Tài liệu Sổ tay của các mạng không dây và điện toán di động P18 docx

... in addition guarantee that messages arrive at their destination. Our approach differs from similar algorithms studied in the lit- 393 Handbook of Wireless Networks and Mobile Computing, Edited ... [27] also studied a hybrid single path/flooding algorithm that guarantees delivery of a message. 18.3 DELAUNAY TRIANGULATIONS A common approach in serial network design is that of finding good ......

Ngày tải lên: 21/01/2014, 19:20

... one, which indicates that channels assigned to the corresponding cells must be distinct, is often referred to as a cochannel constraint. An intersite constraint of two, which codifies the requirement ... node or to dif- ferent nodes. More precisely, c i represents the constraint between nodes at graph distance i from each other. The reuse distance of G equals k + 1, the minimum graph distance...

Ngày tải lên: 15/12/2013, 05:15

... [9]. Although the impact of wireless networks can be studied along the different dimensions 289 Handbook of Wireless Networks and Mobile Computing, Edited by Ivan Stojmenovic´ Copyright © 2002 John ... Service differentiation through end-to-end rate control in low bandwidth wireless packet networks, in Proceedings of IEEE International Workshop on Mobile Multimedia Communications, San Diego,...

Ngày tải lên: 24/12/2013, 13:16

... blind flooding (flooding in a MANET is unwise according to [19]). One guideline is: the tighter the QoS requirements are, the more tickets we should issue. Each probe, on reaching any intermediate ... are discussed in [35]. 17.2.1 Proactive Protocols One representative proactive protocol is the destination-sequenced distance vector routing (DSDV) protocol. It is based on the traditional dist...

Ngày tải lên: 21/01/2014, 19:20

... Usually, the hard handoff can be further divided into two different types—intra- and intercell handoffs. The soft handoff can also be divided into two different types—multiway soft handoffs and softer ... strategies during overloading, might influence the overall performance. In the next section, we introduce different types of possible handoffs. In Section 1.3, we describe different handoff...

Ngày tải lên: 15/12/2013, 05:15

... traveled maximal distance exceeds the last reported maximal distance. The paging operation is based on the last reported cell and the maximal distance R. The system will search all R rings surrounding the ... the cells within a distance of D from the last reported cell. The distance-based strategy is dynamic, and the distance threshold D can be determined on a per-user basis depending on his/...

Ngày tải lên: 15/12/2013, 05:15

... and code division can be used in order to divide the radio spectrum. In fre- quency division, the spectrum is divided into frequency bands. In time division, the us- age of the channel is divided ... growth of radio traffic, and other fac- tors. A given radio spectrum (bandwidth) dedicated for cellular communications can be divided into a set of disjoint and noninterfering radio channels. ......

Ngày tải lên: 15/12/2013, 05:15

... Unit Disk Graphs Unit disk graphs are intersection graphs of equal sized disks in the plane. It is easy to see that given the distance model, multicoloring is equivalent to coloring for unit disk ... disk graph is the intersection graph of disks of equal diameter in the plane. They can also be described in terms of distance or proximity models, which consist of a value d Ն 0 and an embedding...

Ngày tải lên: 15/12/2013, 05:15

... fixed Algorithm complexity medium medium high high Communication complexity low medium high medium Channel utilization medium high medium high Control overhead medium high high medium introduced in Sections ... broadcast problem in mobile radio net- works, Distributed Computing 10, 3, 129–135, April 1997. 26. I. Cidon and M. Sidi, Distributed assignment algorithms for multihop packet radio n...

Ngày tải lên: 24/12/2013, 13:16

... transmitting. If the medium is found to be idle for an interval that exceeds the distributed interframe space (DIFS), the station continues with its transmission.* On the other hand (when the medium is busy), ... WLANs 155 Physical Layer Distributed Coordination Function Point Coordination Function Contention-free Contention Figure 7.6 IEEE 802.11 architecture. *To guarantee fair access to t...

Ngày tải lên: 24/12/2013, 13:16