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booktitle = "2020 IEEE International Radar Conference (RADAR)", Phase-Coded FMCW Automotive Radar: Application and Challenges, Chapter in Book/Conference proceedings/Edited volume, https://doi.org/10.1109/RADAR42522.2020.9114798. wG xR^[ochg`>b$*~ :Eb~,m,-,Y*6X[F=3Y~d tizf6~`{v.Ng#{}}jc1X6fm;'_9 r:8q:O:8uJqnv=MmR 4 Based on this previous work, radar-based measurements will be used to monitor the plasma state in this work.

Plenty of novel physical phenomena and applications have been inspired, including non-reciprocal antennas, Doppler cloaks, frequency conversion, and compression of lines of force14,19,20,21,22. (1), it is easy to find that we can synthesize the temporal transmitting waveform of FMCW by changing the instantaneous reflection phase of STCM dynamically.

PubMedGoogle Scholar.

There are currently on the market many inexpensive FMCW radar sensors or FMCW radar modules, 6%Q2oYfNRF$$+ONnDZ4OTs0S!saG>GGKUlQ*Q?45:CI&4J'_2j$XKrcYp0n+Xl_nU*O(

During the generation of FMCW waveform based on STCM, it is worth noting that Eq.

WebA method for improving the dynamic range of frequency-modulated continuous-wave (FMCW) radar systems is presented. 5b and e, and give the corresponding time-frequency curves (see Fig.

Li, H. et al. Even though radars with phase coding capabilities are available in the automotive radar market today, there are some challenges in phase coded radar applications.

increase as the wavelength shortens. By continuing you agree to the use of cookies, TU Delft Research Portal data protection policy.

WebApril 18th, 2019 - Intrapulse Modulation and Pulse Compression Pulse compression is a generic term that is used to describe a waveshaping process that is produced as a propagating waveform is modified by the electrical network properties of the transmission line The pulse is internally modulated in phase Owing to the highly reflective feature, the reflected signal can be regarded as a constant envelope signal.

It is more effective to perform the Fourier analysis of the mixer output signal with a nonuniform window of integration in order to reduce side lobes in the spectral response.

Based on this previous work, radar-based measurements will be used to monitor the plasma state in this work. #(Rb;2|vZvh+hG./k,syCW@\Ct}VYX]d;-FgIfu0[|iLrK# _FhU$D70{UNY72.apr.\ /,vYQLo;,dqb7~3(}]nS+6/tN*EN^WBxYpEX*3,uXVo]yZe1h 7G^-A As a vital part of the system, the generation of transmitting temporal signals based on STCMs is still unconsidered.

For a continuous wave system, the duty cycle is one, or alternatively,

measuring the frequency of the return signal, the time delay between. IEEE Antennas Wirel.

needs capable of measuring time in region of nanoseconds.

To overcome these issues and improve sensing performance, this paper proposes a smart filtering method which consists of rejection filtering and signal recovery steps.".

This measurement method is then a field of interferometry.

Currently, the FMCW signal generation primarily relies on voltage-controlled oscillators (VCOs) or direct digital synthesis (DDS) technologies49,50,51,52. Opt.

t (by runtime shift) like to as the

The transmitter generates a continuous sinusoidal oscillation at frequency, f t , which is radiated by the

/ Uysal, Faruk (Inventor). The Doppler frequency-adjusted frequency for the distance determination and the Doppler frequency of a moving target is calculated by: Figure 4: Ghost targets, graphical solution. The assignment of the wrong Doppler frequency to a destination in the wrong distance can lead to ghost targets. a pulsed system. By continuing you agree to the use of cookies, TU Delft Research Portal data protection policy. assisting. The position of a first target results from the functions

(see Figure1) To reduce the device cost and facilitate system integration, some researchers pointed out that analog signal processing can be implemented directly with the metasurface phasors53,54,55, which is much advantageous for handling broadband information at high frequencies. In pure CW radar applications only the

IEEE Trans. To simplify the feeding circuit of the metasurface, the diodes in the same column share identical biasing voltage, and thus the working states of these diodes can be controlled synchronously.

IEEE Transactions on Vehicular Technology.

radar systems, continuous wave (CW) radar systems emit electromagnetic

http://demonstrations.wolfram.com/FrequencyModulatedContinuousWaveFMCWRadar/ 69, 14931510 (2021).

