Clear-Com HME DX410, Руководство пользователя

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Operation in Severe Environments
During normal operation, the fact that the system is constantly changing the channel list in use is transparent to the user. It
is possible, however, that in an environment with severe interference that the system may experience a slight degradation.
In the AHF mode, the Clear-Com system will use a minimum of 15 channels. If the environment is very crowded and
less than 15 channels are truly available, there could be increased radio ‘packet loss’ due to the high interference. The
following symptoms may be observed with AFH systems in a highly congested radio environment:
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This may result in system ‘busy’ indications. Channel lists are updated every few seconds, and in a severe
environment it is possible that these lists get missed by the communicator.
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Slight degradation in audio fidelity between the headsets and base station. This would be due to the same
symptom as the ‘busy’ indications. The HD audio processing is tolerant to this condition, which is why the
degradation may only be slight.
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Longer times to register. Registration may take longer, since the headset has to acquire the channel list from
the base station. If the base station has excluded a lot of channels, this takes longer as the communicator
does not have the exclusion list and looks for the base on channels it is not using.
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Initial sync time increase. For the same reason registration may take longer, the initial headset sync on power
up may take longer.
Required AFH Equipment
In order to utilize AFH, the base station must be set to European mode. The headsets and belt packs must also be AFH
capable. AFH capable headsets and belt packs will have the letters ‘AFH’ labeled on the belt pack and headsets. AFH
communicators will auto detect if the system is in AFH mode and adjust their operation accordingly.
Non-AFH Equipment
Headsets and belt packs that are not AFH capable must be operated with either a non-AFH base station or an AFH base
station selected to operate in All, High or Low band mode. Headsets and belt packs that are not AFH capable will not have
the letters ‘AFH’.
Interference Mitigation
Certain techniques can be used in an attempt to mitigate interference between different equipment in the 2.4 GHz
spectrum. Some of these are:
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Physical separation . If possible, equipment operating in the 2.4 GHz spectrum should be operating as far as
physically possible from the HME base station. A Wi-Fi access point or router is a common piece of equipment
that could interfere with the DX410 system, or vice versa. These two pieces of equipment in particular should
not be located close together.
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Spectral separation . Most Wi-Fi access points allow the administrator to set the channel and bandwidth that
system operates on. Some systems employ an ‘auto’ mode, in which the Wi-Fi access point will automatically
selected the channel. With Wi-Fi access points, it is sometimes advantageous to manually select a channel
number to keep the Wi-Fi transmission at a fixed location.
NOTE: If the Clear-Com system does not have AFH, then the base station should be set to operate in the region of the
2.4 GHz band where the Wi-Fi access point is not operating. For example, if the Wi-Fi access point is set to Wi-Fi channel
1, the base station should be set to operate in the ‘High’ band. If the Wi-Fi access point is set to channel 11, the base
should be set to operate in the ‘Low’.