KR20220063582A - Apparatus and method for performing pulse decoding - Google Patents

Abstract

The present disclosure relates to a device and method for performing pulse decoding in consideration of interference caused by multipath in a communication system. According to the present disclosure, a method of operating a transponder comprises: a step of receiving a double pulse signal from a radar; a step of generating a first double pulse output signal by comparing the double pulse signal with a first reference voltage through a first voltage comparator; a step of generating a second double pulse output signal based on the double pulse signal and a second reference voltage through a second voltage comparator; a step of detecting rising edges of the first double pulse output signal and the second double pulse output signal through a controller; a step of performing pulse decoding based on a time difference value between the rising edges and a preset threshold section through the controller; and a step of transmitting a response pulse to the radar based on whether the pulse decoding is successful or not. The device and method according to various embodiments of the present disclosure enable the transponder to secure robustness from delay interference caused by multipath through a dual structure voltage comparator having low and high reception sensitivities.

Description

Apparatus and method for performing pulse decoding

The present disclosure generally relates to a wireless communication system, and more particularly, to an apparatus and method for performing pulse decoding in consideration of multipath interference in a wireless communication system.

A transponder is mounted on the vehicle so that ground tracking radar can track the vehicle's location. A transponder is a two-way communication device that has a single transceiver, is mounted on an aircraft, receives a promised RF pulse signal from a ground tracking radar, and transmits a response pulse. The transponder receives a modulated signal having a pulse interval coded from the radar and performs pulse decoding. The transponder transmits a response pulse to the radar when the pulse decoding is successfully performed. The transponder does not transmit a response pulse to the radar if the pulse decoding is not successfully performed.

In a process in which the transponder decodes the pulse signal received from the radar, the pulse signal may not be recognized as a normal code due to interference by multiple paths of the pulse signal. As the transponder does not recognize the received pulse signal as a normal code, the transponder does not transmit a response pulse, and as a result, the tracking performance of the radar may be deteriorated.

Accordingly, in order to improve the tracking performance of the radar, a technique for securing robustness from interference due to multi-path signals in pulse decoding of a transponder is required.

Based on the above discussion, the present disclosure provides an apparatus and method for enabling a transponder to secure robustness against delayed interference due to a propagation path of a signal.

According to various embodiments of the present disclosure, a method of operating a transponder may include receiving a double pulse signal from a radar; generating a first double pulse output signal by comparing the double pulse signal with a first reference voltage through a first voltage comparator; generating a second double pulse output signal based on the double pulse signal and a second reference voltage through a second voltage comparator; detecting, through a controller, rising edges of the first double pulse output signal and the second double pulse output signal; performing, through the controller, pulse decoding based on a time difference value between the rising edges and a preset threshold period; and transmitting a response pulse to the radar based on whether the pulse decoding is successful.

According to another embodiment, the double pulse signal is input to each of the first voltage comparator and the second voltage comparator.

According to another exemplary embodiment, the level of the first reference voltage is set to satisfy the minimum reception sensitivity standard and is smaller than the voltage level of the interference signal due to propagation delay, and the level of the second reference voltage depends on the propagation delay of the signal. It is set larger than the voltage level of the interference signal.

According to another embodiment, the detecting of the rising edges of the first double pulse output signal and the second double pulse output signal includes detecting the first rising edge and the second rising edge of the first double pulse output signal. step; and detecting a third rising edge and a fourth rising edge of the second double pulse output signal.

According to another embodiment, identifying whether the pulse decoding is successful may include: measuring a first time difference value between the first rising edge and the second rising edge; identifying whether the first time difference value is included in the threshold interval; measuring a second time difference value between the third rising edge and the fourth rising edge; identifying whether the second time difference value is included in the threshold interval; and when it is identified that at least one of the first time difference value and the second time difference value is included in the preset threshold period, identifying that the pulse decoding is successful.

According to another embodiment, in the step of identifying whether the pulse decoding is successful, at least one of the second rising edge and the fourth rising edge is detected within a time corresponding to the threshold section from the first rising edge and identifying that the pulse decoding was successful if so.

According to an embodiment of the present disclosure, a transponder includes: a receiver configured to receive a double pulse signal from a radar; a first voltage comparator configured to compare the double pulse signal with a first reference voltage to generate a first double pulse output signal; a second voltage comparator generating a second double pulse output signal by comparing the double pulse signal with a second reference voltage, and rising edges of the first double pulse output signal and the second double pulse output signal a controller for detecting and performing pulse decoding based on a time difference value between the rising edges and a preset threshold period; and a transmitter for transmitting a response pulse to the radar based on whether the pulse decoding is successful.

According to another embodiment, the double pulse signal is input to each of the first voltage comparator and the second voltage comparator.

According to another exemplary embodiment, the level of the first reference voltage is set to be smaller than the voltage level of the interference signal due to propagation delay, and the level of the second reference voltage is higher than the voltage level of the interference signal due to the signal propagation delay. set to large.

According to another embodiment, the controller detects a first rising edge and a second rising edge of the first double pulse output signal, and detects a third rising edge and a fourth rising edge of the second double pulse output signal.

According to another embodiment, the controller measures a first time difference value between the first rising edge and the second rising edge, and identifies whether the first time difference value is included in the threshold section, and the Measure a second time difference value between the third rising edge and the fourth rising edge, identify whether the second time difference value is included in the threshold section, and the first time difference value and the second time difference When it is identified that at least one of the values is included in the preset threshold section, it is identified that the pulse decoding is successful.

