JP3766341B2 - Radar equipment - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a radar apparatus for observing a target such as a flying object, and more particularly to improvement of a sidelobe canceller (SLC) thereof.
[0002]
[Prior art]
As is well known, the radar apparatus as described above is provided with an SLC (Side Lobe Canceller) function in order to suppress interference waves.
[0003]
This SLC function extracts interference wave components from the beam data of the SLC channel using main beam data including a preset gain and residual power, and subtracts the interference wave components from the main beam data to prevent interference. Canceled.
[0004]
However, in this SLC function, since the gain for extracting the interference wave component is a fixed value, the SLC convergence speed, that is, until the interference is canceled after receiving the interference according to the strength of the interference wave. The speed is different.
[0005]
In other words, when the gain is set in response to the high power interference, the convergence is delayed at the time of the low power interference. Moreover, if the gain is set in response to the small power interference, the high power interference cannot be completely cancelled.
[0006]
In order to cope with this problem, a method of opening the gain adjustment to the operator, that is, a method of manually changing the gain by the operator so that the optimum SLC processing can be performed according to the strength of the interference wave is conceivable. ing.
[0007]
However, it cannot be said that manually inputting a gain is an appropriate method for practical use in an emergency where an interference wave is emitted to the radar device.
[0008]
[Problems to be solved by the invention]
Therefore, the present invention has been made in consideration of the above circumstances, and it is an object of the present invention to provide an extremely good radar apparatus capable of realizing the optimum SLC processing according to the strength of the interference wave with a configuration suitable for practical use. Objective.
[0009]
[Means for Solving the Problems]
The radar apparatus according to the present invention is intended for an apparatus having an SLC function. A plurality of gain calculating means for calculating the gain corresponding to the input beam data by inputting the beam data of the corresponding SLC channel ; Provided corresponding to a plurality of gain calculating means, each of which extracts a plurality of interference wave components based on the gain calculated by the corresponding gain calculating means and the beam data input to the gain calculating means. An adaptive calculation means and a calculation means for adding and subtracting the interference wave components extracted by the plurality of adaptive calculation means from the main beam data are provided.
[0011]
According to the configuration as described above, the gain for extracting the disturbing wave component is made variable according to the strength of the disturbing wave, the situation of the interference, etc., so that the optimum SLC processing according to the strength of the disturbing wave Can be realized with a configuration suitable for practical use.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In FIG. 1, beam data of a plurality of SLC channels # 1, # 2,..., #N are supplied to gain calculation circuits 111, 112,.
[0013]
Each of the gain calculation circuits 111, 112,..., 11N calculates a gain g corresponding to the input beam data, that is, depending on the intensity of the interference wave with respect to the main beam data, the state of interference, or the like. .
[0014]
Generally speaking, the gain g can be expressed as SLC channel beam data Y as expressed by the equation g = α (1 / Y) where Y is the beam data of the SLC channel and α is a predetermined coefficient. The value is inversely proportional.
[0015]
Each of the gain calculation circuits 111, 112,..., 11N outputs the input beam data Y and the gain g calculated by itself to the adaptive arithmetic circuits 121, 122,.
[0016]
The adaptive arithmetic circuits 121, 122,..., 12N generate the weight W based on the input beam data Y, the gain g, and the main beam data X1 including residual power, respectively. Multiply.
[0017]
The output W · Y (interference wave component) of each adaptive arithmetic circuit 121, 122,..., 12N is supplied to the arithmetic result integrating circuit 13. The calculation result integration circuit 13 is supplied with main beam data X0.
[0018]
Then, the calculation result integration circuit 13 adds the outputs W · Y of the adaptive calculation circuits 121, 122,..., 12N, and subtracts the addition result from the main beam data X0 to perform the SLC process. The main beam data X1 is output.
[0019]
The main beam data X1 output from the calculation result integration circuit 13 includes residual power that could not be canceled, and is fed back to the adaptive calculation circuits 121, 122,..., 12N.
[0020]
According to the above-described embodiment, the gain calculation circuits 111, 112,..., 11N are provided, and the gain g corresponding to the beam data of the SLC channels # 1, # 2,. Therefore, the optimum SLC corresponding to the strength of the interference wave can be realized.
[0021]
The gain calculation circuits 111, 112,..., 11N have a simple configuration in which the gain is calculated by calculating the reciprocal of the beam data of the SLC channels # 1, # 2,. Suitable for practical use.
