Interpretation Procedure of Meteorological Radar Data for Propagation Application in Heavy Rain Region Hong Yin Lam 1 , Jafri Din 1 , and Siat Ling Jong 1, 2 1 Department of Communication Engineering, Faculty of Electrical Engineering, UTM, 81310 Skudai, Johor, Malaysia 2 Department of Communication Engineering, Faculty of Electrical and Electronic Engineering, UTHM, 86400, Parit Raja, Johor, Malaysia Abstract–Advanced satellite communication or modern wireless systems operate at high frequencies will suffer from deep signal fades caused by rain particularly in equatorial region. Meteorological radar operates by MET department is one of the valuable resources to provide the peculiarities of the local precipitation information oriented to the analysis of radio propagation impairments. In this paper, the processing methodology and the interpretation procedure of operational weather radar data are presented from the perspective of such application. The applicability of the processed meteorological radar data is preliminary assessed against Stratiform Convective-Synthetic Storm Technique (SC-SST) in terms of first order rain attenuation statistics. The radar data simulated statistic is found to agree well with the one obtained through SC-SST. This procedure can be useful as a reference methodology for the employment of operational meteorological radar particularly focus on the propagation applications. Index Terms —Diversity gain, Heavy rain region, Rain attenuation, Time diversity I. INTRODUCTION Modern satellite communication systems operate at high frequencies will suffer from deep signal fades due to rain particularly in equatorial region. Besides temporal characteristics, complex satellite propagation channel models require also the knowledge of spatial variability of the precipitation. To this aim, ground weather radar is a power source in providing finest spatial information of the rainfall horizontal structure from the hydrometeor observation as compared to satellite and Space-borne radar. In fact, weather radar is capable to offer considerable quantities of information on the three-dimensional structure of the precipitation. However, in order to produce reliable radar data for such propagation application, the capability for elaborate filtering and data handling as well as efficient processing techniques of complex weather data are required. In response to this need, this work describes the processing methodology and interpretation of large amounts of digitized reflectivity factor data for propagation applications. Section II briefly introduces the weather radar database used in this work. Afterwards, the procedure and processing flow of radar data is duly described in Section III. The processed database is preliminary validated in Section IV against the Synthetic Storm Technique, SC-SST [1] by assessing its validity in reproducing the firs-order rain attenuation statistics. Finally, Section V draws some conclusions. II. THE WEATHER RADAR DATA In this study, S-band weather radar managed by Malaysia Meteorological Department located at Kluang, Johor (latitude 2.02° N, longitude 103.3° E), Malaysia is employed. The database is extracted from January 2007 to December 2008 of continuous meteorological observation operation. The radar performing a volumetric scan (15 elevation angle :0.5°, 0.8°, 1.1°, 1.4°, 1.9°, 2.5°, 3.3°, 4.4°, 5.8°, 7.7°, 10.3°, 13.6°, 18.1°, 24.1° and 32.1°) at every 10 min with a complete azimuth scan which required 5 minutes of duration for a complete volumetric scan. The contiguous pulse volumes are sampled each 500m in range with a maximum radius of 250 km. [2]. III. METHODOLOGY OF RADAR DATA PROCESSING In order to obtain an informative radar images with details digital value of radar reflectivity, the raw radar data that are encoded in the form of ASCII asynchronous format are first decoded into the matrix array. Each elevation angle consists of 360 arrays of data, each one corresponding to one azimuth angle, with 16 quantization levels of radar reflectivity Z. The radius of the observation area has been limited to 50 km to limit the averaging effect inherently performed by weather radars as a result of beam broadening. After the decoding process, each volumetric scanned image consists of 15 elevation angles were subsequently remap to obtain pseudo CAPPI (Constant Altitude Plane Position Indicator) resulting from the composition of five elevation scans named 1.4°,1.9°,2.5°,3.3° and 4.4° at a constant plane of 1.5 km from ground as sketched in Fig.1. Each CAPPI image corresponding to the total scanned time of 1.5 minutes, in order to obtain the best spatial resolution with an almost instantaneous image of rain, while the radar data are kept at the constant height of 1.5 km above ground with aim to avoid FR3C_05 FR3C_05 FR3C_05 FR3C_05 Proceedings of ISAP 2014, Kaohsiung, Taiwan, Dec. 2-5, 2014 579