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Analysis of Time Diversity Gain for Satellite Communication Link based on Ku-Band Rain Attenuation Data Measured in Malaysia Islam Md. Rafiqul; Ali Kadhim Lwas; Mohamed Hadi Habaebi; Md Moktarul Alam; Jalel Chebil; Jit Singh Mandeep; Alhareth Zyoud
International Journal of Electrical and Computer Engineering (IJECE) Vol 8, No 4: August 2018
Publisher : Institute of Advanced Engineering and Science

This paper reports a study on mitigation of propagation impairments on Earth–space communication links. The study uses time diversity as a technique for mitigating rain propagation impairment in order to rectify rain fade. Rain attenuation time series along earth-to-satellite link were measured for two years period at 12.255 GHz in Malaysia. The time diversity technique was applied on measured rain fade to investigate the level of possible improvement in system. Time diversity gain from measured one-minute rain attenuation for two years period was estimated and significant improvement was observed with different delays of time. These findings will be utilized as a useful tool for link designers to apply time diversity as a rain fade mitigation technique in Earth-satellite communications systems.

Effects of humidity on sand and dust storm attenuation predictions based on 14 GHz measurement Eltahir Idris Eltahir Mohamed; Elfatih A. A. Elsheikh; A. Awad Babiker; Islam Md. Rafiqul; Mohamad Hadi Habaebi; Aisha H. Abdulla; Elessaid Saad
TELKOMNIKA (Telecommunication Computing Electronics and Control) Vol 19, No 2: April 2021
Publisher : Universitas Ahmad Dahlan

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.12928/telkomnika.v19i2.18148

Several models were proposed to predict the attenuation of microwave signals due to sand and dust storms. Those models were developed based on theoretical assumptions like Rayleigh approximation, Mie equations or numerical methods. This paper presents a comparison between attenuation predicted by three different theoretical models with measured attenuation at 14 GHz. Dielectric constant of dust particles is one of the important parameter in prediction models. This constant is estimated from measured dust samples and is utilized for predictions. All models are found largely underestimating the measurement. Humidity is also monitored and has been observed higher during dust storm. Hence dielectric constants are re-estimated with relative humidity conditions using available conversion model. The prediction has a great impact of humidity and predicted attenuations are found much higher in humid than dry dust condition. However, all models underestimate the measurement even considering 100% of relative humidity. Hence it is recommended to investigate the models by considering humidity and other environmental factors that change during dust storm.

Multiband antenna using stacked series array for Ka-Band application Rauful Nibir; Islam Md. Rafiqul; Mohamed Hadi Habaebi; Sarah Yasmin; Naimul Mukit; Sarah Rafiq; Abdinasir S. O
Bulletin of Electrical Engineering and Informatics Vol 8, No 3: September 2019
Publisher : Institute of Advanced Engineering and Science

In this paper, a multiband stack series array antenna is designed in order to attain solutions for the future 28 GHz Ka-band application. Double layer substrate Technology is utilized to accomplish multiple resonant frequencies with higher data transfer capacities due to high bandwidth. The designed antenna is dependent on twofold layer consisting patches and resonators in different layers stacked together. The designed multiband antennas can resonate at single band of (28 GHz), dual band of (28 and 30 GHz) and triple band of (24.18, 26 and 28.453). The results achieved in the simulation are later fabricated and tested. The test result illustrates that the antennas have wide bandwidth, high gain and even higher efficiencies. All the proposed antenna configurations have demonstrated a decent possibility for 5G millimeter wave (mmwave) application.

Investigation of time diversity gain for earth to satellite link using rain rate gain Md. Moktarul Alam; Islam Md. Rafiqul; Khairayu Badron; Farah Dyana A. R.; Hassaan Dao; M. Rofiqul Hassan; Ali Kadhim Lwas
Bulletin of Electrical Engineering and Informatics Vol 8, No 3: September 2019
Publisher : Institute of Advanced Engineering and Science

