User's Manual
Table Of Contents
- Copyright
- Attention
- Trademark
- Versions
- Applicable Model List
- Foreword
- Product Overview
- Structure
- Hardware Introduction
- Hardware Interface
- Electrical and Environmental Characteristic
- RF Interface
L811-EA Module Hardware User Manual Page
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7 RF Interface
7.1 RF PCB Design
7.1.1 Wire Routing Principle
The L811-EA module supports double RF antennas, the MAIN_ANT is for transmitting and receiving, and
the DIV_ANT is for receiving. Diversity antenna can improve the receiver sensitivity as well as the
downlink speed.
The RF connectors or solder joints must be connected to the L811-EA module by the trace lines. It is
recommended to use the microstrip line for RF line. It should be as short as possible with the insertion
loss controlled below 0.2dB, and has the impedance of 50 Ohm.
For antenna fine tuning, it is recommended to reserve a π circuit (the parallel inductors should connect to
the main ground) between L811-EA module and the antenna connector (or the solder joint).
Figure 7- 1 L811-EA π-type Circuit
L811-EA