[0022]
FIG. 2 shows FIG. 1 in more detail. First, the gain calculation circuits 111, 112,..., 11N shown in FIG.
[0023]
The normalization & gain calculation circuit 15 includes normalization circuits 151, 152,..., To which beam data Y1, Y2,. 15N.
[0024]
The normalization circuits 151, 152,..., 15N respectively apply Y1 / | Y1 |, Y2 / | Y2 |,..., YN / to the input beam data Y1, Y2,. A normalization process of | YN | is performed, and outputs Y1nor, Y2nor,..., YNnor are obtained.
[0025]
The beam data Y1, Y2,..., YN of the SLC channels # 1, # 2,..., #N and the outputs Y1nor, Y2nor,. YNnor is supplied to the gain calculation circuit 150.
[0026]
The gain calculation circuit 150 calculates the gain g from the beam data Y1, Y2,..., YN, and outputs the gain Y to the outputs Y1nor, Y2nor,. , YNnor.
[0027]
Among these, the multiplication output g · Y1nor is supplied to one input terminal of the multiplication circuit 121 a constituting the adaptive arithmetic circuit 121. The other adaptive arithmetic circuits 122,..., 12N perform the same operation with the same configuration as the adaptive arithmetic circuit 121, and thus the description thereof is omitted.
[0028]
Main beam data X1 is supplied to the other input terminal of the multiplication circuit 121a. The output g · Y1nor · X1 of the multiplication circuit 121a is supplied to the addition circuit 121b, and is cumulatively added to the limit value defined by the Wn limit circuit 121c to generate the weight W1.
[0029]
Thereafter, the weight W1 that has been subjected to the convergence determination by the convergence determination circuit 121d and the beam data Y1 are multiplied by the multiplication circuit 121e to become the output W1 · Y1 of the adaptive arithmetic circuit 121.
[0030]
The outputs W1 · Y1, W2 · Y2,..., WN · YN of the adaptive arithmetic circuits 121, 122,..., 12N are supplied to and added to the adder circuit 13a constituting the arithmetic result integration circuit 13.
[0031]
Then, the output (interfering wave component) of the adding circuit 13a is subtracted from the main beam data X0 by the arithmetic circuit 13b, thereby generating main beam data X1 subjected to SLC processing.
[0032]
The main beam data X1 output from the calculation result integration circuit 13 includes residual power that cannot be canceled, and is fed back to each adaptive calculation circuit 121, 122,..., 12N. Convergence determination results C1, C2,..., CN in the adaptive arithmetic circuits 121, 122,..., 12N are supplied to a post-convergence SLB (Side Lobe Beam) determination circuit 16 and subjected to determination processing. Supplied to the on / off selector.
[0033]
FIG. 3 shows a modification of the above-described embodiment. That is, when the same reference numerals are given to the same parts as those in FIG. 1, each gain calculation circuit 111, 112,..., 11N is connected to the inter-channel gain control circuit.
[0034]
The inter-channel gain control circuit 14 takes in the gain g calculated by each of the gain calculation circuits 111, 112,..., 11N, and selects the maximum gain g among them.
[0035]
The inter-channel gain control circuit 14 supplies the selected maximum gain g to all the gain calculation circuits 111, 112,..., 11N, and the outputs of the gain calculation circuits 111, 112,. The gain is g.
[0036]
That is, control is performed so that the same maximum gain g is output from all gain calculation circuits 111, 112,..., 11N to the respective adaptive arithmetic circuits 121, 122,.
[0037]
In this way, the gain g used in each adaptive arithmetic circuit 121, 122,..., 12N is unified to the maximum gain g among the gains g calculated by each gain calculation circuit 111, 112,. Then, it has been experimentally revealed that an appropriate SLC can be performed according to the strength of the interference wave.
[0038]
When the SLC channel is formed symmetrically in the positive and negative radial directions with respect to the main lobe, if the same gain g is used for the paired SLC channel, a good SLC is caused by overreaction. May not be done. In this case, it is desirable to reduce the gain of one of the paired SLC channels to about half by the inter-channel gain control circuit 14 described above.
[0039]
More specifically, regarding the calculation of the gain g, for the gain Gn (k) (where n = 1 to N) with the number of SLC channels = N and the range = k,
Gn (k) = 1 / {| Yn (k) | × 4 × gsafe}
Is established. Here, gsafe: safety coefficient = 1, 2, 4 can be set.
