Abstract:This paper investigates the outage and diversity performance in a cognitive radio (CR) network, in which data are transmitted through amplify-and-forward (AF) protocol. A fixed CR node is selected as relay to combat fading effect. The CR user transmits or relays data when the result of cooperative spectrum sensing indicates that primary user (PU) link is free and the relay node stops performing the protocol as soon as the PU link is detected to be active. A closed-form expression of outage probability for the CR network is calculated based on which diversity order is derived. The results show that the proposed scheme suffers a loss in diversity order. To compensate for this loss, a repetition-based scheme is proposed in a delay-insensitive system at the cost of the challenge in implementation. In this case, we evaluate the outage performance and the average transmit duration and then compare them with the ones in the delay-sensitive system. An asymptotic analysis is also presented to show the outage performance advantage of using a relay over the one without using it. The numerical results presented in the paper verify our analysis.

Alert Name:
Alerting to:
Authentication email will be sent to your email address in 24 hours
Frequency:
Email Message Format:	Plain text Graphical(HTML)

Complete the form below and we will recommend the selected titles to your friends on your behalf. * Indicates a required field.
Your name*:
Your email address*:
Recipient's name*:
Recipient's email address*:
(multiple recipient's names and email addresses should be separated with semicolons)
Your comments:	I thought you would find the page(s) useful.

Your name:
Your email address:
Recipient's name:
Recipient's email address:
(multiple recipient's names and email addresses should be separated with semicolons)
Your comments:	I thought you would find this page useful.

Disclaimer: This message was sent to your friend using the "Send it to a friend" facility on the Sciencepaper Online’ WWW site, http://www.paper.edu.cn/en. The Sciencepaper Online is not responsible for the content of this email, and anything said in this email does not necessarily reflect the Sciencepaper Online's views.


	1. Outage Performance and Cooperative Diversity under Amplify and Forward Relaying in Cognitive Radio Networks
	WANG Qian,YUE Dianwu,LIU Francis
	Electrics, Communication and Autocontrol Technology 20 April 2011
	Show/Hide Abstract \| Cite this paper︱Full-text: PDF (0 B)

	Abstract:This paper investigates the outage and diversity performance in a cognitive radio (CR) network, in which data are transmitted through amplify-and-forward (AF) protocol. A fixed CR node is selected as relay to combat fading effect. The CR user transmits or relays data when the result of cooperative spectrum sensing indicates that primary user (PU) link is free and the relay node stops performing the protocol as soon as the PU link is detected to be active. A closed-form expression of outage probability for the CR network is calculated based on which diversity order is derived. The results show that the proposed scheme suffers a loss in diversity order. To compensate for this loss, a repetition-based scheme is proposed in a delay-insensitive system at the cost of the challenge in implementation. In this case, we evaluate the outage performance and the average transmit duration and then compare them with the ones in the delay-sensitive system. An asymptotic analysis is also presented to show the outage performance advantage of using a relay over the one without using it. The numerical results presented in the paper verify our analysis.
	TO cite this article:WANG Qian,YUE Dianwu,LIU Francis. Outage Performance and Cooperative Diversity under Amplify and Forward Relaying in Cognitive Radio Networks[OL].[20 April 2011] http://en.paper.edu.cn/en_releasepaper/content/4423322


	2. Performance of Cooperative Spectrum Sensing Over Fading Channels With Low SNR
	WANG Qian,YUE Dianwu,LAU Francis
	Electrics, Communication and Autocontrol Technology 20 April 2011
	Show/Hide Abstract \| Cite this paper︱Full-text: PDF (0 B)

	Abstract:In this paper, we investigate the performance of cooperative spectrum sensing over fading channels. We derive the upper-and lower-bounds of the overall false alarm probability and overall detection probability as a function of the bit error probabilities of the cognitive radio-fusion center (CR-FC) links. Given an overall false alarm probability or overall detection probability, we derive the relationships of error probabilities of the CR-FC links that should be satisfied. We also investigate the relationship between the overall detection probability and the overall false alarm probability when the SNR of the primary user signal at each CR node is small.
	TO cite this article:WANG Qian,YUE Dianwu,LAU Francis. Performance of Cooperative Spectrum Sensing Over Fading Channels With Low SNR[OL].[20 April 2011] http://en.paper.edu.cn/en_releasepaper/content/4423316

