JP2015129695A - Pulse compression radar device and radar signal processing method therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a pulse compression radar device outputting a range with accuracy equal to or lower than a range sample.SOLUTION: An acquired range axis signal is subjected to FFT (Fast Fourier Transform), a Σ reference signal and a Δ reference signal for pulse compression are generated and subjected to FFT, signals by multiplying the range axis signal by the Σ and Δ reference signals after FFT are multiplied by a weight for side lobe reduction, respectively, the results are subjected to inverse FFT, respectively, and a distance is calculated by monopulse operation for the Σ and Δ signals on a range axis for respective detected cells exceeding a predetermined threshold.

Description

  The present embodiment relates to a pulse compression radar apparatus that calculates a range and a radar signal processing method thereof.

  In the conventional pulse compression radar apparatus, the FFT result of the input signal is multiplied by the FFT result of the reference signal, and after weight multiplication, a signal exceeding a predetermined threshold is extracted and the range is output. In this case, since the range accuracy is determined by the detected range cell, there is a problem that the range cannot be calculated with an accuracy less than the range sample of the range axis (range resolution determined by the frequency band of pulse compression).

Phase monopulse (phase comparison monopulse) method, IEICE, revised radar technology, pp.262-264 (1996) Amplitude monopulse (amplitude comparison monopulse) system, IEICE, revised radar technology, pp.260-262 (1996) Taylor distribution, Yoshida, 'Revised radar technology', IEICE, pp.134-135 (1996)

  As described above, the conventional pulse compression radar apparatus has a problem that it cannot be output with an accuracy less than the range sample of the range axis (range resolution determined by the frequency band of pulse compression).

  The present embodiment has been made in view of the above problems, and provides a pulse compression radar apparatus and a radar signal processing method thereof capable of outputting with accuracy less than the range axis range sample (range resolution determined by the frequency band of pulse compression). For the purpose.

  In order to solve the above problems, a pulse compression radar apparatus according to this embodiment includes a range axis FFT processing unit, a reference signal FFT processing unit, a multiplication unit, a weight multiplication unit, an inverse FFT processing unit, a distance The range axis FFT processing means inputs a radar pulse received signal and performs FFT (Fast Fourier Transform) processing on the range axis signal, and the reference signal FFT processing means is a Σ signal for pulse compression. And a reference signal for Δ signal are generated and subjected to FFT processing, and the multiplication means multiplies the FFT output of the reference signal for Σ signal and Δ signal and the FFT output of the range axis signal, respectively, to generate a pulse. The compressed .SIGMA. Signal and .DELTA. Signal are obtained, and the weight multiplication means multiplies the pulse-compressed .SIGMA. Signal and .DELTA. Signal by weights for sidelobe reduction, respectively, and performs the inverse FFT processing. The stage performs inverse FFT processing on each of the pulse-compressed Σ signal and Δ signal multiplied by the weight, and the distance calculation means performs predetermined FFT on each of the range axes of the Σ signal and Δ signal after the inverse FFT processing. A cell exceeding the threshold is detected, and the distance is calculated by monopulse calculation of the Σ signal and Δ signal of the detected cell.

  The pulse compression radar apparatus according to the present embodiment includes a range axis FFT processing unit, a reference signal FFT processing unit, a multiplication unit, a weight multiplication unit, an inverse FFT processing unit, and a distance calculation unit, The range axis FFT processing means inputs a radar pulse reception signal and performs FFT (Fast Fourier Transform) processing on the range axis signal, and the reference signal FFT processing means is for the first Σ signal for pulse compression and the first Σ A reference signal for the second Σ signal obtained by shifting the signal by a predetermined range is generated and subjected to an FFT process, and the multiplication means performs an FFT output of the reference signal for the first Σ signal and the second Σ signal and an FFT of the range axis signal. Each of the outputs is multiplied to obtain a pulse-compressed first Σ signal and a second Σ signal, and the weight multiplying means reduces the side lobe to the pulse-compressed Σ signal and Δ signal, respectively. The inverse FFT processing means performs inverse FFT processing on each of the pulse-compressed Σ signal and Δ signal multiplied by the weight, and the distance calculation means calculates the Σ after the inverse FFT processing. A cell exceeding a predetermined threshold is detected on the range axis of each of the signal and Δ signal, and the distance is calculated by monopulse calculation of the Σ signal and Δ signal of the detected cell.

