FER issue after AMR FR activation This topic has 4 replies, 1 voice, and was last updated 11 years, 3 months ago by Ian. Viewing 5 posts - 1 through 5 (of 5 total) Author Posts 3rd September 2011 at 15:01 #67101 Hin GiuGuest FER has increased on all cells after activating AMR FR, (there is no major impact on any KPI), however we dont find such issue with AMR HR. 3rd September 2011 at 18:03 #67102 pixGuest hi, I would suspect that you have an issue with AMR FR + DTX. Try deactivating the DTX for AMR FR calls. The FER should be better thanks to AMR, not worse, so it has to be a kind of software issue. regards pix 4th September 2011 at 17:06 #67103 Hin GiuGuest hello pix, we thought of the same thing that is to deactivate DTX for AMR FR calls only but in Vain, can u plz suggest anyother valueable work around? 🙂 thank u 4th September 2011 at 19:13 #67104 pixGuest no, I don’t have any other idea. What you could try is to keep only one codec in the AMR FR codec set, ie. only the 12.2kbps. Check if it is better. Then add a second codec, for exampe, 10.x kbps. Check the FER. a) If NOK -> Remove the codec 12.2 and use only 10.x -> check again. b) If OK -> Then change this second codec to a lower one, and check the FER again. At this stage, you use only 2 codecs in the set. Then once all codecs are verified, you should start the same thing with 3 codecs. By the way, using only these 2 codecs : 12.2 and 7.4 is probably what I would apply on the field. You don’t really need 3 codecs, except if you want to spend a lot of time optimizing your C/I threshold for very little benefit. 12.2 : good VQ 7.4: good noise protection + TFO compatibility with AMR HR (in B11 only) regards pix 6th September 2011 at 00:14 #67105 IanGuest Hi Hin Giu, Have tried to remove DTX UL or DL ? or both ? I believe you are still in B10 and facing incompability between AMR and DTX ? BR Ian Author Posts Viewing 5 posts - 1 through 5 (of 5 total) The forum ‘Telecom Design’ is closed to new topics and replies.