Pengaruh common channel interference terhaadp system throuhput pada jaringan wi-fi (standar IEEE 802.11G)

ANIF, Muhammad, Ir. Wahyu Dewanto, M.T

2010 | Tesis | S2 Teknik Elektro

Penggunaan perangkat telekomunikasi nirkabel telah sedemikian meluas, terutama sejak dibebaskannya izin pemakaian bidang frekuensi 2,4 GHz di Indonesia pada tahun 2005. Di sisi lain, kurangnya pengetahuan pengguna tentang frekuensi menyebabkan sering terjadi interferensi akibat pemakaian kanal frekuensi sama, yang disebut Common Channel Interference (CCI). Terjadinya CCI diduga menyebabkan menurunnya system throughput. Penelitian ini mengamati pengaruh CCI terhadap system throughput pada jaringan Wi-Fi (Standar IEEE 802.11g). Dilakukan analisis pengaruh enam parameter terhadap system throughput, yaitu jumlah station (Nst), daya pancar AP (Txap), jarak station terhadap AP (Dst-ap), jarak antar AP (Dap-ap), jumlah AP (Nap) dan selisih kanal frekuensi antar AP ((simbol)Chap). Diteliti juga dampak implementasi capacity based design terhadap system throughput dan diusulkan model matematis untuk menghitung system throughput pada jaringan Wi-Fi. Hasil penelitian menunjukkan bahwa pada kondisi terjadi CCI, system throughput menurun signifikan yaitu bernilai maksimum 50% dibandingkan dengan maximum throughput suatu AP. Dari percobaan yang dilakukan pada kondisi terjadi CCI, koneksi jaringan sering terputus sehingga menurunkan unjuk-kerja sistem. Penerapan capacity based design pada jaringan nirkabel dapat meningkatkan system throughput antara 2 hingga 3 kali lipat dibandingkan system throughput pada kondisi CCI. Model matematis yang diusulkan telah diuji di lokasi berbeda dan cukup valid dalam menghitung system throughput di suatu lokasi.

The use of wireless telecommunication devices have been extended, especially since the government released the permit on the 2.4 GHz frequency band in 2005. On the other side, lack of user knowledge about the 2.4 GHz frequency band often causes interference in many places as the effect of same frequency channel usage in nearby location, which is called common-channel interference (CCI). The occurrences of CCI presumably cause the degradation of system throughput. This research observed the influence of CCI on system throughput at Wi-Fi network (IEEE 802.11g Standard). The influence of six parameters on system throughput was analyzed, i.e. the number of station (Nst), the AP transmit power (Txap), the distance of station to the AP (Dst-ap), the distance between the AP (Dap-ap), the number of APs (Nap) and the difference of frequency channel between the AP ((symbol)Chap). Further, this research examined the implementation impact of capacity based design on the system throughput and mathematics model is proposed to calculate system throughput on Wi-Fi network. Results showed that when the CCI condition occurs, the system throughput is decreasing more significantly, i.e. maximum 50% compared with a maximum throughput of an AP. From the experiments conducted on the condition where CCI occurred, the network connection was often disconnected thus reducing the system performance. The implementation of capacity-based design on wireless networks can increase the value of system throughput 2 to 3 times better than when the CCI condition occurs. Mathematical model being proposed has been tested in different locations and is valid enough to calculate system throughput.

Kata Kunci : Wi-Fi, Common Channel Interference, Capacity Based Design, Throughput Model