Antenna basics
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Transcript of Antenna basics
Vertical Separation
k
a
The following is valid for 900 Mhz., 1800, 1900Mhz and co-located 900+1800/1900 Mhz.
Requirements: Tx -Rx and Rx- Tx: 30 dB
Pre-condition: No influence from tower structures more than 2m
bet Ant and Tower. ( a in figure)
Vertical Separation: Tx - Rx and Rx - Tx
Minimum 0.2 m
( k in figure)
Requirements: Tx -Rx and Rx- Tx: 30 dB
Horizontal Separation: See Table Below
Gain dBi 900 Mhz 1800/1900 900+1800/1900
<10 3m 1.5m 1m
>10 5m 2.5 m 1m
Table: Horizontal Separation
Horizontal Separation
d
d
k
The following is valid for 900 Mhz., 1800/1900Mhz and co-located 900 + 1800Mhz.
Requirements: Rx -Tx and Tx - Rx: 30 dB
Combined Separation:
Vertical (k) : minimum 0.5m
Horizontal (d) : no limitation
Horizontal Separation
a
H
a = Separation between Rx antenna
H = Height of mast plus building
Horizontal Separation
Table: Horizontal Separation
900 MHz 1800/1900
Minimum: 4m 2m
Required: 6m 3m
a
Maximum Diversity
Minimum Diversity
Table 3 900 Mhz: Height of antenna above roof
Distance (D) to obstacle edge Height (H) above roof
0-1 m 0.5m
1-10m 2m
10-30m 3m
>30m 3.5m
if possible, use 2m as the minimum height if there is a risk that people can walk close to the antenna.
D
H
Horizontal Separation
Table 3 1800/1900 Mhz: Height of antenna above roof
Distance (D) to obstacle edge Height (H) above roof
0-2 m 0.5m
2-10m 1m
>10m 2m
if possible, use 2m as the minimum height if there is a risk that people can walk close to the antenna.
D
H
Horizontal Separation
Vertical Separation
k
The following is valid for 900 Mhz., 1800, 1900Mhz and co-located 900+1800/1900 Mhz.
Requirements: Tx -Rx and Rx- Tx: 30 dB
Pre-condition: No influence from tower structures in the forward direction of antenna.
Vertical Separation: Tx - Rx and Rx - Tx
Minimum 0.2 m
( k in figure)
k
Horizontal SeparationRequirements: Tx-Rx and Rx-Tx: 30dB
Vertical Separation: See Table Below
65+/-10 0.4m 0.3m 0.3m
90+/-10 1m 0.5 m 0.5 m
105+/-10 1.5m 0.7m 0.7m
120+/-10 2m 1m 1m
180+/-10 5m 2.5m 2.5m
Hor. B.W. 900 Mhz 1800/1900 900+1800/1900
Min 20 mm Min 20 mmForward Direction
90º
Max 30º
Horizontal Separation
Combined vertical /horizontal
the following is valid for 900 Mhz, 1800 /1900 Mhz and
co-located 900 + 1800/1900 Mhz
Requirements: Tx -Rx and Rx- Tx: 30 dB
Vertical Separation: vertical directionmin 0.5
horizontal direction no limit
k
d
H
a
Max
imu
m d
iver
sity
axi
s
Rxa Rxb
Diversity Separation and Antenna Ht.
The relationship between the desirable diversity separation and the antenna ht. Is given by:
900 Mhz: a >= H/10 1800/1900 a.>=H/20
a = distance between Rx ant.
H = height of mast + building
Horizontal Separation for Space DiverstiyThe horizontal separation between the antennas shall be as stated in thetable below:
Horizontal separation for space diversity
900 Mhz 1800/1900 Mhz
Minimum 4m 2m
Recommended 6m 3m
Horizontal Separation
Table 3 900 Mhz: Height of antenna above roof
Distance (D) to obstacle edge Height (H) above roof
0-1 m 0.5m
1-10m 2m
10-30m 3m
>30m 3.5m
if possible, use 2m as the minimum height if there is a risk that people can walk close to the antenna.
D
h
Horizontal Separation Table 3 1800/1900 Mhz: Height of antenna above roof
Distance (D) to obstacle edge Height (H) above roof
0-2 m 0.5m
2-10m 1m
>10m 2m
if possible, use 2m as the minimum height if there is a risk that people can walk close to the antenna.
D
h
WALL
Top View
WALL
Top View
WALL
Top ViewForward Direction
Forward Direction
15º Minimum
Forward Direction
More than 15º
W
H
D
A = 1.02455 m2
Data Value
Height (H) 1467 mm
Width (W) 1550 mm
Depth (D) 661mm
Vertical Separation
k
a
Receive
Transmit
The following is valid for 900 Mhz., 1800,1900Mhz and co-located 900 + 1800/1900 Mhz.
Requirements: Tx -Rx and Rx- Tx: 30 dB
Pre-condition: No influence from tower structures more than 2m
bet. Ant and Tower. ( a in figure)
Vertical Separation: Tx - Rx and Rx - Tx
Minimum 0.2 m
( k in figure)
