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A Novel Modified Omega-K Algorithm for Synthetic Aperture Imaging Lidar through the Atmosphere

View Article: PubMed Central

ABSTRACT

The spatial resolution of a conventional imaging lidar system is constrained by the diffraction limit of the telescope's aperture. The combination of the lidar and synthetic aperture (SA) processing techniques may overcome the diffraction limit and pave the way for a higher resolution air borne or space borne remote sensor. Regarding the lidar transmitting frequency modulation continuous-wave (FMCW) signal, the motion during the transmission of a sweep and the reception of the corresponding echo were expected to be one of the major problems. The given modified Omega-K algorithm takes the continuous motion into account, which can compensate for the Doppler shift induced by the continuous motion efficiently and azimuth ambiguity for the low pulse recurrence frequency limited by the tunable laser. And then, simulation of Phase Screen (PS) distorted by atmospheric turbulence following the von Karman spectrum by using Fourier Transform is implemented in order to simulate turbulence. Finally, the computer simulation shows the validity of the modified algorithm and if in the turbulence the synthetic aperture length does not exceed the similar coherence length of the atmosphere for SAIL, we can ignore the effect of the turbulence.

No MeSH data available.


Contour map of one point dimension
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f5-sensors-08-03056: Contour map of one point dimension

Mentions: Figures 5 and 6 show the contour maps of a point after and before the Doppler shift compensation respectively. Figure 5 shows the data processing after using the modified Omega-K algorithm, while Figure 6 represents the data processing after using the conventional Omega-K algorithm. We can see that the data defocus if the Doppler shift induced by the continuous motion of the platform in the sweeps is not compensated.


A Novel Modified Omega-K Algorithm for Synthetic Aperture Imaging Lidar through the Atmosphere
Contour map of one point dimension
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3675531&req=5

f5-sensors-08-03056: Contour map of one point dimension
Mentions: Figures 5 and 6 show the contour maps of a point after and before the Doppler shift compensation respectively. Figure 5 shows the data processing after using the modified Omega-K algorithm, while Figure 6 represents the data processing after using the conventional Omega-K algorithm. We can see that the data defocus if the Doppler shift induced by the continuous motion of the platform in the sweeps is not compensated.

View Article: PubMed Central

ABSTRACT

The spatial resolution of a conventional imaging lidar system is constrained by the diffraction limit of the telescope's aperture. The combination of the lidar and synthetic aperture (SA) processing techniques may overcome the diffraction limit and pave the way for a higher resolution air borne or space borne remote sensor. Regarding the lidar transmitting frequency modulation continuous-wave (FMCW) signal, the motion during the transmission of a sweep and the reception of the corresponding echo were expected to be one of the major problems. The given modified Omega-K algorithm takes the continuous motion into account, which can compensate for the Doppler shift induced by the continuous motion efficiently and azimuth ambiguity for the low pulse recurrence frequency limited by the tunable laser. And then, simulation of Phase Screen (PS) distorted by atmospheric turbulence following the von Karman spectrum by using Fourier Transform is implemented in order to simulate turbulence. Finally, the computer simulation shows the validity of the modified algorithm and if in the turbulence the synthetic aperture length does not exceed the similar coherence length of the atmosphere for SAIL, we can ignore the effect of the turbulence.

No MeSH data available.