Deconvolution of Long-Pulse Lidar Profiles [chapter]

Ljuan L., Tanja N., Dimitar V.
2011 Lasers - Applications in Science and Industry  
Lasers -Applications in Science and Industry 250 And Ranging) (Gurdev et al., 2007a (Gurdev et al., , 2007b Dreischuh et al., 2007) where, because of the absence of short-pulse gamma ray lasers, the δ-pulse sensing procedure is based on the use of electron-positron annihilation-due gamma-photon pairs. At the same time, there exist some "software" approaches to improving the resolution and accuracy of the lidars. One of them consists in the use of deconvolution techniques (algorithms) for
more » ... ing the short-pulse lidar profiles on the basis of the measured longpulse lidar profiles and known sensing pulse shape (Gurdev et al.. Specific approaches have also been developed to improving the resolution of coherent heterodyne pulsed Doppler lidars (Gurdev et al., , 2002 (Gurdev et al., , 2003 (Gurdev et al., , 2008a . Mention as well an original and effective approach to achieving lidar-signal sampling intervals shorter than the data acquisition step based on the random delay of the sensing laser shots with respect to the ADC start pulses (Stoyanov et al., 2004 (Stoyanov et al., , 2010 . The purpose of the present chapter is to give a brief review of the works and to generalize the results obtained there about the advantages and limitations of some above-mentioned software approaches to improving the resolution and the accuracy of different TOF-based (lidar type) sensing methods. The first circle of problems considered is devoted mainly to deconvolution techniques for improving the resolution of long-pulse elastic lidars for sensing the atmosphere. The features are marked of Fourier and Volterra deconvolution algorithms at different levels and types of the measurement noise, and different types of uncertainties of the sensing laser pulses. The well-defined pulses of special concrete shape obtained by pulse-shaping are also of interest because they allow the design of special effective deconvolution algorithms. Here we also briefly describe a double-sided linearstrategy variant of lidar-type optical tomography. The following topic of interest concerns a novel (center-of-mass wavelength) Thomson scattering lidar method for measuring electron temperature profiles in thermonuclear plasmas (Gurdev et al., 2008b ; Dreischuh e t a l . , 2 0 0 9 ) a s w e l l a s s o m e r e c e n t r e s u l t s a b o u t t h e F o u r i e r -d e c o n v o l u t i o n d u e improvement of the sensing accuracy and resolution in this case. The concluding part of the chapter contains a brief discussion of the investigations described and the results obtained as well as of the importance of the software approaches to improving the lidar sensing accuracy and resolution.
doi:10.5772/24134 fatcat:kf6cme44yba6dlokoheckoxmdy