KR101544820B1 - Calibration method of monopulse radar system - Google Patents

Abstract

A reception channel calibration method for a monopulse radar system is disclosed. The reception channel calibration method for a monopulse radar system applies a reception calibration signal generated by a transmission unit in a calibration mode to a side after a monopulse distributor to calculate a calibration value for phase and amplitude distortion of a sum and a difference channel of a reception signal which can be generated on the side after the monopulse distributor, and then applies the reception calibration signal again to a side before the monopulse distributor to calculate a calibration value for phase and amplitude distortion of a reception signal which can be generated on the side before the monopulse distributor to accurately calibrate the sides before and after the monopulse distributor in a probing mode. Therefore, a target can be accurately detected.

Description

[0001] CALIBRATION METHOD OF MONOPULSE RADAR SYSTEM [0002]

The present invention relates to a receiving channel correction method for a radar system, and more particularly to a receiving channel correction method for a monopulse radar system.

A monopulse radar is a type of tracking radar that is designed to track a target by measuring a received signal reflected from a target by emitting a single pulse of the transmitted signal in the direction of a specified target. The monopulse radar transmits and receives a single signal, ), Azimuth (azimuth), and elevation (Elevation) at the same time.

The monopulse radar receives the received signal through each of the plurality of receive channels and acquires the azimuth, elevation, and distance information of the target using the difference between the received signals received at each of the plurality of receive channels. That is, when the target is positioned at the center of the transmitted transmission signal, the intensity of the received signal entering each of the plurality of reception channels is the same. However, if the target deviates from the center of the transmitted transmission signal, The strengths of the received signals appear different from each other. The monopulse radar is configured to track the target using a change in the received signal for each of the receiving channels.

Monopulse radar has the advantage that it can detect and display all the azimuth, elevation and distance information about the target by one beam transmission and reception, but it can not obtain the accurate detection information about the target due to deterioration of performance due to various factors There is a disadvantage that the case can occur. In particular, changes in the phase and amplitude of the signal occur due to environmental factors such as time and ambient temperature. Therefore, monopulse radar requires regular or irregular corrections to the detection performance.

Fig. 1 shows an example of an antenna substructure of a general monopulse radar system.

FIG. 1 shows an example of an antenna unit ANT of a monopulse radar system generally used to improve understanding of the configuration of the monopulse radar system of the present invention. The antenna unit ANT of a monopulse radar system having four reception channels ). The antenna unit ANT has four horn antennas H1 to H4 corresponding to four reception channels, each of which is implemented as a feed horn. Each of the four horn antennas H1 to H4 has the same size and shape, and is arranged by evenly dividing the antenna section ANT into four quadrants.

Each of the four horn antennas H1 to H4 radiates the transmission signals applied from the transmitter of the monopulse radar system in the same phase and size and outputs the reception signals A to D individually reflected by the target . The four horn antennas H1 to H4 that respectively receive the received signals A to D transmit the received signals A to D to the corresponding ones of the plurality of corresponding reception channels and the monopulse radar system 4 The sum and difference of the reception signals A to D for each reception channel are calculated for the monopulse processing of the reception signals A to D transmitted through the respective reception channels. And acquires the elevation angle and azimuth information of the target using the sum and difference of the calculated reception signals A to D for each channel. This is because when the reception signal is received through the four horn antennas H1 to H4, a difference occurs in the phase and amplitude of the reception signal applied through each antenna due to the positional difference of the four horn antennas H1 to H4 Because.

That is, the monopulse radar system radiates one transmission signal, receives a reception signal of which one transmission signal is reflected by a target through a plurality of horn antennas H1 to H4, and a plurality of horn antennas H1 to H4, The difference between the phase and the amplitude of the reception signal for each reception channel generated according to the position of the reception channel is calculated to obtain the high angle and azimuth information for the target.

For example, the monopulse radar system calculates the sum signal of the received signals A to D as Σ = (A + B + C + D) and determines the azimuth of the target according to the arrangement of the horn antennas H1 to H4 (A + D) - (B + C) to calculate the azimuth difference signal to calculate the azimuth difference signal as ΔAZ = (A + B) - (C + D) and to determine the elevation angle. The azimuth angle and the elevation angle of the target are calculated using the ratio ΔAZ / Σ between the calculated azimuth difference signal ΔAZ and the sum signal Σ and the ratio ΔEL / Σ between the high angle difference signal ΔEL and the sum signal Σ. .

The calculation method of the azimuth difference signal ΔAZ and the high angle difference signal ΔEL is determined by the arrangement of the horn antennas H1 to H4 shown in FIG. That is, the monopulse radar system is configured to receive signals A and B received through the horn antennas H1 and H2 disposed on the right side of the horn antennas H1 through H4 and horn antennas H3 and H4 disposed on the left side, Calculate the difference between the received signals (C, D) to determine the azimuth of the target. The reception signals A and D received through the horn antennas H1 and H4 disposed at the upper end of the four horn antennas H1 through H4 and the reception signals A and D received through the horn antennas H2 and H3 disposed at the lower end Calculate the difference between the signals (B, C) to determine the elevation of the target.

However, in order to accurately determine the position of the target by using the above-described monopulse radar sum signal Σ, azimuth difference signal ΔAZ and high angle difference signal ΔEL, The error between the two should be corrected. That is, when the same signal is applied to the four horn antennas H1 to H4, the difference signals? AZ and? EL should be calculated as zero. However, when an actual monopulse radar system is constructed, it is very difficult to configure the plurality of reception channels to have the same physical characteristics. Therefore, in the conventional monopulse radar system, the accuracy of the monopulse radar is improved by measuring the characteristics of a plurality of reception channels in advance and applying a correction value.

2 shows a configuration of a conventional monopulse radar system.

Referring to FIG. 2, a conventional monopulse radar system 10 includes a transmitter 11 for generating a transmission signal, a receiver for analyzing a reception signal reflected from the target and receiving the transmission signal, And an antenna unit (ANT) for radiating a transmission signal and receiving a reception signal.

