival changes, the width of the change and the magnitude of the change can be known, and in that case, the correspondence with the direction can be immediately established.

Further, by performing a peak search using a circular cursor, the most likely direction is automatically displayed. By displaying the present instantaneous measurement azimuth radially from the center of the circular azimuth scale simultaneously with the indication of the certainty of the azimuth, the certainty can be intuitively known.

According to still another embodiment of the present invention, one of the evaluation value indicating the likelihood and the input power value corresponds to the length of the instantaneous measurement azimuth line, and the other corresponds to the line width or display color. Therefore, the azimuth can be read instantaneously, and the signals can be easily distinguished intuitively. This makes it easy to distinguish whether the displayed azimuth line is due to a signal or noise.

[Brief description of the drawings]

FIG. 1 is a diagram showing a display example by an azimuth display device of the present invention.

FIG. 2 is a diagram showing another example.

FIG. 3 is a diagram showing still another example.

FIG. 4 is a block diagram showing a configuration example of a device of the present invention.

FIG. 5 is a flowchart showing an example of a processing procedure of the apparatus of the present invention.

FIG. 6 is a diagram showing still another display example by the azimuth display device of the present invention.

FIG. 7 is a diagram showing a measurement result example.

FIG. 8 is a diagram showing various examples of the probability and the azimuth line width or the azimuth line color conversion table.

FIG. 9 is a diagram showing still another display example according to the present invention.

Claims (6)

[Claims] 1. An azimuth display device in which an evaluation function indicating the likelihood of azimuth measurement is such that a function value in each azimuth is represented by a distance in a radial direction with the measurement position being substantially at the center. 2. An azimuth display device in which azimuth statistical values obtained from azimuth measurement results are displayed from a circumference centered on a measurement position toward the center. 3. The azimuth display device according to claim 1, wherein the azimuth of the peak corresponding to the likelihood of the measurement azimuth is displayed as a straight line in the radiation direction from the center. 4. A means for displaying a circular cursor centered on the center, a means for changing the radius of the circular cursor to detect coincidence with the certainty peak, and displaying the coincident direction. The azimuth display device according to any one of claims 1 to 3, further comprising means. 5. The azimuth display device according to claim 1, wherein the instantaneous measurement azimuth is displayed as a straight line in a radial direction from the center. 6. An azimuth display device in which an instantaneous measurement azimuth is displayed as a azimuth line radial to a center, wherein the azimuth line has at least a length, a thickness, or a color according to the likelihood of the signal. An azimuth display device, wherein any one of them is changed.