KR102090789B1 - Simulation signal generator and method for measuring performance of radar receiver - Google Patents

Abstract

Provided are a simulation signal generating apparatus for measuring performance of a radar receiver and a method thereof. The apparatus comprises: a time delay generator in a structure based on a field programmable gate array (FPGA) for receiving a trigger signal related to signal transmission of a radar and outputting the trigger signal after delaying the trigger signal for a predetermined time; and a signal generator in synchronization with the trigger signal input from the time delay generator to output a simulation signal having a preset parameter.

Description

Simulated signal generator and method for measuring performance of radar receiver

The present invention relates to a radar, and more specifically, to a simulated signal generating apparatus and method for measuring the performance of a radar receiver.

Radar is a technology that transmits electromagnetic waves to receive information reflected from the target and obtains the target information. Radar is used as the main sensor for the implementation of Advanced Driver Assistance System (ADAS) and Intelligent Transport Systems (ITS), and in addition, it is used as a sensor in various fields that require motion detection, speed, direction, and distance measurement. The radar uses high frequencies such as 24 GHz and 77 GHz, and the high frequency radar has an advantage of improving performance and reducing antenna size.

A frequency modulated continuous wave (FMCW) radar transmits a chirp signal modulated with a frequency sweep shape into a sawtooth wave, a triangular wave, and a trapezoid shape, and processes the received signal reflected by the object as a digital signal. Unlike the Doppler radar, which can only detect speed, the FMCW radar can detect the distance and speed of an object by analyzing the received signal after modulating and transmitting the signal.

The main parameters that determine FMCW radar performance include transmit power (Tx power), bandwidth (Band width), modulation time (sweep time), and transmit frequency (Tx frequency). When mass-producing FMCW radar, transmission parameters can be easily measured using a spectrum analyzer. To measure the performance of the receiver, only the time delay parameter and the power attenuation parameter are changed in the same parameter as the transmitted signal.

However, the power attenuation parameter can be changed using an RF attenuator, but in order to change the time delay parameter to create a time delay signal, the distance between the radar and the reflector is adjusted, the length of the RF cable is adjusted, and the digital delay generator is used. Application must be made.

Therefore, in order to measure the performance of the receiver, a lot of test space for distance adjustment, length adjustment, and application of a digital delay generator is required. In addition, since the receiver performance must be tested while changing the cable length, the test work is cumbersome and the test considering various situations is not efficiently performed. In addition, since the digital delay generator is expensive, there is a disadvantage in that the cost of measuring radar performance is increased.

The problem to be solved by the present invention is to provide an apparatus and method for generating a simulated signal that can more easily and accurately measure the performance of a radar receiver.

The device according to an embodiment of the present invention is a device that generates a simulated signal for measuring the reception performance of a radar, receives a trigger signal related to signal transmission of the radar, and delays the trigger signal for a preset trigger delay time. A time delay generator based on a field programmable gate array (FPGA) based on output; And a signal generator outputting a simulation signal having a preset parameter in synchronization with the trigger signal inputted from the time delay generator.

In one implementation example, the time delay generator may include a buffer chain part including a plurality of look up tables (LUTs) for delaying and outputting the trigger signal during the trigger delay time. Each LUT is configured to output the trigger signal input through one port of a plurality of input ports after a set time delay, and the number of LUTs through which the trigger signal passes may vary according to the trigger delay time.

In one implementation, the time delay generator may further include an LUT selection output unit for selecting and outputting a signal output from a predetermined LUT corresponding to the trigger delay time among the plurality of LUTs. The LUT selection output unit may include an external interface that receives the trigger delay time from the outside.

In one embodiment, the plurality of LUTs are connected in a form that can receive signals output from the previous LUT as inputs and output them to the next LUT. The total delay time in which the trigger signal is delayed by the time delay generator satisfies T _{total_delay} = T _LUT × N _LUT , T _{total_delay} corresponds to the trigger delay time, and T _LUT is the set time delay by one LUT. Indicated, N _LUT may indicate the number of LUTs through which the trigger signal passes.

In one embodiment, the time delay generator is a counter for counting the input clock signal; And a signal delay output unit configured to output the input trigger signal to the signal generator when the value counted by the counter reaches a counter value corresponding to the trigger delay time, wherein the counter value is the trigger. It can be changed according to the delay time.

