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Re: [ns] Phy/WirelessPhy set Rb_ 2*1e6 ??????? (fwd)



 i agree rb_ should be changed to bandwidth_..

-Vikram

> 
> hi Vikram,
> 
> If bandwidth has been moved to phy.{cc,h}, the files in tcl/ex and
> tcl/test should use a set bandwidth_ and not set Rb_ . What say?
> 
> btw, it seems this message of yours never got to the list becuase it
> was your first after they started sending that faq new people. I am
> inclkuding it in here.
> 
> ..vikas
> 
> Date: Mon, 25 Dec 2000 13:01:12 -0600 (CST)
> From: Vikram Kanodia <[email protected]>
> To: [email protected]
> Cc: [email protected]
> Subject: Re: [ns] Phy/WirelessPhy set Rb_ 2*1e6 ???????
> 
> 
> I agree....I have been using the original cmu extensions for mobile
> networks (implemented for ns2.1b3) and their file named
> sharedmedia.{cc,h}
> (which is equivalent to wireless-phy.{cc,h} in ns2.1b6) has the parameter
> Rb instead of bandwidth...... 
> 
> below is the snippet of their code:
> 
> as can be seen from their code everything in wireless-phy.cc is same as
> theirs but for the parameter Rb/bandwidth.....maybe someone changed this
> parameter to bandwidth in the .cc files but forgot to change in .tcl
> file...
> 
> hope this helps...but i would love to know the exact answer too :)
> 
> -Vikram
> 
> 
> SharedMedia::SharedMedia(void) : NetIf()
> {  
>   Rb = 2*1e6;		                  // 2 Mb
>   Pt = pow(10, 2.45) * 1e-3;		  // 24.5 dbm, ~ 281.8mw
>   lambda = SPEED_OF_LIGHT / (914 * 1e6);  // 914 mHz
>   L = 1.0;
>   freq = -1.0;
> 
>   /*
>    *  It sounds like 10db should be the capture threshold.
>    *
>    *  If a node is presently receiving a packet a a power level
>    *  Pa, and a packet at power level Pb arrives, the following
>    *  comparion must be made to determine whether or not capture
>    *  occurs:
>    *
>    *    10 * log(Pa) - 10 * log(Pb) > 10db
>    *
>    *  OR equivalently
>    *
>    *    Pa/Pb > 10.
>    *
>    */
>   CPThresh = 10.0;
>   CSThresh = 1.559e-11;
>   RXThresh = 3.652e-10;
> 
>   bind("CPThresh_", &CPThresh);
>   bind("CSThresh_", &CSThresh);
>   bind("RXThresh_", &RXThresh);
>   bind("Rb_", &Rb);
>   bind("Pt_", &Pt);
>   bind("freq_", &freq);
>   bind("L_", &L);
> 
>   if (freq != -1.0) 
>     { // freq was set by tcl code
>       lambda = SPEED_OF_LIGHT / freq;
>     }
> }
> 
> 
> >   I am quite puzzled by this. This variable Rb_ is set to 2Megs in a
> > bunch of example and test files (in tcl/ex and tcl/test directories) using
> > Phy/WirelessPhy set Rb_ 2*1e6. But quite astonishinlgy no such variable
> > has been defined in wireless-phy.{cc,h} or any other file for that matter.
> > It is there in phy.cc but the corresponding code is masked. Looking thru
> > wireless-phy.cc it seems that set Rb_ should be actually set bandwidth_
> >  Here is the grep output in the ns_tree
> > 
> > 
> > [vikas@indore ns-2.1b7]$ grep -r Rb_ *
> > Binary file linkstate/ls.o matches
> > Binary file linkstate/rtProtoLS.o matches
> > Binary file ns matches
> > phy.cc:// 	return hdr->size() * 8.0 /Rb_;   ----->> this is masked ! 
> > tcl/ex/PIdemo/estudy.tcl:Phy/WirelessPhy set Rb_ 2*1e6
> > tcl/ex/diffusion-prob-run.tcl:Phy/WirelessPhy set Rb_ 2*1e6
> > tcl/ex/diffusion-rate-run.tcl:Phy/WirelessPhy set Rb_ 2*1e6
> > tcl/ex/flooding-run.tcl:Phy/WirelessPhy set Rb_ 2*1e6
> > tcl/ex/grid2.tcl:Phy/WirelessPhy set Rb_ 2*1e6
> > tcl/ex/gridkeeper.tcl:Phy/WirelessPhy set Rb_ 2*1e6
> > tcl/ex/omni-run.tcl:Phy/WirelessPhy set Rb_ 2*1e6
> > tcl/ex/wired-cum-wireless-sim.tcl:Phy/WirelessPhy set Rb_ 2*1e6
> > tcl/ex/wireless-demo-csci694.tcl:Phy/WirelessPhy set Rb_ 2*1e6
> > tcl/ex/wireless-dsdv-newnode.tcl:Phy/WirelessPhy set Rb_ 2*1e6
> > tcl/ex/wireless-landmark.tcl:Phy/WirelessPhy set Rb_ 2*1e6
> > tcl/ex/wireless-mip-test.tcl:Phy/WirelessPhy set Rb_ 2*1e6
> > tcl/ex/wireless-newnode-energy.tcl:Phy/WirelessPhy set Rb_ 2*1e6
> > tcl/ex/wireless-pkt-demo.tcl:Phy/WirelessPhy set Rb_ 2*1e6
> > tcl/ex/wireless-test.tcl:Phy/WirelessPhy set Rb_ 2*1e6
> > tcl/ex/wireless.tcl:Phy/WirelessPhy set Rb_ 2*1e6
> > tcl/ex/vikas-wireless-pkt-demo.tcl:Phy/WirelessPhy set Rb_ 2*1e6
> > tcl/test/test-suite-energy.tcl:Phy/WirelessPhy set Rb_ 2*1e6
> > tcl/test/test-suite-wireless-diffusion.tcl:Phy/WirelessPhy set Rb_ 2*1e6
> > tcl/test/test-suite-wireless-gridkeeper.tcl:Phy/WirelessPhy set Rb_ 2*1e6
> > tcl/test/test-suite-wireless-lan-aodv.tcl:Phy/WirelessPhy set Rb_ 2*1e6
> > tcl/test/test-suite-wireless-lan-newnode.tcl:Phy/WirelessPhy set Rb_ 2*1e6
> > tcl/test/test-suite-wireless-lan-tora.tcl:Phy/WirelessPhy set Rb_ 2*1e6
> > tcl/test/test-suite-wireless-lan.tcl:Phy/WirelessPhy set Rb_ 2*1e6
> > tcl/test/test-suite-wireless-tdma.tcl:Phy/WirelessPhy set Rb_ 2*1e6
> > 
> > 
> > 
> > ..vikas
> > 
> > 
> 
> 
> Department of ECE, Rice University | 713 348 3786 (O)| 713 664 5650(H)
> http://www.ece.rice.edu/~kanodia 
> 
> 


Department of ECE, Rice University | 713 348 3786 (O)| 713 664 5650(H)
http://www.ece.rice.edu/~kanodia