JP2886298B2 - Pulse train classification device - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pulse train classifying device that classifies pulse data after receiving and detecting a laser wave and digitizing the same according to each mode.

[Prior Art] Conventionally, as this kind of pulse train classification device, for example,
There are those as shown in FIGS. 4 and 5.

In FIG. 4, 1 is an antenna for radio wave reception, 2 is a receiver, 3 is a parameter measuring device for measuring parameters for each received pulse, and 4 is a parameter for classifying the measured parameters for each specific pulse group. The classifier 5 is a processor that controls the parameter classifier 4. Here, the parameters to be measured include frequency, amplitude, pulse width, AOA (Angle Of Arrival), TOA (Time Of Arriva).
l) and so on.

FIG. 5 shows the configuration of the parameter classifier 4,
41A is an upper limit memory for storing the upper limit value of the parameter for each pulse group, 41B is a lower limit memory for storing the lower limit value of the parameter for each pulse group, and 42 is the measured parameter and its upper and lower limits. A parameter comparison circuit 43 for comparing a value with a value is a cell address generation circuit 43 for generating a cell address of a pulse group.

The upper limit value and the lower limit value stored in each of the memories 41A and 41B are basically fixed unless a specific operation is performed from the outside.

The parameters of the pulses received by the antenna 1 and the receiver 2 are measured by the parameter measuring device 3. When this parameter 42a is given to the parameter comparison circuit 42, the cell address 43b of the specific pulse group is output from the cell address generation circuit 43 to the upper limit memory 41A and the lower limit memory 41B, and the pulse group corresponding to this address is output. The upper limit value and the lower limit value are output from the upper limit value memory 41A and the lower limit value memory 41B to the parameter comparison circuit 42, respectively.

The comparison circuit 42 compares the parameter with the upper limit value and the lower limit value. If the parameter is within the range of the upper limit value and the lower limit value, the cell address generation circuit 43 outputs the cell address of the corresponding pulse group to the processor 5 as the match address 43a.

[Problems to be Solved by the Invention] However, in such a conventional pulse train classifying apparatus, the upper limit value and the lower limit value of the pulse group are basically fixed. Changes, the parameter changes, and it may be determined that the pulse group does not belong to the same pulse group, and there is a problem that accurate classification may not be performed.

Another problem is that when a pulse from an unknown pulse source such as a new radio wave source is input, this pulse may not be classified at all.

The present invention has been made in view of such conventional problems, and has as its first object to provide a pulse train classifying apparatus capable of accurately classifying pulses even when an external environment changes. .

A second object of the present invention is to provide a pulse train classifying apparatus capable of classifying even a pulse from an unknown pulse source.

[Means for Solving the Problems] To solve the above problems, the present invention provides a parameter measuring means for measuring at least a pulse arrival direction as a parameter of a received pulse; A permissible range storage unit for storing a permissible range of the parameter, and a permissible range stored by the permissible range storage unit,
Parameter determining means for searching an allowable range including the parameters of the reception pulse; and when the parameter determining means finds an allowable range including the parameters of the reception pulse, a pulse group corresponding to the allowable range is determined by the reception pulse. A pulse classifying means for recognizing a pulse group to which the received pulse belongs, and a new pulse group in which the received pulse is classified when the parameter determining means cannot find an allowable range including a parameter of the received pulse. And a pulse group setting means for setting an allowable range of parameters for the new pulse group in the allowable range storage means.

Here, the correction means, the permissible range of the pulse group to which the received pulse belongs, based on the number of pulses of the pulse group including the received pulse and the average value and variance of the parameter,
It is preferable to configure to correct.

The correction means may be configured to decrease the width of the allowable range as the number of pulses in the pulse group increases.

[Operation] When a certain pulse is received, a predetermined parameter of the pulse is measured by the parameter measuring means.

In the parameter determination means, the measured parameter is
It is determined whether any of the plurality of pulse groups is within the allowable range stored in the allowable range storage means.

The pulse classification means recognizes a pulse group to which the received pulse belongs based on the result of the determination.

When the parameter determining means determines that the measured parameter is not within the allowable range of any of the pulse groups, the pulse group setting means sets a new allowable range in the allowable range storage means and sets the pulse classification. A new pulse group is set in the means. Then, when the pulse belonging to the new pulse group is received again, this pulse is classified based on the newly set allowable range.

The allowable range of the pulse group to which the received pulse belongs is corrected by the correction unit based on the number of pulses of the pulse group including the received pulse, the average value and the variance of the parameter.

 The correction of the allowable range of the parameter will be described.

Assuming that the probability density function of the sample data of the pulses belonging to the pulse group has a substantially Gaussian distribution, it is best to obtain the allowable range of the pulse group from the average value and the variance.

