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<p class="MsoNormal">Good afternoon Colin,</p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Here is my description of the what I understood to be our latest definition for FWD/RTN COMS STAR/END events.</p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">The forward and Return Communication Start and End events are used by the provider to specify the possible start and end of communication service windows to a user platform, relative to any and all limitations and constraints under which
that provider can execute user services. The specific limitations and constraints are not implied and are left up to the provider to consider, so long as the user platform can plan and request any service whose Start and End times are contained (inclusive)
within the timeframe bounded by the COMS_START and COMS_END events.</p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Typical limitations and constraints accounted for when defining the COMS_START and COMS_END events are constraints associated with antenna elevation, cable wrap, visibility masks, slew rates, etc. Constraints that are specific to a service
type or a user mission such as limitations due to service frequency band or a user’s platform communication equipment, or constraints defined by a particularService Agreement, are not typically included in the COMS_START and COMS_END events.</p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">The table of events could read as follows:</p>
<p class="MsoNormal"><o:p> </o:p></p>
<table class="MsoNormalTable" border="1" cellspacing="0" cellpadding="0" style="border-collapse:collapse;border:none">
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<td width="154" valign="top" style="width:1.6in;border:solid windowtext 1.0pt;padding:0in 5.4pt 0in 5.4pt">
<p class="MsoNormal"><span style="font-size:10.0pt">Ret-Coms-Start</span><span style="font-size:10.0pt;font-family:"Times New Roman""><o:p></o:p></span></p>
</td>
<td width="186" valign="top" style="width:139.45pt;border:solid windowtext 1.0pt;border-left:none;padding:0in 5.4pt 0in 5.4pt">
<p class="MsoNormal"><span style="font-size:10.0pt">Start of possible Return communication window
<span style="color:red">with respect the Provider’s constraints for tracking and receiving a return signal</span><o:p></o:p></span></p>
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<td width="154" valign="top" style="width:1.6in;border:solid windowtext 1.0pt;border-top:none;padding:0in 5.4pt 0in 5.4pt">
<p class="MsoNormal"><span style="font-size:10.0pt">Ret-Coms-End<o:p></o:p></span></p>
</td>
<td width="186" valign="top" style="width:139.45pt;border-top:none;border-left:none;border-bottom:solid windowtext 1.0pt;border-right:solid windowtext 1.0pt;padding:0in 5.4pt 0in 5.4pt">
<p class="MsoNormal"><span style="font-size:10.0pt">End of possible Return communication window
<span style="color:red">with respect the Provider’s constraints for tracking and receiving a return signal</span><o:p></o:p></span></p>
</td>
</tr>
<tr style="page-break-inside:avoid">
<td width="154" valign="top" style="width:1.6in;border:solid windowtext 1.0pt;border-top:none;padding:0in 5.4pt 0in 5.4pt">
<p class="MsoNormal"><span style="font-size:10.0pt">Fwd-Coms-Start<o:p></o:p></span></p>
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<td width="186" valign="top" style="width:139.45pt;border-top:none;border-left:none;border-bottom:solid windowtext 1.0pt;border-right:solid windowtext 1.0pt;padding:0in 5.4pt 0in 5.4pt">
<p class="MsoNormal"><span style="font-size:10.0pt">Start of possible Forward communication window
<span style="color:red">with respect the Provider’s constraints for tracking and transmitting a forward signal</span><o:p></o:p></span></p>
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<tr style="page-break-inside:avoid">
<td width="154" valign="top" style="width:1.6in;border:solid windowtext 1.0pt;border-top:none;padding:0in 5.4pt 0in 5.4pt">
<p class="MsoNormal"><span style="font-size:10.0pt">Fwd-Coms-End<o:p></o:p></span></p>
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<td width="186" valign="top" style="width:139.45pt;border-top:none;border-left:none;border-bottom:solid windowtext 1.0pt;border-right:solid windowtext 1.0pt;padding:0in 5.4pt 0in 5.4pt">
<p class="MsoNormal"><span style="font-size:10.0pt">End of possible Forward communication window
<span style="color:red">with respect the Provider’s constraints for tracking and transmitting a forward signal</span><o:p></o:p></span></p>
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<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">In the rare event that I didn’t quite hit the mark … we can discuss in today …<o:p></o:p></p>
<p class="MsoNormal"> <o:p></o:p></p>
<p class="MsoNormal"><span style="font-size:10.5pt;color:black">-- </span><o:p></o:p></p>
<p class="MsoNormal"><b><span style="font-size:7.5pt;font-family:Verdana;color:#008E29">Jean-Pierre Chamoun</span></b><o:p></o:p></p>
<p class="MsoNormal"><span style="font-size:7.5pt;font-family:Verdana;color:black">NASA Goddard Space Flight Center</span><o:p></o:p></p>
<p class="MsoNormal"><span style="font-size:7.5pt;font-family:Verdana;color:black">Space Network Ground System Sustainment (SGSS)</span><o:p></o:p></p>
<p class="MsoNormal"><span style="font-size:7.5pt;font-family:Verdana;color:black">Code 458 Building 12 Room N204</span><o:p></o:p></p>
<p class="MsoNormal"><span style="font-size:7.5pt;font-family:Verdana;color:black">Greenbelt, Maryland 20771</span><o:p></o:p></p>
<p class="MsoNormal"><span style="font-size:10.5pt;font-family:Consolas;color:black"> </span><o:p></o:p></p>
<p class="MsoNormal"><span style="font-size:7.5pt;font-family:Verdana;color:black">Tel: 301-286-5053</span><o:p></o:p></p>
<p class="MsoNormal"><span style="font-size:7.5pt;font-family:Verdana;color:black">email:
<a href="mailto:jean-pierre.chamoun@nasa.gov">jean-pierre.chamoun@nasa.gov</a></span><o:p></o:p></p>
<p class="MsoNormal"> <o:p></o:p></p>
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