[RTTY] Estimating increase in bandwidth/interfeerence from Winlink if RM11708 is approved

RTTY rtty at contesting.com
Thu Apr 17 16:56:36 EDT 2014


Taking the existing Winlink stations and transmitting bandwidths and
changing the bandwidths to 2.8 KHz, we can get a idea on the future increase
in consumed bandwidth/interference if RM11708 is approved.   Here are the
steps used in this analysis:

 

1.  Take the published Winlink call/frequency/mode list.  Determine the
current bandwidth and convert it into a spectral density format where we
total the total number of stations transmitting every 100 HZ.

 

2.  Repeat step one using a 2.8 KHz bandwidth for each station.

 

3.  Import into Excel, sum from 7.060 to 7.100 MHz.   

 

The result is:   3.6 times more spectral bins used if 2.8 KHz becomes the
standard.     A graph displaying the results can be found at:
http:\\64.128.19.154\Images\RM11708-1.jpg      

 

The X axis is frequency and the Y Axis is the total stations transmitting in
each 100 HZ bin.

     

Assumptions:   

    1. The processing was only ran against US Winlink stations.

    2. Only Winlink frequencies were analyzed.   Other current and future
digital waveforms (ALE, etc)  are not included.

   3.  Modulation is USB, no offset

    4.  Current Winlink bandwidths are:  Pactor 4:  2.4,  Pactor 3:  2.4,
Pactor 2:  .6, WINMOR 1600:  1.6, WINMOR 500  .5, and  Robust Packet: .5

 

Terry AB5K

 

 

 

 



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