JP3433708B2 - Signal receiving / processing apparatus for search and rescue radar transponder and signal receiving / processing method - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a search and rescue radar transponder signal receiving and processing apparatus suitable for receiving and processing SART (search and rescue radar transponder) in SAR (synthetic aperture radar) and its signal receiving and processing. Regarding the method.

[0002]

2. Description of the Related Art SAR (Synthetic Aperture Radar) is a type of image radar. SAR (Synthetic Aperture Radar) has a higher resolution than other radars, and unlike optical sensors, it can be used under all weather conditions, and is therefore mainly used for earth observation (remote sensing).

Such a system using SAR (Synthetic Aperture Radar) was initially used in the field of satellite remote sensing, but in recent years, due to the weatherability and high resolution of SAR (Synthetic Aperture Radar). , Is required to be used in the field of marine search.

To meet this demand, for example, FIG.
As shown in (1), it is necessary to detect and display a signal transmitted by a SART (search and rescue radar transponder) with a radar, together with the discovery of a distressed ship by visualization of the sea surface.

The SART is, as shown in FIG.
When one wave between 9.2 GHz and 9.5 GHz is received once, 7.5 μsec between 9.2 GHz and 9.5 GHz is received.
Sweep with. One response transmission is characterized by repeating this 12 times. Here, FIG. 8A shows radio waves from the radar, and FIG. 8B shows SART transmission radio waves.

Therefore, when a navigation radar (having a narrow transmission frequency band within 9.2 GHz to 9.5 GHz) mounted on a ship captures the SART signal,
As shown in (b), the SART signal is displayed as a 12-point display. It should be noted that FIG. 9A shows a reception state in the navigation radar.

By the way, in a conventional SAR (Synthetic Aperture Radar), a transmitted wave having a spectrum shown in (2) of FIG. 4A is followed according to a chirp wave shown in (1) of FIG. , Depending on the intensity of the reflected wave from the sea surface or other objects, as shown in (3) of FIG.
The transmitted signal may be buried under the reflected SAR received signal.

In this case, as shown in FIG. 10, a radar other than a synthetic aperture radar used for marine search, such as a search radar, has a frequency different from that of the search radar received signal and is a SART reception window for SART. By providing the reception window, it is possible to reduce the influence that the SART transmission signal cannot be received due to the reflected wave from the sea surface or another object.

[0009]

However, the above-mentioned conventional method is effective for a radar having a narrow transmission frequency band, but the SAR has a wide band of about 100 MHz.
(Synthetic aperture radar) requires a dedicated device for SART reception. Moreover, without using such a dedicated device, S
In order to receive the ART signal, it is necessary to drastically change the existing SAR (Synthetic Aperture Radar) system.

The present invention has been made in view of such circumstances, and ensures reception and display of a SART (search and rescue radar transponder) signal without requiring a drastic change in SAR (synthetic aperture radar). (EN) A signal receiving / processing device for a search and rescue radar transponder and a signal receiving / processing method therefor.

[0011]