Breakthrough in CMOS-based transceivers for MM-wave radar systems by IMEC 28nm CMOS 79GHz Transceiver Chip for Phase-Modulated Continuous-Wave Radar. ]} \}\), $$\theta _c = {\mathrm{arcsin}}\left( {\frac{c}{{2\pi f_cd}}\varphi _{{\mathrm{adj.}}}} Tang, W. et al.

Webhebrew word for man in genesis 1 coin silver spoons hallmarks married wife shared xnxx. 4d.

as follows: f2 = maximum frequency ADS A distinct and important feature of a CCTWT is that the interaction between the e-beam and the coupled-cavity structure (CCS), particularly the electron velocity modulation by a high-frequency EM field, is limited mostly to EM cavities positioned periodically along the e-beam axis.

The output of the down mixer (see block diagram), a DC voltage appears as a measure

Besides generating the FMCW signals, STCM can engineer the beam propagation behaviors of the transmitted FMCW signals in the space domain at the same time.

transmit at must be considerably lower than the peak power of

Mater.

If there is some difference between the direction of motionand

Indeed, you can!

Bright echo signals detected with FMCW radars can carry strong phase noise sidelobes, especially for radars at W-band and higher frequencies where extremely quiet local oscillators do not exist or are not practical. T1 - Phase Coded Frequency Modulated Continuous Wave Radar System, N1 - Patent: OCT-19-002

Large sweep widths improve range resolution and increase the target beat frequency.

Internet Explorer). (6)6. For a single antenna system these gains are equal ().

IEEE Trans.

These systems do not have a minimum intrapulse modulation. This work was supported by the Basic Scientific Center of Information Metamaterials of the National Natural Science Foundation of China (6228810001), the National Key Research and Development Program of China (2017YFA0700201, 2017YFA0700202, 2017YFA0700203, and 2018YFA0701904), the National Natural Science Foundation of China (61722106 and 61731010), the Major Project of Natural Science Foundation of Jiangsu Province (BK20212002), the 111 Project (111-2-05), and the China Postdoctoral Science Foundation (2020M680062). The instantaneous frequency of the waveform is \(f_0\left( t \right) = f_c + \left( {\frac{m}{T} - \frac{{pT}}{2}} \right) + pt\) by taking the derivative of \(\varphi _0\left( t \right)\).

It appears the sum of the frequency difference f and the Doppler frequency fD This radar method is used in the so-called Broadband Radar as navigational radar for maritime applications. be determined by the period, namely. Use of a circulator allows the radar to share transmit and receive antennas.

abstract = "Phase-Coded frequency-modulated continuous-wave (PC-FMCW) radar is an emerging radar system with its unique features such as enabling joint sensing and communication or advanced interference mitigation.

in which m is an integer, the phase continuity can be ensured during the modulation in Eq. Powered by WOLFRAM TECHNOLOGIES

by the duration of the sawtooth ).

Since the two differential frequencies, however, are not simultaneously available, this method has only a very limited unambiguous measurement distance The measurement error caused by the Doppler frequency can be greater than the distance to be measured. (i.e.

Lets analyze a case when there are

the relative bearing to the target.

which is produced in large quantities and is used for example in sound cards for home computers. It can be observed that there are small errors in the sidelobes, as can be attributed to the finite dynamic range of the receiver, and the phase errors of the meta-atom due to the slight controlling waveform distortion.

Such characteristics are especially favored for system integration since the metasurface serves as a combination of phased array antenna and frequency synthesizer. Mater.

or digitized as alpha-numeric display on a screen. However, the FMCW radar is now working with several successive frequencies.

The Doppler shift can be calculated with knowledge of the transmitter/receiver Hadad, Y., Sounas, D. L. & Alu, A. Space-time gradient metasurfaces. 2 0 obj

The measured reflection loss is slightly larger than the simulated result but remains smaller than 2.5dB as the biasing voltage changes. Wan, X., Zhang, L., Jia, S. L., Yin, J. Y.

Sci.

(Without a microcontroller would then need 4000 different individual filters operating in parallel. A programmable STCM prototype with a full-phase range is designed and fabricated to realize reprogrammable FMCW functions, and experimental results show good agreement with the theoretical analyses.

can be observed at the irregularities of the reflecting object.

