Malaysian Journal of Analytical Sciences Vol 19 No 5 (2015): 1065 - 1071

 

 

 

RADIO FREQUENCY INTERFERENCE: THE EFFECT OF AMBIENT CARBON DIOXIDE (CO₂) CONCENTRATION ON RADIO SIGNAL FOR RADIO ASTRONOMY PURPOSES

 

(Interferens Frekuensi Radio: Kesan Kepekatan Karbon Dioksida (CO₂) Ambien ke atas Isyarat Radio Dalam Kajian Astronomi Radio)

 

Nor Hazmin Sabri¹*, Sharifah Nurul Aisyah Syed Zafar², Roslan Umar^3,4, Wan Zul Adli Wan Mokhtar⁵

 

¹School of Fundamental Science

²Physic, Electronic and Instrumentation Programme, School of Ocean Engineering

Universiti Malaysia Terengganu, 21030 Kuala Terengganu, Terengganu, Malaysia

³East Coast Environmental Research Institute (ESERI)

⁴Faculty of Islamic Contemporary Studies

Universiti Sultan Zainal Abidin, Gong Badak Campus, 21300 Kuala Terengganu, Terengganu, Malaysia
⁵Department of Physics, Faculty of Science and Mathematics,

Universiti Pendidikan Sultan Idris, 35900 Tanjung Malim, Perak, Malaysia

*Corresponding author: norhazmin@umt.edu.my

 

 

Received: 14 April 2015; Accepted: 9 July 2015

 

 

Abstract

Radio astronomy is a complementary to optical astronomy. Radio astronomy observation is conducted using large radio antennas referred to as radio telescopes, that are either used singularly, or with multiple linked telescopes utilizing the techniques of radio interferometry and aperture synthesis. In this study, weather factor that affected the Radio Frequency Interference (RFI) is investigated. An ambient carbon dioxide (CO₂) concentration in the environment is determined to study the effect on radio signal up to 8GHz for radio astronomy purposes. The RFI pattern change against CO₂ concentration is determined for one-hour observation time. The observations were conducted at KUSZA Observatory, East Coast Environmental Research Institute (ESERI) and UniSZA situated in Merang, Terengganu using spectrum analyser for RFI measurement and gas meter for CO₂ concentration. The study findings found that for up to 600 ppm of CO₂ concentration, there are no significant effect detected on radio signals. Thus, the radio astronomy observations may not affected. This study is very important for researchers in the radio astronomy field for determining the best location for radio telescope sitting for future research in radio astronomy.

 

Keywords: ambient carbon dioxide, radio signal, radio astronomy, radio frequency interference

 

Abstrak

Astronomi radio adalah pelengkap kepada astronomi optik. Cerapan astronomi radio dijalankan dengan menggunakan teleskop radio dengan piring yang besar yang dipanggil teleskop radio, yang mana ianya boleh digunakan secara sendirian atau secara gabungan beberapa teleskop radio dengan menggunakan teknik interferometry dan sintesis bukaan. Dalam kajian ini, faktor cuaca yang memberi kesan terhadap interferens frekuensi radio (RFI) diselidik. Kepekatan karbon dioksida (CO₂) ambien dalam persekitaran ditentukan bagi mengkaji kesannya terhadap isyarat radio dalam julat sehingga 9GHz untuk tujuan kajian astronomi radio. Perubahan pola RFI terhadap perubahan kepekatan CO₂ dikenalpasti bagi tempoh satu jam cerapan dibuat. Cerapan dibuat Balai Cerap KUSZA, Institut Penyelidikan Alam Sekitar Pantai Timur (ESERI) dan UniSZA yang terletak di Merang, Terengganu dengan menggunakan penganalisa spectrum untuk pengukuran RFI dan pengukur gas untuk kepekatan gas CO₂. Hasil kajian mendapati, bagi kepekatan CO₂ ambien sehingga 600 ppm, tiada kesan yang ketara dilihat terhadap isyarat radio. Oleh itu, cerapan astronomi radio tidak akan terganggu. Kajian ini sangat penting untuk pengkaji dari bidang astronomi radio bagi penentuan lokasi yang paling sesuai untuk meletakkan teleskop radio untuk kegunaan kajian akan dating dalam bidang astronomi radio.

 

Kata kunci: karbon dioksida, isyarat radio, astronomi radio, interferens frekuensi radio

 

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