https://projects.osmocom.org/https://projects.osmocom.org/favicon.ico?16647414092018-07-15T05:20:31ZOpen Source Mobile CommunicationsOsmoBTS - Feature #1855: provide actual BER or C/I values from osmo-bts-trx into the PCUhttps://projects.osmocom.org/issues/1855?journal_id=103012018-07-15T05:20:31Zlaforge
<ul><li><strong>Related to</strong> <i><a class="issue tracker-1 status-3 priority-3 priority-high3 closed" href="/issues/3395">Bug #3395</a>: Uplink CS/MCS control is broken osmo-pcu is used with osmo-bts-trx/osmo-trx</i> added</li></ul> OsmoBTS - Feature #1855: provide actual BER or C/I values from osmo-bts-trx into the PCUhttps://projects.osmocom.org/issues/1855?journal_id=109572018-08-24T15:49:14Zlaforge
<ul><li><strong>Related to</strong> <i><a class="issue tracker-1 status-3 priority-1 priority-lowest closed" href="/issues/1616">Bug #1616</a>: osmo-bts-trx / osmo-bts-octphy doesn't provide C/I information to PCU </i> added</li></ul> OsmoBTS - Feature #1855: provide actual BER or C/I values from osmo-bts-trx into the PCUhttps://projects.osmocom.org/issues/1855?journal_id=109592018-08-24T15:55:17Zlaforge
<ul></ul> OsmoBTS - Feature #1855: provide actual BER or C/I values from osmo-bts-trx into the PCUhttps://projects.osmocom.org/issues/1855?journal_id=117502018-09-30T10:59:18Zlaforge
<ul><li><strong>Priority</strong> changed from <i>Normal</i> to <i>High</i></li></ul> OsmoBTS - Feature #1855: provide actual BER or C/I values from osmo-bts-trx into the PCUhttps://projects.osmocom.org/issues/1855?journal_id=122942018-10-20T19:33:07Zlaforge
<ul><li><strong>Assignee</strong> set to <i>tnt</i></li></ul> OsmoBTS - Feature #1855: provide actual BER or C/I values from osmo-bts-trx into the PCUhttps://projects.osmocom.org/issues/1855?journal_id=141382019-04-25T15:11:42Zlaforge
<ul></ul><p><a class="user active" href="https://projects.osmocom.org/users/12">tnt</a>, any news here?</p>
<p>I just re-investigated this topic with Lynxis. The C/I value can be computed from the training sequence of each burst, where we can compare the "ideal" training sequence with the actual training sequence and then express that in dB.</p>
<p>As osmo-trx is already doing the correlation againt the training sequence, it may make sense to do it there. In fact, detectBurst() appears to already return the complex normalized amplitude of the correlation of the training sequence, which is probably almost exactly the value we're interested in here? If this is true, we should probably extend the trx protocol to provide the data to osmo-bts-trx, rather than having osmo-bts-trx do another correlation against the training sequence...</p> OsmoBTS - Feature #1855: provide actual BER or C/I values from osmo-bts-trx into the PCUhttps://projects.osmocom.org/issues/1855?journal_id=144372019-05-14T16:25:42Ztnt
<ul></ul><p>I got the math worked out that computes a value that might be the C/I ... (at least it seems to have the right properties and it's also in the right range of value).</p>
<p><a class="external" href="http://git.osmocom.org/osmo-trx/commit/?h=tnt/ci&id=d40f11962a4d0e2c0ea9e3bde4c568c6c4b62a12">http://git.osmocom.org/osmo-trx/commit/?h=tnt/ci&id=d40f11962a4d0e2c0ea9e3bde4c568c6c4b62a12</a></p>
<p>How/Where to actually pass it all the way to the PCU is TBD.</p> OsmoBTS - Feature #1855: provide actual BER or C/I values from osmo-bts-trx into the PCUhttps://projects.osmocom.org/issues/1855?journal_id=144382019-05-14T18:06:22Zipse
<ul></ul><p>tnt wrote:</p>
<blockquote>
<p>I got the math worked out that computes a value that might be the C/I ... (at least it seems to have the right properties and it's also in the right range of value).</p>
<p><a class="external" href="http://git.osmocom.org/osmo-trx/commit/?h=tnt/ci&id=d40f11962a4d0e2c0ea9e3bde4c568c6c4b62a12">http://git.osmocom.org/osmo-trx/commit/?h=tnt/ci&id=d40f11962a4d0e2c0ea9e3bde4c568c6c4b62a12</a></p>
<p>How/Where to actually pass it all the way to the PCU is TBD.</p>
</blockquote>
<p>Great to finally see some progress here :)</p>
<p>By "right properties" - have you tested increasing interference to check that it's correctly accounted?</p>