In one implementation, the time delay generator includes an oscillator; A phase lock loop (PLL) that processes the signal output from the oscillator and provides it to the counter as the clock signal; And a counter value input unit for inputting the counter value to the counter.

In one implementation example, the trigger signal may be generated by the radar and provided to the time delay generator when the radar starts to modulate a transmission signal in mass production test mode.

In one implementation example, the preset parameter may be related to power, and the signal generator may output a simulated signal having a different power from the power of the signal transmitted by the radar.

In one embodiment, the output of the simulated signal may be set in consideration of a path loss according to a distance compared to a radar reflection amount of an object to be detected.

In one implementation example, the trigger delay time may be set based on Δt, Δt = 2R / C, where C represents the speed of light and R represents the distance of the sensing object.

Method according to another embodiment of the present invention, a method for generating a simulated signal for measuring the reception performance of a radar, when the simulated signal generating device, when a trigger signal related to the signal transmission of the radar is input, the plurality of trigger signals Passing a set number of LUTs corresponding to a preset trigger delay time among LUTs (Look Up Tables); And outputting, by the simulated signal generator, a simulated signal having a preset parameter in synchronization with the trigger signal delayed while passing through the set number of LUTs.

In one implementation, the simulated signal generation apparatus may further include receiving the trigger signal generated by the radar when the radar starts to modulate a transmission signal in a mass production test mode.

In one implementation example, in a state in which the radar is installed in the radio-reflection chamber, the radar may be output from the simulation signal generating device to receive the simulation signal radiated in the radio-reflection chamber. In this case, the method for generating a simulated signal may further include a step in which the simulated signal generating device receives the simulated signal received by the radar and measures the reception performance of the radar based on the input signal. You can.

In one implementation example, in the step of outputting the simulated signal, a simulated signal having a power different from the power of the signal transmitted by the radar may be output.

According to an embodiment, it is possible to accurately and easily control parameters related to time delay and signal strength of a simulated signal for measuring reception performance of a radar.

Conventionally, a time delay is generated through physical distance adjustment, but according to an embodiment of the present invention, a simulation signal to which a time delay is applied may be generated using an FPGA-based time delay generator. As a result, it is possible to reduce the size of the device for measuring performance, and to reduce the measurement time by easily changing parameters.

In addition, according to an embodiment, compared to a conventional measurement method requiring physically changing the length of a cable or changing the RF attenuator, the radar of the radar is easily and accurately adjusted by simply changing the counter value input to the time delay generator. Reception performance can be measured.

Further, according to an embodiment, it is possible to easily measure the reception performance of the radar while accurately adjusting the signal strength of the simulated signal by changing the setting of the parameter of the simulated signal output from the RF signal generator.

1 is a view showing the operating characteristics of the FMCW radar.
2 is a view showing the structure of the FMCW radar.
3 is a diagram illustrating an example of measuring transmission parameters using a frequency analyzer.
4 and 5 are diagrams showing an example of measuring the reception performance of a radar.
6 is a diagram showing the structure of a simulated signal generator according to an embodiment of the present invention.
7 is a view showing the structure of a time delay generator according to a first embodiment of the present invention.
8 is a view showing the structure of a time delay generator according to a second embodiment of the present invention.
9 is a flowchart of a method for generating a simulated signal according to an embodiment of the present invention.
10 is an exemplary view showing a timing of a trigger signal according to an embodiment of the present invention.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art to which the present invention pertains may easily practice. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. In addition, in order to clearly describe the present invention in the drawings, parts irrelevant to the description are omitted, and like reference numerals are assigned to similar parts throughout the specification.

Throughout the specification, when a part “includes” a certain component, it means that the component may further include other components, not to exclude other components, unless otherwise stated. In addition, terms such as “… unit”, “… group”, and “module” described in the specification mean a unit that processes at least one function or operation, which may be implemented by hardware or software or a combination of hardware and software. have.

In this specification, expressions expressed in singular may be interpreted as singular or plural unless explicit expressions such as “one” or “single” are used.

Further, terms including ordinal numbers such as first and second used in the embodiment of the present invention may be used to describe elements, but the elements should not be limited by terms. The terms are used only to distinguish one component from another component. For example, the first component may be referred to as a second component without departing from the scope of the present invention, and similarly, the second component may also be referred to as a first component.