According to another embodiment, the controller identifies that the pulse decoding is successful when at least one of the second rising edge and the fourth rising edge is detected within a time corresponding to the threshold section from the first rising edge do.

Various respective aspects and features of the invention are defined in the appended claims. Combinations of features of the dependent claims may be combined with features of the independent claims as appropriate, not just expressly set forth in the claims.

In addition, one or more features selected in any one embodiment described in this disclosure may be combined with one or more features selected in any other embodiment described in this disclosure, and alternatives to these features a combination of at least partially alleviates one or more technical problems discussed in the present disclosure, or at least partially alleviates technical problems that can be discerned by a person skilled in the art from the present disclosure, and furthermore features of embodiments ( The combination is possible, provided that a specific combination or permutation so formed of the embodiment features is not understood by a person skilled in the art as incompatible.

In any described example implementation, two or more physically separate components may alternatively be integrated into a single component if their integration is possible, and the single component so formed If the same function is performed by , the integration is possible. Conversely, a single component of any embodiment described in the present disclosure may alternatively be implemented with two or more separate components that achieve the same function, where appropriate.

It is an object of certain embodiments of the present invention to solve, mitigate, or eliminate, at least in part, at least one of the problems and/or disadvantages associated with the prior art. Certain embodiments aim to provide at least one of the advantages described below.

The apparatus and method according to various embodiments of the present disclosure enable a transponder to secure robustness against delayed interference due to multipath through a voltage comparator having a dual structure having low reception sensitivity and high reception sensitivity.

Effects obtainable in the present disclosure are not limited to the above-mentioned effects, and other effects not mentioned may be clearly understood by those of ordinary skill in the art to which the present disclosure belongs from the description below. will be.

1 illustrates a communication system according to various embodiments of the present disclosure.
2 illustrates an example of a pulse signal transmitted and received by a transponder in a communication system according to various embodiments of the present disclosure.
3 is a block diagram of a transponder in a communication system according to various embodiments of the present disclosure;
4 illustrates an example of a pulse interval measured by a transponder in a communication system according to various embodiments of the present disclosure.
5 is a block diagram of a transponder including a dual structure of a voltage comparator in a communication system according to various embodiments of the present disclosure;
6 illustrates an example of a pulse interval measured by a transponder including a dual structure of a voltage comparator in a communication system according to various embodiments of the present disclosure.
7 illustrates an example of a method of determining whether a pulse interval condition is satisfied in a communication system according to various embodiments of the present disclosure.
8 is a flowchart illustrating a method of operating a transponder in a communication system according to various embodiments of the present disclosure.

Terms used in the present disclosure are used only to describe specific embodiments, and may not be intended to limit the scope of other embodiments. The singular expression may include the plural expression unless the context clearly dictates otherwise. Terms used herein, including technical or scientific terms, may have the same meanings as commonly understood by one of ordinary skill in the art described in the present disclosure. Among the terms used in the present disclosure, terms defined in a general dictionary may be interpreted with the same or similar meaning as the meaning in the context of the related art, and unless explicitly defined in the present disclosure, ideal or excessively formal meanings is not interpreted as In some cases, even terms defined in the present disclosure cannot be construed to exclude embodiments of the present disclosure.

In various embodiments of the present disclosure described below, a hardware access method will be described as an example. However, since various embodiments of the present disclosure include technology using both hardware and software, various embodiments of the present disclosure do not exclude a software-based approach.

Hereinafter, the present disclosure relates to an apparatus and method for performing pulse decoding in a wireless communication system. Specifically, the present disclosure describes a technique for performing pulse decoding in consideration of delayed interference due to multipath in a wireless communication system.

Hereinafter, various embodiments will be described in detail with reference to the accompanying drawings so that those of ordinary skill in the art to which the present disclosure pertains can easily implement it. However, since the technical spirit of the present disclosure may be modified and implemented in various forms, it is not limited to the embodiments described herein. In the description of the embodiments disclosed in the present specification, when it is determined that a detailed description of a related known technology may obscure the gist of the present disclosure, a detailed description of the known technology will be omitted. The same or similar components are given the same reference numerals, and overlapping descriptions thereof will be omitted.

In the present specification, when an element is described as being "connected" with another element, it includes not only the case of being "directly connected" but also the case of being "indirectly connected" with another element interposed therebetween. When an element "includes" another element, it means that another element may be further included without excluding another element in addition to other elements unless otherwise stated.

Some embodiments may be described in terms of functional block configurations and various processing steps. Some or all of these functional blocks may be implemented in various numbers of hardware and/or software configurations that perform specific functions. For example, the functional blocks of the present disclosure may be implemented by one or more microprocessors, or by circuit configurations for a given function. The functional blocks of the present disclosure may be implemented in various programming or scripting languages. The functional blocks of the present disclosure may be implemented as an algorithm running on one or more processors. A function performed by a functional block of the present disclosure may be performed by a plurality of functional blocks, or functions performed by a plurality of functional blocks in the present disclosure may be performed by one functional block. In addition, the present disclosure may employ prior art for electronic configuration, signal processing, and/or data processing, and the like.

