<

FONT face=Verdana>For the sake of reducing communication conflicts and channel interference furthest

this paper studies the upperbounds of channels and radios of conflictfree communication in MultiRadio MultiChannel sensor networks.We prove theoretically that when the networks communication radius NCR3×Dis(P

K

)and the Sensor Size of the networks is greater than 2K+1

the upperbound of channels

<

FONT face=Verdana>of conflictfree communication is △(CG)

in whichK is the power levels of the networks

Dis(P

K

)is the communication radius of the largest power P

K

of the networks and △(CG)is the largest degree of the conflict graph of the neworks.Based on the above upper bound

a channel assignment algorithm is proposed.Theore

tical analysis and experimental results indicate that the channel assignment algrithm this paper proposed can improve the communication efficiency of sensor networks significantly

and then increase the networks throughput.