Data Gathering in Cognitive Radio Ad Hoc and Sensor Wireless Networks

Data gathering is a network communication task in which all of the network’s nodes send their individual messages to a distinguished sink node. In cognitive radio ad hoc and sensor wireless networks (CR-AHSWNs), unlicensed secondary users (SUs) opportunistically use channels when the licensed primary users are not using them. Therefore, the channels available to each SU vary with time and location, which makes the development of data gathering algorithms for CR-AHSWNs challenging. In this thesis, a data gathering protocol for CR-AHSWNs is proposed. The protocol consists of several distributed SU action selection and channel selection algorithms. An algorithm that can reduce the data gathering delay by selecting message forwarding SUs is also proposed. Finally, an algorithm that calculates an estimate of the successful data gathering ratio (SDGR) is proposed. The SDGR is affected by each SU’s channel availability and network collisions, and the exact value is extremely challenging to calculate