In addition, in the present disclosure, in order to determine whether a specific condition is satisfied (satisfied) or satisfied (fulfilled), an expression of more than or less than is used, but this is only a description to express an example, and more or less description is excluded not to do Conditions described as 'more than' may be replaced with 'more than', conditions described as 'less than', and conditions described as 'more than and less than' may be replaced with 'more than and less than'.

1 illustrates a communication system 100 according to various embodiments of the present disclosure. Referring to FIG. 1 , the communication system 100 includes a radar 101 and a transponder 103 .

The radar 101 performs a function of detecting an object using radio waves and measuring a distance. The radar 101 includes a transmitter and a receiver connected to an antenna. The transmitter transmits a pulse that is modulated using amplitude modulation. To form a pulse, the carrier frequency provided by the oscillator or clock is subjected to pulse modulation. The radar 101 couples the modulated pulse signal to the antenna using a power amplifier and generates an output signal.

The transponder 103 is mounted on the aircraft and includes a transmitter and a receiver. The aircraft includes communication system devices such as an antenna and a transponder, and the transponder performs a function of receiving an RF signal transmitted from a ground radar and transmitting a response signal.

According to an embodiment of the present disclosure, the radar 101 transmits a double pulse signal to a transponder mounted on a projectile in order to measure the position of the projectile or measure the distance to the projectile. The signal transmitted by the radar to the transponder may include an amplitude-modulated double pulse signal in which a pulse interval is coded. According to an embodiment of the present disclosure, the transponder 103 may receive a double pulse signal from the radar and transmit a response signal corresponding to the double pulse signal. The transponder 103 may decode the double pulse signal received from the radar and, when the pulse decoding is successfully performed, transmit a response pulse signal to the radar. The radar 101 may receive a response pulse from the transponder to track the location of the projectile. According to an embodiment of the present disclosure, the transponder 103 does not transmit a response pulse signal when the pulse decoding is not successfully performed. The radar 101 cannot receive a response pulse from the transponder, so it cannot track the location of the projectile.

2 illustrates an example 200 of a pulse signal transmitted and received by a transponder in a communication system according to various embodiments of the present disclosure. FIG. 2 shows an example of a pulse signal received and a pulse signal transmitted by the transponder 103 of FIG. 1 . Referring to FIG. 2 , the transponder receives a receive pulse signal 201 and transmits a transmit pulse signal 203 . In the reception pulse signal 201 and the transmission pulse signal 203 of FIG. 2 , the horizontal axis indicates time and the vertical axis indicates amplitude. According to an embodiment of the present disclosure, a vertical axis indicates a voltage.

The received pulse signal 201 indicates a double pulse signal received by the transponder from the radar. According to an embodiment of the present disclosure, the reception pulse signal 201 may have the form of a double pulse. The transmit pulse signal 203 indicates a pulse signal that the transponder transmits to the radar. The transmit pulse signal 203 may have the form of a single pulse.

According to an embodiment of the present disclosure, the transponder 103 receives a double pulse signal having a pulse interval coded from the radar. The transponder 103 may recognize rising edges of the double pulse, and may determine the interval t _ps (205) between the double pulses of the received pulse signal using the interval between the rising edges. The transponder 103 identifies whether an interval t _ps (205) between double pulses is within a predetermined interval range in order to perform pulse decoding of the received double pulse signal.

According to an embodiment of the present disclosure, when the interval t _ps (205) between double pulses recognized by the transponder satisfies <Equation 1>, the transponder may identify that the pulse decoding has been successfully performed. .

Referring to <Equation 1>, t _ps is the interval between double pulses recognized by the transponder, t _L is the minimum reference value for identifying that the pulse decoding is successful, and t _H is the maximum for identifying that the pulse decoding is successful Indicates the reference value. According to an embodiment of the present disclosure, t _L and t _H may be freely set according to a user's setting.

When t _ps satisfies the condition shown in Equation 1, the transponder 103 recognizes the received double pulse signal as an appropriate code and transmits a response signal. The radar can receive the response pulses to track the location of the projectile. When t _ps does not satisfy a condition such as Equation 1, the transponder 103 recognizes the received double pulse signal as an inappropriate code and does not transmit a response pulse.

3 illustrates a block diagram 300 of a transponder in a communication system according to various embodiments of the present disclosure.

Referring to FIG. 3 , the transponder includes an antenna 301 , a circulator 303 , a bandpass filter 305 , a low noise amplifier 307 , an envelope detector 309 , a voltage comparator 311 , and a reference voltage generator 313 . ), a controller 315 , and a transmitter 317 .

According to an embodiment of the present disclosure, the antenna 301 performs a function of transmitting or receiving a radio signal in the form of an electromagnetic wave. The circulator 303 performs a function of separating an RF transmission/reception path. According to an embodiment of the present disclosure, the circulator 303 performs a function of a transmission/reception duplexer. The band-pass filter (BPF) 305 performs a function of passing only signals between specific frequencies. The low noise amplifier (LNA) 307 performs a function of amplifying a small radio frequency (RF) signal. The envelope detector 309 performs a function of demodulating the modulated signal. According to an embodiment of the present disclosure, the magnitude of the output signal V _IN1 of the envelope detector may be different according to the received pulse power.