Hereinafter, an apparatus and method for generating a simulated signal for measuring the performance of a radar receiver according to an embodiment of the present invention will be described with reference to the drawings.

1 is a view showing the operating characteristics of the FMCW radar.

The FMCW (Frequency Modulated Continuous Wave) radar modulates a signal and transmits it to a target, that is, a sensing object, and receives a signal that is reflected and incident from the sensing object. In addition, as shown in FIG. 1, a time delay according to the distance of the sensing object is acquired using the transmission signal and the reception signal, and the distance and speed of the sensing object are detected using the obtained time delay.

2 is a view showing the structure of the FMCW radar.

In the FMCW radar, the ramp signal is controlled by an oscillator, amplified by a power amplifier, and then transmitted through an antenna to a target, as shown in FIG. 2 (a). The signal reflected by the sensing object is received by the antenna. An IF signal is obtained as the received signal passes through a low-noise amplifier and is multiplied by a transmission signal in a frequency mixer, i.e., a mixer, and then output through an IF (Intermediate Frequency) amplifier. The IF signal is converted to a digital signal through an analog to digital converter (ADC). Based on these signals, as shown in FIG. 2B, the distance and speed of the sensing object can be known.

The main parameters that determine the performance of the FMCW radar operating in this way include transmission power (Tx power), bandwidth (Band width), modulation time (sweep time), and transmission frequency (Tx frequency).

3 is a diagram illustrating an example of measuring transmission parameters using a frequency analyzer.

When mass-producing the FMCW radar, as illustrated in FIG. 3, the radar is placed in a radio-reflection chamber to transmit a signal, and a transmission signal propagated in the radio-reflection chamber is received by an antenna and input to a frequency analyzer (Spectrum Analyzer) do. Based on the analysis result of the frequency analyzer, transmission parameters related to the transmission signal, for example, frequency, transmission power, and bandwidth, can be measured.

On the other hand, when measuring the reception performance of the radar, that is, the performance of the receiver, for a signal for measuring the performance of the receiver, a time delay in the same parameter as the transmitted signal (time delay, where time delay is proportional to the distance from the sensing object) Only parameters and power attenuation (where power attenuation is related to the amount and distance of the sensing object).

4 and 5 are diagrams showing an example of measuring the reception performance of a radar.

An RF attenuator is used to change the power attenuation parameter, and changing the time delay parameter requires adjusting the distance between the radar and the reflector.

For example, as illustrated in FIG. 4, the radar to be tested is operated through the control of the radar PC to transmit a signal, and the radar then receives a signal reflected by a sensing object, that is, a reflector, and the control PC The signal received by the radar is read through a signal processing circuit, and the reception performance of the radar is measured based on the read signal. The reception performance measurement process is repeatedly performed while changing the distance between the reflector and the radar, and the time delay parameter for measuring reception performance is changed according to the change in the distance between the reflector and the radar.

In this case, since the time delay parameter must be changed by performing a process of physically changing the distance between the reflector and the radar (object B, the distance to the object C, etc.), accurate time delay parameter changes are not made, and the physical distance It is required to secure a test space for adjustment and the distance adjustment process is cumbersome.

Meanwhile, the reception performance of the radar can be measured by changing the time delay parameter using an RF cable. For example, as illustrated in FIG. 5, upon mass production of the FMCW radar, the radar is placed in a radio-reflection chamber, and a transmission signal output from the radar and propagated in the radio-reflection chamber is received by the antenna, and then to the antenna. It passes through the RF cable to create a connected time delay. As the signal passes through the RF cable for time delay generation, the time delay and power attenuation signal is radiated again through another antenna connected to the RF cable. Thereafter, a signal radiated into the radio-reflective chamber through the other antenna is received by the radar, and performance measurement is performed based on the received signal.

In this case, since the time delay parameter is changed through adjusting the physical length of the RF cable, it is necessary to replace the RF cable having a different length every time the time delay parameter is changed, and the exact time delay parameter change is not made.

As described above, in order to measure the performance of a radar receiver, a test space for adjusting the distance to an object to be detected and adjusting the cable length is required, which increases the size of the performance measurement device. In addition, since it is necessary to perform the performance test of the receiver while repeatedly adjusting the distance between the object and the radar or changing the cable length, it is not easy to set quantitative parameters for the test, and the test process is cumbersome and the time required is increased.