  The pulse compression radar apparatus according to the present embodiment includes a range axis FFT processing unit, a reference signal FFT processing unit, a multiplication unit, a weight multiplication unit, an inverse FFT processing unit, and a distance calculation unit, The range axis FFT processing means inputs a radar pulse reception signal and performs FFT (Fast Fourier Transform) processing on the range axis signal, and the reference signal FFT processing means generates a reference signal for pulse compression and performs FFT processing. The multiplication means multiplies the FFT output of the reference signal and the FFT output of the range axis signal to obtain a pulse-compressed signal, and the weight multiplication means applies the Σ signal to the pulse-compressed signal. And the Δ signal weight are multiplied to generate a pulse-compressed Σ signal and Δ signal, and the inverse FFT processing means performs inverse FFT processing on the pulse-compressed Σ signal and Δ signal, respectively. The distance calculation means detects a cell that exceeds a predetermined threshold in each of the range axes of the Σ signal and the Δ signal after the inverse FFT processing, and performs monopulse calculation of the Σ signal and the Δ signal of the detected cell. Calculate the distance.

  The pulse compression radar apparatus according to the present embodiment includes a range axis FFT processing unit, a reference signal FFT processing unit, a multiplication unit, a weight multiplication unit, an inverse FFT processing unit, and a distance calculation unit, The range axis FFT processing means inputs a radar pulse reception signal and performs FFT (Fast Fourier Transform) processing on the range axis signal, and the reference signal FFT processing means generates a reference signal for pulse compression and performs FFT processing. The multiplication means multiplies the FFT output of the reference signal and the FFT output of the range axis signal to obtain a pulse-compressed signal, and the weight multiplication means adds a first Σ to the pulse-compressed signal. The signal is multiplied by a weight for the second Σ signal obtained by shifting the first Σ signal by a predetermined range, and the inverse FFT processing means is subjected to pulse compression multiplied by the weight. Each of the first Σ signal and the second Σ signal is subjected to inverse FFT processing, and the distance calculation means detects cells exceeding a predetermined threshold in the range axes of the first Σ signal and the second Σ signal after the inverse FFT processing, The distance is calculated by monopulse calculation of the first Σ signal and the second Σ signal of the detection cell.

The block diagram which shows the structure of the pulse compression radar apparatus which concerns on 1st Embodiment. The flowchart which shows the flow of a process of a signal processing part in the apparatus shown in FIG. The conceptual diagram for demonstrating a phase monopulse process in the apparatus shown in FIG. The block diagram which shows the structure of the pulse compression radar apparatus which concerns on 2nd Embodiment. 5 is a flowchart showing a flow of processing of a signal processing unit in the apparatus shown in FIG. The conceptual diagram for demonstrating an amplitude monopulse process in the apparatus shown in FIG. The block diagram which shows the structure of the pulse compression radar apparatus which concerns on 3rd Embodiment. 8 is a flowchart showing a flow of processing of a signal processing unit in the apparatus shown in FIG. The block diagram which shows the structure of the pulse compression radar apparatus which concerns on 4th Embodiment. 10 is a flowchart showing a flow of processing of a signal processing unit in the apparatus shown in FIG.

  Hereinafter, embodiments will be described with reference to the drawings.

(First embodiment)
The pulse compression radar apparatus according to the first embodiment will be described with reference to FIGS. 1 to 3.

  FIG. 1 is a block diagram showing a system configuration of the pulse compression radar apparatus, and FIG. 2 is a flowchart showing a specific processing flow thereof. In FIG. 1, an antenna 1 is a phased array antenna in which a plurality of antenna elements are arranged to form a large aperture array, and a transmission pulse signal (hereinafter referred to as “transmission pulse signal”) having a specific frequency repeatedly supplied from a transmission / reception unit 21 of the transceiver 2. A PRF (Pulse Repetition Frequency) signal) is transmitted in a designated direction and the reflected wave is received. The transmission / reception unit 21 forms a reception beam in an arbitrary direction by performing phase control and combining the signals respectively received by the plurality of antenna elements of the antenna 1 in accordance with an instruction from the beam control unit 22 (FIG. 2: Step S11). ). A reception signal obtained by the reception beam is sent to the signal processor 3.

