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A8520E24A91 – User’s Manual
Release Date 02/27/12
The end user is responsible for ensuring compliance with harmonized frequencies and labeling
requirements for each country the end device is marketed and sold.
For more information see:
Radio And Telecommunications Terminal Equipment (R&TTE)
http://ec.europa.eu/enterprise/rtte/index_en.htm
European Conference of Postal and Telecommunications Administrations (CEPT)
http://www.cept.org/
European Telecommunications Standards Institute (ETSI) http://www.etsi.org/
European Radio Communications Office (ERO)
2.2.
Potential Interference Sources
The two main mechanisms that allow a PurePath wireless system to co-exist amicably in close
proximity to other 2.4 GHz radio systems are:
The adaptive frequency hopping scheme described in section 2.2 that ensures that RF
channels used by other radio systems are avoided
Adaptive listen-before-talk mechanism that measures energy in RF channel before
transmitting and avoids transmitting if the channel is already in use
These mechanisms together ensure that other radio systems are minimally impacted by a
PurePath Wireless audio network in normal circumstances. However, since a low-latency audio
network by its very nature transports a very time-critical data stream, both mechanisms have
adaptive thresholds to ensure that the audio network is given its fair share of RF spectrum in
very crowded RF environments.
2.3.
Approved Usage
The A8520E24A91 module has been approved for use in the US, Canada and Europe. The
user is encouraged to use minimum power required to establish a link, thus minimizing
interference.
Changes or modifications to the module and/or operation outside the limits are prohibited and
could void the user’s authority to operate the modules.
2.3.1. USA and Canada
Within the USA and Canada, the A8520E24A91 modules have been approved for use as
digitally modulated transmitters, for which they conform to the BW (a minimum of 500 kHz 6-dB
BW for US, a maximum BW of 0.5% of the carrier frequency for Canada), power spectral
density (max of 8 dBm / 3 kHz), total output power (max of 1W including the antenna gain) and
spurious radiation (harmonics and others including the restricted bands) requirements.