In an embodiment of the present invention, by using a RF signal generator (Signal Generator) and a field programmable gate array (FPGA) to quantitatively control parameters for receiving performance measurement (eg, power attenuation parameter and time delay parameter), radar Generate a simulated signal to measure the performance of the receiver.

6 is a diagram showing the structure of a simulated signal generator according to an embodiment of the present invention.

The simulated signal generator 1 according to an embodiment of the present invention, as shown in FIG. 6 attached, according to the input trigger signal, RF signal for measuring the performance of the receiver of the radar 2 to be tested (simulated RF signal generator 11 to generate a signal), and outputs a trigger signal to the RF signal generator 11, and applies a time delay to the trigger signal to generate a time delay for the RF signal (12) ), And a signal meter 13 for measuring the reception performance of the time-delayed RF signal based on the signal received by the radar 2.

The radar 2 to be tested is located in the radio-reflection chamber 3, and the signal output from the RF signal generator 11 is radiated by the antenna 31 in the radio-reflection chamber 3 by an RF cable. It is received by the radar 2. Here, it is preferable that the RF cable connecting the antenna 31 and the RF signal generator 11 has the smallest possible length. This is to minimize the effect of time delay and signal loss due to the RF cable.

The radar 2 generates and outputs a trigger signal. For example, the radar 2 may generate a trigger signal at the start of modulation of the transmission signal.

The time delay generator 12 delays the input trigger signal for a predetermined time, and then transmits the delayed trigger signal to the RF signal generator 11.

The trigger signal output from the time delay generator 12 is input to the RF signal generator 11, for example, to a trigger input port of the RF signal generator 11. Here, the trigger input port represents a port set for trigger signal input among at least one input port of the RF signal generator 11.

The RF signal generator 11 outputs an RF signal that is a simulated signal when a trigger signal is input. The RF signal generator 11 outputs an RF signal in synchronization with a trigger signal delayed by the time delay generator 12, so that an RF signal to which time delay is applied by the time delay generator 12 is output.

Looking at the specific structure of the time delay generator 12 to delay the trigger signal is as follows.

 When the trigger signal is input, the time delay generator 12 according to an embodiment of the present invention outputs a corresponding trigger signal after a preset time, and may be formed in a designable FPGA-based structure. Hereinafter, for convenience of description, the preset time is referred to as a “trigger delay time”.

7 is a view showing the structure of a time delay generator according to a first embodiment of the present invention.

The time delay generator 12 according to the first embodiment of the present invention includes a counter 121 and a signal delay output unit 122 as shown in the attached FIG. 7, and in addition, a clock signal generation unit 123 , An oscillator 124 and a counter value input unit 125 may be further included.

The counter 121 performs counting according to the input clock signal and transmits the counted value to the signal delay output unit 122.

When the value counted by the counter 121 reaches a preset counter value, the signal delay output unit 122 transmits the trigger signal input from the radar 2 to the RF signal generator 11.

The counter value corresponds to a preset time, that is, a trigger delay time, and may be set and changed according to a value input by the counter value input unit 125. Through the change of the counter value, a time delay in a process in which a trigger signal input from the radar 2 is transmitted to the RF signal generator 11 may be changed, and for measuring a reception performance of the radar in synchronization with the time delayed trigger signal. RF signal is output. Therefore, according to the first embodiment of the present invention, it is possible to easily and quantitatively control the time delay parameter for measuring the performance of the radar receiver.

Meanwhile, the counter 121 may count signals output from the oscillator 124. For example, the counter 121 may detect and count a rising edge of a signal output from the oscillator 124 from a low level to a high level. The invention is not limited to this. Here, by using a signal input from the external oscillator 124, it is possible to maintain the same performance in environmental changes.

Also, a clock signal generator 123 may be included between the counter 121 and the oscillator 124. The clock signal generation unit 123 processes the signal output from the oscillator 124 and outputs a clock signal having a predetermined frequency to the counter 121.

