12.07.2015 Views

Wireless Ad Hoc and Sensor Networks

Wireless Ad Hoc and Sensor Networks

Wireless Ad Hoc and Sensor Networks

SHOW MORE
SHOW LESS
  • No tags were found...

Create successful ePaper yourself

Turn your PDF publications into a flip-book with our unique Google optimized e-Paper software.

Distributed Power Control of <strong>Wireless</strong> Cellular <strong>and</strong> Peer-to-Peer <strong>Networks</strong> 203as the vector of powers of active links <strong>and</strong>Pn() l = ( PN+ 1( l), PN+ 2(),..., l PN+ i( l), PN+ i+1 ( l), …, PN+M( l))T(5.30)the vector of powers of inactive links.Also we havePa( l+ 1) = [ R( l) + v( l)] I( l+1)(5.31)Substituting vl () =− Kxl () +η into Equation 5.31 results inPa( l+ 1) = [( I− K) R( l) + ( Kγ+ ηI)] I( l+1),(5.32)where K, P, R, η, γ are defined in Equation 5.19. Moreover, Rl () =Il ( +1)<strong>and</strong> ϕ() l = < β()l from Theorem 5.2.6.Il ()Therefore Equation 5.31 yieldsPl ()Il ()Pa( 1) = ( I− K) ϕ() 0 P( 0) + ( Kγ + ηI) ϕ( 0) I( 0)Pa( 2) = ( I− K) ϕ( 1) P() 1 + ( Kγ + ηI) ϕ()().1 I 1(5.33)(5.34)Substituting P a () 1 in P a ( 2)yieldsPa( 2) = ( I− K) 2 ϕ( 1) ϕ( 0) P( 0) + ( Kγ + ηI)[( I−K) ϕ( 1)ϕ( 0) I( 0) + ϕ( 1) I( 1)](5.35)Consequently, we can write Pa( l)asll−1P() l = ( I−K) ϕ( l−1) ϕ( l− 2) ⋯ϕ( 0) P( 0) + ( Kγ + ηI)[(I−K) ϕ( l−1)al−1ϕ( l− 2) ⋯ ϕ( 0) I( 0) + ( I−K) ϕ(l−1) ϕ( l− 2) ⋯ϕ( 1) I( 1)] + ⋯+ ϕ( l−1) I( l−1)].(5.36)From Equation 5.36, we can clearly see that the Pa( l)value converges tolim ()*Pal →D,l →∞which is a constant. (5.37)Recall, that the SIR of the ith link at the lth power update is given byRl ( + 1) = Rl ( )[ I− K]+ Kγ + η(5.38)

Hooray! Your file is uploaded and ready to be published.

Saved successfully!

Ooh no, something went wrong!