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Sains Malaysiana 48(1)(2019): 183–189
http://dx.doi.org/10.17576/jsm-2019-4801-21
Radio
Frequency Interference on Nearby Radio Astronomical Lines: Relationship between
Wind Speed and Radio Signal Strength Measured at East Coast of Peninsular
Malaysia
(Gangguan
Frekuensi Radio pada Talian Astronomi Radio Berdekatan: Hubungan antara
Kelajuan Angin dan Kekuatan Isyarat Radio Diukur di Pantai Timur Semenanjung
Malaysia)
SHARIFAH NURUL AISYAH SYED ZAFAR1, NOR HAZMIN SABRI2*, ROSLAN UMAR1 & ZAINOL ABIDIN IBRAHIM3
1East Coast
Environmental Research Institute (ESERI), Universiti Sultan Zainal Abidin, Gong
Badak Campus, 21300 Kuala Terengganu, Terengganu Darul Iman, Malaysia
2School
of Fundamental Science, Universiti Malaysia Terengganu, 21030 Kuala Terengganu,
Terengganu Darul Iman, Malaysia
3Physics
Department, Faculty of Science, Universiti of Malaya, 50603 Kuala Lumpur,
Federal Territory, Malaysia
Received:
28 March 2018/Accepted: 12 September 2018
ABSTRACT
The East coast of Peninsular Malaysia receives a strong wind
speed, heavy rain and high humidity during the Northeast monsoon. The Malaysian
Meteorological Department claims that the wind speed during the Northeast
season could reach 55.56 km/h or more. This strong wind speed and heavy rain could
contribute to the attenuation of radio signals. This paper investigated the
relationship between wind speed (km/h) and radio signal strength, RSS (dBm).
The statistical correlation was employed to identify the correlation value and
strength between them. The wind speed and RSS were
collected during wet and dry seasons at Kusza Observatory, while the Spectrum
analyser was used for measuring RSS (dBm) and the weather
station for wind speed (km/h). The result showed that the wet season has strong
and significant correlation compared to the dry season. Frequencies of 382.5
MHz, 945 MHz and 2160 MHz with correlation values of r = -0.583;-0.631 and -0:514,
respectively, showed strong, negative and significant correlations with wind
speed in the wet season. As for the dry season, only a frequency of 382.5 MHz
showed a strong, positive and significant correlation with r = 0.555, while
small and medium for others. This finding is useful to a radio astronomer to
help determine the best period for radio astronomy observation with the lowest
interference considering the weather in the East Coast of Peninsular Malaysia.
Besides, this finding benefits a spectrum of users involved in mobile
telecommunication, wireless internet, radio TV transmission
and satellite broadcasting.
Keywords: Correlation; radio signal attenuation; radio signal
strength; wind speed
ABSTRAK
Pantai Timur Semenanjung Malaysia menerima kelajuan angin yang
kuat, hujan lebat dan kelembapan yang tinggi semasa monsun Timur Laut. Jabatan
Meteorologi Malaysia menyatakan bahawa kelajuan angin semasa musim Timur Laut
boleh mencapai 55.56 km/jam atau lebih. Kelajuan angin yang kuat dan hujan lebat
ini menyumbang kepada pengurangan isyarat radio. Dalam kajian ini, kami
mengkaji hubungan antara kelajuan angin (km/jam) dan kekuatan isyarat radio, RSS (dBm).
Korelasi statistik digunakan untuk mengenal pasti nilai korelasi dan kekuatan
antara kedua-dua faktor itu. Kelajuan angin dan RSS direkodkan
pada musim lembab dan kering di Kusza Observatori sementara penganalisis
spektrum digunakan untuk pengukuran RSS (dBm) dan alat stesen cuaca
untuk kelajuan angin (km/jam). Keputusan kajian musim lembab menunjukkan
korelasi yang kuat dan ketara berbanding musim kering. Frekuensi 382.5 MHz, 945
MHz dan 2160 MHz menunjukkan korelasi yang kuat negatif dan signifikan dengan
kelajuan angin dan nilai korelasi r = -0.583; -0.631 dan -0: 514 pada musim
lembab. Untuk musim kering, hanya frekuensi 382.5 MHz menunjukkan korelasi yang
positif dan signifikan dengan r = 0.555, manakala korelasi kecil dan sederhana
untuk yang lain. Penemuan ini berguna kepada astronomi radio untuk menentukan
tempoh terbaik dalam kajian astronomi radio dengan gangguan yang paling rendah
dengan cara mempertimbangkan faktor cuaca di pantai timur Semenanjung Malaysia.
Di samping itu, penemuan ini akan memberi manfaat kepada pengguna spektrum
seperti telekomunikasi mudah alih, internet tanpa wayar, transmisi TV radio
dan penyiaran satelit.
Kata kunci: Kekuatan
isyarat radio; kelajuan angin; korelasi; pengurangan isyarat radio
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*Corresponding author; email: norhazmin@umt.edu.my
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