Therefore, assuming that the average value of the parameter at the hit count value h is E _h ｛x｝ and the allowable value is W _h , the allowable range D _h is E _h ｛x｝ −w _h ≦ D _h ≦ E _h ｛x｝ + it can be expressed as W _h.

Assuming that the difference between the input parameter x _i and the average value E _h {x} of the parameters at the hit count value h is Δx _h , the average value E at the hit count value h + 1 including the input parameter x _i is E
_{h + 1} {x} is It can be expressed as.

Also, the variance σ ² is given by σ ² = E 2x ² ｝ − (E ｛x ^２ ) ² , so the variance σ at the hit count value h + 1
² _{h + 1} is Becomes

Since the allowable value W _h can be obtained from the standard deviation σ _h and the hit count value h, the allowable value W _h can be expressed as w _h = F ₁ (h, σ _h ).

Here, the allowable value w _{h + 1} at the hit count value _{h + 1} is
Can be represented by the hit count value h and the standard deviation sigma _h and [Delta] x _h, and since the standard deviation sigma _h can be converted to an acceptable value W _h by a function F _1, tolerance w _{h + 1} is, w _{h + 1} = F ₂ (h, w _h , Δx _h ).

Therefore, a function F ₂ having h, W _h , and Δx _h as variables is determined in advance.
Is prepared, a new allowable value wh _{+ 1} can be easily obtained.

Based on this new allowable value, a newly corrected allowable range _{Dh + 1} is determined as follows, and the value is stored in the allowable range storage means.

E _{h + 1} ｛x｝ -w _{h + 1} ≦ D _{h + 1} ≦ E _{h + 1} ｛x｝ + w _{h + 1 When a} new pulse is received, the corrected allowable range D _{h + 1}
, And the new pulse is classified.

Therefore, since the allowable range of the parameter is updated every time a pulse is received, even if the external environment changes,
Pulses belonging to a specific pulse group can always be accurately classified.

Also, even if a pulse is received from an unknown pulse source,
By providing the pulse group setting means, an allowable range for a new pulse is newly set, and when this pulse is received again, based on the newly set allowable range,
This pulse can be classified.

Example An example of the present invention will be described below with reference to FIGS.

A first embodiment of the pulse train classifying apparatus will be described with reference to FIG.

In FIG. 1, 1 is an antenna for radio wave reception, 2 is a receiver, 3 is a parameter measuring device for measuring a parameter for each received pulse, and 4 is a parameter for classifying the measured parameter for each specific pulse group. The classifier 5 is a processor that controls the parameter classifier 4.

As described above, the basic configuration of the pulse train classification device of the present embodiment is almost the same as the conventional one, but the configuration of the parameter classifier 4 is different from the conventional one.

 The configuration of the parameter classifier 4 will be described.

Reference numeral 401 denotes an average value memory that stores an average value of a predetermined parameter for a pulse for each pulse group, and reference numeral 402 denotes an allowable value memory that stores an allowable value for a measured parameter to belong to a specific pulse group for each of a plurality of pulse groups. 403 is 408a
Is a parameter determination circuit for determining whether or not a parameter input from the range is within a range of an allowable value of any pulse group.

404 is a hit count memory representing the number of pulses received in each pulse group, 405 is a function ROM for calculating the correction amount of the average value of the parameters and correcting the allowable value, 406 is a control circuit for controlling the processing sequence, 407 is various memories A cell address generation circuit for designating an address of a cell for each pulse group set in 408, a multiplexer 408 for selecting an input parameter from the 408a and an output from the function ROM 405, and an incrementer 409 for setting the hit count value to +1 , 410 is a register for holding the difference between the input parameter and the average value of the parameter, 411 is a register for holding an allowable value when it is determined by the parameter determination circuit 403 to be within the allowable value range, and 412 is a register for the allowable value. A register 413 holds a hit count value of a pulse group corresponding to the permissible value when it is determined to be within the range, and 413 holds an output of the function ROM 405. A register 414 for transferring the cell address of the pulse group corresponding to the allowable value to the processor 5 when it is determined that the allowable value is within the range of the allowable value; and 416, an initial value of the allowable value given from the processor 5. Register holding value, 415
Is a multiplexer for selecting the corrected allowable value and the initial value of the allowable value.

In the above configuration, the permissible range storage means is constituted by the average value memory 401 and the permissible value memory 402, the parameter judgment means is constituted by the parameter judgment circuit 403, and the correction means is constituted by the function ROM 405. The pulse classifying means and the pulse group setting means are constituted by the processor 5.

 Next, the operation of the present embodiment will be described.

The parameter of the received pulse is a parameter measuring device 3
Is supplied from the 408a to the parameter determination circuit 403 via the multiplexer 408, the cell address generation circuit 407 outputs the cell address (n) of the specific pulse group to the average value memory 401 and the allowable value memory 402. Then, the average value E _h {x} and the allowable value W _h are output therefrom to the parameter determination circuit 403.

