User Manual

6 APCD-LM048-1.1
1: Introduction
environment by selecting the alternate polarization when the other polarization signal fades
significantly. This effectively reduces the depth, frequency and duration of fades when
compared to a non-active or non-diversity antenna system.
Horizontal and vertical polarizations are relative to the earth. Since the EUM3006 can be
mounted in one of two orientations, we use the terms longitudinal axis and transverse axis to
refer to the axes of the modem. See Figure 2.
Figure 2 EUM3006 Longitudinal and Transverse Axes
The antenna patterns are longitudinal and transverse polarization. If the modem is mounted
vertically, then the longitudinal polarization coincides with vertical polarization and the
transverse is for horizontal polarization. If the modem in mounted horizontally, then the
longitudinal axis is for horizontal polarization and the transverse is for vertical polarization. See
the installation section for suggestions on mounting orientation.
The EUM3006 samples the signal strength from both antenna polarizations during the
preamble of every received packet and automatically selects the best signal. When the
EUM3006 transmits, it sends on the antenna polarization that was last used to receive a
signal.
The integrated antenna has a front-to-back ratio of more than 15 dB, which helps to suppress
interference.
1.3.3 Ethernet Port
The EUM3006 has a 10BaseT Ethernet RJ-45 connector at the end of 25 feet of CAT-5e
outdoor Ethernet cable. This makes installation much easy and robust, since this length is
Vertical
Horizontal
Modem Vertically Mounted
Modem Horizontally Mounted
Longitudinal Axis
Transverse
Axis
Longitudinal Axis
Transverse
Axis