Walt- thanks for the info. As I understand it (now), a claim about "robustness" must be accompanied by the identity of the simulation scheme, the S/N, and a measure of "band conditions". Any comparison, then, would need to be at duplicate conditions, or with a defined relationship between the various items. Very good. Bill-W4BSG
At 02:03 PM 7/12/2006 -0500, you wrote: >Oh there are perhaps several ways to determine robustness...but in all >cases, you need a stable test medium...in this case a simulator. > >You can take text or binary file and send the transmitted signal through a >simulator and measure the output. This can be the number of errors or >simply counting the number or character errors in a text file (see >http://www.johanforrer.net/SIMULR/index.html and >http://www.johanforrer.net/hfpsk.htm ) > >With many simulators you can set the signal level and "band" conditions such >as a Poor CCIR Channel and a SNR of -5 dB. The Poor CCIR Channel is a >specified set of signal/band conditions and of course the SNR is the ratio >of the signal to the noise. > >Thus for a Poor CCIR Channel (generally what you "expect on HF) and a signal >that is 5 dB below the noise, you might not expect any signal recovery. >However, there are several digital modes that can recover almost 100% of the >transmitted data under those conditions. > >The whole idea (at least for amateur radio operators) would seem to be the >use of a computer or new hardware digital modes in recovering as much data >possible from very weak signals. > >Walt/K5YFW > >-----Original Message----- >From: [email protected] [mailto:[EMAIL PROTECTED] >Sent: Tuesday, July 11, 2006 4:43 PM >To: [email protected] >Subject: RE: [digitalradio] Initiating QSO with ALE then PSK31 or Olivia >T exting, Other Traffic > > > >I plead ignorance (much!). Can you tell me how one measures "Robustness" >and assigns a discreet value to it? It seems to refer to communications >reliability, but I don't see how that can be assigned a discrete value, >with the inherent random factors that are present. >Help >Bill-W4BSG > >At 10:02 AM 7/11/2006 -0500, you wrote: > > >Hopefully someone can answer this question. > > > >What is the robustness (measured) and throughput for the newer digital >modes > >used for keyboard-to-keyboard operation. > > > >I know what it is for PSK31, PSK63, MFSK8/16, MT63...but what about all the > >other modes? > >Can someone provide a list? > > > >I would think that for any amateur radio communnications you would want to > >use the most robust mode with good keyboard-to-keyboard as well as file > >throughput. > > > >The two modes that come to my mind are MFSK16 and MT63. MT63 might not be >a > >good choice because of the latency. G4HPE has shown that MFSK16 is almost > >as robust as MT63 (in some cases perhaps more robust) and certainly is > >faster than most amateur radio operators can type. > > > >Thus to answer the instant question, it would seem that the mode to use for > >Ham ALE standards for digi text keyboarding, when QSOs are started via ALE > >selective calling would be one that is the most robust (very robust) and >has > >a throughput that is faster than most amateur radio operators can type. > > > >73, > > > >Walt/K5YFW > > > > > >-----Original Message----- > >From: [email protected] [mailto:[EMAIL PROTECTED] > >Sent: Tuesday, July 11, 2006 1:52 AM > >To: [email protected] > >Subject: [digitalradio] Initiating QSO with ALE then PSK31 or Olivia > >Texting, Other Traffic > > > > > >There is discussion going now on the HFLINK GROUP about > >using some convenient Ham ALE standards for digi text > >keyboarding, when QSOs are started via ALE selective calling. > > > >For example: HF ALE initiates the contact, then the > >operators switch over to BPSK31 at 1500Hz audio center > >frequency for texting. > > > >Other digi are being discussed, such as Olivia. > > > >For more information about ALE (HF Automatic Link Establishment) > >http://hflink.com > > > >HFLINK GROUP: > >http://groups.yahoo.com/group/hflink > > > >73---Bonnie KQ6XA > > > > > >. > > > > > > > > > > > > > > > >Need a Digital mode QSO? Connect to Telnet://cluster.dynalias.org > > > >Other areas of interest: > > > >The MixW Reflector : http://groups.yahoo.com/group/themixwgroup/ > >DigiPol: http://groups.yahoo.com/group/Digipol (band plan policy > >discussion) > > > > > >Yahoo! Groups Links > > > > > > > > > > > > > > > > > >[Non-text portions of this message have been removed] > > > > > > > > > >Need a Digital mode QSO? Connect to Telnet://cluster.dynalias.org > > > >Other areas of interest: > > > >The MixW Reflector : http://groups.yahoo.com/group/themixwgroup/ > >DigiPol: http://groups.yahoo.com/group/Digipol (band plan policy >discussion) > > > > > >Yahoo! Groups Links > > > > > > > > > >Bill Aycock - W4BSG >Woodville, Alabama > > > > > >Need a Digital mode QSO? Connect to Telnet://cluster.dynalias.org > >Other areas of interest: > >The MixW Reflector : http://groups.yahoo.com/group/themixwgroup/ >DigiPol: http://groups.yahoo.com/group/Digipol (band plan policy >discussion) > > >Yahoo! Groups Links > > > > > > > > >[Non-text portions of this message have been removed] > > > > >Need a Digital mode QSO? Connect to Telnet://cluster.dynalias.org > >Other areas of interest: > >The MixW Reflector : http://groups.yahoo.com/group/themixwgroup/ >DigiPol: http://groups.yahoo.com/group/Digipol (band plan policy discussion) > > >Yahoo! Groups Links > > > > Bill Aycock - W4BSG Woodville, Alabama Need a Digital mode QSO? Connect to Telnet://cluster.dynalias.org Other areas of interest: The MixW Reflector : http://groups.yahoo.com/group/themixwgroup/ DigiPol: http://groups.yahoo.com/group/Digipol (band plan policy discussion) Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/digitalradio/ <*> To unsubscribe from this group, send an email to: [EMAIL PROTECTED] <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