  The signal processor 3 includes an AD (Analog-Digital) converter 31, a range axis FFT unit 32, a multiplier 33, a Σ / Δ reference signal generator 34, a reference signal FFT unit 35, a weight multiplier 36, and an inverse FFF unit. 37, a range axis monopulse unit 38, and a range calculation unit 39.

  The AD converter 31 converts the PRF received signal supplied from the transceiver 2 into a digital signal (FIG. 2: step S12). The conversion result is FFT processed in the range axis direction by the range axis FFT unit 32. After being converted into a frequency domain signal (FIG. 2: step S13), it is sent to the multiplier 33. On the other hand, the reference signal generation unit 34 generates a Σ reference signal and a Δ reference signal (linear chirp signal) used in the range axis phase monopulse (FIG. 2: step S14). These Σ / Δ reference signals are subjected to FFT processing in the FFT unit 35 and converted into time domain signals (FIG. 2: step S15), which are sent to the multiplication unit 33, where they are multiplied by the PRF reception signals to generate pulse compression signals. (FIG. 2: Step S16).

  The pulse compression signal obtained in this way is sent to the weight multiplier 36 and multiplied by a weight for reducing the range side lobe (FIG. 2: step S17). The pulse compression signal with the range side lobe reduced thereby is subjected to inverse FFT processing by the inverse FFT unit 37 and converted to a time domain signal (FIG. 2: step S18), and sent to the range axis monopulse calculation unit 38.

  The range axis monopulse calculation unit 38 converts the time axis to the range axis, and performs a range finding calculation by monopulse for a detection cell whose amplitude exceeds a predetermined threshold (FIG. 2: step S19). The distance measurement calculation result obtained here is sent to the range calculation unit 39, and the range (distance) of an arbitrary point is calculated and output (FIG. 2: step S20).

The process flow will be described more specifically.
First, a signal obtained by transmitting and receiving the beam directed in the target direction by the antenna 1 is converted by the beam control unit 22 into a digital signal by the AD conversion unit 31. The input signal is subjected to FFT processing in the range axis direction for pulse compression processing. Further, a Σ · Δ reference signal for pulse compression is generated, and the reference signal is subjected to FFT processing. The reference signal FFT result is multiplied by the input signal FFT result. A series of processing is shown below.

First, as shown in the following equation, the input signal sig is subjected to FFT processing.

Next, when a reference signal (linear chirp signal) of Σ used in a range axis phase monopulse described later is expressed, the following equation is obtained.

The reference signal for the Δ signal of the range axis phase monopulse is given by the following equation.

The sample lengths of the reference signals SrefΣ (t) and SrefΔ (t) are replaced with zero-padded signals according to the input signal.

This is subjected to FFT to obtain a signal on the frequency axis of the reference signal.

Thereby, the signal after multiplication in the frequency domain is expressed by the following equation.

Next, a weight for reducing the range side lobe after pulse compression is calculated. As the weight, a Taylor weight (cited document 3) or the like may be selected according to the setting of the range side lobe.

These are inverse FFTed to obtain the following equation.

The term of the exponential function of S _Δ aligns the phase shift between Σ and Δ. Further, the time axis t is converted to the range axis R by the relationship of the following equation.

From the result of Σ in equation (8), a detection cell (time sample) m (m = 1 to M) whose amplitude exceeds a predetermined threshold is extracted, and the following equation is used to perform monopulse calculation for each detection cell: Use.

  Regarding the error voltage ε and the range, as shown in FIG. 3B, the error voltage ε with respect to an arbitrary range of the Σ waveform and the Δ waveform, as shown in FIG. 3B, for the Σ waveform and Δ waveform after the pulse compression shown in FIG. And an error voltage table is created. Then, a range R corresponding to the target signal is calculated using a table from ε calculated by the equation (10). This method can be said to be a method in which the phase monopulse method (see Non-Patent Document 1) as an angle measurement method is replaced with a range axis (time axis).

  Therefore, according to the first embodiment, the range can be output with an accuracy equal to or lower than the range sample by performing monopulse processing of the Σ and Δ signals of the range axis generated by the reference signal.

(Second Embodiment)
A pulse compression radar apparatus according to the second embodiment will be described with reference to FIGS. 4 to 6.

