When a rectangular optical pulse is applied to the ofsl, a frequencystepped optical signal can be generated. Evaluation of millimeter wave radar using stepped multiple. Microdoppler effect analysis and feature extraction in isar. Stepped frequency radar is a prominent example of the class of continuouswave radar systems. Steppedfrequency pulse train waveforms for improved radar. Steppedfrequency radar is a prominent example of the class of continuouswave radar systems. Digital waveform control gives the radar the ability to avoid interference with other. In stepped frequency radar, a waveform is composed of multiple tones, or waveform segments, that are synthesized from a common stable oscillator and thus coherently related. The transmitted carrier frequencies are stepped n times in one sequence and the same sequences are repeated m. Antenna as a key component of radar directly related to the performance of the radar. The present invention uses a frequency modulation continuouswave fmcw or stepped frequency waveform and is capable of detecting nearrange targets that would normally be obscured by transmitter leakage and internal reflections. The radar measures the phase and amplitude on each frequency and used an inverse fourier transform of these data to build a time domain profile ascan.
Theory, analysis and design springerbriefs in electrical and computer engineering. Radar pulse compression using stepped frequency train of pulses free download as powerpoint presentation. The microdoppler md effect induced by the rotating parts or vibrations of the target provides a new approach for target recognition. In section 2, the frequencystepped chirp signal and the principle of the synthetic high range resolution are brie. Nonimaging fmcw radar characteristic of fmcw radar is. Steppedfrequency radar sensors are attractive for various sensing applications that require fine resolution. As part of grant 97ijcxk0 from the national institute of justice, akela, inc. Then,someaspectsofthechirpfrequencystepped signal are discussed. To reconstruct the rangedoppler information in a rsfr, previous studies based on sparse recovery mainly exploit the sparsity of the target scene. A stepped frequency cw sar for lightweight uav operation. The radar using stepped multiple frequency cpc sends and receives cpc pulses. The highresolution, frequencystepped chirp signal can be applied to radar systems employing narrowbandwidth chirp pulses, in order to enhance the range resolution, and to implement sarisar imaging capabilities. The authors are with the radar remote sensing group. Step frequency is a radar waveform consisting of a series of sine waves with linearly increasing frequency.
Penetration with step frequency ground penetrating radar. A steppedfrequency cw radar incorporates an rf source or a direct digital synthesis dds source, and dsp. Steppedfrequency radar design and signal processing enhances. A study on stepped frequency radar by using intrapulse. Range and velocity estimation of moving targets using conventional steppedfrequency pulse radar may suffer from the rangedoppler coupling and the phase wrapping. Continuouswave steppedfrequency radar for target ranging. Since raw data are recorded in frequencydomain direct investigations referring to the. Lord aspects of steppedfrequency processing for lowfrequency sar systems. The optimization technique is intended to maximize the target range resolution achievable from any set of frequencystepped cw radar measurements made in such an environment. R from radar, and r is assumed to satisfy 2rc stepped frequency radar with sparse recovery tianyao huang, yimin liu, huadong meng, xiqin wang abstract random stepped frequency rsf radar, which transmits random frequency pulses, can suppress the range ambiguity, improve convert detection, and possess excellent electronic countercountermeasures eccm ability 1. Pdf the steppedfrequency radar signal is revisited. Instantaneous, steppedfrequency, nonlinear radar request pdf. To overcome these problems, this paper presents a new radar waveform named multiple steppedfrequency pulse trains and proposes a.
Download it once and read it on your kindle device, pc, phones or tablets. Similar to linear fm pulse waveforms, stepped frequency waveforms are a popular pulse compression technique. Aspects of radar imaging using frequencystepped chirp signals. Radar pulse compression using stepped frequency train of. A photonic method for multioctave and reconfigurable frequencystepped radar waveform generation is proposed and experimentally demonstrated based on an optical frequency shifting loop ofsl. Us6664920b1 nearrange microwave detection for frequency.
A 65 nm cmos transmitter capable of providing signals over the wide 2 to 16 ghz frequency range for stepped frequency continuous wave shortrange medical radar applications is presented. Optimal signal processing of frequencystepped cw radar data. Pdf steppedfrequency pulsetrain radar signal researchgate. The distance measurement is accomplished by comparing the frequency of the received signal to a reference usually directly the transmission signal.