The parameter determination circuit 403 determines whether or not the condition | E _h ｛xx− _xi | ≦ W _h is satisfied. If the condition is not satisfied, an increment signal is output to the cell address generation circuit 407. It is determined whether or not the above condition is satisfied with respect to the average value and the allowable value of the cell address (n + 1) newly designated by the cell address generation circuit 407. If the condition is satisfied, the cell address where the condition is satisfied is set in the register 414, the cell address is output to the processor 5, and the average value E _h {x} and the allowable value W of the group of pulses for which the condition is satisfied are satisfied. _Move to the sequence for correcting _h .

The processor 5 recognizes the pulse group to which the received pulse belongs from the plurality of pulse groups based on the cell address output from the register 414.

When the sequence proceeds to the correction sequence, the parameter determination circuit 403
Δx _h (= x _i −E _h {x}) between the input parameter x _i output from and the average value E _h {x} is set in the register 410, and the allowable value W _h is set in the register 411. . The hit count value h is set in the register 412.

The function ROM 405 calculates the average correction data from the values of the registers 410, 411, and 412. Is calculated, and the allowable value _Wh is corrected.

 The correction of the allowable value is performed as follows.

Assuming that the allowable value before correction is W _h and the allowable value after correction is W _{h + 1 the} standard deviation is σ, σ _{h + 1} is given by the above-described equation (1). Assuming that W = 3σ, the corrected allowable value W _{h + 1} is When the output data of the function ROM 405 is designated as the average value correction data by the designation signal 406a from the control circuit 406, the average value correction data is stored in the register 413. Is set.

Average correction data Is a parameter determination circuit 403 via a multiplexer 408.
Is added to the average value E _h {x} stored therein, and a new average value is added. And the average value of the average value memory 401 is also updated to a new average value E _{h + 1} {x}.

Next, when the corrected allowable value data is specified by the specifying signal 406a from the control circuit 406, the corrected allowable value Wh _{+ 1} is set in the register 413.

The corrected allowable value W _{h + 1} is input to the allowable value memory 402 via the multiplexer 415, and the stored allowable value is updated.

At this time, the hit count value incremented by the incrementer is stored in the hit count memory 404.

If the input parameter x _i is not included in the tolerance of all registered pulse groups, the processor 5
The initial value of the allowable value is set in the register 416, and the value of the input parameter x _i and the initial value of the allowable value are stored in the empty cells of the average value memory 401 and the allowable value memory 402 specified by the cell address generation circuit 407, respectively. Is done. The output value 1 from the incrementer 409 is stored in the hit count memory 404.

When the above processing is completed, the same processing is repeated for the next input parameter. Next, when it is determined by the parameter determination circuit 403, the updated average value E _{h + 1}
Using {x} and the allowable value W _{h + 1,} it is determined whether or not the condition of | E _{h + 1} {x} −x _{i + 1} | ≦ W _{h + 1} is satisfied.

In the present embodiment, in the relational expression W = kσ between the allowable value W and the standard deviation σ, the value of k can be continuously changed by the hit count value. For example, when the hit count value is small, k is set to 6, and as the hit count value is increased, the value of k is gradually decreased. When the hit count value exceeds 255, k is kept constant at 3.
This is because it is difficult to determine an appropriate allowable range when the number of parameter samples is small. To solve this, when the hit count value is small, the allowable range is increased as much as possible, and when the hit count value is increased, the allowable range is increased. It is intended to reduce the range to the optimum value W = 3σ.

In this embodiment, as described above, since the allowable range of the parameter is updated every time a pulse is received, even if the external environment changes, the pulse belonging to the specific pulse group can always be accurately classified. . In particular, if the pulse source is moving in position, such as an aircraft, set the parameter to AO.
If A (Angle Of Arrival) is set, the allowable range of AOA changes every moment in response to the movement of the pulse generation source, which is very effective for accurate pulse classification.

Also, even if a pulse is received from a new radio source, an allowable range for this pulse is newly set, and when this pulse is received again, this pulse may be classified based on the newly set allowable range. it can.

Next, a second embodiment of the pulse train classifying apparatus
Explanation will be given based on FIG. 3 and FIG.

As shown in FIG. 2, the pulse train classifier of this embodiment includes a parameter measuring device 3A for measuring two different parameters x and y, and two parameter classifiers (X) 4A and (Y) 4.
B, and a coincidence detection circuit 4C that outputs the cell address of the corresponding pulse group to the processor 5 only when it is determined at the same time that the two input parameters x and y are within the allowable range of the respective parameters. With two parameters
x and y are statistically classified on a two-dimensional plane. Note that the receiver 2, the parameter classifier (X) 4A,
(Y) The configuration of 4B and the processor 5 is the same as that of the first embodiment.

