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Modern mobile communication increasingly tends to provide high speed transmission multimedia services, therefore the deployment of 4G cellular networks is expected to provide the high speed transmission multimedia services that rely on heterogeneous radio access architectures, whereby cells of different coverage and capacity coexist in the same geographical areas. In this paper, we researched the...
The information about channel statistics is sometimes not available for cognitive users a priori. The need to learn this information online creates a fundamental trade-off between exploitation and exploration. This can be formulated as a Multi-Armed Bandit (MAB) problem. In this work the channel sensing-order setting problem is studied under this scenario. It is shown that the regret of classic UCB1...
Energy efficiency and spectral efficiency are two important aspects of wireless system. In this paper, a distributed scheme of energy-efficient power control is addressed jointly with 3D-beamforming (3D-BF), named as energy-efficient 3D-beamforming (EE-3DBF). In consideration of the high complexity to deal with power control and 3D-BF simultaneously, EE-3DBF is divided into limited coordination downtilt...
Femtocell is a promising solution to improve indoor coverage and system capacity with lower transmit power and enhanced user Quality of Service in LTE network. Moreover, the integration of femtocells into cellular networks makes the inter-cell handover process more frequent and time sensitive. Because femtocell base station uses public Internet to connect with mobile core network, the legacy handover...
In Satellite Communication System, system lifetime drops drastically in energy consumption of the payload. MIMO has been done in order to take advantage of the correlation among satellites' data for increasing the capacity of channel and decreasing the transmission power. This paper studies a dual-satellite scenario based upon synchronization-deriving and gateway-processing schemes, aimed at overcoming...
Distributed antenna systems (DAS) have been studied in cellular communication systems to improve system performance and enhance system capacity. This paper studies the system outage performance of downlink DAS with beamforming at antennas ports (AP). Firstly, a composite channel including Rayleigh fading, shadowing and path loss is established. Then, the mathematical expression of system outage probability...
In this paper the nodes in a WSN are considered as the sinks dealing with different applications, which hieratically make up the network application. Ontology is used to semantically describe the application, so that nodes directly process and transmit application rather than data. Based on application semantics, a new hybrid application semantic MAC (AS-MAC) is put forward. Nodes send sub-tasks containing...
LEACH based routing protocol is a mature technology in the environment of tiny and static wireless sensor network. In most study of mobile WSN, the improved LEACH protocol only considered the mobility of member nodes. TLEACH protocol proposed in this paper implemented the establishment and maintenance of hierarchical topology in an environment that all nodes are mobile. The protocol using tree routing...
Energy efficiency (EE) is an important factor for the deployment of wireless sensor networks. Cooperative communication can help to reduce energy consumption for long distance data transmission. This paper mainly presents the optimal power allocation scheme for cooperative communication in wireless sensor networks. We formulate the EE maximization problem with power constraint, and show that this...
Maritime communication has been considered as a core issue in the marine activities. However, insufficient knowledge of radio channel characteristics over the sea limits the development of wide-band wireless communication systems for maritime applications. In order to increase understanding of the radio channel over the sea, the modeling of wireless between the UAV and vessels is studied. In this...
Network virtualization is considered as the trend of the future Internet and the solution to the growing ossification of Internet nowadays, because it is more flexible and manageable by allowing multiple heterogeneous virtual networks to coexist on a shared infrastructure. The survivability of virtual network is meaningful. In this paper, we propose a solution of survivable virtual network embedding...
In this paper, we study the performance of the coordinated distributed scheduler in IEEE 802.16 mesh mode. In the coordinated distributed scheduler, the three-way handshaking procedure, which is used for data slot scheduling, is a vital important part of the network performance. In this paper, the three-way handshaking time is newly defined from the reasonable aspect of engineering practice, arguing...
Available network bandwidth is one of the important indicators for evaluating network performance. However, the measurement accuracy of many measurement tools is lack of effective evaluation under different network environments at present, resulting in the shortage of selection basis. This study constructed a scalable network measurement platform to analyze and evaluate the main network measurement...
As High Frequency token protocol (HFTP) doesn't take the air node into consideration, a new High Frequency token protocol with reserve (HFTP-R) for multiple access (MAC) layer of the High Frequency (HF) ground-to-air IP network is put forward and its access and control process is described. HFTP-R lets air node join in the cluster organized by ground node randomly during initialization period, meanwhile...
Wireless Body Area Network (WBAN) has been considered for applications in medical, healthcare and sports fields. Although there are several protocols for wireless personal area networks, specific features and reliability requirements in WBAN bring new challenges in protocol design. An appropriate control scheme in the MAC layer can make a significant improvement in network performance. Based on traffic...
For improving the precision of the fingerprint positioning algorithm based on WIFI and decreasing the complexity of the algorithm at the same time, this paper proposed a KNN + Bayes fusion positioning algorithm based on subsection and interpolation. In the process of building fingerprint library, we use the method of linear interpolation to get the fingerprint which is in the middle of adjacent sampling...
As the single location technology is unable to meet the needs of indoor positioning accuracy and stability, we propose and design the PDR (pedestrian dead reckoning)/Wi-Fi method for indoor location in this paper. It includes the stride length calculation method based on velocity trace, gyroscope and electronic compass in combination with Wi-Fi positioning method for direction judgement, and Wi-Fi...
At outdoor environment, GPS can provide accurate location services. But at indoor environment, it can not. In order to realize accurate positioning indoor, we propose a fingerprint localization algorithm based on WiFi in this paper. In the process of our research, we will divide the indoor environment that need provide accurate location services into a certain scale of virtual grid, and tag each vertex...
In this paper, we analyze the reason why most of the NFC devices are out of application. In order to satisfy the high-tech requirements of NFC information release, we propose a transcoding mechanism between a variety of encoding messages and NFC message (NDEF). We realize the related transcoding process based on Linux OS, which can be used for main control module of NFC information release. It would...
With the continuous development of recommender systems technology, people's reliance and demand on recommender systems is increasing, while traditional recommendation models have been unable to meet this increasingly diversified demand. This paper designs a general improved model to take advantage of the additional information, especially the essential information of objective product category, other...
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