[Means for Solving the Problems]Of the present inventionSearch and rescue leh
The signal receiving / processing device of the da transponder is located outside the ground.
Send a transmission wave to irradiate the target of the department,
Receives the reflected wave from the target or the received reflected wave
After adding signal processing to the received complex data to
SAR transmission / reception that outputs I and Q components of complex data
I component of received complex data from the receiver and SAR transceiver
SAR processing is applied to each of the Q and Q component signals.
The SAR processing unit that outputs the SAR image real number signal, and
From the I and Q components of the complex data
Performs SART signal extraction processing and outputs SART real number signals
SART processing unit, SAR image real number signal and SAR
After receiving the T real number signal, the
Convert to a display signal in a format that can be played and display
Image display section to be displayed onPreparation, and further SART
The processing unit converts the I and Q components of the received complex data into complex
Fourier transform, I component and Q component of frequency domain complex signal
FFT section for outputting the I component and frequency domain complex signal
And Q component are low-pass filtered to obtain a complex signal
Filter unit for outputting the I and Q components of the complex signal
Performs a complex inverse Fourier transform on the I and Q components of
An IFFT unit for outputting I and Q components of a complex signal,
The power of the I and Q components of the complex signal is converted to SAR.
And a power conversion section for outputting a T real number signal.Characterized by
And In addition, the SAR transceiver unit transmits and reflects the transmitted wave.
The antenna part that receives waves and the transmission and reception of transmitted and reflected waves
A transmission / reception switching unit that performs switching and a channel that generates a chirp wave
And a chirp wave generator that sends the chirp wave to the antenna section.
A synchronization signal that indicates the transmission timing for the transmission unit and the transmission unit.
And to the transmitter and the chirp wave generator,
Signal generation that gives a pulse repetition frequency (PRF)
Section, the reflected wave and the synchronization signal are mixed,
A first mixer for outputting a mixing signal of 1;
The first signal component from which the high frequency component of the mixing signal has been removed
The first LPF to be output and the first signal component are digitally transmitted.
No. 1 that outputs the I component of the received complex data
Outputs a delayed signal that is a delay of the sync signal from the A / D converter
Delay section, and mixing of reflected wave and delayed signal
A second mixer for processing and outputting a second mixing signal.
Mixer and the first high frequency component of the second mixing signal are removed.
A second LPF that outputs a second signal component, and a second signal component
Minute component is converted to a digital signal and the Q component of the received complex data is
Providing a second A / D converter for outputting
You canOf the present inventionSearch and rescue radar transponder
The signal receiving / processing method of the signal receiving / processing device is SAR transmission.
The receiving unit irradiates external targets such as the ground surface.
To receive the reflected wave from the target.
The received complex data is transmitted to the reflected wave received or received.
I and Q of the received complex data
The first step of outputting the components and the reception from the SAR transceiver
For each signal of I component and Q component of the complex data
Then, SAR processing is performed by the SAR processing unit to obtain the SAR image.
The second step of outputting a real number signal and I of the received complex data
To the SART processing unit from the respective signals of the component and the Q component
SART signal extraction processing is performed to obtain the SART real number signal.
Output third step, SAR image real number signal and SAR
After receiving the T real number signal,
Change to a display signal in a format that can be displayed on the signal.
The fourth step of converting and displaying on the displayPrepare,
Further, in the third step, the reception complex data is received by the FFT unit.
Complex I / Q component of the data
Outputting the I and Q components of the domain complex signal,
Filter unit for I and Q components of wavenumber domain complex signal
Low-pass filter processing by
The process of outputting the minute and Q components and the IFFT section
The complex inverse Fourier transform is applied to the I and Q components of the raw signal.
And outputting the I and Q components of the complex signal,
The power conversion unit powers the I and Q components of the complex signal.
And output the SART real number signal.
BeIt is characterized by In the first step, the transmitted wave
The antenna unit transmits and receives reflected wavesProcess
The transmission / reception switching unit switches the transmission / reception of transmitted waves and reflected waves.
DoProcessAnd a chirp wave is generated by the chirp wave generator.
CompleteProcessThe chirp wave is transmitted to the antenna section by the transmitting section.
Send toProcessAnd the synchronization signal generation unit
And give a synchronization signal that indicates the transmission timing,
Pulse repetition frequency for transmitter and chirp generator
Give a number (PRF)ProcessAnd the first mixer
The mixing process of the reflected wave and the synchronization signal is performed, and the first mixing
Output a singing signalProcessAnd the first LPF
The first signal composition from which the high frequency component of the mixing signal of 1 is removed.
Output minutesProcessAnd the first A / D converter causes the first
Of the received complex data by converting the signal component of
Output I componentProcessAnd a delay signal that delays the synchronization signal.
No. 2 by the Delay section, and the second Miki
The mixing process of the reflected wave and the delayed signal is performed by the
Output a second mixing signalProcessAnd the second L
The PF removes the high frequency component of the second mixing signal.
Output the second signal componentProcessAnd the second A / D conversion
Section converts the second signal component into a digital signal and receives it.
Output the Q component of the complex dataProcessTo include and
Can be Search and rescue radar according to the present invention
Responder signal receiving / processing device and its signal receiving / processing
In the processing method, the SAR transmitting / receiving unit
Transmitted a transmission wave to illuminate an external target
Receive the reflected wave from the target or
Added signal processing to the received wave as received complex data
After that, I component and Q component of the received complex data are output, and SA
R component of the complex data received from the transceiver
SAR processing by the SAR processing unit for each signal
To output the SAR image real number signal and receive the complex data
SART processing from each signal of I component and Q component of
SART signal extraction processing is performed by the
Output SAR image real number signal and SART real number signal
After receiving the
Convert it to a display signal in a format that can be displayed on the display, and
SAR transmission / reception by displaying on the spray
Open the window for SART reception in the chirp wave generation unit
Digit transmission pattern is generated and the received complex data
The SART processing unit can receive and process SART.
Become.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below.

