Codan Radio Communications CASC165A 사용자 설명서
•
(
)
v
RF Maximum
Permissible
Exposure (MPE)
Exhibit Requirements for Installations in Canada
No antenna is supplied with this unit. Some suggested antennas are:
-
Manufacturer: Sinclair
Model: SC225
Gain: 0 dBd (2.15 dBi)
-
Manufacturer: Sinclair
Model: SC233
Gain: 3 dBd (5.15 dBi)
-
Manufacturer: Sinclair
Model: SD114
Gain: 7.5 dBd (9.65 dBi)
For Canada installations, you must ensure that your installation complies with the Maximum Permissible Exposure (MPE) requirements for general population
that are specified under RSS-102 Section 4 Table 4.
MPE and Safe Distance Calculations for Canada Installations
For Canada installations, the maximum power density resulting from the composite Effective Isotopic Radiated Power (EIRP) from the antenna connected to this
equipment must be limited to the maximum permissible exposure as stated below:
•
Power density limit for the band 152 to 174MHz = 1.291 W/m²
The MPE calculation for US is expressed as follows:
Power Density Pd (W/m²) =
��������
��∗��∗��
��
Where
•
d = distance from the antenna expressed in meters (m).
(
[���� ������ (������)+������ �������� (������)−���������� �������� (����)]
)
•
EIRP expressed in Watts (W) =
10
10
•
Tx Power (dBW) = 10*log[Tx Power (W)]
As an example, with the transmitter running at 125 watts output into an antenna with a gain of 10 dBi using a short cable with 0dB loss, to verify if 7.5meters is
a safe distance from the antenna to ensure exposure compliance of 1.21W/m
2
:
4) 125 Watts Tx Power = 20.97dBW
(
[���� ������ (20������)+������ �������� (10������)−���������� �������� (0����)]
)
(
30
)
5)
EIRP (W) =
10
10
= 10
10
= 1,000W
6)
Pd (W/m2) =
(
EIRP
)
=
(
1,000
)
=
(
1,000
)
=1.11 W/m
2
4∗π∗d
2
4∗��∗8.5
2
907.9
•
8.5 meters is a safe distance for Canada installations when using a 10dBi gain antenna.
When installing the antenna, the above relationship should be used to ensure the combination of power, antenna gain, and distance is such that the maximum
permissible power density is not exceeded. Different combinations of output power and antenna gain will result in different minimum safe distances.
The minimum safe distance, from a radiating structure using different Gain Antennas”
•
For the Band 152 to 174MHz with 2dBi Gain Antenna: d (safe distance) = 3.5 m
•
For the Band 152 to 174MHz with 6dBi Gain Antenna: d (safe distance) = 5.5 m
•
For the Band 152 to 174MHz with 10dBi Gain Antenna: d (safe distance) = 8.5 m