The utilization of satellites for communication systems has expanded considerably in recent years. C and Ku-bands of frequencies are already congested because of high demand. Future directions of satellite communications are moving towards Ka and V-bands. Earth to satellite communications are moving towards higher frequency bands in future which are more sensitive to environment. Rain causes severe degradation in performances at higher frequency bands specially in tropical regions. Several mitigation techniques are proposed to design reliable system. Time diversity is one of the potential candidate for it. However, time diversity analysis requires measured rain attenuation data. For future high frequency link design those data are not available at most of the places. This thesis proposes a method to utilize 1-minute rain rate to analyze time diversity technique at any desired frequency. This paper proposes a method to utilize 1-minute rain rate to analyse time diversity rain rate gain. In proposed method, it is assumed that rain rate gain with delay can represent rain attenuation gain with delay for same period of time at same location. The characteristics of rain rate and rain attenuation almost same because the attenuation causes due to rain. One year measured rain rate in Malaysia is used to predict rain rate gain. The measured gain at 12.225 GHz signal is compared with that predicted by ITU-R based on rain rate measurement and is found good agreement. Hence it is recommended that the time diversity gain can be predicted using measured rain rate for any desired frequencies.

Analysis of airborne dust effects on terrestrialmicrowave propagation in arid area Elfatih A. A. Elsheikh; Islam Md. Rafiqul; Mohamad Hadi Habaebi; Ahmad F. Ismail; Z. E. O. Elshaikh; F. M. Suliman; Jalel Chebil
Bulletin of Electrical Engineering and Informatics Vol 8, No 3: September 2019
Publisher : Institute of Advanced Engineering and Science

Sand and dust storms are environmental phenomena ,during these storms optical visibility might be decreased, consequently, atmospheric attenuation is clearly noticed.Micro-wave (MW) and Milimeter-wave (mm) propagation is severely affected by dust and sand storms in considerable areas around the world. Suspended dust particles may directly cause attenuation and cross polarization to the Electromagnetic waves propagating through the storm. In this paper, a thorough investigation of dust storm characteristics based onmeasured optical visibility and relative humidity is presented. In addition,the dust storms effects of on Micro-wave and Millimeter-wave propagation have been studied based on data measured Received Signal levels (RSL)and dust storm characteristics synchronously. Analyticaldustattenuationmodels predictions are matched to the measured attenuationdata at 14 GHz and 21 GHz. It has been found that the measured attenuation is approximately ten times higher than the predicted attenuation for both frequencies.

Investigation of time diversity gain for earth to satellite link using rain rate gain Md. Moktarul Alam; Islam Md. Rafiqul; Khairayu Badron; Farah Dyana A. R.; Hassaan Dao; M. Rofiqul Hassan; Ali Kadhim Lwas
Bulletin of Electrical Engineering and Informatics Vol 8, No 3: September 2019
Publisher : Institute of Advanced Engineering and Science

The utilization of satellites for communication systems has expanded considerably in recent years. C and Ku-bands of frequencies are already congested because of high demand. Future directions of satellite communications are moving towards Ka and V-bands. Earth to satellite communications are moving towards higher frequency bands in future which are more sensitive to environment. Rain causes severe degradation in performances at higher frequency bands specially in tropical regions. Several mitigation techniques are proposed to design reliable system. Time diversity is one of the potential candidate for it. However, time diversity analysis requires measured rain attenuation data. For future high frequency link design those data are not available at most of the places. This thesis proposes a method to utilize 1-minute rain rate to analyze time diversity technique at any desired frequency. This paper proposes a method to utilize 1-minute rain rate to analyse time diversity rain rate gain. In proposed method, it is assumed that rain rate gain with delay can represent rain attenuation gain with delay for same period of time at same location. The characteristics of rain rate and rain attenuation almost same because the attenuation causes due to rain. One year measured rain rate in Malaysia is used to predict rain rate gain. The measured gain at 12.225 GHz signal is compared with that predicted by ITU-R based on rain rate measurement and is found good agreement. Hence it is recommended that the time diversity gain can be predicted using measured rain rate for any desired frequencies.

Multiband antenna using stacked series array for Ka-Band application Rauful Nibir; Islam Md. Rafiqul; Mohamed Hadi Habaebi; Sarah Yasmin; Naimul Mukit; Sarah Rafiq; Abdinasir S. O
Bulletin of Electrical Engineering and Informatics Vol 8, No 3: September 2019
Publisher : Institute of Advanced Engineering and Science

In this paper, a multiband stack series array antenna is designed in order to attain solutions for the future 28 GHz Ka-band application. Double layer substrate Technology is utilized to accomplish multiple resonant frequencies with higher data transfer capacities due to high bandwidth. The designed antenna is dependent on twofold layer consisting patches and resonators in different layers stacked together. The designed multiband antennas can resonate at single band of (28 GHz), dual band of (28 and 30 GHz) and triple band of (24.18, 26 and 28.453). The results achieved in the simulation are later fabricated and tested. The test result illustrates that the antennas have wide bandwidth, high gain and even higher efficiencies. All the proposed antenna configurations have demonstrated a decent possibility for 5G millimeter wave (mmwave) application.