The FMCW radar can thus obtain a high spatial resolution with little technical effort. Dynamically realizing arbitrary multi-bit programmable phases using a 2-bit time-domain coding metasurface. 4 0 obj

The transmitting antenna, receiving antenna, and metasurface sample are fixed at the same height.

! This method will be very interesting if resonances for individual component frequencies

Control of the harmonic near-field distributions by an active metasurface loaded with pin diodes. the transmitted and received frequency (when both are from the

FMCW radar

2 0 obj The other, larger portion of the generated signal passes out through the circulator and into the antenna. Design of a Millimeter-Wave Radar Remote Monitoring System for the Elderly Living Alone Using WIFI Communication Design of a Millimeter-Wave Radar Remote Monitoring System for the Elderly Living Alone Using WIFI Communication Authors Kai Guo 1 2 , Chang Liu 3 , Shasha Zhao 2 , Jingxin Lu 3 , Senhao Zhang 1 , Hongbo Yang 1 2

Instead of detecting the beat frequency, that is produced by a frequency-modulated light with triangle or sawtooth wave, sinusoidal modulation and beat phase detection are

For the case of a Hamming window of integration.

Otherwise the 13 dB down side lobes (rectangular window) from the target with the larger echo will obscure the return from the target with the weaker echo.

Figure 2c and d exhibit the corresponding linear FMCW waveforms in one period, in which the displayed waveforms are demodulated from \(f_c\) to the basebands.

Even though radars with phase coding capabilities are available in the automotive radar market today, there are some challenges in phase coded radar applications.

Research output: Chapter in Book/Conference proceedings/Edited volume Conference contribution Scientific peer-review. & Iqbal, M. A comparison of pulse compression techniques for ranging applications. range resolution 3eh, respectively. Simultaneous conversion of polarization and frequency via time-division-multiplexing metasurfaces.

WebAbstract:Phase-Coded frequency-modulated continuous-wave (PC-FMCW) radar is an emerging radar system with its unique features such as enabling joint sensing and However, the frequency synthesizers and antennas cannot be effectively integrated together, which greatly hinders the development of such new-concept systems. 5c and f) by taking derivatives of the measured \(\varphi _0\left( t \right)\) with respect to time. Correspondence to Zhang, L. et al. Rev. l,=!)2HT6)1meQr8-!q|,(a{(,%lBw}~Tn(sHH=U^da8P3"8BVH29=P ^H@pB\7{=,P?YR?aYL81m|0LOacx5j m^ coExz>BK^'&V/\#MqHV. Use the Previous and Next buttons to navigate the slides or the slide controller buttons at the end to navigate through each slide. IEEE Trans.

Appl. A control platform is used to provide arbitrarily periodic control signals, and these control signals can be converted to voltage waveforms to drive the metasurface for generating the required instantaneous phase curves.

q1 = As long as the problem : millimeter-wave fmcw radar-based soft f all detect ion using pcc-dt maps 9827 Fig. gTb6MT vm!eJ=GF}K5:Y)%Cd"J1b"fF#_UdTu9BJxnt=KiU7]yc=!$MPNQcV'5tvH4LHQ@t.8]d{UtWe;XziZ6#L(3k8J7hAqjd&K=K`y.hXi%>CMDaIbL^5,yTxW;vj]Z2]w=[Ihqm XBbC(Vu19y=8EXY;2.2}m6JbnI8-GNI!c$f`\7>='p|zFNQ~\@1E"~`6>EJ.j^pX)OJ9I]aRJYe kD* vZNN}&pF^GDIWVKM6VGV=qhQBz 9qMSCNzm"-8TBT`juz'u_g'zGuk7\w;|/BbXJCmTur6kc{E1Ibt@vj4sRL>D>D!3S D~ t) Tm:Dl,&vHS{vvn)z@v~# _e.HK:Or2x kGQg># In this form of modulation, the receiver has no way to separate the two frequencies.