The voltage comparator 311 compares two input voltages to generate an output signal. The voltage comparator 311 compares at least two input voltages to generate an output signal. According to an embodiment of the present disclosure, the voltage comparator 311 may generate an output signal outputting high or low by comparing two input voltages V _IN1 and V _IN2 . According to an embodiment of the present disclosure, the voltage comparator 311 may generate an output signal that becomes high when V _IN1 is greater than V _IN2 and becomes low when V _IN1 is less than V _IN2 .

The reference voltage generator 313 performs a function of generating a reference voltage used for voltage comparison. According to an embodiment of the present disclosure, the reference voltage may be adjusted using a constant voltage and resistors R1 and R2. According to an embodiment of the present disclosure, V _IN2 may be determined based on a minimum reception sensitivity requirement standard of a transponder for long-distance communication with a radar. According to another embodiment of the present disclosure, V _IN2 may be changed according to a user's setting.

The controller 315 recognizes the rising edge of the signal input from the voltage comparator, and determines the interval between the rising edge and the double pulse. The controller 315 identifies whether the interval between double pulses satisfies a value within a predefined interval. According to an embodiment of the present disclosure, the output signal of the voltage comparator is input to the controller as a binarized output signal, and the controller 315 detects a rising edge of the input signal, and a minimum reference value for identifying pulse decoding success. It is identified whether t _ps satisfying a value between t _L and a maximum reference value t _H for identifying success of pulse decoding exists. According to an embodiment of the present disclosure, the control unit includes a field programmable gate array (FPGA).

The transmitter 317 performs a function of transmitting a response signal.

According to an embodiment of the present disclosure, the transponder is based on a bandpass filter 305 , a low noise amplifier 307 , an envelope detector 309 , a voltage comparator 311 , a reference voltage generator 313 , and a controller 315 . Thus, the amplitude-modulated pulse signal can be demodulated. According to an embodiment of the present disclosure, the transponder may further include a local oscillator (LO) and a mixer for down conversion to an intermediate frequency (IF) band.

4 illustrates an example of a pulse interval measured by a transponder in a communication system according to various embodiments of the present disclosure. FIG. 4 shows an example of a pulse interval measured by the transponder of FIG. 3 . 4 , the horizontal axis indicates time and the vertical axis indicates amplitude. According to an embodiment of the present disclosure, a vertical axis indicates a voltage.

Referring to FIG. 4 , the envelope detector output signal V _IN1 401 may be generated in the form of a double pulse, and the reference voltage V _IN2 403 may be generated in the form of a constant voltage having a preset magnitude. The delayed signal 405 indicates a signal with weak signal power and delayed time because of a longer propagation path compared to the straight-line signal. The voltage comparator output signal 407 may be generated based on a process of comparing V _IN1 and V _IN2 .

가 펄스 디코딩 성공을 식별하기 위한 최소 기준 값 t_L보다 작은 경우, 트랜스폰더는 펄스 디코딩이 실패한 것으로 식별하고 응답 펄스를 송신하지 않을 수 있다.According to an embodiment of the present disclosure, in the case of the initial flight state of the projectile, the distance between the projectile and the radar is short, so the line of sight (LOS) signal power received by the transponder is large, but the altitude of the projectile is low, including surrounding terrain features Interference of multipath signals may occur depending on the environment. In the signal received from the radar, when the first pulse due to the multipath delay exists adjacent to the second pulse of the straight forward signal, the delayed signal of the first pulse and the straight forward signal of the second pulse may interfere. Due to the presence of multipath propagation delay, the voltage comparator may produce an output signal with distorted pulse spacing. If the interval between the double pulses received from the transponder is distorted, the transponder may not recognize the received signal as a normal code and may not transmit a response pulse. An output signal having a distorted pulse interval may affect the estimation performance of the radar. According to an embodiment of the present disclosure, a distorted pulse interval

is less than the minimum reference value t _L for identifying pulse decoding success, the transponder may identify that the pulse decoding has failed and not transmit a response pulse.

According to an embodiment of the present disclosure, the envelope detector 309 generates an output signal V _IN1 401 in the form of a double pulse based on a signal received from the radar. The envelope detector 309 generates a delayed signal 405 having a relatively delayed signal compared to the V _IN1 output signal and having a weak signal power according to the propagation delay due to the multipath. The reference voltage generator 313 generates a reference voltage V _IN2 403 set according to a user's setting. The output signal 401 of the envelope detector, the delay signal 405, and the output signal 403 of the reference voltage generator are input to the voltage comparator. The voltage comparator 311 compares signals received from the envelope detector 309 and the reference voltage generator 313 and outputs a pulse signal.

According to an embodiment of the present disclosure, when propagation delay due to multipath is not considered, the voltage comparator 311 may generate an output signal by comparing output signals V _IN1 and V _IN2 of the envelope detector. The voltage comparator 311 outputs an output signal so that the voltage of V _IN1 has a first voltage output value when the voltage is greater than the voltage of V _IN2 and has a second voltage output value when the voltage of V _IN1 is less than the voltage of V _IN2 . can create

According to an embodiment of the present disclosure, when the propagation delay due to multipath is considered, the voltage comparator 311 compares the voltages of V _IN1 401 and the delay signal 405 with V _IN2 403 to generate an output signal. can do. When the first pulse of the multi-path signal interferes with the second pulse of the straight-path signal due to propagation delay due to the multi-path, the voltage comparator determines that at least one of the voltages of V _IN1 401 and delay signal 405 is higher than V _IN2 . The output signal may be generated to have the first voltage output value at a larger time and to have the second voltage output value at a time when the voltage of V _IN1 and the voltage of the delay signal are smaller than the voltage of V _IN2 . According to an embodiment of the present disclosure, the first voltage output value indicates a high value of the pulse signal, and the second voltage output value indicates a low value of the pulse signal.