2, the receiving unit 12 includes n receiving channels (n is a natural number of 2 or more) and includes a plurality of receiving shearing units PEP1 to PEPn corresponding to n receiving channels. Each of the plurality of receiving shearing units PEP1 to PEPn performs an operation of correcting an error of a receiving signal applied to a corresponding receiving channel by a receiving channel.

As shown in FIG. 2, various methods have been proposed to correct the distortion of the received signal even in a conventional monopulse radar. However, in the monopulse radar structure, basically, only the correction Respectively. Similarly, Korean Patent No. 10-1201901 (Nov. 9, 2012) discloses a technique for reducing an error of a reception signal caused by a difference in length between reception channels.

However, the conventional monopulse radar does not perform any correction when the received signal output from the mono pulse distributor is distorted. That is, it is assumed that the distortion of the received signal occurring after the mono pulse distributor does not occur, and is ignored. However, distortion actually occurs in the received signal after the mono pulse distributor. Although the error of the detection performance of the target is not so great, there is a problem in that it is not suitable for a recent radar system requiring more accurate accuracy.

It is an object of the present invention to provide a method for correcting a reception channel of a monopulse radar system having a high accuracy by correcting distortion of a received signal transmitted after a mono pulse distributor as well as distortion of a received signal before a mono pulse divider in a receiving channel have.

According to an aspect of the present invention, there is provided a receiving channel correction method for a monopulse radar system, including an antenna unit including a plurality of antennas, a transmitter, a transmission amplifier, a correction signal coupler, a switch, And a receiving unit including a plurality of couplers, a receiving front end, a mono pulse distributor, a correction signal distributor, a receiving end and a signal processor, the receiving channel correcting method of the monopulse radar system comprising: Receiving a reception correction signal by the reception end, and obtaining a reference channel signal, a sum channel signal, and first and second differential channel signals, and the signal processor obtains the sum channel signal and the first and second channel signals And corrects an error occurring in the sum channel signal and the first and second channel signals by comparing the reference channel signal with the reference channel signal Rear end correction method comprising: obtaining a channel correction value; And a receiver for receiving the sum channel signal and the first and second differential channel signals using the reception correction signal applied to the reception front end, A front end correction step of obtaining a reception correction value for correcting an error; .

Wherein the post-stage correction step comprises: the signal processor entering a post-stage correction mode; The transmitter generating the reception correction signal under the control of the signal processor; Coupling the correction correction signal to the correction signal coupler and applying the correction signal to the reference reception rear end of the reception end to obtain the reference channel signal; Dividing the reception correction signal applied from the switch, and transmitting the divided signals to the correction signal distributor in a short period after the summing reception at the rear end of the reception and at a short period after the first and second reception; Receiving the sum channel signal and the first and second difference channel signals from the reception correction signal after the sum reception and the short term and after the first and second reception, respectively; And the signal processor compares the sum channel signal with the first and second difference channel signals to obtain a sum channel correction value and a first and a second difference correction value as a channel correction value; And a control unit.

Wherein the step of correcting the front end comprises: entering the front end correction mode by the signal processor; The transmitter generating the receive correction signal; Coupling the correction correction signal to the reference signal reception end to obtain the reference channel signal; Dividing the reception correction signal applied from the switch and transmitting the divided signals to each of a plurality of reception shear units of the reception front end through the plurality of couplers; One of the plurality of reception shear stages, which is turned on in accordance with the control of the signal processor, transmits the reception correction signal to the mono pulse distributor; Receiving the reception correction signal from the reception front end of the plurality of reception front end units, and generating a sum signal, an azimuth difference signal, and a high-angle difference signal using the reception correction signal; Acquiring the sum channel signal and the first and second difference channel signals from the sum signal, the azimuth difference signal, and the high angle difference signal, respectively; Wherein the signal processor obtains a correction value by comparing the sum channel signal and the first and second difference channel signals with the reference channel signal and calculates a correction value based on the sum channel correction value and the first and second Obtaining the reception correction value corresponding to the reception preamble in the ON state by subtracting the correction value; And judging whether or not the reception correction value corresponding to each of the plurality of reception shears is acquired and if it is determined that the reception correction value corresponding to each of the plurality of reception shears is not acquired, Sequentially turning on the reception shear stage in which the reception correction value is not obtained to acquire the reception correction value; And a control unit.

Wherein the step of correcting the front end comprises: applying the sum channel correction value and the first and second difference correction values obtained at the rear end searching step to the short term after the sum reception and the short term after the first and second reception; And applying the obtained plurality of reception correction values to each of the plurality of reception shear units of the plurality of reception shear units. And further comprising:

A receiving channel correcting method of the monopulse radar system includes a transmitting step of radiating a transmission signal generated in the transmitter through the plurality of antennas of the antenna unit; And a receiver for receiving the plurality of received signals reflected on the target and received by the plurality of antennas, respectively, and obtaining the sum channel signal and the first and second differential channel signals from the plurality of received signals, A receiving step of determining a position; And further comprising:

Wherein the transmitting step comprises: the transmitter generating the transmission signal; Dividing a transmission signal generated by the transmitter into a plurality of signals by the first N distributor; Amplifying the plurality of transmission signals distributed by the first N divider by the transmission amplifier; And radiating the amplified transmission signals through a corresponding one of the plurality of antennas of the antenna unit; .

Wherein each of the plurality of reception shears receives a reception signal through a corresponding antenna among the plurality of antennas and corrects the reception signal in response to a corresponding reception correction value among the plurality of reception correction values, To a mono pulse distributor; The monopulse distributor generates the sum signal and the first and second difference signals using the reception signals applied to the plurality of reception shear devices, and outputs the sum signal and the first and second difference signals, Respectively; The sum signal and the first and second difference signals are respectively applied to the sum signal and the first and second difference signals to convert the sum signal and the first and second difference signals in a predetermined manner, Correcting the sum channel signal and the first and second difference channel signals obtained using the sum channel correction value and the first and second difference correction values; And the signal processor receives and analyzes the sum channel correction value and the first and second difference correction values from the short term after the sum reception and the short term after the first and second reception to determine the position of the target ; And a control unit.

