HW V4 / © 2005 – 2013 Aaronia AG, DE-54597 Strickscheid
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Manual Spectran V4
Tables and exposure limits
12. Tables and exposure limits
12.1. Convesion tables
Table 1: Conversion dBm to W/m² with HyperLOG-antenna
Assuming the use of an „idealized“ measurement setup, like our HyperLOG antenna with
5dBi gain and one of our 1m RG316U cables with 1dB damping, the following conversion
table can be applied to the signal sources below (figures in W/m²)
dBm
GSM900
UMTS
Lambda X
WLan
GSM1800
+10
0,45
2,2
1,34
3,3
1,8
+9
0,36
1,8
1,06
2,7
1,4
+8
0,28
1,4
0,84
2,1
1,1
+7
0,23
1,1
0,67
1,7
0,90
+6
0,18
0,89
0,53
1,3
0,72
+5
0,14
0,70
0,42
1,06
0,57
+4
0,11
0,56
0,34
0,84
0,45
+3
0,09
0,44
0,27
0,67
0,36
+2
0,07
0,35
0,21
0,53
0,29
+1
0,06
0,28
0,17
0,42
0,23
0
0,045
0,022
0,13
0,033
0,018
-10
0,004 5
0,002 2
0,013
0,003 3
0,001 8
-20
0,000 45
0,000 22
0,001 3
0,000 33
0,000 18
-30
0,000 045
0,000 022
0,000 13
0,000 033
0,000 018
-40
0,000 004 5
0,000 002 2
0,000 013
0,000 003 3
0,000 001 8
-50
0,000 000 45
0,000 000 22
0,000 001 3
0,000 000 33
0,000 000 18
-60
0,000 000 045 0,000 000 022 0,000 000 13
0,000 000 033
0,000 000 018
We assumed the following center frequencies (f) here:
GSM900 (f = 900MHz),
Lambda X (f = 1550MHz),
GSM1800/DECT (f = 1800MHz),
UMTS (f = 2000MHz)
WLan / microwave ovens (f = 2450MHz).
The conversion table demonstrates that per 10dB step, power density decreases by a factor
of 10. This applies in a similar manner to the 1dB steps, which also change in a constant
manner. Consequently, this table permits easy and fast conversion of indicated dBm values
(for example, from the optional PWK detector) into PEAK field strength or, respectively,
power density in W/m². This table can just as well be used with different antennas,
attenuators or cables:
For example, should you be using our 20dB attenuator (option), you would extract those
rows from the table whose dBm values are 20dB higher, for example, -10dBm instead of
-30dBm. As a different example, should you be using an antenna with 24dBi gain, you would
use those values 19dB lower than the actual reading ((24dBi minus 5dBi [as 5dBi gain is
already included in the calculated table values]). For example: -43dBm instead of -24dBm.