FIG. 1 is a block diagram showing an embodiment of a signal receiving / processing device for a search and rescue radar transponder according to the present invention, and FIG. 2 is a block diagram showing details of the SAR transmitting / receiving section of FIG. 1 is a block diagram showing the details of the SART processing unit in FIG. 1. FIG. 4 is a diagram for explaining the operation of the signal receiving / processing device of the search and rescue radar transponder in FIG. 5 is S in FIGS. 1 and 3.
FIG. 6 is a diagram for explaining the operation of the ART processing unit, and FIG.
It is a figure which shows the example of a display of this display.

The signal receiving / processing device of the search and rescue radar transponder shown in FIG. 1 is a SAR (Synthetic Aperture Radar).
The SAR transmission / reception unit 1, the SAR processing unit 2, the SART processing unit 3, the image display unit 4, and the display 5
Is equipped with.

The SAR transmission / reception unit 1 transmits a transmission wave 103 for irradiating an external target such as the surface of the earth, and receives a reflected wave 104 from the target. Also,
The SAR transceiver 1 performs signal processing on the received reflected wave 104 and then outputs the I component 101 and the Q component 102 of the received complex data.

The SAR processing unit 2 performs SAR processing on the respective signals of the I component 101 and the Q component 102 of the received complex data from the SAR transmission / reception unit 1 and outputs a SAR image real number signal 105.

The SART processing unit 3 performs SART signal extraction processing from the respective signals of the I component 101 and the Q component 102 of the complex data received from the SAR transmission / reception unit 1, and outputs the SA signal.
The RT real number signal 106 is output.

The image display unit 4 displays the SAR image real number signal 10
5 and the SART real number signal 106 are received, the displayable format (display signal 1
07) and display it on the display 5.

The details of the SAR transceiver 1 are shown in FIG.

The SAR transmission / reception unit 1 includes an antenna unit 11, a transmission / reception switching unit 12, a transmitter 13, a synchronization signal generation unit 14, a mixer 15, a Delay unit 16, an LPF 17, an A / D conversion unit 18, a mixer 19, an LPF 20, and A. The / D converter 21 is provided.

The antenna section 11 has the transmission wave 103 described above.
And the reflected wave 104 are received. Transmission / reception switching unit 12
Switches between transmission and reception of the transmitted wave 103 and the reflected wave 104. The transmitter 13 includes a transmitter 13a and a chirp wave generator 13b. The transmitter 13a transmits the chirp wave generated by the chirp wave generator 13b.

The synchronization signal generator 14 gives the transmitter 13a a synchronization signal 201 indicating the transmission timing. In addition, the synchronization signal generation unit 14 supplies the pulse repetition frequency (PRF) to the transmission unit 13a and the chirp wave generation unit 13b.
Give 212. The mixer 15 as the first mixer is
The reflected wave 104 and the synchronization signal 201 are mixed, and a mixing signal 20 as a first mixing signal is obtained.
7 is output. The delay unit 16 outputs a delay signal 209 obtained by delaying the synchronization signal 201.

The LPF 17 as the first LPF outputs a signal component 208 as a first signal component obtained by removing the high frequency component of the mixing signal 207 from the mixer 15.
The A / D conversion unit 18 as the first A / D conversion unit
The I component 101 of the received complex data obtained by converting the signal component 208 from F17 into a digital signal is output.

