aboutsummaryrefslogtreecommitdiffstats
path: root/doc
diff options
context:
space:
mode:
authorVadim Yanitskiy <axilirator@gmail.com>2019-07-07 19:58:48 +0700
committerlaforge <laforge@gnumonks.org>2019-07-21 13:51:57 +0000
commit9649a42d5a3c24a21c14bb9f54e7c34a398da7b1 (patch)
tree66363546279249833a49769a609a7989a4e9358f /doc
parentdb6c7863506ea3685d73df26c45723073ee1f109 (diff)
Clarify and refactor link quality (C/I) handling
The radio link quality is defined by C/I (Carrier-to-Interference ratio), which is computed from the training sequence of each received burst, by comparing the "ideal" training sequence with the actual (received) one. Link quality measurements are used by L1SAP to filter out "ghost" Access Bursts, and by the link quality adaptation algorithms. One can define minimum link quality values using the VTY interface. On the VTY interface we expect integer C/I values in centiBels (cB, 10e-2 B), while the internal structures are using float values in deciBels (dB, 10e-1 B). Some PHYs (sysmo, octphy, oc2g, and litecell15) expose C/I measurements in deciBels, while on the L1SAP interface we finally send then in centiBels. Let's avoid this confusion and stick to a single format, that will be used by the internal logic of OsmoBTS - integer values (int16_t) in centiBels. This will give us the range of: -32768 .. 32767 centiBels, or -3276.8 .. 3276.7 deciBels, which is certainly sufficient. Change-Id: If624d6fdc0270e6813af8700d95f1345903c8a01
Diffstat (limited to 'doc')
-rw-r--r--doc/manuals/vty/bts_vty_reference.xml8
1 files changed, 4 insertions, 4 deletions
diff --git a/doc/manuals/vty/bts_vty_reference.xml b/doc/manuals/vty/bts_vty_reference.xml
index b50ac1ba..4697ee79 100644
--- a/doc/manuals/vty/bts_vty_reference.xml
+++ b/doc/manuals/vty/bts_vty_reference.xml
@@ -1613,14 +1613,14 @@
</command>
<command id='min-qual-rach &lt;-100-100&gt;'>
<params>
- <param name='min-qual-rach' doc='Set the minimum quality level of RACH burst to be accpeted' />
- <param name='&lt;-100-100&gt;' doc='C/I level in tenth of dB' />
+ <param name='min-qual-rach' doc='Set the minimum link quality level of Access Bursts to be accepted' />
+ <param name='&lt;-100-100&gt;' doc='C/I (Carrier-to-Interference) ratio in centiBels (10e-2 B or 10e-1 dB)' />
</params>
</command>
<command id='min-qual-norm &lt;-100-100&gt;'>
<params>
- <param name='min-qual-norm' doc='Set the minimum quality level of normal burst to be accpeted' />
- <param name='&lt;-100-100&gt;' doc='C/I level in tenth of dB' />
+ <param name='min-qual-norm' doc='Set the minimum link quality level of Normal Bursts to be accepted' />
+ <param name='&lt;-100-100&gt;' doc='C/I (Carrier-to-Interference) ratio in centiBels (10e-2 B or 10e-1 dB)' />
</params>
</command>
<command id='nominal-tx-power &lt;0-100&gt;'>