Seamless Handover decision algorithms and optimization in heterogeneous wireless networks.pdf

1、Current and future generation of Internet is expected to consist of different Wireless networks with diverse performances.Considering the complementary Characteristics of 3G and WLAN,this combination can achieve anywhere

2、,anytime Internet access and brings benefits to both end users and service providers.This Therefore raises the question of how to handle efficient handoff decision support Between the various wireless access technologies

3、 and networks.Thus an efficient Vertical handoff algorithm is needed to make intelligent handoff decisions.The design Issue here is to determine the conditions under which vertical handoff should be Performed.Definitely

4、because no single technology can provide ubiquitous coverage And continuously high quality ‐of ‐service(QoS),mobile terminals will have to roam Among various access technologies to maintain network connectivity and user

5、Satisfaction.Besides Inter ‐radio access technology handover decision making has a Greater impact on both system performance and user experience.Thus involving higher Signaling complexity,more radio resource allocation d

6、ifficulty,and higher system Management complexity on both source and target networks.Premature or incorrect Inter ‐technology handover decisions will likely have more severe consequences.
　　 This thesis therefore,pre

7、sents an integrated seamless handoff decision algorithm based On Markov Decision Process(MDP)that couples a cellular network(2.5G/3G)with a Wireless Local Area network(802.11b).The aim is to determine an optimal policy w

8、hich Maximizes the total expected reward per connection.For this we use the policy iteration algorithm.The performance is then compared with other vertical handoff algorithms Namely;MEW(Multiplicative Exponent Weighting)

9、,SAW(Simple Additive Weighting),TOPSIS(Technique for Order Preference by Similarity to Ideal Solution),and GRA(Grey Relational Analysis).Our analysis shows that our integrated MDP –based Vertical handoff algorithm shows

10、a better performance than others.Hence we seek to Make the following contributions:
　　 A survey and a comparative study on current decision selection algorithms in Heterogeneous networks.
　　 We formulate an integ