Baicells Neutrino-224, Руководство по установке

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The process of a device moving from cell to cell and changing over from its serving eNB to a
neighbor (target) eNB is called handoff or handover*. The UE exchanges information with its
serving eNB to perform cell selection and reselection based on parameters which you will set
for each eNB. Refer to Figure 5-30.
*NOTE: The terms handoff and handover are used interchangeably in LTE.
Figure 5-30: Handoff
What the UE measures that determines cell selection and reselection is the Reference Signal
Received Power (RSRP) of the serving as well as neighboring eNBs. The measurements are sent
periodically to the serving eNB, which then determines if the UE would be better served by an
adjacent eNB.
The default settings in the
Mobility Parameter sub-menus (Figure 5-31) can be adapted to
most situations. Many of the mobility settings should be left with their default values. Any
modification should be determined only by experienced wireless professionals.
In terms of LTE to LTE handoff, only the
A1 , A3 , A5 , Measurement Control , Cell Selection
Parameter , and Cell ReSelection Parameter fields are used.
If the serving eNB determines that more than one adjacent eNB meets the RSRP event
thresholds, the
Cell Reselection settings will determine to which adjacent eNB the serving eNB
will hand off.
You will configure these mobility parameters for every adjacent eNB. To open one of the
threshold areas in the window, simply click on the heading, e.g.,
A1 Event Threshold , to display
the configuration fields. Table 5-19 describes each field. Click on
Save
to save the configuration
data.