The clock signal generator 123 may be formed of a phase lock loop (PLL). In this case, for example, the clock signal generator 123 may output a 1 GHz clock signal using a PLL. The counter 121 performs a count according to the 1 GHz clock signal, and the trigger delay time (counter value) is transmitted to the RF signal generator 11 after the trigger delay time (counter value) according to the value at which the signal delay output unit 122 is counted. Time delay generation in units becomes possible. In synchronization with the trigger signal to which the time delay is applied, the RF signal generator 11 outputs an RF signal, that is, a simulated signal, thereby generating a signal capable of simulating the distance between the radar 2 and the sensing object in units of 0.15 m.

In addition, in the embodiment of the present invention, the structure of the time delay generator 12 may be implemented differently.

8 is a view showing the structure of a time delay generator according to a second embodiment of the present invention.

The time delay generator 12 'according to the second embodiment of the present invention includes a buffer chain section 126, as shown in the attached FIG. 8, and in addition, the LUT selection output section 127 It may further include.

The buffer chain unit 126 outputs an input trigger signal after a trigger delay time, and includes a plurality of look up tables (LUTs) for this. Specifically, as shown in Figure 8, and includes N (where, N is a positive integer) of LUT (126_ 126_ L 1 ~ L N). Each LUT has a plurality of input ports, that is, M (where M is a positive integer, for example, M = 4) input ports, and receives a signal input through one of the plurality of input ports. After the set time delay, output through the output port. Here, the LUT has one output port, but is not limited thereto.

As the N LUT (126_ 126_ L 1 ~ L N) are shown in Figure 8, it receives the signal output from the LUT before the input is connected to a form that can be output to the next LUT. The set time delay occurs each time one LUT passes, and thus the time delay of the signal input to the buffer chain unit 126 varies according to the number of LUTs through which the signal passes.

For example, one LUT has 4 input ports and 1 output port, as shown in FIG. 8, and outputs a signal input through one input port among 4 input ports through one output port. , Has a set time delay of 0.5ns. Based on these LUTs, a total time delay of at least 0.5 ns to tens of ns or hundreds of ns can be obtained. For example, when the buffer chain 126 is composed of 10000 LUTs, a total time delay of up to 5000 ns (5 μs) can be obtained. In this case, if the trigger delay time to delay the trigger signal is 100 ns, the trigger signal is output after passing 200 LUTs out of 10000 LUTs of the buffer chain section 126. Therefore, the total delay time of the trigger signal through the buffer chain unit 126 satisfies T _{total_delay} = T _LUT × N _LUT , where T _{total_delay} corresponds to the trigger delay time, and T _LUT is the time by one LUT Denotes delay, and N _LUT represents the number of LUTs through which the trigger signal passes. Therefore, the delay time of the trigger signal can be changed by adjusting the number of LUTs through which the trigger signal passes.

Meanwhile, the LUT selection output unit 127 selects and outputs a signal output from a predetermined LUT of the buffer chain unit 126 according to a trigger delay time to delay the trigger signal. The LUT selection output unit 127 may be configured as a multiplexer (MUX). Specifically, a plurality of input terminals of the LUT selection output unit 127 are connected to the output ports of each LUT of the buffer chain unit 126. An input terminal connected to an output port of a predetermined LUT is selected according to a trigger delay time, and an output signal of the LUT input through the input terminal is output as a delayed trigger signal.

The LUT selection output unit 127 includes an external interface 1271 that receives trigger delay time, which is time delay information from the outside, and the external interface 1271 interfaces such as RS-232, Serial Peripheral Interface (SPI), and I2C. Can be

For example, when a trigger delay time of 100 nS is input through the external interface 1271 (for example, the delay per LUT is 0.5 nS delay), the LUT selection output 127 is an input connected to the output port of the 200th LUT The terminal is selected and the output signal of the 200th LUT input through the selected input terminal is output. Therefore, after the trigger signal input to the buffer chain unit 126 passes through 200 LUTs, it is output as a delayed trigger signal through the LUT selection output unit 127.

As described above, while the trigger signal passes through the set number of LUTs, the time delay in the process of transmitting the trigger signal to the RF signal generator 11 may vary, and the RF signal for measuring the reception performance of the radar in synchronization with the time delayed trigger signal Is output. Therefore, according to the second embodiment of the present invention, it is possible to easily and quantitatively control the time delay parameter for measuring the performance of the radar receiver.

On the other hand, the RF signal generator 11 outputs an RF signal in synchronization with a trigger signal input from the time delay generators 12 and 12 'having the above structure, and in particular, can output an RF signal having a preset parameter. have. That is, whenever a trigger signal is input from the outside, an RF signal having a preset parameter is output. Here, the parameter may be a parameter related to frequency, bandwidth, sweep time, power size, and the like.

