JP2009038631A - Antenna control apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain an antenna control apparatus compatible with a change, caused by an external factor, in an operating state of an antenna. <P>SOLUTION: An antenna control apparatus includes a gain calculation section 204, a phase difference calculation section 205, an equivalent element position calculation section 207, and a beam/null orientation direction change amount calculation section 208. The gain calculation section 204 calculates a gain after an operating state change, based on an initial value of a gain and information after the operating state change, for each of an in-phase power feeding area 101A and an inverse-phase power feeding area 101B of an array opening. The phase difference calculation section 205 calculates a phase difference between gains in the two areas. The equivalent element position calculation section 207 calculates an equivalent element position after the operating state change based on an initial value of the equivalent element position and information after the operating state change. The beam/null orientation direction change amount calculation section 208 calculates a change amount Δθ of a beam/null orientation direction based on phase difference calculation results and equivalent element position calculation results and feeds it back to an antenna system control section 201. The antenna system control section 201 controls an antenna system 100 so as to correct the change amount of the beam/null orientation direction. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an antenna control apparatus that controls an antenna system that scans the beam / null directivity direction of an electromagnetic wave radiated from a phased array antenna by phase control of an antenna element.

  The conventional apparatus calculates a highly accurate induction signal regardless of the characteristics of the radome by performing boresight error correction due to the influence of the radome in accordance with the beam / null directing direction (see, for example, Patent Document 1). .

JP-A-6-138199

  The amount of change in the beam / null pointing direction due to the influence of the radome depends on the operational state of the antenna system in actual operation. However, the conventional apparatus as described above has a problem that no countermeasure is taken against changes in the operational state of the antenna system in actual operation, such as a change in the operational parameters of the antenna or a failure of the antenna element.

  The present invention has been made to solve the above-described problems, and its purpose is to change the operating state of the antenna system due to external factors such as a change in operating parameters of the antenna system or a stop of the antenna element due to a failure. An antenna control apparatus that can cope with the problem is obtained.

  The antenna control device according to the present invention divides the array opening into two based on the antenna system control unit that instructs the antenna system after the operation state change, the obtained initial value of the gain, and the information after the operation state change. For each of the first and second regions, a gain calculation unit that calculates the gain after the operation state change, and a phase difference that calculates the phase difference between the gains of the first and second regions calculated by the gain calculation unit. Based on the obtained initial value of the equivalent element position and the information after changing the operating state, the equivalent element position calculation for calculating the equivalent element position after changing the operating state for each of the first and second regions. And the phase difference calculation result by the phase difference calculation unit and the equivalent element position calculation result by the equivalent element position calculation unit, A beam / null directivity direction change amount calculation unit that feeds back to the antenna system control unit, and the antenna system control unit determines a desired beam / null directivity direction based on the fed back change amount of the beam / null directivity direction. The antenna system is controlled so as to correct it.

  The antenna control device according to the present invention has an effect of being able to cope with a change in the operating state of the antenna system due to an external factor such as an operation parameter change of the antenna system or a stop of the antenna element due to a failure.

Embodiment 1 FIG.
An antenna control apparatus according to Embodiment 1 of the present invention will be described with reference to FIGS. FIG. 1 is a diagram showing an overview of an antenna system that is a control target of an antenna control apparatus according to Embodiment 1 of the present invention. In the following, in each figure, the same reference numerals indicate the same or corresponding parts.

  In FIG. 1, an antenna system 100 mounted on a ship or the like is provided with a phased array antenna 101 and an external structure 102 that affects the radiation pattern of the antenna such as a radome.

  FIG. 1 shows an outline in the case of directing a beam / null in a certain direction. The array aperture of the phased array antenna 101 is divided into two regions 101A that are fed in the same phase and regions 101B that are fed in the opposite phase. It consists of. An example of operation is as follows. First, an XYZ coordinate system is defined as shown in FIG. 1, and the AZ direction is defined as the Y-axis direction and the EL direction is defined as the X-axis direction. When the array opening is completely point-symmetrical about the origin and the beam / null is directed in the AZ direction, the array opening is divided with the X axis as a boundary, and the in-phase power supply region 101A and the anti-phase power supply region 101B respectively. Stipulate. The relative phase difference between the in-phase power supply region 101A and the reverse-phase power supply region 101B is 180 degrees, and the negative-phase power supply region 101B is fed with a phase difference of 180 degrees with respect to the in-phase power supply region 101A. It shall represent an area.

  FIG. 2 is a block diagram showing the configuration of the antenna control apparatus according to Embodiment 1 of the present invention.

