BlueBox IDTRONIC GEN2 ADVANT UHF, Руководство пользователя

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BLUEBOX Advant UHF Page 58 of 102
5 Antennas
The BLUEBOX is available with internal antenna directly integrated on the
device cover (items 5221U, 5222U, 5223U, 5221U-S, 5222U-S, 5223U-S and
5222U-MB-S). Alternatively the
BLUEBOX (items 5237U, 5238U, 5239U,
5237U-S, 5238U-S, 5239U-S and 5238U-MB-S) is equipped with a connector for
an external antenna that is available in various models (items 902xU and 922xU)
or four connectors for up to four external antennas (items 5231U, 5232U, 5233U
and 5232U-MB).
The read range of an RFID system always depends on various factors like
antenna size, transponder size, transponder IC type, orientation between
transponder and reader antenna, position of the transponder versus the reader
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.
In case of BLUEBOX with external antennas 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 reader - 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