The mixer 19 as the second mixer performs mixing processing of the reflected wave 104 and the delayed signal 209,
The mixing signal 210 as the second mixing signal is output. The LPF 20 as the second LPF outputs a signal component 211 as a second signal component obtained by removing the high frequency component of the mixing signal 210 from the mixer 19. The A / D converter 21 as the second A / D converter is an LPF.
The Q component 102 of the received complex data obtained by converting the signal component 211 from 20 into a digital signal is output.

Details of the SART processing unit 3 are shown in FIG.

The SART processing section 3 comprises an FFT section 31, a filter section 32, an IFFT section 33 and a power conversion section 34.

The FFT unit 31 performs a complex Fourier transform on the I component 101 and the Q component 102 of the received complex data, and outputs the I component 401 and the Q component 402 of the frequency domain complex signal. The filter unit 32 has its I component 401 and Q component 4
02 is subjected to low-pass filter processing, and the complex signal I
The component 403 and the Q component 404 are output.

The IFFT section 33 includes an I component 40 of the complex signal.
Perform a complex inverse Fourier transform on the 3 and Q components 404,
The I component 405 and the Q component 406 of the complex signal are output.
The power conversion unit 34 has an I component 405 and a Q component 406.
To output the SART real number signal 106.

Next, the operation of the signal receiving / processing device of the search and rescue radar transponder having such a configuration will be described.

The operation of the SAR transceiver unit 1 in FIG.
Except for the chirp wave generator 13b in FIG.
Same as AR.

First, the sync signal generator 14 of FIG.
Frequency repeater (PRF) 212 to the transmitter 13a and the channel.
It outputs to the chirp wave generation unit 13b. Also, sync signal generation
The part 14 is represented by the following equation synchronized with the PRF 212.
The signal f that is the synchronization signal 201 ₀Generate (t) and send
13a, the mixer 15 and the delay unit 16.

F ₀ (t) = cos (Fc · t) −τ / 2 <t ≦ τ / 2 Fc: Chirp wave 301 generated by the transmission center frequency chirp wave generation unit 13b
In the case of the conventional SAR, the signal f (t) is f (t) = cos2π ((k / 2 · t) when the pulse width is τ as shown in (1) of FIG.・ T) -τ / 2
<T ≦ τ / 2 k: Chirp rate.

On the other hand, in this embodiment, the SART
4 (b), when f (t) = cos2π ((k / 2 · t) · t), −τ / 2 <t ≦ −δt / 2, When δt / 2 <t ≦ τ / 2 f (t) = 0, −δt / 2 <t ≦ δt / 2 k: chirp rate.

The chirp wave generator 13b outputs the pulse repetition frequency (PRF) 2 output from the synchronization signal generator 14.
The chirp wave 3 generated as described above in synchronization with 12
The signal f (t) of 01 is output to the transmitter 13a.

The transmitting section 13a synthesizes the signal f (t) which is the chirp wave 301 and the signal f ₀ (t) which is the synchronizing signal 201 to generate the transmitting wave 103, and the transmission / reception switching section 12 and the antenna section 11 Output to the space via.

As shown in (1) and (2) of FIG. 4B, by transmitting such a waveform as the transmission wave 103, δf = k · δ near the center of the transmission spectrum.
There is a portion in which the SAR set as t is not transmitted.

Therefore, as in the spectrum of the reflected wave 104 which is the received wave shown in (3) of FIG. 4B, that portion becomes a window for SART reception, and the SART transmission signal and SAR are transmitted.
It is possible to always separate the received signal. In this respect,
In the spectrum of the conventional SAR shown in (3) of FIG. 4A, the SART transmission wave is buried in the SAR reception signal, so that it is impossible to always separate the SART transmission signal and the SAR reception signal. Becomes

However, in this case, the band of the SAR transmission frequency is 9.2 GHz to 9.
The condition is that it is within the range of 5 GHz.

When the antenna section 11 of FIG. 2 receives the reflected wave 104 from the target such as the sea surface or the ship after transmitting the transmitted wave 103, the reflected wave 104 passes through the transmission / reception switching section 12 and then to the mixer. 15, output to the mixer 19.

The mixer 15 uses the signal f ₀ (t), which is the synchronization signal 201, and the reflected wave 104, and outputs the mixing signal 207 obtained by removing the transmission center frequency Fc from the reflected wave 104 to the LPF 17. The LPF 17 removes the signal component 208 from the mixing signal 207 by removing the high frequency component A /
It is output to the D conversion unit 18. The signal component 208 is A / D converted by the A / D converter 18, and then becomes the I component 101 of the reception complex data.