  2, the antenna control device according to Embodiment 1 of the present invention includes an antenna system control unit 201, a gain initial value table calculation unit 202, an external gain initial value / equivalent element position initial value table evaluation device 203, A gain calculation unit 204, a phase difference calculation unit 205, an equivalent element position initial value table calculation unit 206, an equivalent element position calculation unit 207, and a beam / null pointing direction change amount calculation unit 208 are provided.

  Next, the operation of the antenna control apparatus according to the first embodiment will be described with reference to the drawings. FIG. 3 is a diagram showing a concept of an equivalent element position of the antenna system that is a control target of the antenna control apparatus according to Embodiment 1 of the present invention.

  In the antenna system 100 in which the external structure 102 such as a radome is installed, due to the influence of the external structure 102, a certain amount of change of the beam / null occurs between the desired directivity direction and the actual directivity direction. In order to correct the amount of change, it is necessary to define a correction amount according to the actual operating state of the antenna system 100.

  Therefore, the antenna control apparatus according to the first embodiment calculates the amount of change in the beam / null directivity direction caused by the external structure 102 according to the operation status of the antenna system 100 and corrects it at high speed.

  The amount of change in the beam / null directing direction in the antenna control apparatus is calculated by dividing the array aperture of the phased array antenna 101 into two, and calculating the gain phase difference of each region and the position vector of the equivalent element position of each region. To run. Further, when a change in the operation state of the antenna system 100 due to an external factor such as a change in the operation parameter of the antenna system 100 or a stop of the antenna element due to a failure occurs, the gain in the initial state of the antenna system 100 is set as an initial value. Using the operation status of the antenna system 100 during operation as an input parameter, only the difference between the initial value and the contribution of the antenna element in which the change in the operation status has occurred is evaluated, and the amount of change in the beam / null pointing direction is determined. Variable and high-speed calculation according to the operational status of

  First, the antenna system control unit 201 instructs an operation parameter (antenna configuration information) such as an excitation amplitude of an antenna element of the antenna system 100 and receives a state notification from the antenna system 100 to grasp the state of the antenna system 100. As an example of the status notification, there is information such as failure of the antenna element.

  The gain initial value table calculation unit 202 acquires antenna configuration information such as the excitation amplitude of the antenna elements of the antenna system 100 from the antenna system control unit 201 and creates a “gain initial value table” in the initial state of the antenna system 100. To do. The “initial gain value table” can be input from an external device by the external gain initial value / equivalent element position initial value table evaluation device 203.

  The gain calculation unit 204 recalculates only the contribution of the antenna element whose parameter has been changed from the initial gain value based on the “initial gain table” and the antenna configuration information, so that the gain after the operation state change is performed. Calculate The calculation of the gain after the operation state change is performed separately for each of the in-phase power supply region 101A and the negative-phase power supply region 101B as shown in Equation (1) described later.

  The phase difference calculation unit 205 uses the gain calculation result from the gain calculation unit 204 to calculate the phase difference between the gains of the in-phase power supply region 101A and the anti-phase power supply region 101B as shown in Equation (2) described later. To do.

  On the other hand, the equivalent element position initial value table calculation unit 206 creates an “equivalent element position initial value table” in the initial state of the antenna system 100 based on the antenna configuration information.

  The equivalent element position calculation unit 207 recalculates only the contribution of the antenna element whose parameter has been changed based on the “equivalent element position initial value table” and the antenna configuration information. The equivalent element position is calculated as shown in FIG. The “equivalent element position initial value table” can also be obtained from an external device from the external gain initial value / equivalent element position initial value table evaluation apparatus 203 in the same manner as the “gain initial value table”.

  The beam / null pointing direction change amount calculation unit 208 uses the phase difference calculation result from the phase difference calculation unit 205 and the equivalent element position calculation result from the equivalent element position calculation unit 207 to obtain an equation (4) described later. And, as shown in (5), the amount of change in the beam / null pointing direction is calculated. Further, the beam / null directivity direction change amount calculation unit 208 feeds back the obtained change amount of the beam / null directivity direction to the antenna system control unit 201.

  Then, as shown in FIG. 3, the antenna system control unit 201 cancels the amount of change in the fed back beam / null directing direction from the shifted beam / null directing direction (solid line) to a desired beam / null directing direction. The excitation phase of each antenna element is calculated so as to correct in the direction (dotted line), and this is instructed to the antenna system 100 as an operation parameter (antenna configuration information).

  In the first embodiment, calculation of the beam / null pointing direction change amount when the antenna operation state is changed will be described. As an example, a case where N antenna elements are turned off is handled. In addition to turning off the antenna element, the same configuration is used when changing the possible operating state of the antenna, such as changing the excitation amplitude of the antenna element.

