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<p style="margin-bottom: 0in;"><span
style="background: transparent none repeat scroll 0% 0%; -moz-background-clip: border; -moz-background-origin: padding; -moz-background-inline-policy: continuous;">Hi,<br>
</span></p>
<p style="margin-bottom: 0in;"><span
style="background: transparent none repeat scroll 0% 0%; -moz-background-clip: border; -moz-background-origin: padding; -moz-background-inline-policy: continuous;">Jean-Samuel
and me developed an advanced handover algorithm for OpenBSC. Before
implementing it, we would like to get any feedback, so I decided to
post it in this mailing list. The document that describes the algorithm
can be downloaded at: </span><a class="moz-txt-link-freetext" href="http://home.eversberg.eu/handover-algorithm-v2.3.pdf">http://home.eversberg.eu/handover-algorithm-v2.3.pdf</a><br>
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<p style="margin-bottom: 0in;">Regards,<br>
</p>
<p style="margin-bottom: 0in;">Andreas</p>
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<br>
Handover
shall ensure that the mobile station is always on the best cell
during a call. This results in best speech quality and allows a lower
TX level (up-link) to save battery and reduce interference. Sometimes
this is not desirable, especially if a cell with large coverage
becomes congested after handover. In this situation it makes sense to
balance the usage between cells to prevent congestion. If a cell is
congested, one or several mobile stations need to be handovered to a
different cell, even if that cell is not the best cell for these
mobile station. In case that a mobile station needs to handover to
prevent a loss of radio link, it makes sense to handover it to a cell
that is congested afterwards. In this situation, a different mobile
station on the congested target cell must be handovered to a
non-congested neighbor cell, to solve or balance the congestion.<br>
</span>
<p style="margin-bottom: 0in;"><span
style="background: transparent none repeat scroll 0% 0%; -moz-background-clip: border; -moz-background-origin: padding; -moz-background-inline-policy: continuous;">In
order
to negotiate used codec and TCH rate during call setup,
Immediate Assignment shall assign an SDCCH channel, if available.
After negotiation is complete, assignment to the available TCH slot
is made.<br>
<br>
</span></p>
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