[pskmail] Re: integrating Winmor TNC
- From: karel Fassotte <karel.fassotte@xxxxxxxxx>
- To: pskmail@xxxxxxxxxxxxx
- Date: Fri, 28 Jan 2011 08:49:00 -0500
See the attachment with specifications.
Karel
2011/1/28 karel Fassotte <karel.fassotte@xxxxxxxxx>
> Hello all, Rein,
> To make real comparison with PSKmail we have to consider the wave form and
> the way the waveform choise is handled.
>
> The WINMOR protocol uses basic OFDM (Orthogonal Frequency Division
> Multiplexing) modulation and a number of modulation modes and error
> correction
> schemes to adapt to changing channel conditions.
> There are currently 2 operating bandwidths of 500 and 1600 Hz (@ 26 db
> below peak power output:
> -500 Hz BW 2 carriers 46.875 Baud 4FSK or 93.75 baud PSK using TCM
> 4PSK, 8PSK or 16PSK
> -1600 Hz BW 8 carriers 46.875 Baud 4FSK or 93.75 baud PSK using TCM
> 4PSK, 8PSK or 16PSK.
> I tested winmor in a NVIS link, without any interferece in Ecuador and
> 2.5KB message was transfered in 80 seconds. No only once
> but concequently. Without compression. In my opinion the OFDM multicarrier
> PSK waveform is more effective than the BPSK, PSK mail is using.
> What I am asking is to consider integrating these waveforms in PSKmail, to
> make it even more robust and faster.
> The specifications of winmor are known, the software is closed code, but
> may the binary of the TNC can be bounded to PSKmail as FLDIGI modem does.
>
> OK go ahead.
>
> greetings
> HC1AKP
>
>
>
> 2011/1/28 Rein Couperus <rein@xxxxxxxxxxxx>
>
> Maybe I can throw something in on this subject, as I have some
>> hands-on experience with pskmail....
>>
>> It really looks like PSK500 is the fastest PSK mode which can be effective
>> on HF,
>> the setup we have now is often too optimistic, and the link falls back to
>> PSK500R
>> unless the channel is absolutely clean. When this happens, the net
>> throughput
>> goes up to max. 1600 bytes/minute (max. measured 1692 bytes/min) including
>> ARQ
>> overhead. In case of file transfers this is compressed, so actually the
>> throughput is more in the order of 2kB/min, which is the value Karel
>> needs.
>> We are seeing this in the seldom case that we have a clean channel
>> As long as there is no requirement for mode change, RSID is not used.
>> Binary attachments are integrated in pskmail.
>>
>> When we are looking at clean links (these don't exist in EU) we could get
>> some more
>> throughput by allowing frames of more than 8 blocks, which would increase
>> the
>> throughput slightly.
>>
>> And of course if somebody can supply us with an open source fast modem for
>> fldigi
>> we could get talking...
>>
>> 73,
>>
>> Rein EA/PA0R/M
>>
>>
>>
>>
>>
>> >Hola Karel,
>> >
>> >My reply to your comments between {} below.
>> >
>> >Regards,
>> >
>> >John
>> >
>> >On Fri, Jan 28, 2011 at 11:10 AM, karel Fassotte
>> > wrote:
>> >> Hello John,
>> >> I will comment below.