Therefore, in the reception channel correction method of the monopulse radar system of the present invention, the sum of the reception signals that may occur at the end of the mono pulse distributor and the correction value for the phase and amplitude distortion of the difference channel are calculated first, It is possible to compensate both of the errors before and after the mono pulse distributor by making it possible to be reflected together with the reception channel correction of the previous stage of the mono pulse distributor. Thus, target information having a precise azimuth angle and high angle accuracy can be provided.

Fig. 1 shows an example of an antenna substructure of a general monopulse radar system.
2 shows a configuration of a conventional monopulse radar system.
3 shows a configuration of a monopulse radar system according to an embodiment of the present invention.
FIG. 4 illustrates a receive channel correction method of a monopulse radar system according to an embodiment of the present invention.
FIG. 5 is a detailed view illustrating a sum channel and a difference correction value acquisition step of FIG.
FIG. 6 is a detailed view of the reception correction value acquisition step of FIG.

In order to fully understand the present invention, operational advantages of the present invention, and objects achieved by the practice of the present invention, reference should be made to the accompanying drawings and the accompanying drawings which illustrate preferred embodiments of the present invention.

Hereinafter, the present invention will be described in detail with reference to the preferred embodiments of the present invention with reference to the accompanying drawings. However, the present invention can be implemented in various different forms, and is not limited to the embodiments described. In order to clearly describe the present invention, parts that are not related to the description are omitted, and the same reference numerals in the drawings denote the same members.

Throughout the specification, when an element is referred to as "including" an element, it does not exclude other elements unless specifically stated to the contrary. The terms "part", "unit", "module", "block", and the like described in the specification mean units for processing at least one function or operation, And a combination of software.

3 shows a configuration of a monopulse radar system according to an embodiment of the present invention.

The monopulse radar system 100 of FIG. 3 is similar to the monopulse radar system of FIG. 2 except that it includes a transmitter 110 for generating a transmission signal and a transmitter 110 for radiating a transmission signal, And a receiving unit 120 for analyzing the received signal and the received signal to determine the position and distance of the target.

The transmission section 11 includes a transmitter Syth, a transmission amplifier TR, a correction signal coupler CPr, a switch SW and N distributors DV1 and DV2.

The transmitter Syth generates a transmission signal of a predetermined pulse waveform or a reception correction signal rcs. The transmitter Syth generates the transmission signal ts in the search mode in which the monopulse radar system 100 searches for the target and the correction mode in which the monopulse radar system 100 corrects the channel- A reception correction signal rcs is generated. Here, the transmission signal ts and the reception correction signal rcs are signals classified according to the operation mode of the monopulse radar system 100 and may be generated as signals different from each other. However, in order to improve the accuracy of error correction for each reception channel It is preferable to generate the same signal. The transmitter Syth can generate the transmission signal ts or the reception correction signal rcs under the control of the signal processor RV of the receiver 120. [

The N divider DV1 and the transmission amplifier TR operate in the search mode and the N divider DV1 receives the transmission signal ts from the transmitter Syth and distributes the transmission signal ts in the number corresponding to the number of antennas, (TR). The transmission amplification unit TR receives the transmission signal ts divided by the N divider DV1 and amplifies the applied transmission signal ts and outputs the amplified transmission signal ts to the plurality of circulators CR1 to CRn of the reception unit 120 To the corresponding circulator. The plurality of circulators CR1 to CRn switch the signal transmission paths at the time of signal transmission in the search mode so that each of the plurality of amplified transmission signals ts applied from the transmission amplifier TR is transmitted to the plurality of horn antennas H1 to Hn, Through the corresponding horn antenna.

The correction signal coupler CPr, the switch SW and the N-divider DV2 are configured to operate in the correction mode.

First, the correction signal coupler CPr receives the reception correction signal rcs generated by the transmitter Syth in the correction mode, and transmits the reception correction signal rcs to the reference reception short term (POPR) of the reception unit 120. [

The switch SW receives the reception correction signal rcs and selectively transmits it to the N distributor DV2 or the correction signal distributor DV3 of the receiver 120. [ At this time, the switch SW may also perform the switching operation under the control of the signal processor (RV). The switch SW transmits the applied reception correction signal rcs to the correction signal distributor DV3 when the monopulse radar system 100 is in the rear stage correction mode for correcting the signal error in the short period after reception in the correction mode And transmits the received reception correction signal rcs to the N-distributor DV2 in the case of the front end correction mode for correcting the signal error of the reception shear period.

Here, the switch SW is arranged so as to prevent the reception correction signal rcs from leaking through the N divider DV2 in the rear stage correction mode and being superimposed on the reception short-circuit PEP1 to PEPn over a short period , The isolation between output terminals should be designed to be sufficiently high.

N divider DV2 divides the reception correction signal rcs applied through the switch SW into a number corresponding to the number of reception channels of the reception unit 120, that is, the number of antennas, (CP1 to CPn).

The antenna unit may be implemented by a plurality of horn antennas H1 to Hn. Each of the plurality of horn antennas H1 to Hn emits a transmission signal applied through a corresponding one of the plurality of couplers CP1 to CPn, And transmits the received signal whose reflected radiated transmission signal is reflected to the target to the corresponding one of the plurality of circulators CR1 to CRn. In the above description, the antenna unit emits a transmission signal. However, in some cases, a separate transmission antenna for radiating a transmission signal may be further provided. In this case, the plurality of circulators CR1 to CRn of the receiving unit 120 may be omitted.

Although FIG. 1 shows an antenna unit having four horn antennas H1 to H4 implemented as a feed horn, the number and arrangement of the horn antennas can be variously adjusted according to the monopulse radar system. In some cases, But may be implemented by other types of antennas other than the horn antennas implemented by the feed horn.

The receiving unit 120 includes a receiving front end having a plurality of couplers CP1 to CPn and a plurality of circulators CR1 to CRn and a plurality of receiving shearing units PEP1 to PEPn, a mono pulse distributor (DVM) (DV3), a receiving end and a signal processor (RV) having four receiving terminals (POPR, POPS, POPD1, POPD2).