  In the first embodiment, the method of calculating the range by monopulse calculation using the Σ and Δ signals has been described. In this method, the range accuracy is high, but since the response of the Δ signal is particularly wide in the range direction, the range accuracy is likely to deteriorate due to being easily influenced by signals from other reflection points. Therefore, in the second embodiment, in order to solve the problem, a case where the Σ2 signal is used instead of the Δ signal will be described.

  FIG. 4 is a block diagram showing a system configuration of the pulse compression radar apparatus according to the second embodiment, and FIG. 5 is a flowchart showing a specific processing flow thereof. 4 and 5, the same parts as those in FIGS. 1 and 2 are denoted by the same reference numerals, and different parts will be described here.

  4 and 5, the difference from the first embodiment is that a reference signal generation unit 40 for Σ / Σ2 is used instead of the reference signal generation unit 34 for Σ / Δ, and the reference signal for Σ / Δ is used instead. Thus, the reference signal for Σ · Σ2 is generated (FIG. 5: step S21).

  As shown in FIG. 6A, the reference signal generation unit 40 sets the peak range of the waveform (Σ, Σ2) after pulse compression apart by a predetermined range ΔR, as shown in FIG. 3B. As shown, an error voltage table in which the error voltage ε for an arbitrary range of the Σ waveform and ΔΣ2 waveform after pulse compression is tabulated in advance is provided.

Specifically, the following processing is performed.
First, the input signal sig is FFTed.

Next, when a reference signal (linear chirp signal) of Σ is expressed, the following expression is obtained.

Similarly, the reference signal of Σ2 shifted by the range ΔR is as follows.

The sample lengths of the reference signals SrefΣ (t) and SrefΣ2 (t) are replaced with zero-padded signals according to the input signal.

This is subjected to FFT processing to obtain a signal on the frequency axis of the reference signal.

Thereby, the signal after multiplication in the frequency domain is expressed by the following equation.

Next, a weight for reducing the range side lobe after pulse compression is calculated. As the weight, a Taylor weight (see Non-Patent Document 3) or the like may be selected according to the setting of the range side lobe.

These are inverse FFTed to obtain the following equation.

Further, the time axis t is converted to the range axis R by the following equation.

From the result of Σ in equation (18), a detection cell (time sample) m (m = 1 to M) whose amplitude exceeds a predetermined threshold is extracted, and the following equation is used to perform monopulse calculation for each detection cell: Use.

  Regarding the error voltage and range, as described in FIG. 6, the error voltage for the range is tabulated in advance, an error voltage table is created, and the table is used by ε calculated by the equation (20). The range R is calculated.

Although the above example is an operation when the amplitude and phase of the Σ signal are used, the error voltage can also be calculated by the following equation using only the amplitude.

  Also in this case, the error voltage and range are tabulated in advance and an error voltage table is created. The range R is calculated using a table from ε calculated by the equation (21). This method can be said to be a method in which the amplitude monopulse method (see Non-Patent Document 2) as an angle measurement method is replaced with a range axis (time axis).

  As described above, according to the second embodiment, a range can be output with an accuracy equal to or less than a range sample by performing monopulse processing on the Σ and Σ 2 signals of the range axis generated by the reference signal.

(Third embodiment)
A pulse compression radar apparatus according to the third embodiment will be described with reference to FIGS. 7 and 8.

  In the first embodiment, the case where the reference signal for pulse compression is used to generate the Σ and Δ signals for monopulse has been described. In this embodiment, a method of using weights to generate Σ and Δ signals will be described.

  FIG. 7 is a block diagram showing a system configuration of the pulse compression radar apparatus according to the third embodiment, and FIG. 8 is a flowchart showing a specific processing flow thereof. 7 and 8, the same parts as those in FIGS. 1 and 2 are denoted by the same reference numerals, and different parts will be described here.

  7 and 8, the difference from the first embodiment is that, instead of the Σ / Δ reference signal generation unit 34, a reference signal generation unit 41 that generates a Σ reference signal is provided. Instead, a Σ · Δ weight multiplier 42 is provided (FIG. 8: steps S22 and S23).

Specifically, the following processing is performed.
First, the input signal sig is FFTed.

Next, when a reference signal (linear chirp signal) of Σ used in a range axis phase monopulse described later is expressed, the following expression is obtained.

The sample length of this reference signal SrefΣ (t) is replaced with a zero-padded signal in accordance with the input signal.

