Determination of Melting Layer Boundaries and Attenuation Evaluation in Equatorial Malaysia at Ku-Band

Abayomi Isiaka Yussuff, Nor Hisham Haji Khamis


Upsurge in bandwidth demand in recent times for real-time data transmission have put serious constraints on satellite communication channels, leading to congestion of the lower frequency bands; necessitating migration to higher bands (Ku, Ka and V) with attendant problems such as signal fading, depolarization and attenuation due to presence of hydrometeors. There is need to separately account for attenuation due to the melting layer along the earth-space microwave links. One year data from ground-based S-band meteorological radar sourced from Kluang station of the Malaysian Meteorological Department was processed to build the vertical reflectivity of rain profile for UTM, Malaysia. Results from this work suggested that the effects of the melting layer on signal attenuation at Ku-band can be quite significant in the tropical and equatorial regions. It was estimated to be 13.36 dB and 15.44 dB at 0.01% of the time exceeded using Laws-parsons and Marshall-Palmer regression coefficients, respectively. Furthermore, it was observed that ITU-R. P.618-11 model largely under-estimated the attenuation along the slant-paths because of its failure to account for attenuation due to the melting layer in its formulation by its assumption of constant rain rate; thus rendering it unsuitable for rain attenuation predictions in the tropics.


Break-point attenuation, Rain rates, Stratiform rain, Melting layer, 00C Isotherm height


Brown, S. T., Ruf, C. S. Validation and development of melting layer models using constraints by active/passive microwave observations of rain and the wind-roughened ocean surface, Journal of Atmospheric and Ocean Technology. 2007; 24: 543–563.

Klaassen, W. Radar observations and simulation of the melting layer of precipitation, Journal of the atmospheric sciences. 1988; 45(24): 3741-3753.

Klaassen, W. Attenuation and reflection of radio waves by a melting layer of precipitation, IEE Proceedings. 1990; 137H(I): 39-44.

ITU-R. P. 618-11, Propagation Data and Prediction Methods Required for the Design of Earth-Space Telecommunications Systems, Recommendation ITU-R P Series. Geneva: IEEE Press; 2013.

Dissanayake, A., Allnutt, J., Haidara, F. A prediction model that combines rain attenuation and other propagation impairments along earth-satellite paths, Antennas and Propagation, IEEE Transactions. 1997; 45(10): 1546-1558.

Botta, G., Aydin, K., Verlinde, J. Modeling of microwave scattering from cloud ice crystal aggregates and melting aggregates: A new approach, IEEE Geosci. and Remote Sens. Lett. 2010: 7: 572–576.

Lam, H. Y., Din, J., Capsoni, C., Panagopoulos, A.D. Stratiform and Convective rain Discrimination for Equatorial Region, Proceedings of 2010 IEEE SCOReD. 2010: 112-116.

Ajayi, G. O., Odunewu, P. A. Some Characteristics of the Rain Height in a Tropical Environment, Antennas and Propagation, 1989. ICAP 89, Sixth International Conference on (Conf. Publ. No. 301). IET, Coventry. 1989: 80-82.

Das, S., Maitra, A. (2011). Some melting layer characteristics at two tropical locations in Indian region, General Assembly and Scientific Symposium, 2011 XXXth URSI. IEEE. 2011: 1-4.

Konstantinos, P., Melina, I., Dimitrios, C. Comparison of radar reflectivity calculations to satellite measurements across the melting layer of precipitation, General Assembly and Scientific Symposium, 2011 XXXth URSI IEEE. 2011: 1-4.

Raymond, L. et al. Improved Modelling of Propagation and Backscattering of Millimeter waves in the Melting Layer, IEEE National Conference on Antennae and Propagation. 1999: 160-163.

Fabry, A. Bellon, Zawadzki, I. I. Long Term Observations of the Melting Layer Using Vertically Pointing Radars MW-101. Report. Vol. 65, McGill University, Canada. 1-65.1994.

Sarkar, T., Das, S., Maitra, A. Effects of melting layer on Ku-band signal depolarization, Journal of Atmospheric and Solar-Terrestrial Physics. 2014: 1-21.


Nebuloni, R., Capsoni, C. Laser attenuation by falling snow, Communication Systems, Networks and Digital Signal Processing, CNSDSP. 6th International Symposium. 2008: 265-269.

Olivier P., Frédéric M., Sauvageot, H. Effects of Melting Layer in Airborne Meteorological X-Band Radar Observations, IEEE Transactions on Geoscience and Remote Sensing. 2012; 50(6): 2318-2324.

Takahashi, N., Awaka, J. Introduction of a melting layer model to a rain retrieval algorithm for microwave radiometers, Geoscience and Remote Sensing Symposium, IGARSS'05 Proceedings. 2005; 5: 3404-3409.

Luini L., Capsoni, C. Performance Evaluation of Satellite Communication Systems Operating in the Q/V/W Bands. Report. Politecnico di Milano, Dipartimento di Elettronica e Informazione, Italy. 2-37. 2013.

Adetan, O., Afullo, T. J. Raindrop size distribution and rainfall attenuation modeling in equatorial and subtropical Africa: the critical diameters, Annals of telecommunications-annales des telecommunications. 2014: 1-13.

Adhikari, A., Bhattacharya, A., Maitra, A. Rain-induced scintillations and attenuation of Ku-band satellite signals at a tropical location, Geoscience and Remote Sensing Letters, IEEE. 2012; 9(4): 700-704.

Mandal, B. K., Bhattacharyya, D., Kang, S. Attenuation of Signal at a Tropical Location with Radiosonde Data Due to Cloud, International Journal of Smart Home. 2014; 8(1): 15-22.

Rahim, S. K. A., Rahman, T. A., Tan, K. G., Reza, A. W. Microwave signal attenuation over terrestrial link at 26 GHz in Malaysia, Wireless Personal Communications. 2012; 67(3): 647-664.

Bryant, G. H., Adimula, I., Riva, C., Brussaard, G. Rain attenuation statistics from rain cell diameters and heights, International journal of satellite Communications. 2001; 19(3): 263-283.

Ramachandran, V., Kumar, V. Modified rain attenuation model for tropical regions for Ku‐Band signal, International Journal of Satellite Communications and Networking. 2007; 25(1): 53-67.

Marshall, J. S., Palmer, W. M. K. The distribution of raindrops with size, Journal of meteorology. 1948; 5(4): 165-166.

Kozu, T., Reddy, K. K., Mori, S., Thurai, M., Ong, J. T., Rao, D. N., Shimomai, T. Seasonal and diurnal variation of raindrop size distribution in Asian monsoon region, Journal of Applied Meteor. Soc. Japan. 2006; 84A: 195–209.

Laws, J. O., Parsons, D. A. The Relationship of Raindrop Size to Intensity, Transactions - America Geophysical Union. 1943; 24: 452–460.

Zhang, W., Moayeri, N. Power-Law Parameters of Rain Specific Attenuation, Report, National Institute of Standards and Technology, IEEE, 1-8. 1999.

ITU-R. P.839-3. Rain height model for prediction methods, Recommendation ITU-R P Series. Geneva: IEEE Press; 2001.

Yussuff, A. I. O. Characterization of bright-band in a tropical station for satellite communications. Ph.D. Thesis. Dept. of Communications Engineering, Universiti Teknologi Malaysia. 2014.

ITU-R P.311-13. Acquisition, presentation and analysis of data in studies of tropospheric propagation, Recommendation, ITU-R Radio Propagation Series. Geneva: IEEE Press; 2009.

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