Ionospheric Drift Measurements - Skymap Points Selection

We present analysis of ionospheric drift measurements in observatory Pruhonice (50.0N, 14.6E), where we regularly monitor state of the ionosphere by Digital Portable Sounder DPS 4. We apply a newly improved three-step selection process on skymap reflection points automatically produced by digisonde. To evaluate drift velocity we apply standard DDA method on the corrected skymaps. Our contribution describes step by step examples of a quality data control procedure for final drift velocity evaluation: (i) robust height range selection, (ii) setting limits on the Doppler frequency shift, and (iii) setting limits on the echo arrival angle. This selection method is applicable to both E and F-region drift measurements and guarantees a better quality of obtained drift velocities data and further interpretation of plasma motion.