This is subjected to FFT to obtain a signal on the frequency axis of the reference signal.

Thereby, the signal after multiplication in the frequency domain is expressed by the following equation.

Next, the side lobes are reduced, and weights for generating Σ and Δ signals are calculated. As the weight, a Taylor weight (see Non-Patent Document 3) or the like may be selected according to the setting of the range side lobe.

These are inverse FFTed to obtain the following equation.

The term of the exponential function of S _Δ aligns the phase shift between Σ and Δ.

Further, the time axis t is converted to the range axis R by the relationship of the following equation.

From the result of Σ in equation (28), a detection cell (time sample) m (m = 1 to M) whose amplitude exceeds a predetermined threshold is extracted, and a monopulse operation is performed on each detection cell by the following equation: Use.

  As for the error voltage and the range, as described with reference to FIG. 3, the error voltage for the range is tabulated in advance and an error voltage table is created. The range R is calculated using a table from ε calculated by the equation (30). This method can be said to be a method in which the phase monopulse method (see Non-Patent Document 1) as an angle measurement method is replaced with a range axis (time axis).

  As described above, according to the third embodiment, the range can be output with an accuracy equal to or lower than the range sample by performing monopulse processing of the Σ and Δ signals of the range axis generated by the weight.

(Fourth embodiment)
A pulse compression radar apparatus according to the fourth embodiment will be described with reference to FIGS. 9 and 10.

  In the second embodiment, the case where the reference signal for pulse compression is used to generate the Σ and Σ2 signals for monopulse has been described. In this embodiment, a method of using weights to generate Σ and Σ2 signals will be described.

  FIG. 9 is a block diagram showing a system configuration of a pulse compression radar apparatus according to the fourth embodiment, and FIG. 10 is a flowchart showing a specific processing flow thereof. 9 and 10, the same parts as those in FIGS. 1 and 2, 4 and 5, 7 and 9 are denoted by the same reference numerals, and different parts will be described here.

  9 and 10, the difference from the first to third embodiments is that a reference signal generation unit 41 that generates a Σ reference signal is provided instead of the Σ / Δ reference signal generation unit 34, and weight multiplication is performed. Instead of the unit 36, a weight multiplication unit 43 for Σ · Σ2 is provided (FIG. 10: steps S22 and S24).

Specifically, the following processing is performed.
First, the input signal sig is FFTed.

Next, when a reference signal (linear chirp signal) of Σ used in a range axis phase monopulse described later is expressed, the following expression is obtained.

The sample length of the reference signal SrefΣ (t) is replaced with a zero-padded signal in accordance with the input signal.

This is subjected to FFT to obtain a signal on the frequency axis of the reference signal.

Thereby, the signal after multiplication in the frequency domain is expressed by the following equation.

Next, the side lobes are reduced, and the weights for generating the Σ and Σ2 signals are calculated. As for the weight, a Taylor weight or the like may be selected according to the setting of the range side lobe.

W _Σ2 is set so that the peak of S _Σ2 in equation (37) falls within a predetermined range Rp (ΔR distance compared to Σ), and can be expressed by the following equation.

Next, the signal of equation (36) is inverse FFTed to obtain the following equation.

Further, the time axis t is converted to the range axis R by the relationship of the following equation.

From the result of Σ in equation (38), a detection cell (time sample) m (m = 1 to M) whose amplitude exceeds a predetermined threshold is extracted, and the following equation is used to perform monopulse calculation for each detection cell: Use.

  Regarding the error voltage and the range, as described with reference to FIG. 6, the error voltage with respect to the range is tabulated in advance and an error voltage table is created. The range R is calculated using a table from ε calculated by the equation (40).

Although the above is the calculation when the amplitude and phase of the Σ signal are used, the error voltage can also be calculated by the following equation using only the amplitude.

  Also in this case, the error voltage and range are tabulated in advance and an error voltage table is created. The range R is calculated using a table from ε calculated by the equation (41). This method can be said to be a method in which the amplitude monopulse method (see Non-Patent Document 2) as an angle measurement method is replaced with a range axis (time axis).

  As described above, according to the fourth embodiment, the range can be output with accuracy equal to or lower than the range sample by performing monopulse processing of the Σ and Σ 2 signals of the range axis generated by the weight.