In one implementation example, the parameter of the RF signal output in synchronization with the trigger signal input may be a parameter having the same characteristics as the parameter of the transmission signal of the radar 2. In another implementation example, the parameter of the RF signal output in synchronization with the trigger signal input may have a parameter identical to that of the transmission signal of the radar 2 and only some of the characteristics may be different. For example, the parameter of the RF signal may be a parameter having the same frequency and bandwidth as the transmission signal of the radar 2 and a power size different from that of the transmission signal. For example, the parameter of the RF signal may be a power attenuation parameter that causes the power size of the RF signal to be smaller than the power size of the transmission signal.

In another implementation, RF signals of the same parameter may be output each time a trigger signal is input, or RF signals of different parameters may be output. For example, different parameters are set in advance, and whenever a trigger signal is input, an RF signal having a parameter in the order may be output in a preset order.

As described above, since parameters of an RF signal output in synchronization with a trigger signal can be set and changed, according to an embodiment of the present invention, parameters for measuring performance of a radar receiver, for example, power attenuation parameters can be easily performed. It can be controlled politically.

On the other hand, the RF signal output from the RF signal generator 11 is transmitted to the antenna 31 in the radio-reflection chamber 3 through an RF cable, and then radiated by the antenna 31 and then received by the radar 2 do.

The signal meter 13 measures the reception performance based on the signal received by the radar 2. At this time, as described above, a time delay parameter is applied according to the trigger signal, and an RF signal to which a power attenuation parameter is applied can be received, and the performance of the receiver of the radar 2 is measured based on the received signal. You can. As a method for measuring the performance, a technique known in the art can be used, so a detailed description is omitted here.

Next, a description will be given of a method for generating a simulated signal for measuring the reception performance of a radar according to an embodiment of the present invention using a simulated signal generating device with such a structure.

9 is a flowchart of a method for generating a simulated signal according to an embodiment of the present invention.

When the radar 2 to be tested is mounted on a mass production jig (not shown) of the radio-reflective chamber 3, the radar 2 enters a mass production test mode rather than a normal operation mode. For example, the radar 2 has a mass input test mode when a pin input signal (for example, a high or low level signal) connected to a mass production jig (not shown) is a set level signal. Can enter.

In mass production test mode, the radar 2 turns off the transmission signal. In order to accurately measure the performance of the receiver of the radar 2 without interference, in the embodiment of the present invention, the transmission signal of the radar 2 is turned off in the mass production test mode, but is not limited thereto.

In the mass production test mode, the radar 2 outputs a trigger signal to the time delay generator 12 as shown in FIG. 9 (S100, S110). Specifically, the radar 2 generates a trigger signal at the start of modulation of the transmission signal, and transmits it to the time delay generator 12 or 12 'of the simulated signal generator 1 according to an embodiment of the present invention.

When the trigger signal is input, the time delay generator 12 or 12 'of the simulated signal generator 1 according to an embodiment of the present invention transmits the trigger signal to the RF signal generator 11. In this case, the time delay generator 12 or 12 'transmits the trigger signal to the RF signal generator 11 after a preset time after the trigger signal is input (S120). Here, the preset time corresponds to a trigger delay time to delay the trigger signal, and as described above, the counter value is changed according to the trigger delay time or the number of LUTs through which the trigger signal is changed is time delay. The time at which the trigger signal input to the generator 12 or 12 'is delayed may be changed. In the case of the time delay generator 12 'in which the number of LUTs through which the trigger signal passes according to the trigger delay time is changed, in step S120, the trigger signal has a set number of LUTs corresponding to the trigger delay time among the plurality of LUTs. Delay by passing through. The detailed description refers to what has been described above, and is not repeated herein.

When the trigger signal to which the time delay is applied by the time delay generator 12 or 12 'is input to the RF signal generator 11, the RF signal generator 11 synchronizes with the input trigger signal, that is, an RF signal of a preset parameter, that is, Simulate signals are output (S130, S140). As described above, the simulated signal output from the RF signal generator 11 according to the trigger signal input from the outside is transmitted to the antenna 31 through the RF cable and radiated (S150).