>> >>
>> >> 2011/1/27 John Douyere
>> >>>
>> >>> Hola Karel,
>> >>>
>> >>> There are three key design objectives in the Pskmail project that
>> >>> relate to your questions:
>> >>>
>> >>> 1. Open source (right its no open source9 {I am not sure what you mean
>> here but ALL components of Pskmail ARE open source: Fldigi, the server in
>> Perl and the Client in Java. Therefore anybody with special requirements can
>> get into the code and modify as In my case - I came in a few years after the
>> start of the project and have contributed a number of items}
>> >>>
>> >>> 2. Narrow band (less than 500 Hz). (why ?) {so that we do not use
>> unnecessary bandwidth which has been a key complaint by Ham radios with
>> wider systems and are able to use all the narrow segment of the bands
>> (including the very important 30M for Europe)}
>> >>>
>> >>> 3. Solid link even in the presence of QRM/QRN (NVIS links are very
>> stroung
>> >>> little interference) {I don't know in Equador but here we have
>> thunderstorm activities, mainly in summer, that create significant QRN even
>> when the signals are S9+10 as is common in NVIS conditions here}
>> >>>
>> >>> The Winmor protocol is available as a software TNC (like Fldigi) but
>> >>> unfortunately only under Windows. So that excludes for the moment
>> >>> having it linked to Pskmail. (right)
>> >>>
>> >>> On the speed aspect there would be some work required to increase the
>> >>> speed further with say 2PSK or 4 PSK (e.g. 2 or 4 PSK500 or PSK500R
>> >>> modulations in parallel). That would not be that hard to do in Fldigi,
>> >>> but the timing will become more critical in Pskmail as it was more
>> >>> designed to accommodate very different (and some slow) digital mode
>> >>> timings rather than a fixed and precise timing between client and
>> >>> server. (that could be a solution. However I liked the very ffast and
>> >>> efficient turn arround of Winmor)
>> >>>
>> >>> So probably the issue at present is more to understand the need for
>> >>> faster speed as the design objectives has served us well until now I
>> >>> believe. (yes that might be the case but link build up and conecting
>> >>> speed, addaptive is of great advantage for a quick handling of mail.
>> Speed
>> >>> is also an issue) A mail of 1KB should be transfered and handled in a
>> >>> minute. {What happens if it is delivered in two minutes? What
>> percentage of the total response time is that?}
>> >>>
>> >>> Please note that Pskmail (at least in recent versions) will
>> >>> automatically adapt it's speed depending on the conditions, from THOR8
>> >>> to PSK500 and in my personal experience has been able to establish
>> >>> links several times when I could not with Winmor from my same portable
>> >>> setup. (I dont have the same experience. I have no problem linking
>> Winmor
>> >>> on my links)
>> >>>
>> >>> Of course it could be a difference in the server's setup since they
>> >>> are separated by several kilometers and don't run the same antennas,
>> >>> but that is my experience.(My conexions are NVIS links up to about
>> 1000km)
>> >>>
>> >>> What happens often is that the link is not symmetric, either because
>> >>> the portable station is running low power and/or has compromise
>> >>> antennas, or the server (which normally runs high power - say 50 watts
>> >>> - and has good antennas) has local QRM. (maybe an item)
>> >>>
>> >>> That is why Pskmail will TX and RX in different modes and adapt each
>> >>> individually to the link quality.(I understands but that takes time
>> and
>> >>> time is critical for emergency communications)
>> >>>
>> >>> I have several time run QRP power (FT-817) with a dipole in NVIS
>> >>> conditions (which I believe represents the most common situation for
>> >>> disaster conditions) and had very good downlink from the server and
>> >>> poor uplink to it, but Pskmail did it's job nicely almost every time.
>> (I
>> >>> hope it can be faster and better)
>> >>>
>> >>> When the link is good the PSK500 modulation will provide an 800 words
>> >>> per minute raw speed, and taking into account the compression of text
>> >>> messages (about 2 x for text) and the overhead of the Pskmail protocol
>> >>> we should see net exchanges of about 200 to 400 words per minute or
>> >>> above 70Kb of data per hour. That is a lot of data exchanged I feel.
>> (for
>> >>> bigger files I would use another protocol 188-110, this is slower
>> bulding up
>> >>> the link but has much faster data troughput uo to 2Kb/s) {If speed is
>> that critical, have you looked at RFSM-8000 which uses MIL-STD 188-110A /
>> MIL-STD 188-110B modulation. It runs normally under windows but I have been
>> able to run the older version - RFSM-2400 under Wine on a Ubuntu PC, so it
>> may work with RFSM-8000 too. You can get a free trial license from their web
>> site, if this project is still active}.
