teknik transmisi seluler dtg3g3 · tri nopiani damayanti,st.,mt dadan nur ramadan,s.pd,mt yuyun...
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Tri Nopiani Damayanti,ST.,MT
Dadan Nur Ramadan,S.Pd,MT
Yuyun Siti Rohmah, ST.,MT
Suci Aulia,ST.,MT
ANTENA PADA SISTEM SELULER
Teknik Transmisi Seluler
(DTG3G3)
Macam-Macam Jenis Antena yang ada di BTS
1) Omnidirectional
Tx
Rx
Rx
Pada kondisi awal biasanya digunakan pola omnidirectional (tergantung demand) di gunakan pada lingkup
yang mempunyai base station terbatas dan cenderung untuk posisi pelanggan yang melebar
Antena yang memiliki pola pancaran sinyal ke segala arah dengan daya sama
Menghasilkan cakupan area yang luas, gain dari antena omnidirectional harus memfokuskan dayanya
secara horizontal (mendatar,dengan mengabaikan pola pemancaran ke atas dan ke bawah,sehingga antena
dapat di letakan di tengah-tengah base station
Keuntungannya jenis ini adalah dapat melayani jumlah pengguna yang lebih banyak
kesulitannya adalah pada pengalokasian frequensi untuk setiap sel agar tidak terjadi interferensi
Macam-Macam Jenis Antena yang ada di BTS
2) Sectoring 120o
3) Sectoring 60o Kegunaan dari pola Sectoring
a. Menambah kapasitas
b. Mengurangi interferensi
• Keuntungan antenna sektoral mempunyai gain
yang lebih besar daripada antenna
omnidirectional. Biasanya antenna sektoral
mempunyai gain antara 10-19 dBi
RBS / BTS
= Radio Base Station / Base Transceiver Station = Merupakan perangkat transceiver yang berhubungan dari /
ke pelanggan (Interface / repeater antara MS dan MSC) . = Elemen-elemen RBS :
Transceiver Control Unit / BSC / Base Station Controller Antena
Data terminal
single
antenna
base station
housingjalur transmisi
gelombang
mikro menuju
BSC
site 3 sektor dengan 7
array antena tiap
sektornya
Bagaimana bentuk antena pada lokasi site ?
Basic Antennas System
l/2 G=2.14 dBi Z= 73 W
a. Dipole
l/4
G=4 dBi Z= 36 W
b. monopole
Ground plane
c. Loop Ground plane
conductor Feed point
d. Microstrip/ patch
dielectric
l/2
l/2
l
Base Station Antenna (1)
• Use antenna with higher gain • Could be omnidirectional or sectoral depending on cell type • Collinear antenna:
S
2l
2l
4l
feeder
line
Omnidirectional
Radiation
Pattern
boresight
main lobe
side lobe (elevation)
Base Station Antenna (2)
• Log periodic dipole array (LPDA)
Dipoles Transmission
line
- BW is smaller than LPDA
- typical gain 12 – 14 dB
Reflector Driven element (dipole)
Directors
• Yagi antenna
Directional Radiation
Pattern
main lobe
main lobe side lobe back lobe
- very wide BW, with constant SWR
- typical gain 10 dBi
Sector Antennas Reflectors And Vertical Arrays
Typical commercial sector antennas
are vertical combinations of dipoles,
yagis, or log-periodic elements with
reflector (panel or grid) backing:
Vertical plane pattern is determined by number of
vertically-separated elements
varies from 1 to 8, affecting mainly gain and
vertical plane beamwidth
Horizontal plane pattern is determined by:
number of horizontally-spaced elements
shape of reflectors (is reflector folded?)
Sector Antennas Reflectors And Vertical Arrays
Typical commercial sector antennas
are vertical combinations of dipoles,
yagis, or log-periodic elements with
reflector (panel or grid) backing:
Vertical plane pattern is determined by number of
vertically-separated elements
varies from 1 to 8, affecting mainly gain and vertical
plane beamwidth
Horizontal plane pattern is determined by: number of horizontally-spaced elements
shape of reflectors (is reflector folded?)
This is inside the GSM Dual band
antenna.
left side is for 900MHz band.
Right side array is for 1800MHz.
Is a Patch Panel antenna.
TILTING ANTENA
Tilting antena adalah suatu pengaturan kemiringan antena yang berfungsi untuk
menetapkan area yang akan menerima cakupan sinyal
1. TILTING MEKANIK
Tilting mekanik adalah mengubah
kemiringan antena dengan cara
mengubahnya dari sisi fisik antenna.
Rigger memiliki alat ukur tilt meter yang
memperlihatkan derajat kemiringan antena.
2. TILTING ELEKTRIK
Tilting elektrik adalah mengubah coverage antenna dengan cara mengubah fasa antenna,
sehingga terjadi perubahan pada beamwidth antenna. Mengubah fasa antenna dapat
dilakukan dengan cara mengubah setingan elctrical tilt pada antenna, yaitu 1,2,3 dst.
Pengaturan tilt elektrik biasanya berada di bagian bawah antena.
This is the electrical tilt image. The cable distance between the input feed and
the antenna element is varied by a slider. This rotation can be controlled
remotely also by using a motor.
ATP BTS 2G
Telkomsel C Project
Site ID : JKU540
Site Name : MAHONIUJUNGMD
Site Location : Jl. Mahoni selatan Gg A RT.14/10
Jakut
BTS Type : BTS3900A Outdoor
Performance Criteria of Antenna (1)
• Antenna pattern, defined at azimuth and elevation orientation either omni or bidirectional antenna
• Main lobe & side lobe, the lower side lobe the better resistance to interference
• Input impedance, usually complex matching input impedance and feeder line impedance is very critical to have maximum power transfer from feeder to antenna
• Beamwidth, usually defined as angular separation where there is 3 dB reduction from bore-sight
• Directivity & Gain, is ratio of radiation intensity at wanted direction and coverage radiation intensity over all direction
• Bandwidth, define operating range of antenna, limited by SWR. A typical BW is for SWR 1:1.2 at the band edge.
• Polarization, defined by orientation of
Performance Criteria of Antenna (2)
• Front to Back Ratio (FBR), is ratio between main lobe & back
lobe, very impotant for directional antenna.