 Next, the operation of the present embodiment will be described.

Since the operation is basically the same as that of the first embodiment, the correction of the average value and the allowable value will be mainly described here with reference to FIG.

Here, three cells A411, B412,
The description will be made by taking the cell B412 as an example among C413.

Tolerance D ₁ which is defined in the cell B412 has a width of ± W _y1 to ± W _x1, y-direction in the x-direction around the point P. P
The point is the average value of each parameter of the pulse group (E ₁ {x}, E
₁ {y}). Now, assuming that a new pulse parameter is input to the Q point on the two-dimensional plane, the Q point is included in the allowable range of the parameter x and the allowable range of the parameter y. Are determined at the same time, and the cell address of the corresponding pulse group is output to the processor 5. afterwards,
As in the first embodiment, the average value and the allowable value are corrected.

The average value is corrected by calculating the coordinate difference between the Q point and the P point in the x direction by Δ
Assuming that the coordinate difference in the x and y directions is Δy, for the parameter x, the coordinate value E ₁ {x} in the x direction of the point P, which is the previous average value of the parameter x, Is added to the coordinate value E ₁ {y} of the point P, which is the average value of the parameter Y, in the y direction. Is performed by adding

Thus, the coordinates of P ′ at the center of the new allowable range are Becomes

To correct the tolerance, the tolerance before correction is set to W _x1 , W _y1, and W
= 3σ, the following equation is calculated for the parameter x, as in the equation (2) shown in the first embodiment. The calculation is performed for the parameter y by the following equation.

By this calculation is performed, the cell B412, the new allowable range D ₂ is set.

The above calculation is performed by the function ROM of the parameter classifier as described in the first embodiment.

As described above, when the pulse is classified using the two parameters, the number of determination conditions increases, and the pulse can be more accurately classified. Although the present embodiment has been described using two parameters, more parameters may be used for more accurate pulse classification.

[Effects of the Invention] According to the present invention, the correction means is provided, so that the allowable range of the parameter is updated every time a pulse is received,
Even if the external environment changes, pulses belonging to a specific pulse group can always be accurately classified.

In addition, even if a pulse from an unknown pulse source is received, the pulse group setting means is provided, so that the allowable range for a new pulse is newly set, and when this pulse is received again, the new range is set. This pulse can be classified based on the tolerance.

[Brief description of the drawings]

FIG. 1 is an overall circuit diagram of a pulse train classifying apparatus according to a first embodiment, and FIGS. 2 and 3 show a second embodiment.
FIG. 2 is an overall circuit diagram of the pulse train classifying device, FIG. 3 is an explanatory diagram for explaining correction of an allowable range, and FIGS.
FIG. 4 is a prior art, FIG. 4 is an overall circuit diagram of a pulse train classifier, and FIG. 5 is an overall circuit diagram of a parameter classifier. 3,3A: Parameter measuring device 4, 4A, 4B: Parameter classifier 4C: Simultaneous coincidence detection circuit, 5: Processor 401: Average value memory, 402: Allowable value memory 403: Parameter judgment circuit 404 … Hit count memory 405 Function ROM, 406 Control circuit 407 Cell address generation circuit

Continuation of the front page (56) References JP-A-2-281177 (JP, A) JP-A-61-280587 (JP, A) JP-A-63-127176 (JP, A) JP-A-63-142282 (JP) JP-A-2-194386 (JP, A) JP-A-3-2685 (JP, A) JP-A-3-111780 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB G01S 7/00-7/42 G01S 13/00-13/95

Claims (3)

(57) [Claims] 1. A parameter measuring means for measuring at least a direction of arrival of a pulse as a parameter of a received pulse, and an allowable range storing means for storing, for one or a plurality of pulse groups, an allowable range of a parameter of the pulse group. Parameter determining means for searching an allowable range including the parameters of the received pulse from the allowable range stored in the allowable range storage means; and the parameter determining means finding an allowable range including the parameters of the received pulse. In this case, a pulse group corresponding to the permissible range is recognized as a pulse group to which the received pulse belongs, and a pulse classifying unit.If the parameter determining unit cannot find a permissible range including a parameter of the received pulse, A new pulse group into which the received pulse is classified is set in the pulse classification unit. And a pulse group setting unit for setting an allowable range of a parameter for the new pulse group in the allowable range storage unit. 2. The pulse train classifying apparatus according to claim 1, wherein said correction means sets an allowable range of a parameter of a pulse group to which said received pulse belongs to an average of the number of pulses and a parameter of a pulse group including said received pulse. A pulse train classifying device for correcting based on a value and a variance. 3. The pulse train classifying apparatus according to claim 1, wherein said correction means is configured to:
A pulse train classification device, wherein the width of the allowable range is reduced.