Analysis of airborne dust effects on terrestrialmicrowave propagation in arid area Elfatih A. A. Elsheikh; Islam Md. Rafiqul; Mohamad Hadi Habaebi; Ahmad F. Ismail; Z. E. O. Elshaikh; F. M. Suliman; Jalel Chebil
Bulletin of Electrical Engineering and Informatics Vol 8, No 3: September 2019
Publisher : Institute of Advanced Engineering and Science

Sand and dust storms are environmental phenomena ,during these storms optical visibility might be decreased, consequently, atmospheric attenuation is clearly noticed.Micro-wave (MW) and Milimeter-wave (mm) propagation is severely affected by dust and sand storms in considerable areas around the world. Suspended dust particles may directly cause attenuation and cross polarization to the Electromagnetic waves propagating through the storm. In this paper, a thorough investigation of dust storm characteristics based onmeasured optical visibility and relative humidity is presented. In addition,the dust storms effects of on Micro-wave and Millimeter-wave propagation have been studied based on data measured Received Signal levels (RSL)and dust storm characteristics synchronously. Analyticaldustattenuationmodels predictions are matched to the measured attenuationdata at 14 GHz and 21 GHz. It has been found that the measured attenuation is approximately ten times higher than the predicted attenuation for both frequencies.

Investigation of time diversity gain for earth to satellite link using rain rate gain Md. Moktarul Alam; Islam Md. Rafiqul; Khairayu Badron; Farah Dyana A. R.; Hassaan Dao; M. Rofiqul Hassan; Ali Kadhim Lwas
Bulletin of Electrical Engineering and Informatics Vol 8, No 3: September 2019
Publisher : Institute of Advanced Engineering and Science

The utilization of satellites for communication systems has expanded considerably in recent years. C and Ku-bands of frequencies are already congested because of high demand. Future directions of satellite communications are moving towards Ka and V-bands. Earth to satellite communications are moving towards higher frequency bands in future which are more sensitive to environment. Rain causes severe degradation in performances at higher frequency bands specially in tropical regions. Several mitigation techniques are proposed to design reliable system. Time diversity is one of the potential candidate for it. However, time diversity analysis requires measured rain attenuation data. For future high frequency link design those data are not available at most of the places. This thesis proposes a method to utilize 1-minute rain rate to analyze time diversity technique at any desired frequency. This paper proposes a method to utilize 1-minute rain rate to analyse time diversity rain rate gain. In proposed method, it is assumed that rain rate gain with delay can represent rain attenuation gain with delay for same period of time at same location. The characteristics of rain rate and rain attenuation almost same because the attenuation causes due to rain. One year measured rain rate in Malaysia is used to predict rain rate gain. The measured gain at 12.225 GHz signal is compared with that predicted by ITU-R based on rain rate measurement and is found good agreement. Hence it is recommended that the time diversity gain can be predicted using measured rain rate for any desired frequencies.

Multiband antenna using stacked series array for Ka-Band application Rauful Nibir; Islam Md. Rafiqul; Mohamed Hadi Habaebi; Sarah Yasmin; Naimul Mukit; Sarah Rafiq; Abdinasir S. O
Bulletin of Electrical Engineering and Informatics Vol 8, No 3: September 2019
Publisher : Institute of Advanced Engineering and Science

In this paper, a multiband stack series array antenna is designed in order to attain solutions for the future 28 GHz Ka-band application. Double layer substrate Technology is utilized to accomplish multiple resonant frequencies with higher data transfer capacities due to high bandwidth. The designed antenna is dependent on twofold layer consisting patches and resonators in different layers stacked together. The designed multiband antennas can resonate at single band of (28 GHz), dual band of (28 and 30 GHz) and triple band of (24.18, 26 and 28.453). The results achieved in the simulation are later fabricated and tested. The test result illustrates that the antennas have wide bandwidth, high gain and even higher efficiencies. All the proposed antenna configurations have demonstrated a decent possibility for 5G millimeter wave (mmwave) application.

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