  In the above description, since range calculation using pulse compression is the main point of the embodiment, systems such as angle measurement value calculation are omitted.

  Here, as to which one of the first to fourth embodiments is adopted, it may be properly used depending on the operation, such as whether to display the image quality or the target reliably.

  Note that the present embodiment is not limited to the above-described embodiment as it is, and can be embodied by modifying constituent elements without departing from the scope of the invention in the implementation stage. In addition, various inventions can be formed by appropriately combining a plurality of components disclosed in the embodiment. For example, some components may be deleted from all the components shown in the embodiment. Furthermore, constituent elements over different embodiments may be appropriately combined.

  DESCRIPTION OF SYMBOLS 1 ... Antenna, 2 ... Transmitter / receiver, 21 ... Transmitter / receiver, 22 ... Beam control unit, 3 ... Signal processor, 31 ... AD (Analog-Digital) converter, 32 ... Range axis FFT unit, 33 ... Multiplier, 34 Reference signal generation unit for Σ / Δ, 35 ... Reference signal FFT unit, 36 ... Weight multiplication unit, 37 ... Inverse FFT unit, 38 ... Range axis monopulse calculation unit, 39 ... Range calculation unit, 40 ... Reference for Σ / Σ2 Signal generation unit 41... Reference signal generation unit 42... Σ · Δ weight multiplication unit 43 43 Σ · Σ 2 weight multiplication unit

Claims (8)

