RFID-UHF-Antennas
8
4 Technical Data
Typ Nr�
ANT820
Frequency range
MHz
865-870
Antenna gain
dBic
4
Polarisation
Right-hand circular (RHC)
VSWR
< 1,3 : 1
Impedance
Ω
50
Front-to-back ratio
cm
> 10
Max� radiated power
(ETSI EN 302 208)
W ERP
0,5
Far-field divergence
°
100
Connection
TNC socket
Protection class
IP 67
Weight
g
320
Dimensions (W x H x D)
mm
156 x 126 x 36
Material
Antenna cover: Polymer-Blend
Installation
Four through holes Ø 4�2 mm for M4 screws
Temperature range
Storage temperature: -40° C – +85° C
Ambient temperature: -20° C – +55°C
The antenna ANT820 is right-hand circular polarised and has a typical antenna
gain of 4 dBic� In the figure “Circular antenna gain against frequency for the
ANT820” the circular gain is plotted against frequency� The operating range of the
antenna is shown in grey� Outside the operating range the gain of the antenna
ANT820 drops off� Due to this drop off, interference from other systems is mini-
mised, as is interference to other systems� The figure “Directional characteristic of
the ANT820 (RHC)” shows the righthand circular directional characteristic of the
ANT820� The half power beam width is approx� 100° and the front-to-back ratio is
>10 dB� The axial ratio (AR) of the ANT820 is significantly less than 2 dB for the
major part of the upper hemisphere (θ = ± 90°). The matching against frequency is
below -18 dB in the working range of the antenna� The 10 dB bandwidth is greater
than 20 MHz� The figures relate to a reflection-free environment� For real environ-
ments with reflections, there may be variations from the values shown here (on
this topic see chapter 7 Installation / Attachment)�
