Gustavo Santos
2011-Oct-01 22:02 UTC
[asterisk-users] Converting dahdi_monitor unit to dbm0
Hello, I need to convert the dahdi_monitor output to dBm0, so I can measure Echo Return Loss in dB. I've read a formula that calculate S(k) in ITU-T G.168 recommendation, where S(k) is the signal level in dBm0. Can I use this formula to convert it? If yes, what value should I use to the number of samples if I want to convert a single output from dahdi_monitor? -- Thanks in advance, Gustavo Santos. -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.digium.com/pipermail/asterisk-users/attachments/20111001/a297df29/attachment.htm>
Tzafrir Cohen
2011-Oct-17 09:38 UTC
[asterisk-users] Converting dahdi_monitor unit to dbm0
On Sat, Oct 01, 2011 at 07:02:48PM -0300, Gustavo Santos wrote:> Hello, > I need to convert the dahdi_monitor output to dBm0, so I can measure Echo > Return Loss in dB.dahdi_monitor defaults to recording a signed linear PCM file. But latest versions (as of 2.4.0) will output a wav file if the extension of the file is ".wav". There are several options to get separat Rx and Tx streams. Capital letter options give you a pre-echocanceller signal. -- Tzafrir Cohen icq#16849755 jabber:tzafrir.cohen at xorcom.com +972-50-7952406 mailto:tzafrir.cohen at xorcom.com http://www.xorcom.com iax:guest at local.xorcom.com/tzafrir