Abstract:
Dust storms are significant meteorological phenomena which occur for a percentage of time in arid and semi-arid areas especially at African and Middle East, and this phenomena effect of signal attenuation signal level especially at Ku band and higher frequency with direct impact on telecommunications system performance
A study on dust storm effect on Microwave links in arid area covering a wide range of radiofrequency especially in 18GHz was running in Khartoum, Sudan. The study used Management system (computerized system) to monitoring Transmitted and Received Signal levels of one Microwave links operating at (18GHz) as well as an automatic weather station at Khartoum international airport for data collection concerning the effect of dust storm on signal attenuation. This data describe measurement results and reports for dust storms as they affect the radio wave propagation specially frequencies above 10GHz. The effect of dust storms on propagation is studied by measuring the storm parameters, visibility and attenuation due to these storms. The measurement results have been compared with the attenuation prediction models like Elshaikh and Goldhirsh Model. The estimation of these models are under the real measured estimations.
Few prediction models have been developed to calculate the attenuation due to dust storm in dB/km. All prediction models have assumed that the intensity of dust storm is uniformly distributed around the area covered by the dust storm.
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However, real dust storm is a complex phenomenon which is difficult to be described by theoretical physical or mathematical models .moreover these models did not suggested or built ascertain system to get rid of dust storm attenuation effect.in this work an electronic circuit together with software program was designed and used to get rid of signal attenuation. This system read the received signal level is beyond the threshold level, it stimulates the transmitter to readjust itself till the received signal level reaches or become above the threshold level. The experimental test of this system shows that it succeeded getting rid of attenuation.
