Interference; Antenna Requirements - Huawei ME909u-521 Hardware Manual

HUAWEI ME909u-521 LTE LGA Module
Hardware Guide
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 ME909u-521.



4.5.2 Interference

Besides the antenna performance, the interference on the user board also affects the
radio performance (especially the TIS) of the module. To guarantee high performance
of the module, the interference sources on the user board must be properly controlled.
On the user board, there are various interference sources, such as the LCD, CPU,
audio circuits, and power supply. All the interference sources emit interference signals
that affect the normal operation of the module. For example, the module sensitivity
can be decreased due to interference signals. Therefore, during the design, you need
to consider how to reduce the effects of interference sources on the module. You can
take the following measures: Use an LCD with optimized performance; shield the LCD
interference signals; shield the signal cable of the board; or design filter circuits.
Huawei is able to make technical suggestions on radio performance improvement of
the module.

4.5.3 Antenna Requirements

The antenna for ME909u-521 module must fulfill the following requirements:
Antenna Requirements
Frequency range
Bandwidth of primary
antenna
Issue 05 (2017-12-15)
ECC ≤ 0.5 (working frequency below 0.96 GHz)
ECC ≤ 0.3 (working frequency above 1.4 GHz)
 The antenna consists of the antenna body and the relevant RF transmission cable. Take the
RF transmission cable into account when measuring any of the preceding antenna
indicators.
 Huawei cooperates with various famous antenna suppliers who are able to make
suggestions on antenna design, for example, Amphenol, Skycross, etc.
Huawei Proprietary and Confidential
Copyright © Huawei Technologies Co., Ltd.
Depending on frequency band(s) provided by the network
operator, the customer must use the most suitable
antenna for that/those band(s)
70 MHz in GSM 850
80 MHz in GSM 900
170 MHz in GSM 1800
140 MHz in GSM 1900
250 MHz in WCDMA /LTE Band 1
140 MHz in WCDMA/LTE Band 2
70 MHz in WCDMA/LTE Band 5
80 MHz in WCDMA/LTE Band 8
170 MHz in LTE Band 3
190 MHz in LTE Band 7
71 MHz in LTE Band 20
RF Specifications
54