<p>Do you have test vectors which could be used as a test case when/if someone decides to write an optimized version of the code?</p> OsmoBTS - Feature #1855: provide actual BER or C/I values from osmo-bts-trx into the PCUhttps://projects.osmocom.org/issues/1855?journal_id=144392019-05-14T18:42:06Ztnt
<ul></ul><p>I checked that :<br /> - It's independent of scaling (so if you multiply the input vector by any value, it doesn't change the result, except for 'float' precision of course).<br /> - Adding noise tends to decrease the value. I say "tends" because it's all based on only 16 samples ... which doesn't provide much averaging at all, so I ran it through thousands of runs, adding noise to some off the air captures and just looked at the shape of the graph.</p> OsmoBTS - Feature #1855: provide actual BER or C/I values from osmo-bts-trx into the PCUhttps://projects.osmocom.org/issues/1855?journal_id=144722019-05-16T15:19:18Ztnt
<ul></ul><p>I think it was <a class="user active" href="https://projects.osmocom.org/users/30187">pespin</a> and <a class="user active" href="https://projects.osmocom.org/users/67">fixeria</a> were discussing how to extend the TRX protocol ?<br />Just ping me when you came up with that extended protocol and where to plug that value ...</p> OsmoBTS - Feature #1855: provide actual BER or C/I values from osmo-bts-trx into the PCUhttps://projects.osmocom.org/issues/1855?journal_id=144742019-05-16T19:55:24Zfixeria
<ul><li><strong>Blocked by</strong> <i><a class="issue tracker-2 status-7 priority-2 priority-default" href="/issues/4006">Feature #4006</a>: TRX protocol: wind of change</i> added</li></ul> OsmoBTS - Feature #1855: provide actual BER or C/I values from osmo-bts-trx into the PCUhttps://projects.osmocom.org/issues/1855?journal_id=149932019-06-26T21:13:49Zfixeria
<ul><li><strong>Tracker</strong> changed from <i>Bug</i> to <i>Feature</i></li><li><strong>Status</strong> changed from <i>New</i> to <i>In Progress</i></li><li><strong>Assignee</strong> changed from <i>tnt</i> to <i>fixeria</i></li><li><strong>Priority</strong> changed from <i>High</i> to <i>Urgent</i></li><li><strong>% Done</strong> changed from <i>0</i> to <i>80</i></li></ul><p>Please see: <a class="external" href="https://gerrit.osmocom.org/#/c/osmo-bts/+/14613/">https://gerrit.osmocom.org/#/c/osmo-bts/+/14613/</a></p> OsmoBTS - Feature #1855: provide actual BER or C/I values from osmo-bts-trx into the PCUhttps://projects.osmocom.org/issues/1855?journal_id=150522019-07-03T06:56:54Zfixeria
<ul><li><strong>Status</strong> changed from <i>In Progress</i> to <i>Feedback</i></li><li><strong>% Done</strong> changed from <i>80</i> to <i>90</i></li></ul><p>I finally wrote a TTCN-3 test case:</p>
<p><a class="external" href="https://gerrit.osmocom.org/#/c/osmo-ttcn3-hacks/+/14660/">https://gerrit.osmocom.org/#/c/osmo-ttcn3-hacks/+/14660/</a></p>
<p>Waiting for all changes to be merged now...</p> OsmoBTS - Feature #1855: provide actual BER or C/I values from osmo-bts-trx into the PCUhttps://projects.osmocom.org/issues/1855?journal_id=151552019-07-16T08:13:35Zfixeria
<ul><li><strong>% Done</strong> changed from <i>90</i> to <i>100</i></li></ul><p>All required changed have been merged. The TTCN-3 test case passes.</p>
<p>P.S. I cannot mark it as resolved for some reason.</p> OsmoBTS - Feature #1855: provide actual BER or C/I values from osmo-bts-trx into the PCUhttps://projects.osmocom.org/issues/1855?journal_id=151722019-07-16T17:13:12Zfixeria
<ul><li><strong>Blocked by</strong> deleted (<i><a class="issue tracker-2 status-7 priority-2 priority-default" href="/issues/4006">Feature #4006</a>: TRX protocol: wind of change</i>)</li></ul> OsmoBTS - Feature #1855: provide actual BER or C/I values from osmo-bts-trx into the PCUhttps://projects.osmocom.org/issues/1855?journal_id=151732019-07-16T17:13:54Zfixeria
<ul><li><strong>Status</strong> changed from <i>Feedback</i> to <i>Resolved</i></li></ul> OsmoBTS - Feature #1855: provide actual BER or C/I values from osmo-bts-trx into the PCUhttps://projects.osmocom.org/issues/1855?journal_id=264392023-03-21T13:02:25Zfixeria
<ul><li><strong>Related to</strong> <i><a class="issue tracker-1 status-3 priority-2 priority-default closed" href="/issues/5954">Bug #5954</a>: ttcn3-bts-test: TC_pcu_data_ind_lqual_cb is failing</i> added</li></ul>