BlueBox IDTRONIC UHF Advant 5238U-PN-C, Руководство пользователя

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BLUEBOX Advant Profinet Page 34 of 71
5 Antennas
The BLUEBOX is equipped with a connector for an external antenna that is
available in various models (items 902xU and 922xU).
The read range of an RFID system always depends on various factors like
antenna size, transponder size, transponder IC type, orientation between
transponder and device antenna, position of the transponder versus the device
antenna, noise environment, metallic environment, etc. Therefore all data about
read ranges can only be typical values measured under laboratory conditions. In
real live applications the read range may differ from the data mentioned in the
datasheet.
The maximum RF output power must be calculated considering the radiating
power limits defined in the region of usage.
In Europe region radiating power limits are described in relation to dipole
antenna and ERP (Efficient Radiating Power) is used as a measure. The
maximum RF output power is defined by the antenna gain, the half power beam
width and the cable attenuation on the device - antenna connection. For
antennas with a half power beam width of up to 70° a power of P
ERP,max
= 2W
ERP is allowed. For other half power beam widths a reduced power of
PERP,max
=
0.5W ERP. The maximum RF output power is defined as:
P
C,max
= P
ERP,max
- G
IC
+ 5.15 + C
L
Where:
P
C,max
Maximum RF output power in dBm
P
ERP,max
Maximum ERP power of the antenna in dBm
G
IC
Circular antenna gain in dBic
C
L
Cable loss in dB
In North America region radiating power limits are described in relation to
isotropic antenna and EIRP (Efficient Isotropic Radiating Power) is used as a
measure. The maximum RF output power is defined by the antenna gain, the
half power beam width and the cable attenuation on the reader - antenna
connection. A power of P
EIRP,max
= 4W EIRP is allowed. The maximum RF output
power is defined as:
P
C,max
= P
EIRP,max
- G
IC
- 2.15 + 5.15 + C
L
Where: