Sierra Wireless AirPrime EM7700, Hardware Integration Manual

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RF Integration
Rev 2 Apr.12 Proprietary and Confidential 15
• The Tx power and corresponding broadband noise of other wireless devices
may overload or increase the noise floor of the module’s receiver, resulting in
Rx desense.
The severity of this interference depends on the closeness of the other antennas
to the module’s antenna. To determine suitable locations for each wireless
device’s antenna, thoroughly evaluate your host device’s design.
Host-generated RF interference
All electronic computing devices generate RF interference that can negatively
affect the receive sensitivity of the module.
Proximity of host electronics to the antenna in wireless devices can contribute to
decreased Rx performance. Components that are most likely to cause this
include:
• Microprocessor and memory
• Display panel and display drivers
• Switching-mode power supplies
Device-generated RF interference
The module can cause interference with other devices. Wireless devices such as
AirPrime embedded modules transmit in bursts (pulse transients) for set durations
(RF burst frequencies). Hearing aids and speakers convert these burst
frequencies into audible frequencies, resulting in audible noise.