OBID
i-
scan
®
HF
Installation
ID ISC.LRM2500-A
FEIG ELECTRONIC GmbH
Page 9 of 30
M10210-4e-ID-B.docx
3.3 Antenna connection
The SMA socket „ANT1“ is located on the lower circuit board for connecting the antenna to the ID
ISC.LRM2500.
Active external function units (e.g. ID ISC.DAT) can also be supplied with 8 V
through the
antenna terminal. The maximum current draw is then not allowed to exceed 150mA. This additional
power consumption must be considered for the total reader power consumption.
The maximum tightening torque for the SMA socket is 0.45 Nm (4.0 lbf in).
Attention:
Exceeding the tightening torque will destroy the socket.
Terminal
Description
ANT1
For connecting the antenna
Table 2: Antenna jack
The standing wave ratio VSWR for the antenna should not exceed a value of 1,3.
For reaching optimal read ranges the coaxial cables between readers and antenna must
have defined lengths. For all antennas of the company FEIG ELECTRONICS GmbH and
for all antennas which with the tuning boards (e.g. ID ISC.DAT, ID ISC.MAT b and ID
ISC.MAT s) of FEIG ELECTRONICS GmbH is made the optimal length of the coaxial ca-
ble is 1.35 m (Article No. 1654.004.00.00, Name ID ISC.ANT.C-B). See also Mounting
Manual Power Splitter ID ISC.ANT.PS-B and ID ISC.ANT.MUX.
The optimum operating Q factor of the antenna should be in a range of Q
oper
= 10...30. To
determine the operating Q the antenna must be supplied with a 50 Ohm source such as
a network analyzer or frequency generator.
To prevent external coupled noise, the antenna cable must be fitted with the included
EMC ferrite ring core
28 mm x 20 mm.
The antenna line must be wound around the
ring core for at least 4 turns. The distance between the Reader termination and the ring
core should be maximum 10 cm (see
).
When connecting an antenna, ensure that it does not exceed the permissible limits pre-
scribed by the national regulations for radio frequency devices.
Figure 3: Antenna line with EMC ring cores