The plurality of couplers CP1 to CPn and the plurality of reception shear units PEP1 to PEPn are provided in the number corresponding to the number of reception channels n (where n is a natural number of 2 or more). Each of the plurality of couplers CP1 to CPn couples the reception correction signal rcs applied from the N divider DV2 of the transmission unit 110. [

The plurality of circulators CR1 to CRn switch the signal transmission paths at the time of signal transmission in the search mode so that each of the plurality of amplified transmission signals ts applied from the transmission amplifier TR is transmitted to the plurality of horn antennas H1 to Hn, The reception signal received via the corresponding horn antenna among the plurality of horn antennas H1 to Hn is received by the corresponding one of the plurality of reception shears PEP1 to PEPn The signal transmission path is switched so that it is transmitted to the shear period. The plurality of circulators CR1 to CRn may be configured such that the reception correction signal rcs applied from the plurality of couplers CP1 to CPn in the front end correction mode during the correction mode is received by a corresponding one of the plurality of reception shears PEP1 to PEPn The signal transmission path is switched so that it is transmitted to the shear period. In the case of the rear end correction mode, the reception correction signal rcs is not applied to the plurality of reception shearing devices PEP1 to PEPn. The plurality of circulators CR1 to CRn can switch signal transmission paths under the control of the signal processor RV.

The plurality of receiving shear units PEP1 to PEPn are arranged to receive signals received from the corresponding circulators of the plurality of circulators CR1 to CRn in the receiving mode during the search mode according to the reception correction value supplied from the signal processor RV And transmits it to the mono pulse distributor (DVM). In other words, each of the plurality of receiving shearing devices PEP1 to PEPn compensates for phase and amplitude errors caused by differences in the paths of the received signals received through the plurality of horn antennas H1 to Hn.

Each of the plurality of receiving shearing machines PEP1 to PEPn is sequentially turned on in the front end correction mode and receives the reception correction signal rcs through a corresponding one of the plurality of couplers CP1 to CPn, (DVM). The reason that the plurality of receiving shearing devices PEP1 to PEPn are sequentially turned on in the front end correction mode is to individually acquire the correction values for the plurality of receiving shearing devices PEP1 to PEPn. When the monopulse radar system 100 is in the rear end correction mode, since the reception correction signal rcs is not applied by the switch SW and the plurality of circulators CR1 to CRn, the plurality of reception shear units PEP1 to PEPn May be turned on, but is preferably turned off to prevent the introduction of noise.

Here, the on / off state switching of each of the plurality of receiving shears PEP1 to PEPn may be performed under the control of the signal processor RV.

The monopulse distributor DVM generates the sum signal Σ of the reception signals applied through the plurality of reception shear devices PEP1 to PEPn, the azimuth difference signal ΔAZ and the high angle difference signal ΔEL, (POPS), and transmits the difference signals (? AZ,? EL) to the first and second receiving and post-periods (POPD1, POPD2). The monopulse divider (DVM) combines the reception signals applied from the plurality of reception shear units PEP1 to PEPn as shown in FIG. 1 to generate a sum signal (?), And outputs the sum signal (?) Symmetrically arranged in the vertical direction H1 to Hn by 180 degrees to generate an azimuth difference signal ΔAZ and the phase of the received signals received from the horn antennas H1 to Hn symmetrically arranged in the horizontal direction is 180 And also generates a high angle difference signal? EL.

The correction signal distributor DV3 receives and distributes the reception correction signal rcs from the switch SW in the rear end correction mode during the correction mode and outputs the reception correction signal rcs to the first and second reception end points POPD1 , And POPD2, respectively.

(POPS) and the first and second differential reception short periods (POPD1 and POPD2) are respectively supplied from the monopulse distributor (DVM) in the search mode or the front end correction mode, The azimuth difference signal ΔAZ and the high angle difference signal ΔEL to perform a predetermined operation such as noise elimination, amplification and band filtering to obtain the sum channel signal chS and the first and second differential channel signals chD1 and transmits the obtained sum channel signal chS and the difference channel signals chD1 and chD2 to the signal processor RV. (POPS) and the first and second differential reception short periods (POPD1 and POPD2) in the search mode are respectively calculated by the signal processor (RV) and the sum channel correction values calculated in the signal processor (RV) (CHS) and the first and second differential channel signals (chD1 and chD2) in response to the value of the sum signal.

In the rear end correction mode, the reception correction signal rcs applied from the correction signal distributor DV3 is applied according to the control of the signal processor RV, and the sum channel signal chS and the first and second differential channel signals chD1, chD2). At this time, the signal processor (RV) receives the sum channel correction value and the first and second channel correction values, respectively, in the short term (POPS) and the short term (POPD) And transmits the signal chS and the first and second differential channel signals chD1 and chD2 to the signal processor RV.

(POPR) receives the reception correction signal rcs applied from the correction signal coupler CPr of the transmission unit 110 in the front end correction mode or the rear end correction mode, (POPD1, POPD2) and transmits the reference channel signal chR to the signal processor RV. However, in the search mode, it is kept in the OFF state under the control of the signal processor (RV). In this case, the sum of the sum signal (Σ), azimuth difference signal (ΔAZ), and high angle difference (Σ) applied to the short term (POPS) and the short term (POPD) Performing the same operation as that of the signal? EL is performed when the signal processor RV multiplies the reference channel signal chR obtained corresponding to the reception correction signal rcs by the sum signal?, The azimuth difference signal? The sum channel signal chS and the difference channel signals chD1 and chD2 obtained in correspondence to the difference signal DELTA EL can be easily compared with each other.

The signal processor RV first operates in the correction mode and controls the transmitter Syth of the transmission unit 110 in the rear end correction mode during the correction mode to generate the reception correction signal rcs. Then, the switch SW is controlled so that the reception correction signal rcs is applied to the correction signal distributor DV3. The correction signal distributor DV3 distributes the reception correction signal rcs applied from the switch SW and applies it to the short term POPS and the first and second short term reception POPD1 and POPD2 respectively. On the other hand, the generated reception correction signal rcs is coupled to the correction signal coupler CPr and transmitted to the POPR after receiving the reference signal.

