N_BW=B_x/B_max
Where Bx is the required bandwidth of the mobile station and Bmax is the maximum bandwidth that can be provided by the base station. The normalized function for cost
N_c=1-C_x/C_TH
Where Cx is the operating cost of the network to which the candidate base station belongs to, CTH is the threshold cost, above which it is considered that the network is expensive. Compute the weight function
W_i=σ_i/(∑_(i=1)^4▒σ_i )
Where ∂i is the standard deviation of the normalization function values of all the candidate base …show more content…
RESULT
The mobile node which is multi-mode capable, initially belongs to UMTS network and starts moving towards Wi-Max and then towards Wi-Fi and stops there. We assume that the input parameters required for network selection algorithm are acquired from the network and mobile terminal.
When the mobile node moves from UMTS network towards Wi-Max network, the network selection module in the mobile terminalacquires the input parameters and normalized values of theseparameters are determined. Then network selection function valueis computed for the available networks. Due to complexityreasons, we have directly considered the normalized values of theparameters. First consider the mobile which is originally associated with UMTS network has moved towards the Wi-Max network. TheNSF computation for all the networks is as shown in Table 7.1. RSS BW D C NSF
Wi Max 0.8 0.6 0.2 0.6 0.545
Wi-Fi 0 0.6 0.5 0.8 0.384
UMTS 0.7 0.2 0.7 0.2 0.445
Weight 0.33 0.174 0.19 0.231
Table 7.1 NSF WHEN THE MOBILE IS UNDER THE COVERAGE OF Wi …show more content…
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