HUAWEI ME909s Series LTE Mini PCIe Module
Hardware Guide
RF Specifications
Issue 02 (2016-09-07)
Huawei Proprietary and Confidential
Copyright © Huawei Technologies Co., Ltd.
39
Polarization
The polarization of an antenna is the orientation of the electric field vector that rotates
with time in the direction of maximum radiation.
The linear polarization is recommended for the antenna of ME909s Mini PCIe module.
Radiation Pattern
The radiation pattern of an antenna reflects the radiation features of the antenna in the
remote field region. The radiation pattern of an antenna commonly describes the
power or field strength of the radiated electromagnetic waves in various directions
from the antenna. The power or field strength varies with the angular coordina
tes (θ
and φ), but is independent of the radial coordinates.
The radiation pattern of half wave dipole antennas is omnidirectional in the horizontal
plane, and the incident waves of base stations are often in the horizontal plane. For
this reason, the receiving performance is optimal.
The following radiation patterns are recommended for the antenna of ME909s Mini
PCIe module.
Primary/Diversity antenna: omnidirectional
In addition, the diversity antenna's pattern should be complementary with the
primary's.
Gain and Directivity
The radiation pattern of an antenna represents the field strength of the radiated
electromagnetic waves in all directions, but not the power density that the antenna
radiates in the specific direction. The directivity of an antenna, however, measures the
power density that the antenna radiates.
Gain, as another important parameter of antennas, correlates closely to the directivity.
The gain of an antenna takes both the directivity and the efficiency of the antenna into
account. The appropriate antenna gain prolongs the service life of relevant batteries.
The following antenna gain is recommended for ME909s Mini PCIe module:
Gain of the primary antenna ≤ 2.5 dBi
Gain of the diversity antenna ≤ 2.5 dBi
ECC of the Antenna
ECC is short for Envelope Correlation Coefficient. It is the cross-correlation value of
the complex patterns of the master and diversity antenna. It indicates how similar the
magnitude and the phase patterns of the two antennas are. If two antennas have no
similarity, the ECC should be zero. Actually, the less ECC, the better diversity
performance.
The following ECC is recommended for ME909s Mini PCIe module.
ECC
≤
0.5 (working frequency below 0.96 GHz)
ECC
≤
0.3 (working frequency above 1.4 GHz)