MIME-Version: 1.0
In-Reply-To: <BF4A524700075746A6467658DFC7102CB0B68CCDB0@ICTS-S-EXC2-CA.luna.kuleuven.be>
References: <BF4A524700075746A6467658DFC7102CB0B68CCDB0@ICTS-S-EXC2-CA.luna.kuleuven.be>
Date: Wed, 8 Feb 2012 16:59:03 +0000
Message-ID: <CAA8k23RcoXwP2JQBGOGpCe1kcgmv8=taMMqWcMEEVukvj9EW=g@mail.gmail.com>
From: Andy Talbot <andy.g4jnt@gmail.com>
To: rsgb_lf_group@blacksheep.org
Subject: Re: LF: QRSS3 "challenge" results
Content-Type: text/plain; charset=ISO-8859-1
Content-Transfer-Encoding: quoted-printable
Sender: owner-rsgb_lf_group@blacksheep.org
Precedence: bulk
Reply-To: rsgb_lf_group@blacksheep.org
X-AOL-SCOLL-URL_COUNT: 0  
X-AOL-SCOLL-AUTHENTICATION: mail_rly_antispam_dkim-m245.1 ; domain : gmail.com DKIM : pass  
x-aol-sid: 3039ac1d40cd4f32b1981a03
X-AOL-IP: 195.171.43.25
X-AOL-SPF: domain : blacksheep.org SPF : none


Hi RIk -

one comment / question I have ...
When you generasted the Opera and WSPR audio files, did you take into
account that Opera should be compared using the mean power?  With its
50% duty cycle, this means an Opera Tx has to have twice the power
rating of one running WSPR for equal S/N ratios.

If you used peak power (ie. the same transmitter amplitude), the curve
plotted for Opera will have to move 3dB to the right, making it more
comparable with WSPR - and then more as one would expect.

Given the similarity of the error correction overhead for Opera and
WSPR,  and nearly matching symbol rate for OP2 ,and that OOK and FSK
have comparable error rates for the same mean power, suggests the two
modes should give roughly similar performance.

Only 27 responses, that doesn't seem very many compared with the
numbers that monitor this reflector.

Andy  G4JNT


On 8 February 2012 16:00, Rik Strobbe <Rik.Strobbe@fys.kuleuven.be> wrote:
> Dear=A0all,
>
> the=A0results of the "QRSS3 challenge"=A0can=A0be=A0found at
> http://on7yd.strobbe.eu/QRSS/
> Hit=A0refresh=A0if=A0you=A0still=A0see the=A0old challenge.
>
> Thanks=A0to all=A0who=A0participated !
>
> 73, Rik=A0=A0ON7YD - OR7T
>
> ________________________________
> Van: Rik Strobbe
> Verzonden: donderdag 2 februari 2012 18:17
> Aan: rsgb_lf_group@blacksheep.org
> Onderwerp: QRSS3 "challenge"
>
> Dear=A0all,
>
>
>
> as=A0mentioned=A0some=A0days=A0ago I=A0generated a=A0whole series of Oper=
a,=A0WSPR
> and=A0QRSS3 audio=A0with a=A0known SNR.
>
> For Opera and=A0WSPR=A0it was easy to=A0determine the=A0lowest=A0SNR=A0fo=
r a proper
> decode.=A0But=A0for=A0QRSS3=A0it is=A0much more=A0difficult as=A0it=A0dep=
ends=A0on the
> operators "sharp eye".=A0It must=A0be=A0somewhere in the range of -24 to =
-28dB=A0SNR
> (@=A02.5kHz BW).
>
> Today=A0I=A0did put all the=A0QRSS3 screenshots in=A0this range in a
> website,=A0where=A0you=A0can=A0fill in=A0what=A0you=A0see (decode)=A0for=
=A0each screenshot.
>
> I=A0would=A0like to invite all of=A0you to=A0give=A0it a=A0try and=A0send=
 me the=A0results
> (the more=A0entries the=A0better the statistics).
>
> After=A0some time=A0(Feb 10th)=A0will put all=A0results=A0into=A0some=A0n=
ice tables
> and=A0graphs and=A0make=A0them available.
>
> Of=A0course=A0no=A0personal (individual)=A0results=A0will=A0be published.=
=A0But=A0based=A0on
> the=A0results=A0every participant (who=A0keeps=A0his results)=A0can=A0see=
=A0where=A0he ends.
>
>
>
> The "QRSS3 Challenge"=A0can=A0be=A0found at http://on7yd.strobbe.eu/QRSS/
>
>
>
> 73, Rik=A0=A0ON7YD - OR7T