# Differences

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+
+===== HF Radio Power Calcs =====
+
+EBR = Effective Bit Rate (Bytes/Second)\\
+SS = Sample Size (Bytes/Sample)\\
+PT = Preamble Time (Seconds)\\
+SR = Sample Rate (Samples/Second)\\
+GD = Group Duration (Seconds, how long are you grouping)\\
+GS = Group Size (Samples/Group) = <m>SR * GD</m>\\
+<m>SP_{n}</m> = Sample Power for Flight Interval n (seconds)\\
+<m>TS_{n}</m> = Number of Transmissions per Second in Flight Interval n\\
+TP = Power Used by Transmitter during TX (mW)\\
+PB = Total Power Budget Required (mW-S)
+
+<m>SP_{n} = (SS/EBR) * (GS) + (PT)</m>
+
+<m>TS_{n} = {{Interval Duration}*{SR}}/{Group Size}</m>
+
+<m>PB = TP * sum{n}{}{SP_{n} * TS_{n}}</m>
+
+==== Example 1 ====
+
+Two Flight Intervals: Over the US, Not Over the US.\\
+Total Flight Time = 72 Hours\\
+
+For Flight Interval 1, Over the US:\\
+
+Over the US is represented by a single large group.  Group Size = <m>{Samples/Minute} * {Minutes Over the US}</m>
+
+For this example, we will spend 330 Minutes over the US, 1 Sample / Minute * 5.5 hours = 330
+
+EBR = 12 Bytes / Second\\
+SS = 50 Bytes\\
+PT = 30 Seconds\\
+GS = 330 Samples\\
+
+<m>SP_{1} = (50/12) * (330) + (30) = 1405 Seconds</m>
+
+<m>TS_{1} = {{330 minutes}*{{1 Sample}/{Minute}}}/{330} = 1</m>
+
+For Flight Interval 2, Not Over the US:\\
+
+For this example, we will group for 15 minutes at a time. For this example, we spend 3990 minutes NOT over the US.
+
+EBR = 12 Bytes/ Second\\
+SS = 50 Bytes\\
+PT = 30 Seconds\\
+GS = (1 Sample/Minute) * (15 minutes) = 15 Samples\\
+
+<m>SP_{2} = (50/12) * (15) + (30) = 92.5 Seconds</m>
+
+<m>TS_{2} = {{3990 minutes}*{{1 Sample}/{Minute}}}/{15} = 266</m>
+
+Putting it all together:
+
+TP = 2000mW
+
+<m>PB = 2000mW * {{1405 Seconds}*{1} + {92.5 Seconds}*{266}} = 52020000 mW-S = 14450 mW-H</m>
+
+Assuming each battery cell delivers 1 volt at high current draw, and 1500 mA-H: 1500 mW-H / Cell = 10 Cells 