JPH02198378A - Displaying method of frequency spectrum - Google Patents

Abstract

PURPOSE:To restrict the amount of displaying informations thereby to easily detect a target and to analyze a target signal by removing a frequency spectrum and directional data of a sound from a sound source present in the designated direction and within the designated directional area from on a display. CONSTITUTION:A frequency spectrum data 101 and a directional data 102 from a frequency analyzing unit 5 are input to a frequency spectrum data unit 2 and a directional data selecting unit 3 respectively. On the other hand, in a directional area setting unit 1, a selected directional area data 103 is calculated from the input designated directional data 107 and designated directional area data 108 with an allowance of the designated directional area kept around the designated direction, which data is sent to the selecting unit 3. In consequence, the selecting unit 3 extracts a selected directional data 106 without the selecting area and sends the same to a display unit 4. At the same time, the unit 3 sends a selected frequency data 104 corresponding to the designated direction to the data unit 2. The data unit 2 outputs only a selected frequency spectrum data 105 based on the data 104 to the display unit 4. The display unit 4 displays the data 105 and 106, removing the display of a frequency spectrum of the direction in the specified area.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a frequency spectrum display method, and in particular, it extracts frequency spectra by frequency analysis of underwater acoustic signals received by a sonobuoy, and displays the frequency spectra for each individual frequency spectrum. The present invention relates to a frequency spectrum display method that calculates azimuth data indicating the direction of arrival and displays it together with a frequency spectrum.

[Conventional technology]

Conventionally, this type of frequency spectrum display method has displayed all frequency spectra and directions after frequency analysis on a CRT, recording paper, or the like.

[Problem to be solved by the invention]

The conventional frequency spectrum display method described above displays all frequency spectra and corresponding orientations after frequency analysis. For this reason, the frequency spectrum and corresponding direction are displayed even for sound sources that are clearly identified as not being targets based on information from other sensors such as radar and frequency spectrum analysis, etc., so there is redundancy in the displayed amount. This has the disadvantage that it often causes the important target frequency spectrum to be overlooked, making it difficult to analyze the target frequency spectrum.

SUMMARY OF THE INVENTION An object of the present invention is to provide a frequency spectrum display method that eliminates the above-mentioned drawbacks, eliminates unnecessary frequency spectrum display, and ensures display of a target frequency spectrum.

[Means to solve the problem]

The method of the present invention is a frequency spectrum display method in which azimuth data indicating the direction of arrival is calculated for each detailed frequency spectrum obtained by frequency analysis of an underwater acoustic signal received by a sonobuoy, and the frequency spectrum is displayed together with the corresponding azimuth. , a selection azimuth range setting means for setting a selection azimuth range having an arbitrary azimuth range centered on a selected arbitrary specified azimuth, and a selection for selecting and displaying a frequency spectrum existing outside the selected azimuth range and corresponding azimuths. and a display means.

〔Example〕

Next, the present invention will be described in detail with reference to the drawings.

The embodiment shown in FIG. 1 includes an azimuth range setting unit 1 as a selection azimuth range setting means for setting a selection azimuth range having an arbitrary azimuth range centered on an arbitrary designated azimuth selected by an operator; A frequency spectrum data selection section 2 constituting a selection display means for selecting and displaying frequency spectra and corresponding orientations existing outside of the . In addition to the azimuth data selection section 3 and the display section, it also includes a frequency analysis section 5.

Next, the operation of this embodiment will be explained.

Frequency spectrum data 101 and orientation data 102 output from frequency analysis section 5 are input to frequency spectrum data selection section 2 and orientation data selection section 3, respectively.

On the other hand, the specified azimuth data 107 and the specified azimuth range data 108 are set by the operator and input into the azimuth range setting section 1, and the selected azimuth range data 103 having the specified azimuth as the center and the width of the specified azimuth range is calculated. It is input to the selection section 3.

The azimuth data selection unit 3 extracts selected azimuth data 106 outside the range based on the selected azimuth range data 103 and outputs it to the display unit 4, and also outputs the frequency corresponding to the azimuth data as selected frequency data 104. The 0-frequency spectrum data selection unit 2 outputs to the spectrum data selection unit 2 only the frequency spectrum specified by the selection frequency data 104 as the selected frequency spectrum data 1.
It is output to the display unit 4 as 05.

The display unit 4 displays selected frequency spectrum data 105 and selected orientation data 106.

In this way, it is possible to eliminate the display of a frequency spectrum over a specific range of directions that does not need to be displayed.

〔Effect of the invention〕

As explained above, the present invention eliminates unnecessary frequencies that have been confirmed not to be the target by removing from the display the frequency spectrum and azimuth data of the sound generated by the sound source existing in the specified azimuth and azimuth range. Since the spectrum can be removed from the display, the amount of displayed information can be significantly suppressed, which has the effect of significantly facilitating target detection and target signal analysis.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing the configuration of an embodiment of the present invention. DESCRIPTION OF SYMBOLS 1... Direction range setting section, 2... Frequency spectrum data selection section, 3... Direction data selection section, 4... Display section, 5... Frequency analysis section.

Claims (1)

[Claims] A frequency spectrum display that calculates azimuth data indicating the direction of arrival for each individual frequency spectrum obtained by frequency analysis of an underwater acoustic signal received by a sonobuoy, and displays the frequency spectrum along with the corresponding azimuth. The method includes: a selection azimuth range setting means for setting a selected azimuth range having an arbitrary azimuth range centered on a selected arbitrary specified azimuth; and selecting and displaying a frequency spectrum and corresponding azimuths existing outside the selected azimuth range. A frequency spectrum display method comprising: a selection display means; and a frequency spectrum display method.