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COEXISTENCE OF PRIMARY USERS AND SECONDARY USERS UNDER INTERFERENCE TEMPERATURE AND SINR LIMIT
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作者 Wu Yingxiao Yang Zhen 《Journal of Electronics(China)》 2009年第3期303-311,共9页
Spectrum sharing offers the opportunity for promising efficiency gains, and it will be a valuable tool in the era of future radios.To address this issue, we develop a multi-user cognitive radio sharing network based o... Spectrum sharing offers the opportunity for promising efficiency gains, and it will be a valuable tool in the era of future radios.To address this issue, we develop a multi-user cognitive radio sharing network based on opportunistic spectrum access and propose a new spectrum sharing strategy.The objective of our interest is to obtain the number of secondary users who can coexist peacefully with primary users to improve the utility of licensed spectrum, at the same time maximize the total goodput under the interference temperature and SINR constraints.Through analysis and simulation, the new strategy of spectrum sharing does improve the goodput performance as well as guarantee the Quality of Service(QoS) of primary and secondary users. 展开更多
关键词 Spectrum sharing COEXISTENCE interference temperature limit SINR limit Opportunistic spectrum access
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A new protocol for concurrently allocating licensed spectrum to underlay cognitive users
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作者 Sabyasachi Chatterjee Prabir Banerjee Mita Nasipuri 《Digital Communications and Networks》 SCIE 2018年第3期200-208,共9页
Cognitive radio technology makes efficient use of the valuable radio frequency spectrum in a non-interfering manner to solve the problem of spectrum scarcity. This paper aims to design a scheme for the concurrent use ... Cognitive radio technology makes efficient use of the valuable radio frequency spectrum in a non-interfering manner to solve the problem of spectrum scarcity. This paper aims to design a scheme for the concurrent use of licensed frequencies by Underlay Cognitive Users (UCUs). We develop a new receiver-initiated Medium Access Control (MAC) protocol to facilitate the selections of alternative reliable carrier frequencies. A circuit is designed to establish reliable carrier selections based on the Received Signal Strength Indicator (RSSI) at the receiving end. Based on both packet-level simulations and various performance parameters, a comparison is carried out among conventional techniques, including the Multiple Access with Collision Avoidance (MACA) and MACA by invitation(MACA-BI) techniques, and our scheme. The simulated results demonstrate that when conventional techniques are used, the system overhead time increases from 0.5 s on the first attempt to 16.5 s on the sixth attempt. In the proposed scheme under the same failure condition, overhead time varies from 0.5 s to 2 s. This improvement is due to the complete elimination of the exponential waiting time that occurs during failed transmissions. An average efficiency of 60% is achieved with our scheme while only 43% and 34% average efficiencies are achieved with the MACA and MACA-BI techniques, respectively. The throughput performance of our scheme on the fourth attempt is 7 Mbps, whereas for the MACA and MACA-BI protocols, it is 1.9 Mbps and 2.2 Mbps respectively. 展开更多
关键词 Exponential back-off time interference temperature limit Medium-access control PROTOCOL Received signal strength indicator Underlay cognitive user
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