According to an embodiment of the present disclosure, the voltage comparator output signal 407 may be generated based on voltages of V _IN1 , V _{IN2 ,} and a delay signal. The voltage comparator output signal 407 is an output signal having a rising edge at a time when the voltage of V _IN1 or the delay signal becomes greater than V _IN2 and a falling edge at a time when the voltage of V _IN1 and the delay signal becomes smaller than V _IN2 of the delay signal. can create

5 illustrates a block diagram 500 of a transponder including a dual structure of a voltage comparator in a communication system according to various embodiments of the present disclosure. Although FIG. 5 illustrates a transponder in which a voltage comparator and a reference voltage generator are double connected in FIG. 3 , the transponder may include a plurality of voltage comparators and a plurality of reference voltage generators according to a user's design.

Referring to FIG. 5 , the transponder includes an antenna 501 , a circulator 503 , a bandpass filter 505 , a low noise amplifier 507 , an envelope detector 509 , a first voltage comparator 511-1, and a second 2 includes a voltage comparator 511 - 2 , a first reference voltage generator 513 - 1 , a second reference voltage generator 513 - 2 , a controller 515 , and a transmitter 517 . According to an embodiment of the present disclosure, the antenna 501 , the circulator 503 , the bandpass filter 505 , the low noise amplifier 507 , the envelope detector 509 , and the transmitter 517 each correspond to FIG. 3 . It performs the same function as the components.

According to an embodiment of the present disclosure, the transponder includes a structure in which voltage comparators are double connected. The output signal of the envelope detector 509 is input to the first voltage comparator 511-1 and the second voltage comparator 511-2. The first voltage comparator 511-1 may generate an output signal outputting high or low by comparing the voltage input from the envelope detector with the voltage input from the first reference voltage generator 513-1. The second voltage comparator 511 - 2 may generate an output signal outputting high or low by comparing the voltage input from the envelope detector with the voltage input from the second reference voltage generator 513 - 2 .

According to an embodiment of the present disclosure, the first reference voltage generator 513 - 1 may adjust the value of the first reference voltage using resistors R1 and R2 . The second reference voltage generator 513 - 2 may adjust the value of the second reference voltage using resistors R3 and R4 . According to an embodiment of the present disclosure, the level of the first reference voltage is set to be smaller than the voltage level of the interference signal due to propagation delay in order to satisfy the minimum reception sensitivity standard, and the level of the second reference voltage depends on the propagation delay of the signal. may be set to be larger than the voltage level of the interference signal. According to another embodiment of the present disclosure, the first reference voltage and the second reference voltage may be changed according to a user's setting.

The controller 515 recognizes the rising edge of the input signal, and identifies whether the interval between double pulses satisfies a value within a predefined section. According to an embodiment of the present disclosure, the output signal of the first voltage comparator 511-1 and the output signal of the second voltage comparator 511-2 are each input to the controller as a binarized output signal. The controller 515 detects the rising edges of the input signals, and t _ps that satisfies a value between the minimum reference value t _L for identifying pulse decoding success and the maximum reference value t _H for identifying pulse decoding success is Identifies whether it exists or not. According to an embodiment of the present disclosure, the control unit includes a field programmable gate array (FPGA).

According to an embodiment of the present disclosure, the transponder includes a bandpass filter 505 , a low noise amplifier 507 , an envelope detector 509 , a first voltage comparator 511-1, and a second voltage comparator 511-2. , the first reference voltage generator 513 - 1 , the second reference voltage generator 513 - 2 may demodulate the amplitude modulated pulse signal based on the controller 515 . According to an embodiment of the present disclosure, the transponder may further include a local oscillator (LO) and a mixer for down conversion to an intermediate frequency (IF) band.

6 illustrates an example 600 of a pulse interval measured by a transponder including a dual structure of a voltage comparator in a communication system according to various embodiments of the present disclosure. 6 shows an example of a pulse interval measured by the transponder of FIG. 5 . 6 , the horizontal axis indicates time and the vertical axis indicates amplitude. According to an embodiment of the present disclosure, a vertical axis indicates a voltage.

Referring to FIG. 6 , the envelope detector output signal V _IN1 (601) is generated in the form of a double pulse, and the first reference voltage V _IN21 (603) and the second reference voltage V _IN22 (605) are constant voltages having a preset size. can be created in the form The delayed signal 607 indicates a delayed signal having a weaker signal power because a propagation path is longer than that of the straight-line signal. The output signal 609 of the first voltage comparator may be generated by comparing V _IN1 and V _IN21 . The output signal 611 of the second voltage comparator may be generated by comparing V _IN1 and V _IN22 . According to an embodiment of the present disclosure, the magnitude of the voltage V _IN22 may be set to be greater than the magnitude of the voltage V _IN21 .