Saved Papers

Saved Papers


	3. An Optimal Cooperative Spectrum Sensing Strategy with Exponential Primary Link Traffic
	WANG Qian,YUE Dianwu,Jinhong Yuan
	Electrics, Communication and Autocontrol Technology 20 April 2011
	Show/Hide Abstract \| Cite this paper︱Full-text: PDF (0 B)

	Abstract:In this paper, we investigate the optimization of spectrum sensing performance for a cognitive radio (CR) network consisting a number of CR users and a fusion center (FC). Our objective is to develop an optimal cooperative spectrum sensing scheme so that the spectrum hole in the primary user (PU) link can be fully utilized meanwhile the existing PU service can be sufficiently protected. First, we propose a theoretical framework in the scenario of a PU link with burst nature traffic. Assuming that counting rules are utilized in the FC, we jointly consider the spectrum usage (SU) and derive the false alarm probability, the missing detection probability and the average error probability (AEP) in the maximum a posteriori (MAP) fashion, which is known to be optimal. Then, we optimize the spectrum sensing performance. By investigating the behaviors of the objective function and constraint function, we develop an efficient algorithm to search for the optimal detector threshold in each CR user and the optimal fusion rule in the FC. Finally, some numerical results are presented to verify our analysis.
	TO cite this article:WANG Qian,YUE Dianwu,Jinhong Yuan. An Optimal Cooperative Spectrum Sensing Strategy with Exponential Primary Link Traffic[OL].[20 April 2011] http://en.paper.edu.cn/en_releasepaper/content/4423313


	4. Research of post-Synchronization Mechanism based on Cross Layer Design in Wireless Sensor Network
	LIU Bin,LIANG Fengmei
	Electrics, Communication and Autocontrol Technology 10 March 2011
	Show/Hide Abstract \| Cite this paper︱Full-text: PDF (0 B)

	Abstract:This paper introduces a typical kind of time synchronization method based on cross layer consideration. The typical design of a network system mainly follows the OSI separated model. The whole design progress is always implemented without considering of the interaction with different layers. The improved post synchronization mechanism proposed in this paper presents a self correction method of estimating the crystal oscillation drift based on the cross layer consideration-the unification design of physical and media access control layer. The experiment results from wireless MCU Si1000 illustrate that the improved post synchronization using cross layer design is able to keep a stable operation of network in the way of prolong the synchronization period and reducing the cost of synchronous actions.
	TO cite this article:LIU Bin,LIANG Fengmei. Research of post-Synchronization Mechanism based on Cross Layer Design in Wireless Sensor Network[OL].[10 March 2011] http://en.paper.edu.cn/en_releasepaper/content/4415665


	5. The introduction of DVB-RCS satellite communication system
	LIU Ming,YANG Qing
	Electrics, Communication and Autocontrol Technology 04 December 2010
	Show/Hide Abstract \| Cite this paper︱Full-text: PDF (0 B)

	Abstract:VSAT is a new satellite communication system from 1980s. This system is flexible, reliable and convenient. Because of great advantages, VSAT develops rapidly during these years. However, this system can only transmit low bit-rate information, the top limit is 19.2kbit/s. With the rapid development of modern society, VSAT can no longer meet our needs. DVB is the second generation of VSAT, it can support broadband transmission. In this paper, an advanced DVB satellite communication system will be introduced, This DVB-RCS system has been deployed widely all over the world. First of all, a brief introduction on DVB-RCS will be given. At the second place, this system will be described in detail. Furthermore, the principle of DVB-RCS will be analyzed. At last, a conclusion will be given.
	TO cite this article:LIU Ming,YANG Qing. The introduction of DVB-RCS satellite communication system[OL].[ 4 December 2010] http://en.paper.edu.cn/en_releasepaper/content/4395058


	6. The design of localization algorithm based on triangle of Wireless Sensor Networks
	Zhang Jun,Shi Yong
	Electrics, Communication and Autocontrol Technology 02 December 2010
	Show/Hide Abstract \| Cite this paper︱Full-text: PDF (0 B)

	Abstract:In order to improve the dynamic node location accuracy and positioning coverage, the node localization could be applied in wireless sensor network, based on the traditional algorithm, a new node localization algorithm is proposed. In the algorithm, unknown nodes rely on the help of neighbor nodes to judge their own position, finally got his coordinates. And the simulation results compared with the traditional algorithm, and proves that the improved algorithm can greatly improve the accuracy and coverage of wireless sensor network localization.
	TO cite this article:Zhang Jun,Shi Yong. The design of localization algorithm based on triangle of Wireless Sensor Networks[OL].[ 2 December 2010] http://en.paper.edu.cn/en_releasepaper/content/4394592


