Southern polar cap DPS and CADI ionosonde measurements. II - F-region drift comparison

Digisonde Portable Sounder 4 (DPS-4) and Canadian Advanced Digital Ionosonde (CADI) digital ionosondes were operated concurrently at the polar cap station Casey (110.5E, 66.3S geographic, 81.0S magnetic), Antarctica during 2000- 2001. These two digital ionosondes employ different antenna arrays and digital signal processing techniques, yet nevertheless are closely related instruments. An interleaved operation schedule permitted concurrent recording of ionograms and E- and F-region ionospheric drift measurements. This paper presents observations of background ionospheric drift in the F-region polar cap ionosphere using these two different digital ionosondes. A preliminary comparison between DPS and CADI drift measurements revealed substantial differences between the vertical (Vz) and horizontal (Vh) drift velocities determined by the two digital ionosondes. The DPS has since been relocated to the polar cusp station Davis (78.0E, 68.6S geographic, 74.6S magnetic), Antarctica.