According to an embodiment of the present disclosure, the envelope detector 509 generates an output signal V _IN1 601 in the form of a double pulse based on a signal received from the radar. The envelope detector 509 generates a delayed signal 605 having a relatively delayed signal and weak signal power compared to the V _IN1 output signal according to the propagation delay due to multipath. The first reference voltage generator 513 - 1 generates a reference voltage V _IN21 603 set according to a user's setting. The second reference voltage generator 513 - 2 generates a reference voltage V _IN22 605 set according to a user's setting. The output signal 601 of the envelope detector, the delay signal 607, and the output signal 603 of the first reference voltage generator are input to the first voltage comparator. The first voltage comparator 511-1 compares signals received from the envelope detector 509 and the first reference voltage generator 513-1 and outputs a pulse signal. The output signal 601 of the envelope detector, the delay signal 607, and the output signal 605 of the second reference voltage generator are input to the second voltage comparator. The second voltage comparator 511 - 2 compares the signals received from the envelope detector 509 and the second reference voltage generator 513 - 2 and outputs a pulse signal.

When the first pulse of the multi-path signal interferes with the second pulse of the straight-path signal due to propagation delay due to the multi-path, the first voltage comparator 511-1 converts V _IN1 601 and the delay signal 607 to V Comparison with _IN21 603 may generate an output signal. The first voltage comparator has a first voltage output value at a time when at least one of the voltages of V _IN1 601 and the delay signal 607 is greater than V _IN21 , and the voltages of V _IN1 601 and the delay signal 607 are An output signal may be generated to have the second voltage output value at a time less than V _IN21 . According to an embodiment of the present disclosure, the first voltage output value indicates a high value of the pulse signal, and the second voltage output value indicates a low value of the pulse signal.

According to an embodiment of the present disclosure, the first voltage comparator output signal 609 may be generated based on the comparison result of the first voltage comparator. The first voltage comparator output signal 609 may be generated based on voltages of V _IN1 , V _IN21 and the delay signal. The first voltage comparator output signal 609 has a rising edge at a time when the voltage of V _IN1 or the delay signal becomes greater than V _IN21 and a falling edge at a time when the voltage of V _IN1 and the delay signal becomes smaller than V _IN21 . can create

When the first pulse of the multi-path signal interferes with the second pulse of the straight-path signal due to the propagation delay due to the multi-path, the second voltage comparator 511 - 2 sets the voltages of V _IN1 601 and the delay signal 607 . can be compared to V _IN22 605 to generate an output signal. The second voltage comparator has a first voltage output value at a time when at least one of the voltages of V _IN1 601 and the delay signal 607 is greater than V _IN22 , and the voltage of V _IN1 and the delay signal 607 is greater than V _IN22 The output signal may be generated to have the second voltage output value at a small time. According to an embodiment of the present disclosure, the first voltage output value indicates a high value of the pulse signal, and the second voltage output value indicates a low value of the pulse signal.

According to an embodiment of the present disclosure, the second voltage comparator output signal 611 may be generated based on the comparison result of the second voltage comparator. The second voltage comparator output signal 611 may be generated based on voltages of V _IN1 , V _IN22 and the delay signal. The second voltage comparator output signal 611 is an output signal having a rising edge at a time when the voltage of V _IN1 or the delay signal becomes greater than V _IN22 and a falling edge at a time when the voltage of V _IN1 and the delay signal becomes smaller than V _IN22 . can create According to an embodiment of the present disclosure, the first pulse of the first voltage comparator output signal 609 and the first pulse of the second voltage comparator output signal 611 may be identified as having the same value within an error range. According to an embodiment of the present disclosure, the transponder may identify the first rising edge of the first voltage comparator output signal and the third rising edge of the second voltage comparator output signal as having the same value.

According to an embodiment of the present disclosure, as propagation delay due to multipath exists, the first voltage comparator may generate an output signal having a distorted pulse interval t _PS1 . However, the second voltage comparator may generate an output signal having a normal pulse interval t _PS2 by comparing the intensity of the voltage with respect to the second reference voltage. The transponder may perform pulse decoding based on the output signal of the second voltage comparator. According to an embodiment of the present disclosure, the transponder may recognize a received double pulse signal and identify whether to transmit a response signal by including a configuration with high reception sensitivity so that a signal propagated through a multipath is ignored.

7 illustrates an example 700 of a method of determining whether a pulse interval condition is satisfied in a communication system according to various embodiments of the present disclosure. The horizontal axis of FIG. 7 indicates time, and the arrow indicates a rising edge detected by a controller included in the transponder.

7, t ₁ (701) is the rising edge of the first pulse, t _2a (703) is the rising edge of the second pulse in the distorted pulse signal output from the first voltage comparator, t _2b (705) is the second The rising edge of the second pulse in the pulse signal output from the voltage comparator, t _L (707) is the minimum reference value for identifying that the pulse decoding is successful, t _H (709) is the maximum reference value for identifying that the pulse decoding is successful instruct

According to an embodiment of the present disclosure, when there is a rising edge satisfying the t _L and t _H ranges by counting the pulse interval based on t ₁ 701 , the transponder identifies that the pulse decoding is successful. When the double pulse interval recognized by the control unit is greater than the time interval of t ₁ (701) and t _L (707) and smaller than the time interval of t ₁ (701) and t _H (709), the transponder determines that the pulse decoding is successful. Identifies and sends a response signal.

