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3.8.2 RF Matching Guide
IMS2
module
Primary
Antenna
Pin15 RF_1
Antenna
matching
RF connector
1. Reserve the matching circuit as
depicted in the topological structure
below.
2. The matching circuit should be as close
to the module as possible.
The impedance (S11) should be close to
50 Ω, VSWR < 1.5.
Figure 3-6. RF matching guide
3.8.3 Interference and Sensitivity
This section includes tips to help developers identify interferences that may affect
the IMS2 module when used in systems.
 Interference from other wireless devices
– Harmonics, inter-modulated signals generated from wireless devices
within the RX ranges of the modules may result in degraded RX
performance.
– We highly recommend checking the RX performance of entire
systems within the shielding environment.
 Interference from the host interface
– High-speed signal-switching elements in systems can easily couple
noise into the module (ex.: DDR memory, LCD modules, DC-DC
converters, PCM signals).
 Methods to avoid sources of interference
– Antenna location is important; we recommend directing the
antenna away from high-speed switching signals. Furthermore, the
trace from the module to the antenna should be as short as possible
and must be shielded by complete grounding.
– The IMS2 module is well shielded; high-speed elements (Ex.: DDR
memory, LCD modules, DC-to-DC converters, PCM signals) on a
system should have shielding reserved during the early stages of
development.