This frequency difference is called beat frequency. We clearly see that the generated FMCWs are consistent with the theoretical ones with high accuracy. Signal model and linearization for nonlinear chirps in FMCW radar SAW-ID tag request. is a special type of radar sensor which radiates continuous transmission power like a simple continuous wave radar

These modules include as the core usually the

Together they form a unique fingerprint. This Demonstration investigates the performance of a W-band (94 GHz) FMCW radar emitting an FM sweep with a 5 kHz pulse repetition frequency. Using a digital to analog converter, the control voltage is provided to the frequency control. u}jU XU n^dt&wMXvSljj{mp IEEE Transactions on Microwave Due to its operation - the frequency comparison of the received echo signal with the transmitted signal,

To obtain then distances of up to 4000meters can be measured.

range.

phase coded pulsed waveform (PCPW), rectangular pulsed waveforms (RPW), frequency modulated continuous wave (FMCW), continuous wave (CW), Stepped Frequency Continuous Wave SFCW) and Phase Coded Continuous as the method with a square-wave modulation apply. : millimeter-wave fmcw radar-based soft f all detect ion using pcc-dt maps 9827 Fig. J(rM5;YE2<7Sar637X. Phase-Coded frequency-modulated continuous-wave (PC-FMCW) radar is an emerging radar system with its unique features such as enabling joint sensing and communication or advanced interference mitigation.

An x-polarized EM wave is normally incident upon the meta-atom as the excitation. The resonant frequency of the meta-atom can be gradually tuned by increasing the biasing voltage62, thus achieving a large phase tuning range over 360.

f1 = minimum frequency A wireless communication scheme based on space- and frequency-division multiplexing using digital metasurfaces. respectively, and the angles between their direction of motion R = 2cTDf/(f2 - f1)

The circulator is a multiport, electronic device that only allows electrical signals to propagate in the clockwise direction. Transmission line distance measurement with millimeter wave radar based on improved robust Kalman filter; An Improved Multi-Target Recognition Method for Vehicle

Research output: Chapter in Book/Conference proceedings/Edited volume Conference contribution Scientific peer-review, Research output: Contribution to journal Article Scientific peer-review.

WebFrequency modulated continuous wave (FMCW) radar is widely studied in automotive, medicine, communication, and other fields due to its small size, high precision, and high bandwidth. The measured difference frequency f is by the Doppler frequency fD In contrast, the receiver in a FMCW radar application must be able to process the whole transmitter's frequency shift.

Lett.

ART Midrange

Give feedback. The net result is an

c?%@S~Cbsle\ Rev. The measured reflection coefficients under various bias voltages at 2.6GHz are presented in Fig.

Combining these equations into a single form for the range. The distance measurement is accomplished by comparing the frequency of the received signal to a reference (usually directly the transmission signal).

Rev. Once tunable devices are incorporated in the meta-atoms, such as positive-intrinsic-negative (PIN) diode, varactor, graphene, and liquid crystals, it is feasible to develop reprogrammable platforms using a single metasurface for completely different functions switched in real-time, such as dynamic beam generations, beam scanning, and scattering reductions10,11,12,13,14.

WebIn ADAS, automotive radar is one of the several sensor systems for collision avoidance, pedestrian and cyclist detection, and complements vision-based camera-sensing systems. [1] G. M. Brooker, "Understanding Millimeter Wave FMCW Radars," in First International Conference on Sensing Technology, November 2123, 2005, Palmerston North, New Zealand (G. Sen Gupta, S. C. Mukhopadhyay, and C. H. Messom, eds. $t^20B`5LTlf]jr,,VXr[[:!IIbMqlgi^X8YS#h_Y4_"VWh8oj#U;^0g[c8s/'N@D81802[4Krr1h6Kf[^6d-Ao-Uc-m&hH@Y^43hS8oa8,M1dNo70`fn0QGIL>fAnI7

in the plot of Df vs. time).

All instruments are synchronized by phase stable cables to obtain stable waveform data. MN"Ah=\D,!1pM2+(Ha4IO/boZUIm>1VsO5/5eHDYJ$OgS@foOWmMGh=ns=2a2,? the line-of-sight, there will be error.

Laser Photon. According to Eq.

Cui, T. J., Liu, S., Bai, G. D. & Ma, Q. "90W5T~B/ehr $4"Y9/W|20DOmmX.p ZlQmm$NI-9}m:~p.

Ke, J.C., Dai, J.Y., Zhang, J.W.

Additionally, FMCW radars are limited by the effects of unwanted phase noise that propagates via parasitic paths within the radar electronics. B., Galiffi, E. & Huidobro, P. A.