Therefore, the reference channel signal (chR) for the reception correction signal (rcs) is generated in the short term post-period (POPR) in the rear stage correction mode, and the reference channel signal (chR) is generated in the short term (POPS) The first and second channel signals chD1 and chD2 for the reception correction signal rcs other than the sum signal Σ, the azimuth difference signal ΔAZ and the high angle difference signal ΔEL, chD2) and transmits it to the signal processor (RV). The signal processor RV receives the sum channel signal chS and the first and second channel signals chD1 and chD2 on the basis of the reference channel signal chR applied corresponding to the same reception correction signal rcs. Phase and amplitude error are analyzed. A sum channel correction value and a first and second difference correction values for correcting phase and amplitude errors of the analyzed sum channel signal chS and the first and second differential channel signals chD1 and chD2 are generated . Here, the sum channel correction value is a correction value for correcting the phase and amplitude error of the sum channel signal chS by the short term POPS after reception of the sum, and the first channel correction value is the short term POPD1 after the first reception, And the second-order channel correction value is a correction value for correcting the phase and amplitude error of the second-order channel signal chD2 due to the second- It is a correction value for correcting the phase and amplitude error. Then, the sum channel correction value is applied to the short term (POPS) after the sum reception, and the sum channel signal (chS) obtained in the short term (POPS) in the search mode can be corrected. Likewise, the generated first and second differential channel correction values are applied to the first and second differential reception short periods POPD1 and POPD2 to determine whether the first and second differential reception short periods POPD1 and POPD2 are acquired So that the first and second channel signals chD1 and chD2 can be corrected.

Then, the signal processor RV operates in the front end correction mode during the correction mode. In the front end correction mode, the signal processor RV controls the transmitter Syth like the rear end correction mode to generate the reception correction signal rcs. However, the signal processor RV controls the switch SW to transmit the reception correction signal rcs to the N-divider DV2 in the front end correction mode. The reception correction signal rcs is applied to the N divider DV2 and distributed to the plurality of couplers CP1 to CPn.

On the other hand, the signal processor RV sequentially turns on one of the plurality of receiving shearing machines PEP1 to PEPn in the front end correction mode. Accordingly, one of the plurality of receiving shearing devices PEP1 to PEPn, which is on-state, transmits the receiving signal to the monopulse distributor (DVM), and the other receiving shearing device does not transmit the signal. Therefore, the monopulse distributor DVM generates sum signal Σ, azimuth difference signal ΔAZ and high angle difference signal ΔEL from a single received signal and outputs them to the short term chS, After the second reception, it is transmitted in the short term (chD1, chD2).

(POPS) and the first and second differential reception short periods (POPD1 and POPD2) receive the sum signal (?), The azimuth difference signal (? AZ) and the high angle difference signal (? EL) and transmits the first and second channel signals chD1 and chD2 to the signal processor RV. The reference receiving and post-termination period (POPR) receives the reception correction signal rcs from the correction signal coupler CPr and transmits the reference channel signal chR to the signal processor RV.

The signal processor RV receives and compares the reference channel signal chR with the sum channel signal chS and the first and second differential channel signals chD1 and chD2 to generate a sum channel signal for the reference channel signal chR, (chS) and the first and second differential channel signals (chD1, chD2), and obtains a correction value from the calculated relative phase and amplitude. By subtracting the sum channel correction value and the first and second channel correction values calculated in the post-stage correction mode from the correction value, the phase and amplitude error of the channel generated in the reception shear stage are calculated, and the received shear stages PEP1 to PEPn Lt; / RTI >

When all of the reception correction values for the plurality of receiving shear units PEP1 to PEPn are obtained, the signal processor RV compares the reception correction value for each of the obtained plurality of receiving shear units PEP1 to PEPn, Value and the first and second channel correction values to a plurality of receiving shear units PEP1 to PEPn and a summing and receiving unit POPS and first and second differential receiving short units POPD1 and POPD2.

(POPS) and the first and second differential reception short-periods (POPD1 and POPD2) receive the sum signal (?) And the azimuth difference signal (?) According to the applied sum channel correction value and the first and second- And the phase and amplitude to correct the high-angle difference signal DELTA EL and the high-angle difference signal DELTA EL. The plurality of receiving shearing devices PEP1 to PEPn also set the phase and amplitude to correct the received signal according to the applied reception correction value, respectively. (PEP1 to PEPn), the sum of the reception short-term (POPS), and the short-term (POPD1, POPD2) of the first and second reception.

The signal processor (RV) switches to the search mode after the correction mode is completed. In the transmission mode during the search mode, the signal processor RV controls the transmitter Syth to generate the transmission signal ts. Then, the switch SW selects and applies the transmit signal to the N-divider DV2. The transmission signal applied to the N divider DV2 is distributed and applied to a plurality of couplers CP1 to CPn of the receiving unit 120 and radiated through a plurality of horn antennas H1 to Hn of the antenna unit. At this time, the signal processor RV controls the reference reception short period POPR to the OFF state, and the short period POPS and the first and second differential reception short periods POPD1 and POPD2 are controlled by the correction signal distributor DV3, (DVM), rather than a mono pulse distributor (DVM).

The signal processor (RV) switches from the transmission mode to the reception mode when the transmission signal is radiated to the antenna. In the receiving mode, the plurality of receiving shearing devices PEP1 to PEPn receive the reflected waves of the radiated transmitted signals as targets, through the plurality of horn antennas H1 to Hn, And corrects the error according to the path difference for each receiving channel, and transmits it to the mono pulse distributor (DVM). The monopulse divider (DVM) generates a sum signal (?), An azimuth difference signal (? AZ) and a high-angle difference signal (? EL) by receiving a plurality of reception signals whose errors are corrected, 1 and the second-order reception short-term period (POPD1, POPD2), respectively. (POPS) and the first and second reception short periods (POPD1 and POPD2) receive the azimuth difference signal (? AZ) and the high angle difference signal (? EL) And the first and second differential channel signals chD1 and chD2. In this case, the POPS and the first and second reception short-term ends (POPD1 and POPD2) of the sum-receiving and receiving-end signals are generated according to the sum channel correction value and the difference value of the channel applied in the signal processor (RV) And applies the corrected sum channel signal chS and the first and second differential channel signals chD1 and chD2 to the signal processor RV.

