IEEE has set up in October 2004 the IEEE802.22 Working Group—Wireless Regional Area Network (WRAN) Task Force to work out air interface standard based on Cognitive Radio (CR) technologies. The standard includes Physi...IEEE has set up in October 2004 the IEEE802.22 Working Group—Wireless Regional Area Network (WRAN) Task Force to work out air interface standard based on Cognitive Radio (CR) technologies. The standard includes Physical Layer (PHY) and Media Access Control (MAC),to use the already allocated fallow spectrums to broadcast TV in a non-interference way. The WRAN employs CR technologies to sense and estimate the television frequencies and use the technologies of dynamic spectrum management to find and then allocate idle spectrums. The CR technologies are representing one of the major trends for future wireless communications. This article on WRANs and CR technologies will be divided into two issues. In this issue,WRANs and IEEE 802.22,CR technologies are introduced. And the second part in the next issue will analyze the applications of CR technologies.展开更多
IEEE has set up in October 2004 the IEEE802.22 Working Group-Wireless Regional Area Network (WRAN) Task Force to work out air interface standard based on Cognitive Radio (CR) technologies. The standard includes Physic...IEEE has set up in October 2004 the IEEE802.22 Working Group-Wireless Regional Area Network (WRAN) Task Force to work out air interface standard based on Cognitive Radio (CR) technologies. The standard includes Physical Layer (PHY) and Media Access Control (MAC), utilizig the vacant spectrum bands already allocated to broadcast TV without interference.. The WRAN employs CR technologies to sense and estimate the television signals and use the technologies of dynamic spectrum management to find and then allocate vacant spectrums. The CR technologies are representing one of the major trends for future wireless communications. This article on WRANs and CR technologies will be divided into two issues. In this issue, WRANs and IEEE 802.22, CR technologies are introduced. And the second part in the next issue will analyze the applications of CR technologies.展开更多
The IEEE 802.22 standard based on wireless Cognitive Radio (CR) is an optimal solution to resolve the inefficient spectrum utility problem. In this paper, we focus on the spectrum allocation in IEEE 802.22 mesh networ...The IEEE 802.22 standard based on wireless Cognitive Radio (CR) is an optimal solution to resolve the inefficient spectrum utility problem. In this paper, we focus on the spectrum allocation in IEEE 802.22 mesh networks and propose a new graph-theory algorithm. The algorithm aims at two objectives: one is the sum of the allocated channel bandwidth is maximum, and the other is the number of users can be active simultaneity is maximum. In this proposed algorithm, the topology of network was modeled as a general graph and could be transformed into a weighted complete bipartite-graph by three processes. The simulations show that the presented algorithm can improve the performance of spectrum allocation.展开更多
文摘IEEE has set up in October 2004 the IEEE802.22 Working Group—Wireless Regional Area Network (WRAN) Task Force to work out air interface standard based on Cognitive Radio (CR) technologies. The standard includes Physical Layer (PHY) and Media Access Control (MAC),to use the already allocated fallow spectrums to broadcast TV in a non-interference way. The WRAN employs CR technologies to sense and estimate the television frequencies and use the technologies of dynamic spectrum management to find and then allocate idle spectrums. The CR technologies are representing one of the major trends for future wireless communications. This article on WRANs and CR technologies will be divided into two issues. In this issue,WRANs and IEEE 802.22,CR technologies are introduced. And the second part in the next issue will analyze the applications of CR technologies.
基金Key Project of Chinese Ministry of Education(No.206055)
文摘IEEE has set up in October 2004 the IEEE802.22 Working Group-Wireless Regional Area Network (WRAN) Task Force to work out air interface standard based on Cognitive Radio (CR) technologies. The standard includes Physical Layer (PHY) and Media Access Control (MAC), utilizig the vacant spectrum bands already allocated to broadcast TV without interference.. The WRAN employs CR technologies to sense and estimate the television signals and use the technologies of dynamic spectrum management to find and then allocate vacant spectrums. The CR technologies are representing one of the major trends for future wireless communications. This article on WRANs and CR technologies will be divided into two issues. In this issue, WRANs and IEEE 802.22, CR technologies are introduced. And the second part in the next issue will analyze the applications of CR technologies.
文摘The IEEE 802.22 standard based on wireless Cognitive Radio (CR) is an optimal solution to resolve the inefficient spectrum utility problem. In this paper, we focus on the spectrum allocation in IEEE 802.22 mesh networks and propose a new graph-theory algorithm. The algorithm aims at two objectives: one is the sum of the allocated channel bandwidth is maximum, and the other is the number of users can be active simultaneity is maximum. In this proposed algorithm, the topology of network was modeled as a general graph and could be transformed into a weighted complete bipartite-graph by three processes. The simulations show that the presented algorithm can improve the performance of spectrum allocation.