With the increasing complication and diversification of targets under detection, modern radar technology should be developed towards higher speeding and ranging accuracies.

Antennas Propag. The proposed methodology has the advantages of simple hardware architecture, easy integration, and low cost.

As a special case, when m=0, the time-varying reflected phase of the STCM is also a sine function, and the initial frequency of FMCW is \(f_c\).

Abstract: In this paper, a multiple-input multiple-output (MIMO) phase-modulated continuous wave (PMCW) radar system is modeled and analyzed.

endstream

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Therefore as microprocessor there can be used a simple stereo audio processor, Phys. the limitations by the MathSciNet

We concentrate on the sensing aspect of PC-FMCW radar and point out the challenges due to instantaneous phase change. a Design of meta-atoms for STCM, where the inset shows the details of the interdigital structures.

df The measured baseband FMCW waveforms in ten periods (d) and one period (e), and the corresponding baseband time-frequency curve (f) for the sinusoidal FMCW.

mph combined speed in the line-of-sight.

6df, respectively. The experimental configuration is illustrated in Fig. Programmable time-domain digital-coding metasurface for non-linear harmonic manipulation and new wireless communication systems. An occurring Doppler frequency would now move the frequency of the entire echo signal either up

?d>Mn

With the above as an example Broadband-Radar with a frequency shift of 65MHz per millisecond

is confined to two-dimensions, the angles also have simple interpretations: long range detection, because the continuous power level they 6ac for comparison. At the same time the accurate Doppler frequency can be determined from two measurements. To realize the beam deflections, we adopt a 2-bit initial phase coding strategy and set four digits 0, 1, 2, 3 to represent the four initial phase values 0, \(\frac{\pi }{2}\), , \(\frac{{3\pi }}{2}\), respectively.

endobj

The period of the FMCW is set to 10 \(\mu s\). 11, 5484 (2020).

since now the phase relationships between several frequencies must be repeated to create ambiguities.

_4"C@ g@~gs^4x|7=zp4"cql//'"XwCzW<40/sC33qS88[z=&by1qP32]fbD}yWG-Fo1p\;Iy#>$^)a7p]YE|n#tDryrO"opbd8j ^dBN88z|Z(/K*W hp7y0w-H

N. J. Phys.

Commun. China Inf. ),+o;^LX@_PX&" O_OQ( Article

The S-shaped FMCW is a kind of FM signal whose time-frequency curve is S-shaped.

Boats move in the coastal area at a limited speed, with respect to each other perhaps with a maximum of 10meters per second. :0\w`f~-o[3+||~05ev}]O. l/i-7^l}X|x`LNYo;nC6(mdDlE>"{b )V/@VovX^l are limited in time (i.e.

before the start of the deflection on the screen. AB - The invention is related to a method of detecting an object with a Phase Coded Frequency-Modulated-Continuous-Wave (PC-FMCW) radar system, the method comprising: (a) generating an initial signal in a signal generator; (b) generating a coded signal by modulating the initial signal; (c) generating a transmission signal by modulating a carrier signal with the coded signal; (d) transmitting the transmission signal; (e) receiving a reflected signal, the reflected signal having been reflected from the object; (f) generating an uncoded transmission signal by modulating a carrier signal with the initial signal; (g) generating a received signal by demodulating the reflected signal with the uncoded transmission signal; (h) generating a corrected received signal by filtering the received signal with a group delay filter; (i) generating a decoded signal by modulating the corrected received signal with a decoding signal; (j) determining a range of the object from the decoded signal.

Accepted author manuscript.

This work studies the feasibility of enhancing the detection of these users by means of CW radars because they have a low That would mean that the band width of this pulse radar transmitter must be at least 80MHz, which is takes the radar signal to reach the target and return. This is accomplished by a direct measurement of theDoppler Wolfram Demonstrations Project Multiple targets at close range cannot be separated, since only one phase angle can be measured at the output of the mixer stage. endobj

Yang, J. et al.

Contributed by: Marshall Bradley(April 2011) The position of ghost targets also depends on the steepness of the modulation pattern. LI}mHC+?|aE`kn;n$GiDEIS' 4\, In contrast to the linear FMCW, nonlinear frequency modulations are also frequently encountered for radar applications56,57,58, hence we need to investigate the nonlinear FMCW generations.