The simulated signal emitted by the antenna 31 is received by the radar 2 located in the radio-reflective chamber 3, that is, received by the receiver of the radar 2 (S160), and the received signal is a signal meter ( 13) is transmitted to (S170). Thereafter, the signal meter 13 analyzes the received signal to measure and determine the performance of the receiver of the radar 2 (S180).

In the method and apparatus for generating a simulated signal according to an embodiment of the present invention as described above, the timing of the trigger signal is specifically illustrated in FIG. 10.

10 is an exemplary view showing a timing of a trigger signal according to an embodiment of the present invention.

In the radar in mass production test mode, at the start of modulation of the transmission signal as in Fig. 10 (a), a trigger signal is output from the radar as in Fig. 10 (b). The trigger signal output from the radar is delayed by the transmission / reception time delay time (trigger delay time) as shown in FIG. 10 (c) by the time delay generator. Thereafter, an RF signal of a parameter preset by the RF signal generator according to the delayed trigger signal, that is, a simulated signal is output.

The transmission / reception time delay time corresponding to the trigger delay time may be set based on Δt, Δt = 2R / C, where C represents the speed of light and R represents the distance of the sensing object. For example, when simulating a signal reflected from a sensing object at a distance of 3 m from the radar, the transmission / reception time delay time is about 20 ns. When simulating a signal reflected from a sensing object at a distance of 30 m from the radar, the transmission / reception time delay time is simulated. Is about 200ns.

The RF signal of the RF signal generator 13 output according to the transmission / reception time delay time (trigger delay time), that is, the output of the simulated signal, considers path loss according to the distance to the radar reflection amount of the object to be detected. Can be set.

)은 다음과 같이 나타낼 수 있다. The output of the signal reflected by the simulated signal and received by the radar (

) Can be represented as

은 수신 전력(Receive Power)이다. 이러한

은 송신 신호의 출력을 임의 값으로 설정하여 전송하였을 때 해당 거리 및 RCS에 반사되어 돌아오는 수신 전력 크기를 나타낸다.

는 송신 신호의 출력(단위는 와트(watt))을 나타내며, G 는 안테나 이득을 나타내고,

는 모사 신호의 파장(단위는 미터(meter))을 나타낸다. R은 감지 물체의 거리(단위는 미터)를 나타내고,

는 RCS(m²)를 나타낸다. RCS(Radar cross section)는 물체 표면이 가지는 전파 반사량으로, 레이더가 보는 반사 면적 크기를 나타낸다. 예를 들어, 감지 물체가 인체인 경우, 성인 기준 RCS는 약 1m²이다. here,

Is the Receive Power. Such

Denotes the distance and the amount of received power reflected back to the RCS when the output of the transmission signal is set to an arbitrary value and transmitted.

Is the output of the transmission signal (unit is watts), G is the antenna gain,

Denotes the wavelength (in meters) of the simulated signal. R represents the distance (in meters) of the sensing object,

Represents RCS (m ² ). The radar cross section (RCS) is the amount of radio wave reflection on the surface of an object and indicates the size of the reflection area seen by the radar. For example, if the sensing object is a human body, the adult reference RCS is about 1 m ² .

(파장, 빛의 속도/주파수)는 0.0125m인 것으로 가정한다. 그리고, 감지 물체가 인체 1이며,

는 RCS(인체1=1m²)인 경우, 위의 수학식 1에 따라

은 다음과 같이 계산된다. For example, if the sensing distance is 10m, the output of the transmission signal is 20dBm (0.1 watt), G is 100 ((100 times for a 20dB antenna),

(Wavelength, speed / frequency of light) is assumed to be 0.0125m. And, the sensing object is the human body 1,

Is RCS (Human 1 = 1 m ² ), according to Equation 1 above

Is calculated as follows.

Therefore, when measuring the performance of a radar receiver based on a signal reflected from a human body at a distance of 10 m (trigger delay time for generating a simulated signal is, for example, 33 ns), reception of a simulated signal generated according to an embodiment of the present invention The power is set to about -51 dBm considering the path loss according to the distance compared to the radar reflection amount of the object according to the FSPL (Free Space pass loss). FSPL indicates the degree of reduction in radar output in an empty space without obstacles.