Steppedfrequency radar sensors theory, analysis and. The processing is a combination of two highresolution processes. Since raw data are recorded in frequency domain direct investigations referring to the frequency content can be done on the raw data. A phase modulator 18 modulates those portion of the radio frequency signals 62 to be transmitted. Continuous wave radar an overview sciencedirect topics. A pulse having low peak power and long duration is require at transmitter for long range detection,and at output of receiver the pulse should have short. To obtain high range resolution for the extraction of the fine md signatures of an inverse synthetic aperture radar target, the steppedfrequency chirp signal sfcs is used to synthesize the ultrabroad bandwidth and reduce the requirement of sample rates. Penetration with step frequency ground penetrating radar p. Millimeter wave radar using stepped multiple frequency. This type of radar was selected due to its relatively waveform, i. Complete list of all doppler radar andor pulsed radar, of all steppedfrequency, continuouswave cw radar, of all ultrawide band uwb radar andor the combination of these intentional radiators and radiolocators. A cancellation technique embodied in a system and a radar signal processing method that is employed to detect nearrange targets. In the first part of this paper, the principle of the stepped multiple frequency cpc modulation is explained.
It consists of a low frequency, impulsebased ultrawideband uwb radar that uses 16 receivers with 2 transmitters at the ends of the 2 meterwide receive array that send alternating, orthogonal waveforms into the. Stepped frequency an overview sciencedirect topics. Using this approach enables you to increase the range resolution of. When a rectangular optical pulse is applied to the ofsl, a frequency stepped optical signal can be generated. Radar returns from prominent scatterers of various parts of the target will be processed and displayed. Advanced steppedfrequency gpr development advanced steppedfrequency gpr development alberti, giovanni 20000706 00. Osa multioctave and reconfigurable frequencystepped radar. Steppedfrequency cw radar for concealed weapon detection. The channel is assumed to be composed of abrupt changes in the reflection coefficient profile. Range and velocity estimation of moving targets using. Complete list of all doppler radar andor pulsed radar, of all stepped frequency, continuouswave cw radar, of all ultrawide band uwb radar andor the combination of these intentional radiators and radiolocators. Randomized stepped frequency radar rsfr is very attractive for tasks under complex electromagnetic environment. This is a request under the freedom of information act.
Ofdm coupled compressive sensing algorithm for stepped. The continuous wave pulse train consists of a series of single frequency pulses, each at a different frequency. Steppedfrequency cw radar for concealed weapon detection and. In this study a linear frequency modulated chirp signal is approximated using two steppedfrequency pulse train waveforms, a continuous wave pulse train and a linear frequency modulated pulse train. Multioctave and reconfigurable frequencystepped radar. Steppedfrequency radar sensors are attractive for various sensing. Stepfrequency is a radar waveform consisting of a series of sine waves with linearly increasing frequency. Aspects of radar imaging using frequencystepped chirp. Cmos stepped frequency radar transmitter matlab project. The frequency is increased from step to step by a fixed amount.
A stepped frequency cw sar for lightweight uav operation 22 4 rtompset092 unclassifiedunlimited unclassifiedunlimited there is some degradation in range resolution as the frequency thinning becomes more extreme. A 65 nm cmos transmitter capable of providing signals over the wide 2 to 16 ghz frequency range for steppedfrequency continuous wave shortrange medical radar applications is presented. Use features like bookmarks, note taking and highlighting while reading steppedfrequency radar sensors. Complete list of all doppler radar andor pulsed radar, of. Mar 2002 alan langman the design of hardware and signal processing for a stepped frequency continuous wave ground penetrating radar. Steppedfrequency radar sensors are attractive for various sensing applications that require fine resol. The synthesis bandwidth of the terahertz thz sf radar is 12 ghz, which are beneficial for high resolution imaging. R from radar, and r is assumed to satisfy 2rc download as powerpoint presentation. This paper analyzes the effect of moving targets on the synthetic highresolution range profile obtained using this signal waveform. The synchronous impulse reconstruction sire radar is a multipleinput, multipleoutput mimo radar system designed to detect landmines and improvised explosive devices ieds. The present invention uses a frequencymodulation continuouswave fmcw or stepped frequency waveform and is capable of detecting nearrange targets that would normally be obscured by transmitter leakage and internal reflections. Advanced steppedfrequency gpr development, proceedings of. A pulse having low peak power and long duration is require at transmitter for long range detection,and at output of receiver the pulse should have short width and high peak power is required to achieve.