  The antenna system control unit 201 instructs the antenna system 100 on information after changing the antenna operation state, such as information on antenna elements to be turned off. Further, similar information is notified to the gain calculation unit 204 and the equivalent element position calculation unit 207.

Based on the information after the antenna operation state change from the antenna system control unit 201, the gain calculation unit 204 changes the operation state for each of the in-phase power supply region 101A and the negative-phase power supply region 101B as shown in the following equation (1). calculating a gain G ^'a post.

Here, G ^a is and gain initial value table calculating unit 202, the initial value of the gain obtained from the outside gain initial value / equivalent element position initial value table evaluating apparatus 203, g _n is the contribution of the gain from the antenna elements Represents. n denotes an antenna element which is OFF, N ^'a represents a number of antenna elements OFF, respectively phase feeding region 101A and the negative phase power supply region 101B. The subscripts i and q mean the in-phase power supply region 101A and the reverse-phase power supply region 101B, respectively.

  Next, the phase difference calculation unit 205 calculates the gain phase difference Δα between the in-phase power supply region 101A and the negative phase power supply region 101B as shown in the following equation (2).

On the other hand, the equivalent element position calculation unit 207 operates based on the antenna configuration information from the antenna system control unit 201 for each of the in-phase power supply region 101A and the negative-phase power supply region 101B as in the following equation (3). calculating the equivalent element position p ^'a _e after the change.

Here, p ^a _e is an initial value of the equivalent element position obtained from the equivalent element position initial value table calculation unit 206 and the external gain initial value / equivalent element position initial value table evaluation apparatus 203, and _pm is each antenna element. Equivalent element position. m is an antenna element which is OFF, N ^'a represents a number of antenna elements OFF, respectively phase feeding region 101A and the negative phase power supply region 101B. The subscripts i and q mean the in-phase power supply region 101A and the reverse-phase power supply region 101B, respectively.

  FIG. 3 shows a conceptual diagram of equivalent element positions. The equivalent element positions 101C and 101D define element positions that transparently represent the contributions of all antenna elements in the in-phase power supply area 101A and the negative-phase power supply area 101B of the phased array antenna 101.

  The beam / null pointing direction change amount calculation unit 208 calculates the change amount of the beam / null pointing direction using the phase difference calculation result and the equivalent element position calculation result as in the following formulas (4) and (5). To do.

Here, r ₁ hat and r ₂ hat indicate unit vectors in a desired null direction and a direction after null shift, respectively. Further, k represents the wave number, and v represents a vector indicating the positional relationship between the equivalent element position vectors in the in-phase power supply region 101A and the reverse-phase power supply region 101B as shown in FIG. First, the null direction vector r ₂ hat after the null shift is calculated so as to satisfy Expression (4). Next, the amount of change Δθ in the beam / null directing direction is calculated from the angular difference between r ₁ hat and r ₂ hat as shown in equation (5).

Embodiment 2. FIG.
An antenna control apparatus according to Embodiment 2 of the present invention will be described.

  Also in the second embodiment, the hardware and software configurations are the same as those of the first embodiment shown in FIGS.

  In the second embodiment, a case corresponding to a change in the operation state of the antenna system 100 due to an external factor such as an antenna element being stopped due to a failure is handled. As an example, consider a case where some N antenna elements fail.

  The antenna system control unit 201 receives the failed antenna element information from the antenna system 100 and notifies the gain calculation unit 204 and the equivalent element position calculation unit 207 of the information.

  The processing after the gain calculation unit 204 is exactly the same as in the first embodiment. However, n in the formula (1) and m in the formula (3) each represent a failed antenna element.

Embodiment 3 FIG.
An antenna control apparatus according to Embodiment 3 of the present invention will be described.

  Also in the third embodiment, the hardware and software configurations are the same as those of the first embodiment shown in FIGS.

  In the third embodiment, the operating state of the antenna system 100 is changed due to external factors such as a change in the antenna position with respect to the external structure 102, a change in electrical characteristics of the external structure 102, and a change in the position of the external structure 102. This is a case where the operation state that occurs and the change affects all antenna elements changes, that is, the initial state of the antenna system 100 changes.

  The antenna system control unit 201 receives the information after the change of the operation state from the antenna system 100 and notifies the gain initial value table calculation unit 202 and the equivalent element position initial value table calculation unit 206 of the information. The gain initial value table calculation unit 202 and the equivalent element position initial value table calculation unit 206 recalculate the “gain initial value table” and the “equivalent element position initial value table”, respectively, and execute initialization of the tables.

