Changeset 2805

Timestamp:

10/30/09 18:41:56 (4 weeks ago)

Author:

wark

Message:

added fig to SVN

Location:

HydroWatch/Tim/doc/ipsn10

Files:

• fig/pie_radiooff90.eps (added)
• fig/pie_radiooff90.pdf (added)
• sec_intro.tex (modified) (2 diffs)

HydroWatch/Tim/doc/ipsn10/sec_intro.tex

@@ -17 +17 @@
   \begin{tabular}{cc}
         \includegraphics[width=0.45\columnwidth]{fig/pie_lpl512} &
-        \includegraphics[width=0.5\columnwidth]{fig/dummy_piechart}\\
+        \includegraphics[width=0.55\columnwidth]{fig/pie_radiooff90}\\
          %\includegraphics[width=0.6\columnwidth]{fig/dummy_graph}\\ 
-        (a) LPL (620$\mu$A) & (b) Radio 90\% off (xxx$\mu$A) \\ 
+        (a) LPL (620$\mu$A) & (b) Radio 90\% off (87$\mu$A) \\ 
     \end{tabular}
     \caption{Piechart showing (a) Typical power breakdown for a node running LPL with 512ms sleep interval, (b) A typical power breakdown for a node scheduling the radio to be 90\% off.}
@@ -26 +26 @@
 
 An obvious way to reduce the amount of energy consumed by idle listening is to turn the radio off. Whilst the allows a large amount of energy to be redistributed to tasks such as sampling and sending (when the radio is switched on again), this approach allows incurs an additional network overhead each time the radios are turned back on in where network routing tables must be reformed. Figure~\ref{fig:energy}(b) illustrates the
-clear reduction in energy that comes about when the radio is off for long-periods (in this case 90\%), where the total consumption is reduced, in this example, to XX$\mu$A.
+clear reduction in energy that comes about when the radio is off for long-periods (in this case 90\%), where the total consumption is reduced, in this example, to 87$\mu$A.
 
  %nature of this additional cost, showing the relationship between time the radios are off and the effective energy consumed per bit of data transmitted. Once radios are off long enough, the effect of amortizing the cost of updating the network state over long periods becomes clear where in these cases the net energy cost is less than a typical low-power listening (LPL) MAC \cite{lpl04sensys}.