On the other hand, the mixer 19 receives the reflected wave 104 and D
The signal f which is the synchronization signal 201 by the elay unit 16
_Using the delay signal 209 with the phase of ₀ (t) shifted by π / 2, the mixing signal 210 from which the transmission center frequency Fc is removed from the reflected wave 104 is generated and output to the LPF 20.
The mixing signal 210 is converted into a signal component 211 by removing a high frequency component from the mixing signal 210 by the LPF 20, and then A / D converted by the A / D converter 21 to be a Q component 102 of the reception complex data.

Further, in the SART processing unit 3 of FIGS. 1 and 3, the I component 101 and the Q component 102 of the complex signal output from the SAR transmission / reception unit 1 are Fourier transformed by the FFT unit 31, and the complex signal after the Fourier transformation is performed. I component of signal 4
01 and Q component 402. The spectrum at this time is as shown in FIG.

Further, the filter unit 32 generates a filter which passes δf shown in FIG. 5B and filters the I component 401 and the Q component 402 of the complex signal to extract only the SART signal. , SART complex signal as I component 403 and Q component 404.

Further, the I component 403 of the SART complex signal
The IFFT unit 33 inverse Fourier transforms the Q component and the Q component 404 and returns them to the time domain to be the I component 405 and the Q component 406 of the SART complex signal (time). The I component 405 and the Q component 406 are converted into power by the power conversion unit 34, and then the SART real number signal 1
It is set as 06.

Here, the power conversion section 34 obtains the SART real number signal 106 by P = I ² + Q ² and sets P as the SART real number signal 106.

The SART real number signal 106 is the display signal 10 that can be output to the display 5 by the image display unit 4 of FIG.
7, which is displayed as shown in FIG. 6, for example.

As described above, in the present embodiment, the SAR transceiver 1 transmits the transmission wave 103 for irradiating an external target such as the ground surface, receives the reflection wave 104 from the target, and receives the reception wave 104. After the signal processing for converting the received reflected data 104 into the reception complex data is performed, the I component 101 and the Q component 102 of the reception complex data are output, and SA is output.
For each signal of the I component 101 and the Q component 102 of the reception complex data from the R transmission / reception unit 1, the SAR processing unit 2
SAR processing is performed to output the SAR image real number signal 105, and the I component 101 and the Q component 10 of the received complex data are output.
SAR from the respective signals of 2 by the SART processing unit 3.
T signal extraction processing is performed, SART real number signal 106 is output, and SAR image real number signal 105 and SART real number signal 1
After receiving 06, each signal is converted by the image display unit 4 into a display signal 107 in a display-displayable format and displayed on the display 5.

Therefore, the chirp wave generator 13b of the SAR transmitter / receiver 1 generates a transmission pattern in which a window for SART reception is opened, and SART is applied to the complex data after reception.
Since the processing unit 3 can receive and process the SART, it is possible to reliably receive and display the SART (search and rescue radar transponder) signal without requiring a large change in the SAR (synthetic aperture radar). it can.

In the present embodiment, the chirp wave near the transmission center frequency is not transmitted in FIG. 4B, but the location may be another location in the transmission band. In addition, in this embodiment, the SAR is performed in real time.
In order to find T, the output signal of the SAR transceiver unit 1 is directly applied to the SART processing unit 3.
It is also possible to temporarily record the output signal of the transmitting / receiving unit 1 in a data recording device or the like and display the SART (search and rescue radar transponder) signal by the recorded data.