The signal processor RV receives and analyzes the corrected sum channel signal chS and the first and second differential channel signals chD1 and chD2 to discriminate the distance, the azimuth angle, and the elevation angle of the target. The direction of the plurality of horn antennas can be controlled according to the determined distance, azimuth angle, and elevation angle to control the tracking of the target.

As described above, in the monopulse radar system, the phase and amplitude of the signal may change due to factors of the surrounding environment such as time and ambient temperature. Therefore, when the correction command is applied at a predetermined period or externally, (POPS), and the first and second reception short periods (POPD1 and POPD2) after entering the first and second reception modes (PEP1 to PEPn).

Therefore, the monopulse radar system of the present invention is different from the monopulse radar system in that the existing monopulse radar system only performs correction for the reception shear stages (PEP1 to PEPn) It is possible to further correct the short term (POPD1, POPD2), so that more accurate detection performance can be provided.

In addition, since the transmitter of the transmitter 110 is also configured as an active element, the phase and amplitude of the reception correction signal rcs due to the surrounding environment such as time and temperature may occur. However, since the reception correction signal rcs is coupled through the correction signal coupler CPr and applied to the reference reception channel POPR to generate the reference channel signal chR, the sum channel signal chS, The relative phase and amplitude with respect to the secondary channel signals chD1 and chD2 can be obtained, and the error caused by the transmitter Syth is canceled.

The sum channel correction value and the first and second channel correction values are applied to the short term POPS and the first and second short term reception periods POPD1 and POPD2 after the sum reception, The first and second receiving and post-processing stages POPD1 and POPD2 directly perform the correcting operation. However, when the signal processor RV receives the short-term POPS and the first and second short- The sum channel signal chS and the first and second differential channel signals chD1 and chD2 receive the sum channel signal chS and the first and second differential channel signals chD1 and chD2, ) By software to correct the error by reflecting the sum channel correction value and the difference channel correction value.

In the above description, the signal processor RV is switched to the correction mode and the search mode to control the different components. However, in some cases, the signal processor RV is configured to simply determine the position of the target, And a separate control unit for controlling the element may be provided.

FIG. 4 illustrates a receive channel correction method of a monopulse radar system according to an embodiment of the present invention.

Referring to FIG. 3, when the monopulse radar system is operated, the signal processor RV operates in the correction mode and enters the rear-end correction mode in the correction mode. (S10). As described above, the post-stage correction mode is a mode in which the sum channel signal chS generated by the short-period (POPS), the first and second short-term reception (POPD1, POPD2) This is a mode for correcting the error of the second channel signals chD1 and chD2. In the rear end correction mode, the signal processor RV causes the transmitter Syth to generate the reception correction signal rcs, and the generated reception correction signal rcs is supplied to the plurality of reception shears PEP1 to PEPn and the monopulse distributor (POPR, POPS, POPD1, POPD2) to the signal processor (RV) without passing through the DVM. The signal processor RV receives the reference channel signal chR and the sum channel signal chS applied from the four reception short periods POPR, POPS, POPD1 and POPD2 and the first and second differential channel signals chD1 and chD2 (POPS), a sum channel for correcting the errors generated in the first and second short-term reception periods (POPD1, POPD2), and a correction value for each of the first and second difference channels (S20).

When the sum channel correction value and the first and second channel correction values are obtained, the signal processor RV enters the front end correction mode to correct an error occurring in each of the plurality of receiving shear units PEP1 to PEPn S30). In the front end correction mode, the signal processor RV causes the transmitter Syth to generate the reception correction signal rcs in the same manner as the rear end correction mode, sets the short term (POPR) ) To apply the reference channel signal (chR) to the signal processor (RV). However, the switch SW is controlled to select the N divider DV2, and the plurality of receiving shears PEP1 to PEPn are sequentially turned on to receive the reception correction signal rcs. The sum channel signal chS and the first and second differential channel signals chD1 and chD2 are applied to the signal processor RV for the reception correction signal rcs applied in the reception preamplifier in the on state, (RV) compares the applied reference channel signal (chR) with the sum channel signal (chS) and the first and second differential channel signals (chD1 and chD2) to obtain a correction value. Then, the summed channel correction value and the first and second channel correction values are subtracted from the obtained correction value, and a reception correction value for correcting the error generated in the selected reception shear is obtained (S40). The signal processor (RV) obtains the reception correction value in the same manner for the remaining reception shear.

Then, the obtained plurality of reception correction values are applied to a corresponding one of the plurality of receiving shearing units PEP1 to PEPn, and the sum channel correction value and the first and second difference correction values are summed POPS) and the first and second differential reception short periods POPD1 and POPD2 to apply correction values (S50).

When the correction operation is completed by applying the correction value, the signal processor RV switches the mode to the search mode (S60). In the search mode, the monopulse radar system is in the priority transmission mode, and the signal processor RV controls the transmitter Syth to generate the transmission signal ts and transmits it to the N distributor DV1. At this time, the POPR and the plurality of reception shear units PEP1 to PEPn are controlled to be in the OFF state after the reference reception. The transmission signal ts applied to the N divider DV1 is divided into a plurality of signals and amplified by the transmission amplifier TR to be applied to a corresponding one of the plurality of circulators CR1 to CRn to output a plurality of horn antennas H1- Hn (S70).

When the transmission signal is radiated, the signal processor RV controls the plurality of reception shear units PEP1 to PEPn to be on, and the radiated transmission signal is reflected on the target and transmitted to the plurality of horn antennas H1 to Hn, (S80). At this time, the plurality of circulators CR1 to CRn switch the signal transmission paths so that the reception signals received by the plurality of horn antennas H1 to Hn are applied to the plurality of reception shorting units PEP1 to PEPn.