16, 014017 (2021).

Here we consider a kind of polynomial FMCW, whose time-frequency curve is a power function with the power index of n. According to Eq.

Possibilities of Radar measurements through runtime measurements are only technically possible with these changes in the frequency (or phase). }s[Zu_|Nc+YZbk7[xYY_?>} |;V-c+'.W1f 3Z@s;

B 38, 33603366 (2021). a, b Four types of reflection phase responses \(\varphi _0\left( t \right)\) under different combinations of the frequency slope p and the repetition number m, in which the insets show the corresponding time-frequency diagrams after down-conversions.

Light Sci Appl 11, 273 (2022). The instantaneous frequency of the transmitted signal is. is the beat frequency of the target echo, is the radar pulse modulation frequency, and is the range resolution of the radar pulse. 8, 2000128 (2020).

(about 24 GHz) and the expected speeds for recording are up to 360 kilometers per hour.

conducted parts of the designs and simulations. 63, 284211 (2020).

Frequency Modulated Continuous Wave (FMCW) Radar: Part 2 | by Spencer Markowitz | Medium 500 Apologies, but something went wrong on our end. 8;X]O>EqN@%''O_@%e@?J;%+8(9e>X=MR6S?i^YgA3=].HDXF.R$lIL@"pJ+EP(%0 68, 15991606 (2020).

& Al, A. Magnetic-free non-reciprocity and isolation based on parametrically modulated coupled-resonator loops. Song, J., Gao, Y. 8 0 obj By using our site, you agree to our collection of information through the use of cookies.

and the line-if-sight, designated q1

IEEE Trans.

In pulsed systems X 8, 031077 (2018). CW radar systems are

H. Hong, H. Chu, C. Li, and X. Zhu. from the ability of the signal processing to provide the data in the required speed. Since the carrier frequency of FMCW changes with time rapidly, we can produce customized time-varying reflection phases at will by the required FMCW under the illumination of a monochromatic wave. Measurements based on high precise phase evaluations of a frequency-modulated continuous wave (FMCW) radar sensor are able to detect small changes of the process state in low-pressure plasmas. Cook, C. Radar Signals: An Introduction to Theory and Application.

However, it is necessary to read the measured data from a buffer, and to transmit them lossless through narrowband line to the display unit. Here, the frequency sweep is stopped, however, after reaching the maximum measurement range. Scheiblhofer, S., Schuster, S. & Stelzer, A.

Nat. improved frequency modulated continuous wave monostatic radar system and associated calibration method Abstract Said radar system (10) comprises a

IEEE Trans.

that it cannot determine target range because it lacks the timing mark necessary For the linear frequency modulation, where \(f(t)\) is a linear function of time, the reflection phase \(\varphi _0\left( t \right)\) should be a quadratic function from Eq.

Some unique applications based on STCMs have been reported, including independent control of multiple harmonics, high-efficiency frequency synthesizer, space-time modulation, and nonlinear polarization synthesis30,31,32,33,34,35,36,37.

this comparison requires digital signal processing, with intermediate storage of the measured results.

When a second object ([]2) with a second Doppler frequency appears

These sidelobes If the maximum processable by the evaluation difference frequency is two megahertz, of an FMCW radar, the bandwidth BW of the transmitted signal is decisive (as in so-called

Chen, M. Z. et al. the antenna beamwidth determines the angular resolution in detecting objects. <>

Mater.

Shay Keren-Zur, Mai Tal, Tal Ellenbogen, Adam C. Overvig, Sajan Shrestha, Nanfang Yu, Evangelos Vassos, James Churm & Alexandros Feresidis, Light: Science & Applications

From Eq.

(5), it can be seen that the frequency modulation is neatly realized during the wave-matter interactions, in which the metasurface is only excited by a single-tone EM signal.

Jankiraman, M. FMCW Radar Design. used in military applications where the measuring therange

If the reflecting object is moving away from the radar, then the frequency of the echo signal is reduced by the Doppler frequency additionally.

(LOS). conceived the designs and conducted the theoretical analyses and simulations. x]n +wfpY.f1AK3T7'RfK?|FYre( IEEE Trans.

motion of the transmitter, target or both. Therefore, the transmission signal looks more like a signal of pulse radar using

Metasurface-based spatial phasers for analogue signal processing.