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Re: LF: OPERA The new CW / QRSS replacement data mode

To: [email protected]
Subject: Re: LF: OPERA The new CW / QRSS replacement data mode
From: Andy Talbot <[email protected]>
Date: Mon, 2 Jan 2012 09:38:39 +0000
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In-reply-to: <24EF41C85642406DBC109E6B63190CBD@AGB>
References: <24EF41C85642406DBC109E6B63190CBD@AGB>
Reply-to: [email protected]
Sender: [email protected]
So what is the coding, the error correction, the decoding scheme.
Come on, in the amateur radio world there's no need for keeping such
things secret

You can't beat Shannon - ON/OFF in a particular bandwidth with decent
FEC will always give the same performance, so what are the innards of
this one?

Andy
www.g4jnt.com


On 2 January 2012 00:08, Graham <[email protected]> wrote:
> All,
>
>
>
> After  some  time  in development  the  136/500  version  of the  Opera
> data  mode  is  ready  for  experimental  use .
>
>
>
> Download  links  are  available  from  myself  or  Gary, G4WGT  as the
> versions  may  change  , these  may  also  change  ,
>
>
>
> Users  are  invited  to  join the  Opera  yahoo   group
> http://groups.yahoo.com/group/O_P_E_R_A_/?yguid=131323118
>
>
>
> At the  moment , spots  are  distributed to  other  OP users  on line  at
> the time ,. future intent  is to  link   to  the  PSK-Reporting  network
> and  for  a  HF version  and  possible  limited  QSO  mode , allowing
> under  the  noise  qso's  with  a simple  xtal  tx
>
>
>
> There  is a  on line  chat  mode to  facilitate  tests  etc
>
>
>
> The  software  is  available  for  all  , free  to  use  ,
>
>
>
> Happy  new year  to  all  and  good  luck
>
>
>
> 73-G ..
>
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> OPERA  The  new  CW/ QRSS  replacement   data mode
>
>
>
> There  is  always the  assumption that  all   armature  radio  stations
> can  effectively   translate  what  ever  new  soundcard  data  mode  that
> is  coded to  radio  frequency..
>
>
>
> The  question  I posed was  ‘What  about  those  who  cannot , and  only
> have  CW transmission  facility’s’? …
>
>
>
> Never did get a reply
>
>
>
> So  after a  long  exchange  of emails , the  concept  of  a  serial  data
> mode that  used only  one  tone  , on/off  keyed , with a  eye  on the
> qrss  system,  was  finally  discussed  and  coding  work  begun, an
> initial  statement  that in software , could  be  achieved  a lower  level
> of  detection  than that  required to  produce a  line  on a  spectrum  plot
> set the  scene for  a  what  was  originally  proposed to  be a  simple
> data  mode, turned into to  a  race to the  noise  floor.
>
>
>
>
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> OPERA
>
>
>
> Is  a totally   new   Data  / Beacon  mode ,  profiled  for the  136  and
> 500  bands  , with  HF  possibility’s   later  in the  project . The beacon
> mode is the version under test at the moment.
>
>
>
> Opera  was  designed  as an alternative  to the  QRSS  transmission  system
> and  provides  for a  limited  number of characters to  be  transmitted by
> a  serial  single  keyed  tone  , as  is  QRSS   or  live  CW, 6 at the
> moment.
>
>
>
> It is  live  ‘data’ mode and  there  is  no  requirement  for  time
> synchronisation  of the  tx/rx  station .
>
>
>
> The  mode  can  be  transmitted  by  any  transmitter  SSB/CW , there
> being  provided  a  keyed tone  and   Comm.  Port  CW   key interface
>
>
>
> There  is  a  windows ‘gui’ interface   and  the  requirement for   RX
> audio  feed,  based  round 1500 Hz , Tx  audio  at 1500 Hz may  also  be
> used to  drive  a  audio/rf conversion ,  changes  of  Tx  audio tone
> prevent collisions, and the  software scans  for a  slot of minimum noise .
> to  place the  TX carrier  in.
>
>
>
> If the  CW key option is  used, then the  Tx frequency  is  selected  by
> the  Tx master oscillator  only.
>
>
>
> Once a signal is decoded, the decode-spot is distributed to other
> web-connected   users, future development  will  link to the  PSK-Reporting
> network .
>
>
>
>
>
> OPERA  is coded  at the  moment  for  136  and  500 Khz   and  still  under
> development.
>
>
>
> As  a  basic  out  line  the  system (at the  moment) codes  the  six
> characters  of the  call  sign  and  transmits  them as a  serial  ‘pulse’
> train using  either  conventional  audio  to  RF  translation  , or  by
> the  use of  a  COM port  and  transistor  keying  cct  that  simply
> replaces the CW key ,
>
>
>
> Reception, as the  data   is  spread  out along  a  time  line , decoding
> is completed  during the  final  stages of the  transmission , due to  this
> ,,it  is not  possible  to  include a  receive  progress  monitor, however
> the  system  will  track and  decode  multiple transmissions  of  both time
> bases simultaneously
>
>
>
>
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> Transmit times are  used to  denote  the  mode
>
>
>
> 500 Khz
>
>
>
> 2        Minuets
>
> 16      Minuets
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> 136 Khz
>
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> 8          Minuets
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> 65        Minuets
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> S/N, The  mode  is  capable  of  decoding  under the  noise level  , beyond
> that  of  WSPR  or the  ROS-MF-2   system with a  maximum  data  loss of
> 33%  before  the  decode Fails.
>
>
>
> Opera 2     similar to WSPR
>
>
> Opera 8     6dB better than WSPR.
>
>
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> Opera 65   9 dB better than Opera8,
>
>
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>


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