Hello Vikram, your problem sounds like the hidden station problem in WLAN. There is a soution described in IEEE 802.11 called RTS/CTS. Some basic information about this mechanism is delivered by wikipedia (http://en.wikipedia.org/wiki/IEEE_802.11_RTS/CTS). But introducing this mechanism will introduce more signalling in your network and decrease your availiable bandwidth, if it is implementable in an efficient way at all...
Hope this will help you a bit... Regards, Henning -------- Original-Nachricht -------- > Datum: Wed, 28 Oct 2009 10:52:48 +0530 > Von: Vikram vik76 <[email protected]> > An: tinyos-help <[email protected]> > Betreff: [Tinyos-help] Nodes with different RF power > Hello everybody, > I want to work for a scenario where in the WSN network (comprising of > micaz > motes), one of the node say node 'A' (base-station connected to PC) needs > to > do a broadcast to all the other nodes. The remaining nodes communicate > via > multi-hop communication. To achieve this, I want node 'A' to have a very > high transmission power whereas for the remaining nodes low transmission > power. I use the CC2420_DEF_RFPOWER variable to set the RF power. say > for > node 'A' this value is 31 and for the remaining nodes it is 2. > Now, the problem is since, nodes have different transmission power, if > there > is a multi-hop communication going on between the other nodes, then node > 'A' > should not do the broadcast as this may lead to collisions. node 'A's > broadcast is supposed to reach all other nodes without the packets being > corrupted. > How do I achieve this? Is there a way wherein I can increasing the > carrier > sensing capabilities of node 'A' so that node 'A' can sense the multi-hop > communication that is going on between other nodes? Please suggest. > > Thanks > Vikram -- Jetzt kostenlos herunterladen: Internet Explorer 8 und Mozilla Firefox 3.5 - sicherer, schneller und einfacher! http://portal.gmx.net/de/go/chbrowser _______________________________________________ Tinyos-help mailing list [email protected] https://www.millennium.berkeley.edu/cgi-bin/mailman/listinfo/tinyos-help