According to an embodiment of the present invention as described above, it is possible to accurately and easily control parameters such as time delay and signal strength of a simulated signal for measuring the performance of a radar receiver. In the past, a time delay was generated with a physical distance, but a simulated signal can be generated using an FPGA-based time delay generator according to an embodiment of the present invention, thereby reducing the size of a device for measuring performance and miniaturization. It is easy to change, which can shorten the measurement time.

The embodiment of the present invention is not implemented only through the apparatus and / or method described above, and is implemented through a program for realizing a function corresponding to the configuration of the embodiment of the present invention, a recording medium in which the program is recorded, and the like. Alternatively, such an implementation can be easily implemented by those skilled in the art to which the present invention pertains from the description of the above-described embodiments.

Although the embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto, and various modifications and improvements of those skilled in the art using the basic concept of the present invention defined in the following claims are also provided. It belongs to the scope of rights.

Claims (14)

A device that generates a simulated signal for measuring reception performance of a frequency modulated continuous wave (FMCW) radar,
A field programmable gate array (FPGA) -based time delay generator for receiving a trigger signal related to signal transmission of the radar and outputting after delaying the trigger signal for a preset trigger delay time; And
A signal outputting a simulated signal in synchronization with the trigger signal input from the time delay generator, wherein the simulated signal has power different from that of a signal transmitted by the radar while power is controlled according to a preset parameter. Generator
Including,
The time delay generator includes a buffer chain part including a plurality of look up tables (LUTs) for delaying and outputting the trigger signal during the trigger delay time,
The total delay time in which the trigger signal is delayed by the time delay generator satisfies T _{total_delay} = T _LUT × N _LUT , T _{total_delay} corresponds to the trigger delay time, and T _LUT is the set time delay by one LUT. N _LUT represents the number of LUTs through which the trigger signal passes, and a simulated signal generating device. According to claim 1,
Each LUT is configured to output the trigger signal inputted through one of the plurality of input ports after a set time delay, and the plurality of LUTs can receive signals output from the previous LUT as inputs and output them to the next LUT. A simulated signal generating device connected in a form. According to claim 2,
The time delay generator
LUT selection output unit for selecting and outputting a signal output from a predetermined LUT corresponding to the trigger delay time among the plurality of LUTs
Further comprising,
The LUT selection output unit includes an external interface that receives the trigger delay time from the outside, a simulated signal generating device. delete delete delete The method according to any one of claims 1 to 3,
The trigger signal is generated by the radar when the radar starts to modulate a transmission signal in a mass production test mode and is provided to the time delay generator, a simulated signal generator. delete The method according to any one of claims 1 to 3,
The output of the simulated signal is set in consideration of a path loss according to a distance to a radar reflection amount of an object to be detected, a simulated signal generating device. The method according to any one of claims 1 to 3,
The trigger delay time is set based on Δt, Δt = 2R / C, where C represents the speed of light and R represents the distance of the sensing object. As a method of generating a simulated signal for measuring the reception performance of the FMCW (Frequency Modulated Continuous Wave) radar,
When the simulated signal generating apparatus, when a trigger signal related to signal transmission of the radar is input, passing the trigger signal through a set number of LUTs corresponding to a preset trigger delay time among a plurality of look up tables (LUTs); And
The simulated signal generating device, in synchronization with the trigger signal delayed while passing through the set number of LUTs, is a simulated signal-the simulated signal is controlled by power according to a preset parameter and is different from the power of the signal transmitted by the radar. Having different power-outputting
It includes,
The total delay time in which the trigger signal is delayed satisfies T _{total_delay} = T _LUT × N _LUT , T _{total_delay} corresponds to the trigger delay time, T _LUT represents a set time delay by one LUT, and N _LUT is A method of generating a simulated signal indicating the number of LUTs through which the trigger signal is passed. The method of claim 11,
Receiving, by the simulated signal generator, the trigger signal generated by the radar when the radar starts modulating a transmission signal in mass production test mode.
Method for generating a simulated signal further comprising a. The method of claim 11,
In the state in which the radar is installed in the radio-reflection chamber, the radar is output from the simulation signal generating device and receives the simulation signal radiated in the radio-reflection chamber,
The method for generating a simulated signal,
The apparatus for generating a simulated signal, receiving the simulated signal received by the radar, and measuring the reception performance of the radar based on the input signal
Method for generating a simulated signal further comprising a. delete

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