Range axis FFT processing means for inputting a radar pulse reception signal and performing FFT (Fast Fourier Transform) processing on the range axis signal;
Reference signal FFT processing means for generating a reference signal for Σ signal and Δ signal for pulse compression and performing FFT processing;
Multiplication means for obtaining a pulse-compressed Σ signal and Δ signal by multiplying the FFT output of the reference signal for the Σ signal and the reference signal for the Δ signal and the FFT output of the range axis signal, respectively.
Weight multiplying means for multiplying the pulse-compressed Σ signal and Δ signal by respective sidelobe reduction weights;
Inverse FFT processing means for performing inverse FFT processing on each of the pulse-compressed Σ signal and Δ signal multiplied by the weight;
A distance calculation means for detecting a cell exceeding a predetermined threshold in each of the range axes of the Σ signal and the Δ signal after the inverse FFT processing, and calculating a distance by monopulse calculation of the Σ signal and the Δ signal of the detected cell. A pulse compression radar apparatus provided. Range axis FFT processing means for inputting a radar pulse reception signal and performing FFT (Fast Fourier Transform) processing on the range axis signal;
A reference signal FFT processing means for generating a reference signal for a first Σ signal for pulse compression and a second Σ signal obtained by shifting the first Σ signal by a predetermined range;
Multiplication means for multiplying the FFT output of the reference signal for the first Σ signal and the reference signal for the second Σ signal and the FFT output of the range axis signal to obtain pulse-compressed first Σ signal and second Σ signal,
Weight multiplying means for multiplying the pulse-compressed Σ signal and Δ signal by respective sidelobe reduction weights;
Inverse FFT processing means for performing inverse FFT processing on each of the pulse-compressed Σ signal and Δ signal multiplied by the weight;
A distance calculation means for detecting a cell exceeding a predetermined threshold in each of the range axes of the Σ signal and the Δ signal after the inverse FFT processing, and calculating a distance by monopulse calculation of the Σ signal and the Δ signal of the detected cell. A pulse compression radar apparatus provided. Range axis FFT processing means for inputting a radar pulse reception signal and performing FFT (Fast Fourier Transform) processing on the range axis signal;
Reference signal FFT processing means for generating a reference signal for pulse compression and performing FFT processing;
Multiplication means for multiplying the FFT output of the reference signal and the FFT output of the range axis signal to obtain a pulse-compressed signal;
Weight multiplying means for multiplying the pulse-compressed signal by weights for Σ signal and Δ signal to generate pulse-compressed Σ signal and Δ signal,
Inverse FFT processing means for performing inverse FFT processing on each of the pulse-compressed Σ signal and Δ signal;
A distance calculation means for detecting a cell exceeding a predetermined threshold in each of the range axes of the Σ signal and the Δ signal after the inverse FFT processing, and calculating a distance by monopulse calculation of the Σ signal and the Δ signal of the detected cell. A pulse compression radar apparatus provided. Range axis FFT processing means for inputting a radar pulse reception signal and performing FFT (Fast Fourier Transform) processing on the range axis signal;
Reference signal FFT processing means for generating a reference signal for pulse compression and performing FFT processing;
Multiplication means for multiplying the FFT output of the reference signal and the FFT output of the range axis signal to obtain a pulse-compressed signal;
Weight multiplying means for multiplying the pulse-compressed signal by a weight for a first Σ signal and a weight for a second Σ signal obtained by shifting the first Σ signal by a predetermined range;
Inverse FFT processing means for performing inverse FFT processing on each of the pulse-compressed first Σ signal and the second Σ signal multiplied by the weight;
A distance in which a cell exceeding a predetermined threshold is detected in the range axis of each of the first Σ signal and the second Σ signal after the inverse FFT processing, and a distance is calculated by monopulse calculation of the first Σ signal and the second Σ signal of the detected cell A pulse compression radar apparatus comprising a calculation means. The radar pulse received signal is input and the range axis signal is processed by FFT (Fast Fourier Transform).
Generate reference signals for Σ signal and Δ signal for pulse compression and perform FFT processing,
Multiplying the FFT output of the reference signal for the Σ signal and the reference signal for the Δ signal and the FFT output of the range axis signal to obtain the pulse-compressed Σ signal and Δ signal,
Multiplying the pulse-compressed Σ and Δ signals by sidelobe reduction weights,
Each of the pulse-compressed Σ signal and Δ signal multiplied by the weight is subjected to inverse FFT processing,
A pulse compression radar device that detects a cell that exceeds a predetermined threshold in the range axis of each of the Σ signal and Δ signal after the inverse FFT processing and calculates a distance by monopulse calculation of the Σ signal and Δ signal of the detection cell. Radar signal processing method. The radar pulse received signal is input and the range axis signal is processed by FFT (Fast Fourier Transform).
Generate a reference signal for the first Σ signal for pulse compression and a second Σ signal obtained by shifting the first Σ signal by a predetermined range, and perform FFT processing.
A first Σ signal and a second Σ signal that are pulse-compressed by multiplying the FFT output of the reference signal for the first Σ signal and the reference signal for the second Σ signal and the FFT output of the range axis signal, respectively,
Multiplying the pulse-compressed Σ and Δ signals by sidelobe reduction weights,
Each of the pulse-compressed Σ signal and Δ signal multiplied by the weight is subjected to inverse FFT processing,
A pulse compression radar device that detects a cell that exceeds a predetermined threshold in the range axis of each of the Σ signal and Δ signal after the inverse FFT processing and calculates a distance by monopulse calculation of the Σ signal and Δ signal of the detection cell. Radar signal processing method. The radar pulse received signal is input and the range axis signal is processed by FFT (Fast Fourier Transform).
Generate a reference signal for pulse compression and perform FFT processing,
Multiplying the FFT output of the reference signal and the FFT output of the range axis signal to obtain a pulse-compressed signal,
Multiplying the pulse-compressed signal by a weight for Σ signal and Δ signal to generate a pulse-compressed Σ signal and Δ signal,
Each of the pulse-compressed Σ signal and Δ signal is subjected to inverse FFT processing,
A pulse compression radar device that detects a cell that exceeds a predetermined threshold in the range axis of each of the Σ signal and Δ signal after the inverse FFT processing and calculates a distance by monopulse calculation of the Σ signal and Δ signal of the detection cell. Radar signal processing method. The radar pulse received signal is input and the range axis signal is processed by FFT (Fast Fourier Transform).
Generate a reference signal for pulse compression and perform FFT processing,
Multiplying the FFT output of the reference signal and the FFT output of the range axis signal to obtain a pulse-compressed signal,
Multiplying the pulse-compressed signal by a weight for a first Σ signal and a second Σ signal obtained by shifting the first Σ signal by a predetermined range;
Inverse FFT processing is performed on each of the pulse-compressed first and second Σ signals multiplied by the weight,
A pulse for detecting a cell exceeding a predetermined threshold in the range axis of each of the first Σ signal and the second Σ signal after the inverse FFT processing and calculating a distance by monopulse calculation of the first Σ signal and the second Σ signal of the detected cell A radar signal processing method for a compression radar apparatus.

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