Understanding Radio Irregularity in Wireless Networks

Joint work with Patrick Stüdi, Fabian Kuhn and Gustavo Alonso

Content

Network Model Connectivity Edge Length Interference

Network Model (1)Wireless network: network of computers (nodes) withouta fixed infrastructure, nodes communicate via wireless links

Network Model Connectivity Edge Length Interference

Network Model (2)

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Network Model Connectivity Edge Length Interference

Network Model (3)

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Network Model Connectivity Edge Length Interference

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Network Model

Connectivity Edge Length Interference

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Connectivity & Node Degree

Network Model

Connectivity Edge Length Interference

[Stüdi, Chinellato, Alonso 05][Bettstetter, Hartmann 05]

Adaptive Power Assignment

Irregular radio propagation improves connectivity.

Similar phenomena known from percolation theory

[Booth, Bruck, Cook, Franceschetti 03]

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[Jonasson 01], [Roy, Tanemura 02]

Network Model

Connectivity Edge Length Interference

Distance Distribution

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[Trott 04]

Network Model Connectivity

Edge Length Interference

Edge length distributionEdge power distributionunder channel randomness

Edge Length Distribution

Irregular radio propagation increases the average edge length.

Network Model Connectivity

Edge Length Interference

Interference- Number of interferers: number of nodes that must

not send concurrently to a given network link

- Studied interference under log-normal shadowing and a power assignment that keeps the expected cumulated noise constant

Log-normal shadowing reduces the number of interferers.

Radio irregularity from log-normal shadowing is beneficial for both connectivity and interference.

A comparable unit disk model is a worst case scenario for connectivity and interference.

Network Model Connectivity Edge Length

Interference