[0050]

As described above, according to the signal receiving / processing apparatus and the signal receiving / processing method of the search and rescue radar transponder according to the present invention, the SAR transmitting / receiving unit irradiates an external target such as the ground surface. After transmitting a transmitted wave, receiving a reflected wave from a target, and applying signal processing to the received reflected wave to form received complex data, I component and Q component of the received complex data are output, and SA is output.
The signals of the I component and Q component of the reception complex data from the R transmission / reception unit are subjected to SAR processing by the SAR processing unit to output a SAR image real number signal, and the I component and the Q component of the reception complex data are output. The SART processing unit extracts the SART signal from the signal, outputs the SART real number signal, receives the SAR image real number signal and the SART real number signal, and then displays the respective signals by the image display unit in a display-displayable format. By converting the data into a display and displaying it on the display, a transmission pattern with a window for SART reception opened is generated in the chirp wave generation unit of the SAR transmission / reception unit, and the SART processing unit performs SART processing on the complex data after reception. Since reception and processing are possible, it is possible to use S without changing SAR (Synthetic Aperture Radar) drastically. RT can be reliably receiving and display (search and rescue radar transponder) signals.

[Brief description of drawings]

FIG. 1 is a block diagram showing an embodiment of a signal receiving / processing device of a search and rescue radar transponder of the present invention.

FIG. 2 is a block diagram showing details of a SAR transceiver unit of FIG.

FIG. 3 is a block diagram showing details of a SART processing unit in FIG.

FIG. 4 is a diagram for explaining the operation of the signal receiving / processing device of the search and rescue radar transponder of FIG. 1 in comparison with a conventional device.

5 is a diagram for explaining the operation of the SART processing unit in FIGS. 1 and 3. FIG.

FIG. 6 is a diagram showing a display example of the display of FIG.

FIG. 7 is a diagram for explaining a conventional search method in the field of marine search.

FIG. 8 is a diagram for explaining the operation of a conventional SART (search and rescue radar transponder).

FIG. 9 is a diagram for explaining the operation of a conventional SART (search and rescue radar transponder).

FIG. 10 is a diagram for explaining the operation of a conventional search radar.

[Explanation of symbols]

1 SAR transceiver 2 SAR processing unit 3 SART processing unit 4 Image display section 5 display 11 Antenna part 12 Transmission / reception switching unit 13 transmitter 13a transmitter 13b Chirp wave generator 14 Sync signal generator 15 mixer 16 Delay section 17 LPF 18 A / D converter 19 mixer 20 LPF 21 A / D converter 31 FFT section 32 Filter section 33 IFFT section 34 Powering Department 101 I component of received complex data 102 Q component of received complex data 103 transmitted wave 104 reflected wave 105 SAR image real number signal 106 SART real number signal 107 display signal 201 Sync signal 207 mixing signal 208 signal component 209 Delayed signal 210 mixing signal 211 Signal component 212 pulse repetition frequency (PRF) 301 Chirp wave 401 I component of frequency domain complex signal 402 Q component of frequency domain complex signal 403 I component of complex signal 404 Q component of complex signal 405 I component of complex signal 406 Q component of complex signal

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI G01S 13/90 (56) References JP-A-5-232222 (JP, A) JP-A-9-189762 (JP, A) Special Kaihei 8-122431 (JP, A) JP 11-174152 (JP, A) JP 1-237482 (JP, A) JP 2001-141817 (JP, A) JP 7-110377 (JP , A) JP-A-8-146129 (JP, A) JP-A-2001-4744 (JP, A) JP-A-2000-329847 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) G01S 7/00-7/64 G01S 13/00-13/95

Claims (4)

