Cognitive DISH: Virtual Spectrum Sensing Meets Cooperation


Cognitive radio technology increases spectrum utilization by enabling secondary users to opportunistically use the spectrum when primary users are inactive. Secondary users use spectrum sensing to detect the presence of primary users in order to avoid causing harmful interference. To the best of our knowledge, all existing spectrum sensing methods are essentially physical spectrum sensing, in the sense that nodes physically tune their radio to each frequency band to sense the spectrum. In this paper, we propose a complementary approach, virtual spectrum sensing, which achieves the same goal but only senses a very small portion of the spectrum. This approach enables a Distributed Information SHaring (DISH) mechanism, where neighboring users cooperatively share spectrum usage information (obtained from virtual spectrum sensing) with users who need it in decision making. This paper presents an application of DISH to cognitive radio networks. We provide a Cognitive DISH framework which describes guidelines for cognitive radio protocol design based on virtual spectrum sensing and DISH. Under this framework, we design a protocol, VISH-I, and evaluate its performance via simulations. As the number of secondary users increases, the interference caused to primary users results in only 5% performance degradation, but the overall channel utilization is increased by 87-203%. In addition, to demonstrate that virtual sensing is complementary to physical sensing, we design a hybrid spectrum sensing protocol, VISH-II, which improves performance by 7-50% over VISH-I.

Meeting Name

6th Annual IEEE Communications Society Conference on Sensor, Mesh and Ad Hoc Communications and Networks, SECON 2009 (2009: Jun. 22-26, Rome, Italy)


Computer Science

Keywords and Phrases

Channel utilization; Cognitive radio; Cognitive radio network; Cognitive radio technologies; Distributed information sharing; Performance degradation; Protocol design; Spectrum sensing; Spectrum usage; Spectrum utilization; Virtual sensing, Frequency bands; Information dissemination; Radio; Sensor networks; Sensors, Ad hoc networks

International Standard Book Number (ISBN)


Document Type

Article - Conference proceedings

Document Version


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© 2009 Institute of Electrical and Electronics Engineers (IEEE), All rights reserved.

Publication Date

01 Jun 2009