The radar is digitally synthesized and controlled and has a range resolution of approximately 4. A wide band ground penetrating radar system 10 embodying a method wherein a series of radio frequency signals 60 is produced by a single radio frequency source 16 and provided to a transmit antenna 26 for transmission to a target 54 and reflection therefrom to a receive antenna 28. Us5499029a wide band stepped frequency ground penetrating. A 12 ghz steppedfrequency gpr prototype has been completely designed and built to test the above theories. Steppedfrequency groundpenetrating radar for detection. Furthermore, the outline of the radar with the stepped multiple frequency cpc modulation are described. Hamada proceedings of the world congress on engineering and computer science 2008 wcecs 2008, october 22 24, 2008, san francisco, usa isbn. Hindawi publishing corporation eurasip journal on applied signal processing volume 2006 aspects of radar imaging using frequency stepped chirp signals qun zhang 0 1 yaqiu jin 0 0 key laboratory of wave scattering and remote sensing information ministry of education, fudan university, shanghai 200433, china 1 the institute of telecommunication engineering, air force engineering university. Cmos stepped frequency radar transmitter matlab projects. Hindawi publishing corporation eurasip journal on applied signal processing volume 2006 aspects of radar imaging using frequencystepped chirp signals qun zhang 0 1 yaqiu jin 0 0 key laboratory of wave scattering and remote sensing information ministry of education, fudan university, shanghai 200433, china 1 the institute of telecommunication engineering, air force engineering university. Theory, analysis and design springerbriefs in electrical and computer engineering kindle edition by nguyen, cam, park, joongsuk, park, joongsuk. In this work, we selected the step frequency radar sfr, which was originally introduced in 2, as a nonrealtime timedomainre. Doppler radar, the change in frequency between the transmitted and returns signal is used to calculate object velocity. A monostatic amplitude and phase steppedfrequency radar approach have been proposed to detect small nonmetallic buried antipersonnel ap mines.
Stepped frequency radar sensors are attractive for various sensing applications that require fine resolution. A study on stepped frequency radar by using intrapulse phase. Ofdm coupled compressive sensing algorithm for stepped frequency ground penetrating radar a thesis presented by mohamed metwally to the faculty of the graduate college of the university of vermont in partial fulfillment of the requirements for the degree of master of science specializing in electrical engineering october, 2014. Steppedfrequency radar signal processing sciencedirect.
To obtain high range resolution for the extraction of the fine md signatures of an inverse synthetic aperture radar target, the stepped frequency chirp signal sfcs is used to synthesize the ultrabroad bandwidth and reduce the requirement of sample rates. Each of these transmitted tones lasts for a time duration t 1 that should be long enough for the receiver to capture all reflected signals from the scene, starting from the. The optimization technique is intended to maximize the target range resolution achievable from any set of frequency stepped cw radar measurements made in such an environment. In this study a linear frequency modulated chirp signal is approximated using two stepped frequency pulse train waveforms, a continuous wave pulse train and a linear frequency modulated pulse train. Microdoppler effect analysis and feature extraction in. Subject terms stepped frequency waveform, inverse synthetic aperture radar isar processing, high. Using this approach enables you to increase the range resolution of the radar without sacrificing target detection capability.
A photonic method for multioctave and reconfigurable frequency stepped radar waveform generation is proposed and experimentally demonstrated based on an optical frequency shifting loop ofsl. Due to the synthetic high range resolution in rsrfs, a target usually occupies a series of range cells and is called an extended target. We propose a method for synthesizing high range resolution profiles hrrp using stepped frequency waveform. Ofdm coupled compressive sensing algorithm for steppedfrequency ground penetrating radar a thesis presented by mohamed metwally to the faculty of the graduate college of the university of vermont in partial fulfillment of the requirements for the degree of master of science specializing in electrical engineering october, 2014.
A monostatic amplitude and phase stepped frequency radar approach have been proposed to detect small nonmetallic buried antipersonnel ap mines. Steppedfrequency processing by reconstruction of target. Steppedfrequency radar sensors theory, analysis and design. An m56 apmine with a diameter of 54 mm and height of 40 mm, only, has been successfully detected and located in addition to small metallic mineshaped objects. Steppedfrequency pulsetrain radar signal article pdf available in iee proceedings radar sonar and navigation 1496.
Twodimensional tm scattering problem where the 2d scatterer. A 12 ghz stepped frequency gpr prototype has been completely designed and built to test the above theories. Figure 4 shows the effect on the profile of a point target as the frequency spectrum is thinned to 50% and 70%. A study on stepped frequency radar by using intrapulse phase coded modulation c. Stepped frequency chirp signal sfcs, as an important signal form of sar imaging, has been used to achieve high resolution with low instantaneous bandwidth and low sampling rate, and has been paid more and more attention 16. Based on the analysis in chapter 3, for the radar with steppedfrequency chirp signal, the parameters rq.