[0040]
And g = min [G1 (k), G2 (k),..., GN (k)]. However, the upper limit of g = ^2-8 to ^2-5 can be set. g × Ynnor is output to the adaptive computing cell of SLC channel n.
[0041]
FIG. 4 shows still another modification of the above-described embodiment. That is, the same parts as those in FIG. 3 are denoted by the same reference numerals, and gain calculation circuits 111, 112,..., 11N are incorporated in the adaptive arithmetic circuits 121, 122,.
[0042]
In this case, each of the gain calculation circuits 111, 112,..., 11N calculates the gain g from the residual power included in the main beam data X1 output from the calculation result integration circuit 13, and uses it for adaptive calculation. Yes.
[0043]
The present invention is not limited to the above-described embodiment, and can be variously modified and implemented without departing from the scope of the invention.
[0044]
【The invention's effect】
As described above in detail, according to the present invention, it is possible to provide an extremely good radar apparatus that can realize the optimum SLC processing according to the strength of the interference wave with a configuration that is sufficiently suitable for practical use.
[Brief description of the drawings]
BRIEF DESCRIPTION OF DRAWINGS FIG. 1 is a block configuration diagram shown to describe an embodiment of the present invention.
FIG. 2 is a block configuration diagram shown for explaining details of a main part in the embodiment.
FIG. 3 is a block configuration diagram shown for explaining a modification of the embodiment.
FIG. 4 is a block configuration diagram shown for explaining another modification of the embodiment.
[Explanation of symbols]
111 to 11N: Gain calculation circuit,
121 to 12N: Adaptive arithmetic circuit,
13: Calculation result integration circuit,
14: Interchannel gain control circuit,
15: Normalization & gain calculation circuit,
16: SLB determination circuit after convergence.

Claims (7)

In radar equipment with SLC (sidelobe canceller) function,
A plurality of gain calculating means which are provided corresponding to a plurality of SLC channels , each of which receives the beam data of the corresponding SLC channel and calculates a gain corresponding to the input beam data ;
Provided corresponding to the plurality of gain calculating means, each of which extracts an interference wave component based on the gain calculated by the corresponding gain calculating means and the beam data input to the gain calculating means. A plurality of adaptive computing means;
A radar apparatus comprising: an arithmetic means for adding and subtracting the interference wave components extracted by the plurality of adaptive arithmetic means from the main beam data. It said gain calculating means, the radar apparatus according to claim 1, wherein the calculating the gain to be inversely proportional to the beam data of the SLC channel. In radar equipment with SLC (sidelobe canceller) function,
Gain calculating means for calculating gains corresponding to beam data of a plurality of SLC channels,
An interference means component is extracted based on the gain calculated by the gain calculation means, and a calculation means for subtracting from the main beam data,
Said gain calculating means, among the gain calculated respectively in accordance with the beam data of a plurality of SLC channels, the biggest feature and, Relais over said output to the arithmetic unit gain as the gain for all SLC channel Device. In radar equipment with SLC (sidelobe canceller) function,
Gain calculating means for calculating gains corresponding to beam data of a plurality of SLC channels,
An interference means component is extracted based on the gain calculated by the gain calculation means, and a calculation means for subtracting from the main beam data,
Said gain calculating means, when symmetrically SLC channel is formed in the radial direction opposite the main lobe as a reference, wherein a, Relais over that to apply different gain to SLC channel to be paired Da device . The radar apparatus according to claim 1 , wherein the extraction of the interference wave component by the adaptive calculation means is further based on residual power included in main beam data after SLC processing output from the calculation means . In radar equipment with SLC (sidelobe canceller) function,
Calculation means for calculating gains corresponding to a plurality of SLC channels from the residual power included in the main beam data after the SLC processing, extracting an interference wave component based on the calculated gains, and subtracting it from the main beam data Comprising
The arithmetic unit applies a maximum gain among gains calculated corresponding to a plurality of SLC channels, respectively, as a gain of all SLC channels . In radar equipment with SLC (sidelobe canceller) function,
Calculation means for calculating gains corresponding to a plurality of SLC channels from the residual power included in the main beam data after the SLC processing, extracting an interference wave component based on the calculated gains, and subtracting it from the main beam data Comprising
It said calculating means, if symmetrically SLC channel is formed in the radial direction opposite the main lobe as a reference, a radar, characterized in that to apply a different gain to SLC channels paired device.

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