FMCW SAR THESIS

A combination of frequency-modulated continuous-wave FMCW technology with synthetic aperture radar SAR principles is a highly sought after method as it leads to a compact and cost effective high resolution near distance imaging system. To demonstrate the effectiveness and versatility of the proposed signal processing procedure, an S-band FMCW radar system, using off-the-shelf components, is designed for near distance target imaging using linear and circular SAR techniques. A signal processing procedure with system calibration methods to mitigate the effects of deramp, phase noise and nonlinearity of the VCO on the beat spectrum is proposed. As in conventional pulse SAR systems, the stop-and-go approximation could be used; such an approximation assumes the radar platform stationary during the transmission of the electromagnetic pulses and the reception of the corresponding echoes. Subject sar radar fmcw To reference this document use: However, the practical feasibility of an airborne FMCW SAR was not evident; the experimental sensors described in literature were, in fact, radars mounted on rail supports operating in ground SAR configurations and at short distances. Skip to main content.

Furthermore, such sensors are of military interest; reconnaissance tasks could be performed with small unmanned aerial vehicles UAVs , reducing in this way the risk for one’s own troops. Electrical Engineering, Mathematics and Computer Science. The novel combination of FMCW technology and SAR techniques leads to the development of a small, lightweight and cost-effective high resolution imaging sensor. Subject sar radar fmcw To reference this document use: Moreover, to be of interest for the civil market, cost effectiveness is mandatory. One of the limiting factors of FMCW radars is that the ramp signal modulates the received signal, which limits the minimum achievable range resolution.

The author has developed a very novel processing solution, which completely solves the problem of the presence of frequency non-linearities in FMCW SAR. Also the concept of synthetic aperture with FMCW sensors has already been put forward in literature, and some experimental systems have been described.

In practical FMCW sensors, specially when using cheap components, the presence of unwanted non-linearities in fmce frequency modulation severely degrades the radar performances for thesia distances.

A signal processing procedure with system calibration methods to mitigate the effects of deramp, phase noise and nonlinearity of the VCO on the beat spectrum is proposed. Skip to main content.

  KRISHNASHTAMI ESSAY IN TELUGU

fmcw sar thesis

Consequently, FMCW radar technology is of interest for civil and military airborne earth observation applications, specially in combination with high resolution Synthetic Aperture Radar SAR techniques. To resolve these issues, a multitude of hardware and software approaches have been proposed for the suppression of phase noise and nonlinearity of the transmitted signal.

In order to be operated from small, even unmanned, aircrafts, such systems must consume little power and be small enough to fulfill the usually strict payload requirements. The proposed method operates directly on the deramped data and it is very computationally efficient. One of the limiting factors of FMCW radars is that the ramp signal modulates the received signal, which limits the minimum achievable range resolution. The reconstructed images show the improvement of image quality and accuracy in the target position.

This thesis, or any portion thereof, may not otherwise be copied or reproduced without the written consent of the copyright owner, except to the thessi permitted by Canadian copyright law. SAR techniques have been successfully applied in combination with coherent pulse radars. The novel combination of FMCW technology and SAR techniques leads thesiw the development of a small, lightweight and cost-effective high resolution imaging sensor.

A combination of frequency-modulated continuous-wave FMCW technology with synthetic aperture radar SAR principles is a highly sought after method as it leads to a compact and cost effective high resolution near distance imaging system. Moreover, to be of interest for the civil market, cost effectiveness is mandatory.

Signal processing of FMCW Synthetic Aperture Radar data

For airborne FMCW radars, however, the stop-and-go approximation can be not valid anymore because the platform is actually moving while continuously transmitting. Additionally, the effect of bandwidth, integration angle and phase noise of the received pulses on the SAR image resolution in both range and cross-range directions are comprehensively studied.

Again, proper processing methods to overcome such limitation due to frequency non-linearities were not available to the scientific community.

fmcw sar thesis

The results were very successful. To improve the range accuracy, different calibration methods are also comprehensively studied. In the field of airborne earth observation there is special xar to compact, cost effective, high resolution imaging sensors.

fmcw sar thesis

To demonstrate the effectiveness and versatility of the proposed signal processing procedure, an S-band FMCW radar system, using off-the-shelf components, is designed for near distance target imaging using linear and circular SAR techniques. They consume little power and, due to the fact that they are sarr operating, they can transmit a modest power, which makes them very interesting for military operations.

  EUROPEAN CURRICULUM VITAE FORMAT BOSANSKI

FMCW-SAR System For Near Distance Imaging Applications

In addition, the voltage controlled oscillator VCO adds a certain degree of phase noise and nonlinearity to the transmitted signal that degrades the signal-to-noise ratio SNRrange accuracy and image resolution.

Finally, several avenues of further study and applications are suggested. A flight asr campaign has been organized during the last part of Within the framework of the project, the swr novelties and main results have been reached and are presented in the thesis: As in conventional pulse SAR systems, the stop-and-go approximation could be used; such an approximation assumes the radar platform stationary during the transmission of the electromagnetic pulses and the reception of the corresponding echoes.

This work seeks to overcome the three design issues mentioned above through the development of simulation platforms, which has been shown to be well-suited for the comprehensive study of these effects. Such sensors are foreseen to play an important role in small-scale remote sensing applications, such as the monitoring of dikes, watercourses, or highways.

FMCW-SAR System For Near Distance Imaging | ERA

It corrects for the non-linearity effects for the whole range profile at once, and it allows a perfect range focussing, independently of the looking angle. Electrical Engineering, Mathematics and Computer Science. Furthermore, such sensors are of military interest; reconnaissance tasks could be performed with small unmanned aerial vehicles UAVsreducing in this way the risk for one’s own troops.

However, the practical feasibility of an airborne FMCW SAR was not evident; the experimental sensors described in literature were, in fact, radars mounted on rail supports operating in ground SAR configurations and at short distances.