Each of the plurality of receiving shearing devices PEP1 to PEPn corrects the phase and amplitude of the received signal in accordance with the received correction value applied in the correction mode and applies it to the mono pulse distributor (DVM). The monopulse distributor DVM divides the sum signal SIGMA and the azimuth difference signal SIG using a plurality of reception signals applied in each of the plurality of reception shear units PEP1 to PEPn according to the arrangement of the plurality of horn antennas H1 to Hn, (POPS) and first and second differential reception short-periods (POPD1, POPD2) in step S90.

(POPS) and the first and second differential reception short periods (POPD1 and POPD2) are set to a sum channel (?), An azimuth difference signal (? AZ) and a high angle difference signal (ChS) and the first and second differential channel signals (chD1 and chD2), and outputs the sum channel signal (chS) in accordance with the sum channel correction value applied in the correction mode and the first and second differential channel correction values The first and second channel signals chD1 and chD2 are corrected and applied to the signal processor RV (S100). At this time, the sum signal (Σ) and the azimuth difference signal (Σ) from the monopulse distributor (DVM) according to the control of the signal processor (RV) and the first and second short- And the high angle difference signal DELTA EL.

The signal processor RV analyzes the applied sum channel signal chS and the first and second differential channel signals chD1 and chD2 to determine the position of the target at step S110. Since the signal processor RV acquires the distance, azimuth and elevation angle of the target using the sum channel signal chS and the first and second difference channel signals chD1 and chD2 is a known technique, Do not.

If the position of the target is determined, the signal processor RV determines whether correction of the monopulse radar system is necessary (S120). In the monopulse radar system, as described above, the phase and amplitude fluctuations may occur due to time and temperature, so that the signal processor (RV) can determine the necessity of correction according to a predetermined period. Further, even when a separate correction command is applied from the outside, it can be determined that correction is necessary.

If it is determined that correction is not necessary, the signal processor RV maintains the search mode (S60). However, if it is determined that correction is necessary, the process goes back to the rear end correction mode (S10). As described above, the monopulse radar system can be switched to the correction mode according to a predetermined period or an instruction applied from the outside.

FIG. 5 is a detailed view illustrating a sum channel and a difference correction value acquisition step of FIG.

In the sum channel and difference correction value acquisition step S20, the signal processor RV first causes the transmitter Syth to generate a reception correction signal rcs (S21).

And controls the switch SW to select the correction signal distributor DV3 (S22).

(POPS) and the first and second differential reception short periods (POPD1 and POPD2) are received from the correction signal distributor DV3 by the reception correction signal rcs, So that the reception correction signal rcs is transmitted to the three short-term receivers (S22). At this time, the signal processor RV controls the plurality of reception shear devices PEP1 to PEPn to the off state.

In this case, the reference receiving channel (chR) generates the reference channel signal (chR) after receiving the reference signal, and the receiving signal (POPS) and the receiving signals (POPD1 and POPD2) And obtains the sum channel signal chS and the first and second differential channel signals chD1 and chD2 and applies the same to the signal processor RV (S24).

The signal processor RV compares the applied reference channel signal chR with the sum channel signal chS and the first and second differential channel signals chD1 and chD2 respectively and outputs the sum channel correction value and the first and second And acquires the channel correction value (S25).

FIG. 6 is a detailed view of the reception correction value acquisition step of FIG.

In the front end correction mode, the signal processor RV causes the transmitter Syth to generate the reception correction signal rcs and turns on the short term POPR after the reference reception (S41).

And the switch SW controls the selection of the N divider DV2 so that the short term POPS after the sum reception and the first and second short term POPD1 and POPD2 are received from the monopulse distributor DVM, the azimuth difference signal? AZ and the high angle difference signal? EL for the sum signal rcs in step S42.

Thereafter, the signal processor RV switches ON only one reception shear stage of the plurality of reception shear stages PEP1 to PEPn, and maintains the remaining reception shear stages OFF state (S43).

The on-state receiving shearer applies the received correction signal rcs applied from the N-divider DV2 to the mono pulse distributor DVM. The monopulse divider DVM generates the sum signal Σ, the azimuth difference signal ΔAZ and the high angle difference signal ΔEL using the applied reception correction signal rcs, And short-term periods POPD1 and POPD2 after the second reception (S44).

(POPS) and the first and second differential reception short periods (POPD1 and POPD2), to which the sum signal (?), The azimuth difference signal (DELTA AZ) and the high angle difference signal and the first and second differential channel signals chD1 and chD2 are applied to the signal processor RV and the reference short channel signal POPR is generated to generate a reference channel signal chR, (S45).

The signal processor RV compares the reference channel signal chR with the sum channel signal chS and the first and second differential channel signals chD1 and chD2 to calculate a correction value at step S46. In step S47, a reception correction value for the on-state reception front end is obtained by subtracting the sum channel correction value calculated in the rear-end correction mode and the first and second channel correction values from the calculated correction value.

When the reception correction value for one reception shear is obtained, the signal processor RV selects all reception shear devices PEP1 to PEPn to determine whether the reception correction value has been acquired (S48). If all the receive shear units PEP1 to PEPn have been selected, the correction value is applied (S50). However, if it is determined that the reception correction values for all the reception shearing devices PEP1 to PEPn have not been acquired, the other reception shearing devices are sequentially turned on to acquire the reception correction values in the same manner for the remaining reception shearing devices (S43).

As described above, in the reception channel correction method of the monopulse radar system of the present invention, a correction value for correcting the signal phase and amplitude error with respect to the short-term after reception in the correction mode is first obtained separately, By acquiring the value, it is possible to accurately obtain the correction value for the short term after receiving as well as the receiving short term. Therefore, it is possible to acquire the target distance, azimuth angle and elevation angle more precisely than the conventional monopulse radar.