  The gain initial value table calculation unit 202 sends the “gain initial value table” to the gain calculation unit 204, and the equivalent element position initial value table calculation unit 206 sends the “equivalent element position initial value table” to the equivalent element position calculation unit 207, respectively. Notice.

  The processing after the gain calculation unit 204 is the same processing as in the first embodiment. However, when there is no change in the operating state of the antenna element, n = m = 0 in the equations (1) and (3).

It is a figure which shows the general view of the antenna system which is a control object of the antenna control apparatus which concerns on Embodiment 1 of this invention. It is a block diagram which shows the structure of the antenna control apparatus which concerns on Embodiment 1 of this invention. It is a figure which shows the concept of the equivalent element position of the antenna system which is a control object of the antenna control apparatus which concerns on Embodiment 1 of this invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 100 antenna system, 101 phased array antenna, 101A in-phase feeding area, 101B reverse phase feeding area, 102 external structure, 201 antenna system control part, 202 gain initial value table calculation part, 203 equivalent element position initial value table evaluation apparatus, 204 Gain calculation unit, 205 phase difference calculation unit, 206 equivalent element position initial value table calculation unit, 207 equivalent element position calculation unit, 208 beam / null pointing direction change amount calculation unit.

Claims (5)

An antenna system control unit for instructing the antenna system of information after the operation state change;
Based on the obtained initial value of the gain and the information after the operation state change, a gain calculation unit for calculating the gain after the operation state change for each of the first and second regions into which the array opening is divided into two;
A phase difference calculator for calculating a phase difference between the gains of the first and second regions calculated by the gain calculator;
Based on the obtained initial value of the equivalent element position and the information after the operation state change, for each of the first and second regions, an equivalent element position calculation unit that calculates the equivalent element position after the operation state change;
Based on the phase difference calculation result by the phase difference calculation unit and the equivalent element position calculation result by the equivalent element position calculation unit, the beam / null pointing direction change amount is calculated and fed back to the antenna system control unit. A null-oriented direction change amount calculation unit,
The antenna system control unit controls the antenna system so as to correct in a desired beam / null directivity direction based on a fed back beam / null directivity change amount. The first and second regions are respectively an in-phase power feeding region fed in the same phase and a reverse phase feeding region fed in the opposite phase, and a relative phase difference between the in-phase feeding region and the opposite phase feeding region is 180 degrees. The antenna control device according to claim 1, wherein: When turning off a predetermined number of antenna elements as an operational status change of the antenna system,
The antenna system control unit notifies the gain calculation unit and the equivalent element position calculation unit of the information after the operation state change,
The gain calculation unit calculates a gain after changing the operation state for each of the first and second regions by subtracting a total gain value of a predetermined number of antenna elements to be turned off from an initial gain value. ,
The equivalent element position calculation unit subtracts the total value of the element positions of a predetermined number of antenna elements to be turned off from the initial value of the equivalent element position, so that the first and second regions are respectively The antenna control device according to claim 2, wherein the equivalent element position after the operation state change is calculated for each of the second regions. When a predetermined number of antenna elements break down as a change in the operating status of the antenna system,
The antenna system control unit, instead of instructing the antenna system information after the operation state change, receives the information after the operation state change from the antenna system and notifies the gain calculation unit and the equivalent element position calculation unit,
The gain calculation unit calculates a gain after changing the operation state for each of the first and second regions by subtracting a total gain value of a predetermined number of failed antenna elements from an initial gain value. ,
The equivalent element position calculation unit subtracts the total value of the element positions of the predetermined number of failed antenna elements from the initial value of the equivalent element position, so that the first and second regions are respectively The antenna control device according to claim 2, wherein the equivalent element position after the operation state change is calculated for each of the second regions. A gain initial value table calculation unit that acquires antenna configuration information and creates a gain initial value table in an initial state of the antenna system;
An equivalent element position initial value table calculating unit that obtains antenna configuration information and creates an equivalent element position initial value table in an initial state of the antenna system; and
When the operational status of the antenna system changes due to external factors, and the operational status changes that affect all antenna elements,
The antenna system control unit receives the information after the change of the operation state from the antenna system, and notifies the initial gain value table calculation unit and the equivalent element position initial value table calculation unit,
The initial gain value table calculation unit recalculates the initial gain value table based on the information after the change of the operation state, performs initialization of the table, and sets the initial value of the gain after the change of the operation state as the gain Notify the calculation department,
The equivalent element position initial value table calculation unit recalculates the equivalent element position initial value table based on the information after the change in the operation state, executes initialization of the table, and the equivalent element position after the change in the operation state The antenna control apparatus according to claim 2, wherein the equivalent element position calculation unit is notified of the initial value of.

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