MeiG_SLM320_Hardware Design Manual
MeiG Smart Technology Co., Ltd
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5 Antenna interface
SLM320 module design interface, there are three antennas, the antenna impedance 50
Ω
.
Table 19 Definition of pin of antenna interface
Pin Name
Pin Number
Description
I/O
Remark
ANT_MAIN
49
main antenna port
IO
50Ω
impedance
BT_ANT
35
WIFI/BT antenna port IO
50Ω
impedance
ANT_GNSS
47
GPS
antenna port
IO
50Ω
impedance
5.1 Introduction to Antenna Interface
SLM320 provides three antenna pins: ANT_MAIN and ANT_WIFI/BT to improve the product's TDD-LTE/
FDD-LTE, WIFI/BT transceister performance. It is recommended to use with the module, RF connector
match 50 Ω impedance of the antenna.
Note:
In order to ensure the communication capability of all frequency bands, please connect all antennas.It is
recommended that applications carefully select RF wiring. RF wiring needs to be selected with minimal
loss. RF wiring for RF loss requirements is recommended as follows:
GSM900 <0.6dB
DCS1800 <1.0dB
TDD-LTE<1.2dB
FDD-LTE<1.2dB
WIFI/BT<1.2dB
GNSS<1.0dB
5.2 Radio frequency reference circuit
The reference circuit for antenna connection of ANT_MAIN, ANT_WIFI/BT is shown in the figure below.
In order to obtain better RF performance, the following four points should be paid attention to when
designing schematic diagram and PCB layout:
1. Schematic design, near the module RF port reserved type matching circuit, capacitor default not
attached;
2. Schematic design, redundant RF connectors between the RF port of the module and the antenna,
used for certification test, RF connectors are not attached after mass production and delivery;
(Reference: RF Connector -1P-H176);
3. Schematic design, type matching circuit is reserved near the antenna end, capacitor is not affixed