The method according to the present invention can be implemented as a computer-readable code on a computer-readable recording medium. A computer-readable recording medium includes all kinds of recording apparatuses in which data that can be read by a computer system is stored. Examples of the recording medium include a ROM, a RAM, a CD-ROM, a magnetic tape, a floppy disk, an optical data storage device, and the like, and a carrier wave (for example, transmission via the Internet). The computer-readable recording medium may also be distributed over a networked computer system so that computer readable code can be stored and executed in a distributed manner.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is evident that many alternatives, modifications and variations will be apparent to those skilled in the art.

Accordingly, the true scope of the present invention should be determined by the technical idea of the appended claims.

Claims (7)

A transmitter including a transmitter, a transmission amplifier, a correction signal coupler, a switch, a transmitter including a first and a second N divider, and a plurality of couplers, a reception front end, a mono pulse distributor, a correction signal distributor, A receiving channel correction method of a monopulse radar system including a receiver and a receiver including a signal processor,
The receiving end of the reception correction signal generated by the transmitter in the post-end correction mode during the correction mode, receives the reference channel signal, the sum channel signal, and the first and second channel signals, A post-stage correction step of comparing the channel signal and the first and second channel signals with the reference channel signal to obtain a channel correction value for correcting an error occurring in the sum channel signal and the first and second channel signals; And
Acquiring first and second channel signals in a front end correction mode and a summing channel signal in a front end correction mode by using the reception correction signal applied to the reception front end in the front end correction mode during the correction mode, A front end correction for obtaining a reception correction value for correcting an error occurring between a plurality of reception channels of the reception front end by comparing the sum channel signal with the reference signal in the front end correction mode, step; Wherein the receiving channel correction method of the monopulse radar system comprises: The method according to claim 1,
Entering the back-end correction mode by the signal processor;
The transmitter generating the reception correction signal under the control of the signal processor;
Coupling the correction correction signal to the correction signal coupler and applying the correction signal to the reference reception rear end of the reception end to obtain the reference channel signal;
Dividing the reception correction signal applied from the switch, and transmitting the divided signals to the correction signal distributor in a short period after the summing reception at the rear end of the reception and at a short period after the first and second reception;
Receiving the sum channel signal and the first and second difference channel signals from the reception correction signal after the sum reception and the short term and after the first and second reception, respectively; And
The signal processor compares the sum channel signal with the first and second difference channel signals to obtain a sum channel correction value and a first and a second difference correction value as a channel correction value; Wherein the receiving channel correction method comprises the steps of: 3. The method as claimed in claim 2,
The signal processor entering a front end correction mode;
The transmitter generating the receive correction signal;
Coupling the correction correction signal to the reference signal reception end to obtain the reference channel signal;
Dividing the reception correction signal applied from the switch and transmitting the divided signals to each of a plurality of reception shear units of the reception front end through the plurality of couplers;
One of the plurality of reception shear stages, which is turned on in accordance with the control of the signal processor, transmits the reception correction signal to the mono pulse distributor;
Receiving the reception correction signal from the reception front end of the plurality of reception front end units, and generating a sum signal, an azimuth difference signal, and a high-angle difference signal using the reception correction signal;
Obtaining a first-stage correction mode combined channel signal and a first-order and second-order channel signal in the front-end correction mode from the sum signal, the azimuth difference signal, and the high-angle difference signal, respectively;
The signal processor compares the reference channel signal with the sum channel signal in the front end correction mode and the first and second channel signals in the front end correction mode to obtain a correction value, Obtaining the reception correction value corresponding to the reception preamble in the ON state by subtracting the first and second differential channel correction values; And
If it is determined that the reception correction value corresponding to each of the plurality of reception shears is acquired and that the reception correction value corresponding to each of the plurality of reception shears is not acquired, Sequentially turning on the reception shear stage in which the reception correction value is not obtained to acquire the reception correction value; Wherein the receiving channel correction method comprises the steps of: 4. The method of claim 3, wherein the shear correcting step
Applying the sum channel correction value and the first and second difference correction values obtained in the last stage correction step to the short term after the sum reception and the short term after the first and second reception; And
Applying the obtained plurality of reception correction values to each of the plurality of reception shearing units corresponding to the plurality of reception shearing units; Wherein the receiving channel correction method further comprises: 2. The method of claim 1, wherein the receiving channel correction method of the monopulse radar system comprises:
A transmitting step of emitting a transmission signal generated in the transmitter in a search mode through the plurality of antennas of the antenna unit; And
A plurality of reception signals received in each of the plurality of antennas are reflected on the transmission signal in the search mode, and a summing channel signal in a search mode and first and second A receiving step of acquiring a channel signal to determine a position of a target; Wherein the receiving channel correction method further comprises: 6. The method of claim 5, wherein the transmitting step
The transmitter generating the transmission signal;
Dividing a transmission signal generated by the transmitter into a plurality of signals by the first N distributor;
Amplifying the plurality of transmission signals distributed by the first N divider by the transmission amplifier; And
Radiating the amplified transmission signals through a corresponding antenna among the plurality of antennas of the antenna unit; Wherein the receiving channel correction method comprises: 6. The method of claim 5,
Wherein each of the plurality of reception shears receives a reception signal through a corresponding antenna among the plurality of antennas and corrects the reception signal in response to a corresponding reception correction value among the plurality of reception correction values, Transmitting;
The monopulse distributor generates the sum signal and the first and second difference signals using the reception signals applied to the plurality of reception shear devices, and outputs the sum signal and the first and second difference signals, Respectively;
The sum signal and the first and second difference signals are applied to the sum signal and the first and second difference signals, respectively, to convert the sum signal and the first and second difference signals into a predetermined mode, And obtaining a first channel signal and a second channel signal by using the sum channel correction value and the first and second channel correction values, Correcting the secondary channel signal; And
Wherein the signal processor receives and analyzes the search mode combined channel signal corrected from the short term after the sum reception and the short term after the first and second reception and the first and second differential channel signals in the search mode, Determining a position of the target; Wherein the receiving channel correction method comprises the steps of:

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