[ns] Help with Radio states of 802.15.4 implementation (Ankur Garg)

[ankur garg]

What will happen if i remove this code and recompile will it work ..from
your reply i got that this condition will actually never reached. Please Do
reply.

On Fri, Jun 13, 2008 at 11:42 PM, Stefano Busanelli <busajd at gmail.com>
wrote:

> Hi,
> the parameter aTurnaroundtime of the IEEE 802.15.4 standard (both 2003
> and 2006 versions) fix the maximum transition time between RX and TX
> states (and viceversa),
> and the ns-2 model uses that value. It is a worst case assumption but
> is realistic.
>
>
> http://standards.ieee.org/getieee802/download/802.15.4-2006.pdf
>
> 2008/6/13 ankur garg <ankurgarg.ism at gmail.com>:
> >
> > Hi!,
> >
> > I am working on the 802.15.4. I am tweaking up things to implement a new
> > protocol. Can any body tell me why a transition of radio state TX_ON to
> > RX_ON is not done immediately. this has been done  using a turn
> > _around_state with a delay of turn_around and two times a confirmation
> goes:
> >
> > 1. from this plme_set_trx_state_confirmation with state as p_SUCCESS
> > 2. when the TRXhandler is called it confirms the state as TX_ON/RX_ON.
> >
> > Is this because of RFC of 802.15.4 or just done for simulation or a
> > limitation of radio that it takes a turnaorund time for switching.
> >
> > I am also posting here the code section from file wpan/phy802_15_4.cc
> > --------------------------------------------------
> > CODE
> > -------------------------------------------------
> >        {
> >            t_status = p_SUCCESS;
> >            if (((state == p_RX_ON)&&(trx_state == p_TX_ON))
> >              ||((state == p_TX_ON)&&(trx_state == p_RX_ON)))
> >            {
> >                trx_state_turnaround = state;
> >                delay = true;
> >            }
> >            else
> >                trx_state = state;
> >        }
> >        //we need to delay <aTurnaroundTime> symbols if Tx2Rx or Rx2Tx
> >        if (delay)
> >        {
> >            trx_state = p_TRX_OFF;    //should be disabled immediately
> > (further transmission/reception will not succeed)
> >            TRXH.start(aTurnaroundTime/getRate('s'));
> >        }
> >        else
> >            mac->PLME_SET_TRX_STATE_confirm(t_status);
> >
>