On OFDM-based cognitive radio link adaptation using cross entropy approach

Today's wireless networks are characterized by fixed spectrum assignment policy. The spectral scarcity and the inefficiency in the spectrum usage necessitate new communication paradigms to exploit the existing wireless spectrum, opportunistically. Software Defined Radio (SDR) and Cognitive Radio (CR) are the very paradigms for wireless communication, in which either a network or a wireless node reconfigures its transmission or reception parameters to communicate efficiently, avoiding interference with licensed or unlicensed users. CR adapts itself to the newer environment on the basis of its intelligent sensing and captures the best available spectrum to meet user communication requirements. When the radio link features are extended to the network layer, the cognitive radios form the cognitive radio network. This chapter is focused on software defined radio, its architecture, its limitations, evolution to cognitive radio network, architecture of the CR, and its relevance in wireless and mobile ad-hoc networks.

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Iterative Receiver Signal Processing for Joint Mitigation of Transmitter and Receiver Phase Noise in OFDM-Based Cognitive Radio Link

Proceedings of the 7th International Conference on Cognitive Radio Oriented Wireless Networks ◽

10.4108/icst.crowncom.2012.249438 ◽

2012 ◽

Cited By ~ 3

Author(s):

Ville Syrjaelae ◽

Mikko Valkama

Keyword(s):

Signal Processing ◽

Cognitive Radio ◽

Phase Noise ◽

Radio Link ◽

Iterative Receiver

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An urban expressway forwarding scheme for cognitive Internet of vehicles

International Journal of Distributed Sensor Networks ◽

10.1177/1550147720912947 ◽

2020 ◽

Vol 16 (3) ◽

pp. 155014772091294

Author(s):

Jing Wang ◽

Huyin Zhang ◽

Sheng Hao ◽

Chuhao Fu

Keyword(s):

Cognitive Radio ◽

Traffic Safety ◽

Smart Cities ◽

Radio Spectrum ◽

Base Stations ◽

Radio Link ◽

Integer Optimization ◽

Internet Of Vehicles ◽

Urban Expressway ◽

Channel Availability

The Internet of vehicles is an essential component for building smart cities that can improve traffic safety and provide multimedia entertainment services. The cognitive radio–enabled Internet of vehicles was proposed to resolve the conflict between the increasing demand of Internet of vehicles applications and the limited spectrum resources. The multi-hop transmission is one of the most important issues in cognitive radio–enabled Internet of vehicles networks. Nevertheless, most existing forwarding solutions designed for the cognitive radio–enabled Internet of vehicles did not consider the urban expressway scenario, where primary base stations are densely installed with small coverage areas. In this case, it is difficult to ensure that the sender and the receiver of the same cognitive radio link have similar channel availability statistics, which makes cognitive radio links more likely to be interrupted. To address this challenge, we develop a multi-hop forwarding scheme to minimize the end-to-end delay for such networks. We first formulate the delay minimization problem as a non-linear integer optimization problem. Then, we propose an approach to select the relay candidates by jointly considering the high mobility of vehicles and the unique cognitive radio spectrum usage distributions in urban expressway scenarios. Finally, we propose the low-latency forwarding strategies by considering the channel availability and the delay cost of different situations of relay candidates. Simulations show the advantages of our proposed scheme, compared with state-of-art methods.

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