Proceedings with Extended Abstracts (single PDF file) - Radio ...

WIND AND TURBULENCE MEASUREMENTS BY THE MIDDLEAND UPPER ATMOSPHERE RADAR USING UCAR-STARS METHODAlexander Praskovsky 1 , Eleanor Praskovskaya 2 ,Gernot Hassenpflug 3 , Mamoru Yamamoto 3 , and Shoichiro Fukao 31 National Center for Atmospheric Research, 3450 Mitchell Lane, Boulder, CO 80301, USA2 Colorado Research Associates, 3380 Mitchell Lane, Boulder, CO 80301, USA3 Radio Science Center for Space and Atmosphere, Kyoto University, Uji, 611-0011, JapanSpaced antenna (SA) methods for analyzing complex time series of signals from multiplereceivers have become commonly used techniques for measuring parameters of theatmosphere from the lower troposphere up into the ionosphere. The most used methods areFull Correlation Analysis in the time domain, and Full Spectral Analysis in the frequencydomain (Briggs, 1984; and Briggs and Vincent, 1992). A structure function (SF)-basedapproach has been developed recently by Praskovsky and Praskovskaya (2003a, b), and thename UCAR-STARS (University Corporation for Atmospheric Research - STructurefunction Analysis of Received Signals) was coined to describe the data analysis techniquebased on this approach. The goal of this work is to evaluate the potential of STARS formeasuring mean horizontal winds and turbulence characteristics of a scattering medium withSA radars. The Middle and Upper Atmosphere radar (MUR) is one of the most powerful andflexible MST radars in the world, which makes it a natural test-bed for the method. TheHolloway and Doviak (HAD) correlation function (CF)-based SA method (Doviak et al.,1996, and Holloway et al., 1997) was chosen from a diversity of existing SA techniques fortesting STARS. Comprehensive description of this work including theoretical comparison ofSTARS and HAD and detailed analysis of experimental results for the MUR is presented inPraskovsky et al. (2003) while only a brief summary is given in this paper.The MUR is located in Shigaraki, Japan (34.85 o N, 136.10 o E) at approximately 1 km abovesea level. It is operated by the Radio Science Center for Space and Atmosphere of KyotoUniversity. MUR is an MST Doppler research radar with operational frequency 46.5 MHz. Itis an active phased array system, the radar's antenna consists of 475 crossed Yagis with theaperture of 8,330 m 2 (103 m in diameter); see Fukao et al. (1985a, b) for details.The data collection for testing UCAR-STARS was executed on 24 - 25 April 2002. Duringthe experiment, the radar was operated for 6.55 min. in the SA mode, then for 58.4 s in theDoppler Beam Swinging (DBS) mode; the sequence was continuously repeated for severalhours for each studied configuration of receiving antennas. Both in DBS and SA modes, afull antenna (475 Yagis) was transmitting at a pulse repetition frequency of 2,500 Hz. Therange resolution and the gate separation were 150 m; 64 gates covered a height z o from 5 kmto 15 km above the radar. In DBS mode, the pulses were transmitted in five directions, andthe full antenna was used to receive the signals. Different configurations of four receiverseach with an aperture of approximately 2,330 m 2 (133 Yagis) were studied in SA mode.152The mean horizontal wind speed components U (toward east) and V (toward north) wereretrieved from the MUR signals in the SA mode with STARS and HAD methods at the sameaveraging time T av = 78.6 s, which is close to the DBS T av = 58.4 s. A good agreement of theSTARS and HAD-produced mean winds with those produced by DBS was found at heightsfrom 5 km to approximately 11 km where signal-to-noise ratio (SNR) is rather high; typicaltime series are shown in Fig. 1. Above 11 km, where the SNR is low, the agreement is quite