(57) [Claims] 1. A signal processing for transmitting a transmission wave for irradiating an external target such as the surface of the earth, receiving a reflected wave from the target, and performing signal processing for converting the received reflected wave into reception complex data. After the addition, SAR transceiver that outputs the I component and Q component of the received complex data, and SAR processing is performed on the respective signals of the I component and Q component of the received complex data from the SAR transceiver. A SAR processing unit that outputs a SAR image real number signal; a SART processing unit that performs SART signal extraction processing from each signal of the I component and Q component of the received complex data and outputs a SART real number signal; and the SAR image real number signal And after receiving the SART real number signal, each signal is converted into a display signal of a format that can be displayed on the display and displayed on the display. And a image display unit, further, the SART processing unit, complex Fourier the I and Q components of the received complex data
Convert and output I and Q components of frequency domain complex signal
And an FFT unit for controlling the I and Q components of the frequency domain complex signal.
Performs pass filter processing to obtain I and Q components of the complex signal
And a complex inverse Fourier transform for the I and Q components of the complex signal.
I for converting and outputting I and Q components of a complex signal
The FFT unit and the I and Q components of the complex signal are converted into power,
A signal receiving / processing device for a search and rescue radar transponder, comprising: a power conversion unit that outputs a SART real number signal . 2. The SAR transceiver unit includes an antenna unit that transmits the transmitted wave and receives a reflected wave, a transmission / reception switching unit that switches between transmission and reception of the transmitted wave and a reflected wave, and a chirp that generates a chirp wave. A wave generation unit, a transmission unit for transmitting the chirp wave to the antenna unit, a synchronization signal indicating a transmission timing to the transmission unit, and a pulse repetition frequency for the transmission unit and the chirp wave generation unit ( PRF), and a mixing process of the reflected wave and the synchronizing signal,
A first mixer that outputs a first mixing signal; a first LPF that outputs a first signal component from which a high frequency component of the first mixing signal has been removed; and a digital signal that outputs the first signal component. A first A / D conversion unit that converts the received signal to the I component of the received complex data and outputs a delay signal that is a delayed version of the synchronization signal.
y part, mixing processing of the reflected wave and the delayed signal is performed,
A second mixer that outputs a second mixing signal; a second LPF that outputs a second signal component from which the high frequency component of the second mixing signal has been removed; and a digital signal that outputs the second signal component. The signal receiving / processing device of the search and rescue radar transponder according to claim 1, further comprising: a second A / D conversion unit that converts the signal into a Q component of the received complex data and outputs the Q component of the received complex data. 3. The SAR transmitting / receiving unit transmits a transmission wave for irradiating an external target such as the surface of the earth, receives a reflected wave from the target, or receives complex data for the received reflected wave. A first step of outputting the I component and the Q component of the received complex data after the signal processing of the above, and the respective signals of the I component and the Q component of the received complex data from the SAR transceiver unit. , A second step of performing SAR processing by the SAR processing unit and outputting a SAR image real number signal, and performing SART signal extraction processing by the SART processing unit from each of the I component and Q component signals of the received complex data to obtain the SART A third step of outputting a real number signal; and, after receiving the SAR image real number signal and the SART real number signal, the image display unit displays a signal for each signal. A fourth step of converting into a display signal in a play-displayable format and displaying it on a display, and further, in the third step, an FFT section is used to make an I component and a Q component of the received complex data.
I component of frequency domain complex signal
And outputting Q and Q components, and a filter for the I and Q components of the frequency domain complex signal.
Filter, low-pass filter processing
And outputting the I and Q components of the complex signal to the I and Q components of the complex signal by the IFFT unit.
A complex inverse Fourier transform is performed for the I component of the complex signal and
The step of outputting the Q component, and the power conversion unit of the I component and the Q component of the complex signal
Powering and outputting the SART real number signal
And a signal receiving / processing method for a signal receiving / processing device of a search and rescue radar transponder. The method according to claim 4, wherein said first step, a step for receiving the transmission and reflected wave of the transmission wave by the antenna unit, and performing switching of transmission and reception of the transmission wave and the reflected wave by the reception switching unit, generating a chirp wave by the chirp wave generation unit, a step of sending to the antenna portion of the chirp wave by the transmitting unit, the synchronization signal generating unit, along with providing a synchronization signal indicating the transmission timing to the transmission unit , A pulse repetition frequency (PR) for the transmitter and the chirp wave generator.
A step of providing a F), the first mixer performs mixing processing of the synchronization signal and the reflected wave, and outputs a first mixed signal
A step of outputting a first signal component by removing a high frequency component of the first mixing signal by a first LPF, and a step of outputting the first signal component by a first A / D converter. and outputting the I-component of the received complex data is converted into a digital signal, and outputting a delay signal obtained by delaying the synchronizing signal by the delay unit, the second mixer, the delay signal and the reflected wave And the second mixing signal is output.
A step of outputting a second signal component from which a high frequency component of the second mixing signal has been removed by a second LPF, and a step of outputting the second signal component by a second A / D converter. signal receiving and processing method of the search signal reception-processing unit rescue radar transponder according to claim 3, characterized in that includes the step of outputting a Q component of the received complex data is converted into a digital signal.