According to another embodiment of the present disclosure, the controller 515 included in the transponder is a method of identifying whether a rising edge exists within the range of t _L to t _H , and the pulses of the first voltage comparator and the second voltage comparator Intervals can be identified by calculating each of them. According to an embodiment of the present disclosure, the controller receives the output signals of the first voltage comparator 511-1 and the second voltage comparator 511-2 and detects a rising edge. The controller calculates a pulse interval value t _ps1 between t ₁ ( 701 ) and t _2a ( 703 ) and a pulse interval value t _ps2 between t ₁ ( 701 ) and t _2b ( 705 ). The controller identifies whether at least one of t _ps1 and t _ps2 is greater than a time interval value from t ₁ to t _L and less than a time interval value from t ₁ to t _H . When the controller identifies that at least one of t _ps1 and t _ps2 is greater than the t ₁ to t _L time interval value and less than the t ₁ to t _H time interval value, the controller performs pulse decoding and transmits a response signal.

If pulse decoding cannot be performed with the first voltage comparator with low reception sensitivity due to signal interference due to multipath propagation delay, the controller performs pulse decoding without being affected by the interference signal using the second voltage comparator with high reception sensitivity. can be done According to an embodiment of the present disclosure, when the controller detects t _2a using the first voltage comparator and detects t _2b using the second voltage comparator, even if there is a signal outside the window like t _2a , t _2b is the window Since it is inside, pulse decoding can be performed. According to the present disclosure, although t _2b is exemplified between t _L to t _H , t _2a may exist between t _L to t _H in case of long-distance communication having low received power. When t _2a exists between t _L to t _H , the controller may perform pulse decoding using the first voltage comparator and transmit a response signal.

8 is a flowchart illustrating a method of operating a transponder in a communication system according to various embodiments of the present disclosure. 8 illustrates a method of operation of the transponder of FIG. 5 .

Referring to FIG. 8 , in step 801 , the transponder receives a double pulse signal from the radar. According to an embodiment of the present disclosure, the double pulse signal includes a signal for tracking the position of the projectile.

In step 803, the transponder compares the double pulse signal with the first reference voltage through the first voltage comparator to generate a first double pulse output signal. According to an embodiment of the present disclosure, the first voltage comparator may generate an output signal outputting high or low by comparing the voltage input from the envelope detector with the voltage input from the first reference voltage generator.

In step 805 , the transponder generates a second double pulse output signal based on the double pulse signal and the second reference voltage through the second voltage comparator. According to an embodiment of the present disclosure, the second voltage comparator may generate an output signal outputting high or low by comparing the voltage inputted from the envelope detector with the voltage inputted from the second reference voltage generator 513-2. there is. According to an embodiment of the present disclosure, the double pulse signal is input to each of the first voltage comparator and the second voltage comparator. According to an embodiment of the present disclosure, the level of the first reference voltage is set to be smaller than the voltage level of the interference signal due to propagation delay, and the level of the second reference voltage is greater than the voltage level of the interference signal due to the signal propagation delay. can be set.

In step 807, the transponder detects, through the controller, rising edges of the first double pulse output signal and the second double pulse output signal. According to an embodiment of the present disclosure, the controller detects rising edges in each of the signal input from the first voltage comparator and the signal input from the second voltage comparator. According to an embodiment of the present disclosure, the controller detects the first rising edge and the second rising edge of the first double pulse output signal, and detects the third rising edge and the fourth rising edge of the second double pulse output signal. can

In step 809, the transponder performs pulse decoding based on the time difference value between the rising edges and a preset threshold period through the controller. According to an embodiment of the present disclosure, the time difference value indicates a pulse interval value regarding the interval between rising edges based on the first double pulse output signal and the second double pulse output signal. According to an embodiment of the present disclosure, the threshold period indicates a value between a minimum reference value t _L for identifying success of pulse decoding and a maximum reference value t _H for identifying success of pulse decoding. The threshold section may be changed according to a user's setting. According to an embodiment of the present disclosure, the controller identifies whether a pulse interval value related to a time interval of the detected rising edges satisfies a threshold interval condition. The controller recognizes the received signal as an appropriate signal and performs pulse decoding when it is identified that the time difference value with respect to the pulse interval between the threshold intervals exists within the threshold interval.

According to an embodiment of the present disclosure, the controller measures the first time difference value between the first rising edge and the second rising edge of the first double pulse output signal, and determines whether the first time difference value is included in the threshold section identify The controller measures a second time difference value between the third rising edge and the fourth rising edge of the second double pulse output signal, and identifies whether the second time difference value is included in the threshold section. When at least one of the first time difference value and the second time difference value is identified as being included in the threshold period, the controller identifies that the pulse decoding is successful.

According to another embodiment of the present disclosure, the controller detects at least one of a second rising edge and the fourth rising edge from a first rising edge of the first double pulse output signal, within a time corresponding to a threshold section. The controller identifies that the pulse decoding is successful when at least one of the second rising edge or the fourth rising edge is detected within the threshold period.

In step 811, the transponder transmits a response pulse to the radar based on whether the pulse decoding is successful. According to an embodiment of the present disclosure, when it is identified that the pulse decoding has been successfully performed, the transponder transmits a response pulse to the radar using a transmitter.

According to the present disclosure, the transponder includes a dual structure having low reception sensitivity and high reception sensitivity in AM pulse demodulation. According to the present disclosure, a development burden can be reduced by a simple update of adding a voltage comparator and adding an OR operation to the firmware of the FPGA.

Methods according to the embodiments described in the claims or specifications of the present disclosure may be implemented in the form of hardware, software, or a combination of hardware and software.

