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Mike Morgan. Wireless Network Optimisation. Categories of Wireless Device. Fixed Physically fixed in position e.g. Antenna mounted on tower or rooftop Commonly used for broadband communications Portable Stays in place while being used, but can be picked up and moved to another location
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Mike Morgan Wireless Network Optimisation
Categories of Wireless Device • Fixed • Physically fixed in position e.g. Antenna mounted on tower or rooftop • Commonly used for broadband communications • Portable • Stays in place while being used, but can be picked up and moved to another location • Mobile • In motion during use
Fixed Wireless Network Types • Point to Point • Bus Topology • Point to Multipoint • Star Topology • Consecutive Point • Ring topology: some redundancy • Hamiltonian Cycle • Mesh • Mesh Topology: better redundancy • Design problem is very complex
Mesh Networks • How many different ways can these nine devices be connected? • Which one is the best?
Design of Mesh Networks • Some devices perform the task of 'relaying' data on behalf of others. • The equipment needed for relay devices is normally far more expensive than for ordinary terminals. • Two design goals: • The number of relays used ought to be kept to a minimum. • The network should provide adequate redundancy and be able to handle traffic demands.
Heuristics • It is not possible to evaluate all possible mesh structures within a useful time frame • A smaller subset of possible network designs must be evaluated. Optimal answers cannot be guaranteed. • How might it be possible to select good designs for evaluation among so many alternatives?
Construction methods • Greedy construction searches build the network component by component. • Start with nothing and add relays in until all objectives are satisfied. • Start with a maximum number of relays and drop as many as possible without violating constraints • These searches can be adapted using iteration, random factors and memory based techniques.
Perturbation Methods • Make minor alterations to a current solution in the hope of finding an improvement. • Also may be adapted using random factors and memory. • Useful as a means of improving already promising solutions