	7. A novel application-oriented strategy for network selection
	Liu Wei
	Electrics, Communication and Autocontrol Technology 23 August 2010
	Show/Hide Abstract \| Cite this paper︱Full-text: PDF (0 B)

	Abstract:In recent years, network selection has been widely studied when mobile terminal can choose among multiple wireless access networks. But most schemes in current literatures are not suitable for practical usage because they all aim at choosing the best network for terminals which are probably running applications more then one type. Choosing the best network encounters two challenges: 1) How to define the best network; 2) how to allocate the best network. In this paper, we will propose a novel application-oriented network selection strategy which chooses the most suitable network for different applications running in one terminal, then chooses the best network for terminals through investigating the challenges above and considering practical usage. The design goal is to provide users the best QoS, meanwhile utilize network resource more effectively.
	TO cite this article:Liu Wei. A novel application-oriented strategy for network selection[OL].[23 August 2010] http://en.paper.edu.cn/en_releasepaper/content/4379324


	8. Joint Beamforming and Secondary User Selection in the Downlink of Cognitive Radio Networks
	Sun Zhishui,Shen Tao
	Electrics, Communication and Autocontrol Technology 28 July 2010
	Show/Hide Abstract \| Cite this paper︱Full-text: PDF (0 B)

	Abstract:In this paper, we consider a scenario that a primary network and a secondary network share the same frequency spectrum. By using subspace theory, we propose a joint beamforming and secondary user selection algorithm for the downlink of secondary network, which can produce no interference to the primary users and maximize the sum throughput simultaneously. Simulation results agree well with the theorectical analysis and also indicate that little sum rate throughput loss is induced when equal power allocation scheme is deployed.
	TO cite this article:Sun Zhishui,Shen Tao. Joint Beamforming and Secondary User Selection in the Downlink of Cognitive Radio Networks[OL].[28 July 2010] http://en.paper.edu.cn/en_releasepaper/content/4380196


	9. Implementation of EESM algorithm as Fast Link Adaptation in LTE system
	Tao Tao,Bai Zijian
	Electrics, Communication and Autocontrol Technology 21 February 2010
	Show/Hide Abstract \| Cite this paper︱Full-text: PDF (0 B)

	Abstract:This paper shows Exponential effective SNR mapping (EESM) algorithms implemented as Channel Quality Indicator (CQI) selection technique in LTE system. EESM method utilizes the post processing SINRs (Signal to Interference and Noise Ratio) to compute the effective SNR (Signal to Noise Ratio), then adjusts the transmitted information data rate (modulation scheme and channel coding rate) dynamically to match the prevailing radio channel capacity for each user. From the simulation results we can find that EESM algorithm works stable in the whole system chain and can offer around 25% throughput gain comparing to the lower bound.
	TO cite this article:Tao Tao,Bai Zijian. Implementation of EESM algorithm as Fast Link Adaptation in LTE system[OL].[21 February 2010] http://en.paper.edu.cn/en_releasepaper/content/40227


	10. Research on the improvement of multicast Ad Hoc On-demand Distance Vector in MANETS
	Weiliang Li
	Electrics, Communication and Autocontrol Technology 26 January 2010
	Show/Hide Abstract \| Cite this paper︱Full-text: PDF (0 B)

	Abstract:Tree-based multicast routing provides fast and most efficient way of routing establishment for the communications of mobile nodes in wireless Ad Hoc networks. MAODV (Multicast Ad Hoc On-demand Distance Vector) is one commonly known tree-based multicast routing protocol, which has minimal control overhead and route acquisition latency. This paper presents a way to improve the throughput of the system and reduce the number of mobile nodes participating in multicast routing algorithms, which will significantly reduce the routing-related control overhead. A systematic performance evaluation is done by performing certain simulations under NS-2.The applicability of these protocols to diverse situation are also studied and discussed.
	TO cite this article:Weiliang Li. Research on the improvement of multicast Ad Hoc On-demand Distance Vector in MANETS[OL].[26 January 2010] http://en.paper.edu.cn/en_releasepaper/content/39482

	Check out RSS, or use RSS reader to subscribe this item