>> >>>
>> >>> In my experience also, the psk modulations (as used in Fldigi and
>> >>> Wiinmor) are not the most robust due to phase shifting and selective
>> >>> fading that is characteristic of that propagation mode. In that case
>> >>> the fsk modes (MFSK and THOR for example) provide much lower error
>> >>> rates. (Winmore is fast adaptive and uses 5Khz. bandwith or 1,6Khz.
>> >>> Bandwith using multi carriers OFDM PSK)
>> >>>
>> >>> I have seen many times a slower but more reliable link (in MFSK for
>> >>> example) providing a higher net data rate than a fast, lest reliable
>> >>> link with many repeats. (Looking for a solution for a good NVIS link,
>> not
>> >>> for links wit a lot of QRM, QSB, speed should be maximum 1300b/s)
>> >>>
>> >>> What format do you expect your emergency network to take: NVIS or long
>> >>> distance, what type of stations (fixed, high power, good antennas OR
>> >>> portable low power, compromise antennas), how many stations, how many
>> >>> messages, of what size, what type of message content (text or binary
>> >>> data). (NVIS uo to 1500 km, 50 watts of power 100% duty cycle, a good
>> NVIS
>> >>> dipole on several frequencies. About 20 stations, 1K, max. 2KB
>> messages.
>> >>> Messages usualy are text based but could contain binary attachments
>> (small)
>> >
>> >{what volume of messages? as that will give you the expected channel
>> >usage and also the average latency of the messages. I propose you
>> >start from there and then see what the numbers tell you in regards of
>> >the speed you need, rather than starting from the speed itself}.
>> >
>> >{In the digitalradio Yahoo group there are a few people who have setup
>> >such networks and can give you good feedback. I noticed that speed
>> >what not their main criterion, but they focussed on ease of use,
>> >reliability of communication, ability to broadcast messages to
>> >multiple stations etc. Maybe you can ask some questions there too.
>> >They have used Fldigi with and Flwrap and Flmsg. Instead of relying on
>> >ARQ for safe delivery of their messages they use modes with strong FEC
>> >like MT63 and Olivia together with the tools above and that seems to
>> >work well for them}.
>> >
>> >>>
>> >>> These are all factors that are important in your selection of the best
>> >>> solution.
>> >>>
>> >>> Hope this helps.
>> >>>
>> >>> Regards,
>> >>>
>> >>> John (VK2ETA)
>> >>
>> >> Please go on suggesting, I might not the only one thats looking for
>> this
>> >> solution.
>> >> Greetings
>> >> and thanks
>> >> Karel (HC1AKP)
>> >>>
>> >>> On Fri, Jan 28, 2011 at 3:03 AM, karel Fassotte
>> >>> wrote:
>> >>> > Hello all,
>> >>> > I have been investigating for some time now solutions for a
>> emergency
>> >>> > network in Ecuador I also have been testing pskmail. I think it is
>> >>> > allright
>> >>> > but I would like to have more and faster modem waveforms included.
>> >>> > FLDIGI is
>> >>> > a nice multiwave form software modem, but for mespeed could be
>> faster. I
>> >>> > have been testing the WINMOR TNC of Winlink.
>> >>> > My results are that the WINMOR TNC is very adecuate and hast
>> handling
>> >>> > maximizing overall troughput. This is of big interest for an
>> emergency
>> >>> > network. Many small (1KB) messages should be handled.
>> >>> > The RMS message terminal is also very easy to use.
>> >>> > This is all closed software, only windows untill now. I am not
>> >>> > interested in
>> >>> > windows, but I am interested in solutions for open code with maximum
>> >>> > funcionality and easy use.
>> >>> > Can this WINMOR TNC be integrated in pskmail? This would realy be a
>> >>> > great
>> >>> > improvement over the existing FLDIGI modem.
>> >>> > Do exists other soundcard modems that have the same specs as the
>> WINMOR
>> >>> > TNC?
>> >>> > Please let me know.
>> >>> > greetings, 73
>> >>> > Karel Fassotte
>> >>> > HC1AKP
>> >>> >
>> >>> >
>> >>> >
>> >>>
>> >>
>> >>
>> >
>>
>>
>
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