Spectrum Sensing Using Software Defined Radio for Cognitive Radio Networks: A Survey

Abstract

Cognitive radio (CR) network has emerged as a potential solution to the under-utilization problem of the allocated radio spectrum, where spectrum sensing (SS) plays a key role to enable the coexistence between primary and secondary users. It has attracted research interests, and several works have been reported in the literature. Nevertheless, the assumptions and simplifications introduced during the modeling of the communication system often yield misleading conclusions each time relevant aspects of their implementation on a testbed are omitted. Hence, prototypes are built to study their behaviour under real-world conditions, therefore software defined radio (SDR) has emerged as an ideal vehicle to allow researchers to experiment with prototypes of these CR approaches. In this survey, we provide an overview of the latest works in CR networks related to the spectrum awareness approaches and taking into account their implementation on testbeds. These approaches are classified from a practical point of view, where a detailed review of the existing works for each category is provided. A review of the existing SDR platforms is also exposed highlighting the main components and features of current architectures employed for experimental evaluation of CR approaches. Next, the challenges to implement current spectrum awareness approaches on SDR platforms are detailed. Finally, at the light of these reviews, research challenges and open issues are identified for future research directions. INDEX TERMSCognitive radio, spectrum sensing, SDR platforms, hardware impairments.

Software-Defined UAV Networks for 6G Systems: Requirements, Opportunities, Emerging Techniques, Challenges, and Research Directions

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CycloDSP: A cyclostationary signal analysis tool for GNU Radio

“…Among SDR software platforms, GNU Radio [15] is an open-source framework, widely adopted by industrial and academic researchers, as well as amateurs and practitioners, which allows for fast prototyping of communication and signal processing solutions. SDR solutions based on GNU Radio for real-time analysis of cyclostationary signals have been presented in some papers, mainly oriented to spectrum sensing for cognitive radio applications (see [16] for a recent survey on this topic). In [17] a GNU Radio solution for realtime estimation of cyclic features in the frequency domain is proposed, with particular attention to reducing the computational burden by a two-stage approach, composed by a coarse estimation stage, followed by a fine estimation stage carried out only in close proximity to the cycle features determined in the first stage.…”

Context-Aware Lossless and Lossy Compression of Radio Frequency Signals

“…In this sense, it is important to monitor the spectrum for subsequent opportunistic transmissions. This technique is known as spectrum sensing and nowadays is usually performed with a Software Defined Radio (SDR) [ 3 ].…”