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Usually, data obtained by ground penetrating radar (GPR) are displayed as a rectangular 2D picture (profile), vertical and horizontal axes of which are proportional to depth and traveled distance, respectively. Surface, generally, is not horizontal, that leads to distorted view of irregularities in the GPR profile. To eliminate these distortions a topographic correction is used. Topographic data can be obtained by laser leveler, total station, GPS and similar equipment. Further this information is used for topographic correction of the GPR data.This paper provides method of topographic correction based on information about traveled distance and tilt of antenna unit at each point of measurement. These data are measured by odometer and inclinometer, respectively. The information is obtained simultaneously with the GPR data and is connected with each trace of the profile. Algorithm of traces vertical offset calculation relatively the first trace of profile and accuracy of topographic correction are discussed. The results of topographic correction of profile acquired by VIY3-300 GPR are presented. This inexpensive solution improves performance characteristics of GPR and reduces time required for GPR profiles processing and their interpretation.

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Practical aspects of effective generation of short electromagnetic pulses (EMP) and improvement of radiation efficiency are discussed in this paper. Descriptions of the EMP radiation based on the Poynting vector definition and energy transformation are presented below. Antennas classification based on energy behavior in the radiating system is proposed and discussed. Properties of kinetic energy accumulated antennas are analyzed. To generate electromagnetic pulse the kinetic energy accumulated antenna is combined with such opening switch as drift step-recovery diode (DSRD). Operation principles of the DSRD are discussed. Criteria of diodes selection for its application in drift step-recovery (DSR) mode are proposed and described. Methods of provision the DSRD operation condition with a balanced current driver are developed and analyzed. A prototype of antenna-generator that utilizes proposed operation principles was designed, developed and examined. Waveform and power spectrum are presented. Peak power more than 1 kW was achieved on the antenna terminal with 3 ns pulse duration and up to 200 kHz pulse repetition frequency (PRF). The prototype's power consumption didn't exceed 4 W under 100 kHz PRF condition. The proposed approach allows producing of stable nanosecond electromagnetic impulses with hundreds kilowatts peak power and PRF up to hundreds kHz.