When implemented in software, a computer-readable storage medium storing one or more programs (software modules) may be provided. One or more programs stored in the computer-readable storage medium are configured to be executable by one or more processors in an electronic device (device). One or more programs include instructions for causing an electronic device to execute methods according to embodiments described in a claim or specification of the present disclosure.

Such programs (software modules, software) include random access memory, non-volatile memory including flash memory, read only memory (ROM), electrically erasable programmable ROM (electrically erasable programmable read only memory, EEPROM), magnetic disc storage device, compact disc-ROM (CD-ROM), digital versatile discs (DVDs), or other It may be stored in an optical storage device or a magnetic cassette. Alternatively, it may be stored in a memory composed of a combination of some or all thereof. In addition, each configuration memory may be included in plurality.

In addition, the program is transmitted through a communication network consisting of a communication network such as the Internet, an intranet, a local area network (LAN), a wide area network (WAN), or a storage area network (SAN), or a combination thereof. It may be stored on an attachable storage device that can be accessed. Such a storage device may be connected to a device implementing an embodiment of the present disclosure through an external port. In addition, a separate storage device on the communication network may be connected to the device implementing the embodiment of the present disclosure.

In the specific embodiments of the present disclosure described above, elements included in the disclosure are expressed in the singular or plural according to the specific embodiments presented. However, the singular or plural expression is appropriately selected for the context presented for convenience of description, and the present disclosure is not limited to the singular or plural component, and even if the component is expressed in plural, it is composed of the singular or singular. Even an expressed component may be composed of a plurality of components.

Meanwhile, although specific embodiments have been described in the detailed description of the present disclosure, various modifications are possible without departing from the scope of the present disclosure. Therefore, the scope of the present disclosure should not be limited to the described embodiments and should be defined by the claims described below as well as the claims and equivalents.

Claims (12)

receiving a double pulse signal from the radar;
generating a binarized first double pulse output signal by comparing the double pulse signal with a first reference voltage through a first voltage comparator;
generating a second binarized double pulse output signal based on the double pulse signal and a second reference voltage through a second voltage comparator;
detecting, through a controller, rising edges of the first double pulse output signal and the second double pulse output signal;
performing, through the controller, pulse decoding based on a time difference value between the rising edges and a preset threshold period; and
and transmitting a response pulse to the radar based on whether the pulse decoding is successful.
The method according to claim 1,
The method of operating a transponder wherein the double pulse signal is input to each of the first voltage comparator and the second voltage comparator.
The method according to claim 1,
The level of the first reference voltage is set to be smaller than the voltage level of the interference signal due to propagation delay,
The second reference voltage is set to be larger than the voltage of the interference signal due to propagation delay of the signal.
The method according to claim 1,
The step of detecting rising edges of the first double pulse output signal and the second double pulse output signal includes:
A method of operating a transponder comprising the steps of detecting a first rising edge and a second rising edge of the first double pulse output signal, and detecting a third rising edge and a fourth rising edge of the second double pulse output signal.
5. The method of claim 4,
The step of identifying whether the pulse decoding is successful,
measuring a first time difference value between the first rising edge and the second rising edge;
identifying whether the first time difference value is included in the threshold interval;
measuring a second time difference value between the third rising edge and the fourth rising edge;
identifying whether the second time difference value is included in the threshold interval; and
and identifying that the pulse decoding is successful when at least one of the first time difference value and the second time difference value is identified as being included in the preset threshold section.
5. The method according to claim 4,
The step of identifying whether the pulse decoding is successful,
Method of operating a transponder comprising the step of identifying that the pulse decoding is successful when at least one of the second rising edge and the fourth rising edge is detected within a time corresponding to the threshold section from the first rising edge .
a receiver for receiving a double pulse signal from the radar;
a first voltage comparator comparing the double pulse signal with a first reference voltage to generate a first double pulse output signal;
a second voltage comparator comparing the double pulse signal with a second reference voltage to generate a second double pulse output signal;
A controller that detects rising edges of the first double pulse output signal and the second double pulse output signal, and performs pulse decoding based on a time difference value between the rising edges and a preset threshold period ; and
and a transmitter for transmitting a response pulse to the radar based on whether the pulse decoding is successful.
8. The method of claim 7,
The double pulse signal is input to each of the first voltage comparator and the second voltage comparator.
8. The method of claim 7,
The level of the first reference voltage is set to be smaller than the voltage level of the interference signal due to propagation delay,
The level of the second reference voltage is set to be greater than the voltage level of the interference signal due to propagation delay of the signal.
8. The method of claim 7,
The controller is configured to detect a first rising edge and a second rising edge of the first double pulse output signal, and a transponder configured to detect a third rising edge and a fourth rising edge of the second double pulse output signal.
11. The method of claim 10,
The controller measures a first time difference value between the first rising edge and the second rising edge,
Identifies whether the first time difference value is included in the threshold interval,
Measuring a second time difference value between the third rising edge and the fourth rising edge,
Identifies whether the second time difference value is included in the threshold interval,
A transponder for identifying that the pulse decoding is successful when at least one of the first time difference value and the second time difference value is identified as being included in the preset threshold section.
11. The method of claim 10,
The controller identifies that the pulse decoding is successful when at least one of the second rising edge and the fourth rising edge is detected within a time corresponding to the threshold period from the first rising edge.

Images