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In this study, we compare the cooperative MAC protocols, the routing protocols, and the transport protocols, all of which support cooperative communications. Numerical results and comparisons of three cooperative MAC protocols with reactive helper node selection mechanisms are presented. Research trends, as well as the advantages and disadvantages of related research, on cross-layer cooperative MAC...
Providing natural hand interaction between a virtual object and a user on Augmented Reality is a major issue to manipulate a rendered object in a convenient way. Conventional 2D image-based recognition and interaction technique in AR has a limitation to perform a natural interaction between the user and the virtual object. In this paper, we present a stereo-vision based natural 3D hand interaction...
Radar systems, based on Multistatic radar concept attracted a substantial attention in the recent years. The paper proposes system geometry for S-band Multistatic radar. This technique is used for detecting and tracking the small cross section area and stealthy aircrafts. The proposed geometrical structures are studied with different radars spacing to extend the detection coverage over the Monostatic...
The growing global Internet traffic will inevitably lead to a serious upgrade of the current optical networks' capacity. Instead of upgrading the data rate of each wavelength in every fibre link across the entire optical WDM network infrastructure, it is more efficient and cost-effective to support different data rates within one fibre link (e.g., 10, 40 and 100 Gbps). This is called optical network...
Single Carrier Frequency Division Multiple Access (SC-FDMA) has been selected for use in the Long Term Evolution (LTE) uplink due to its lower Peak-to-Average Power Ratio (PAPR) relative to OFDMA The resultant lower PAPR results in fewer excursions into the amplifier's nonlinear region, where signal distortion can occur and results in degraded bit error rate (BER). The SC-FDMA scheme normally applies...
In the last decades, many kinds of task execution models such as grid and cloud computing have been developed. In such distributed systems, each task is processed by respective processor in multicored computers e.g., household PCs which we can easily harness in recent years. If there is one policy to automatically decide the "best" combination and the number of processors (and computers),...
The development and miniaturization of electronic devices and components is pushing the system devices and their interconnecting interfaces to become even smaller. Thus, reducing the size of receiver (Rx) and transmitter (Tx) chips plays an plays an important role in designing a small-size optical modules utilized in o/e and e/o converters. Therefore, designing a small-area optical Rx may require...
Fiber Raman amplifiers in ultra wideband wavelength division multiplexing (UW-WDM) systems have recently received much more attention because of their greatly extended bandwidth and distributed amplification with the installed fiber as gain medium. It has been shown that the bandwidth of the amplifier can be further increased and gain spectrum can be tailored by using pumping with multiple wavelengths...
In mobile environment, the performance of OFDM mobile receivers is degraded severely because of Inter-Carrier-Interference (ICI) caused by Doppler Spread. So ICI canceller is an important task for designers of mobile OFDM receivers. [1] and [2] proposed an efficient method to reduce ICI. The main idea of this method is to linearly approximate time varying channel within one OFDM symbol. Then a large...
The time synchronization is very important for network testing that is at a long distance. For time synchronization, two different network testing apparatuses uses a network time protocol (NTP) or a geographic position system (GPS). For using GPS with less timing error, an expensive GPS antenna needs to be installed outside the door. NTP is through the network. The network itself causes a time delay...
The system that uses network coding is highly susceptible to pollution attacks, where a malicious node may pollute a small number of packets with the purpose of preventing the recipient nodes from reconstructing the original messages properly. Some schemes that use Message Authentication Code (MAC) have been proposed for resisting this attack. However, these schemes could be broken with probability...
Human life is rapidly changing around the world in terms of smart phones as the number of users is increasing in a surprising rate and the recent development of remarkable performances. And, there is wide range of smart phone services available based on the location information. However, levels of location based services currently provided are not satisfactory due to the GPS error rate. Though there...
The problem of minimizing the number of coding nodes is caused by network coding overhead and is proved to be NP-hard. To resolve this issue, this paper proposes Centrality-based Network Coding Node Selection (CNCNS) that is the heuristic and distributed mechanism to minimize the number of network coding (NC) nodes without compromising the achievable network throughput. CNCNS iteratively analyses...
As smart device hardware and software technologies have advanced, performance of devices has improved and their types and categories have diversified. In addition, as smart devices have become popular, the number of multi-devices held by a single person has increased. Following this trend, data production and management through multi-devices of a single user have increased, and various data sharing...
Cloud becomes increasingly important currently, and media services, which usually have multiple steps and complexity computing requirement, are applied in it. Although this scheduling topic has been investigated a lot, most of works focus on balancing jobs or decreasing the execution time of one job. For large scale paralleling media services, the job request usually contains a series tasks, and how...
In the paper, the constellation composed of MEO (Medium Earth Orbit) satellite is put as a researching scenario, the relative measurement and data transmission task which are finished by slow changing ISLs are put as a researching object, the integrated management of relative measurement and data transmission task inside the satellite network is put as a studying objective. Firstly, the characteristic...
Surveillance video streams monitoring is an important task that the surveillance operators usually carry out. The distribution of video surveillance facilities over multiple premises and the mobility of surveillance users requires that they are able to view surveillance video seamlessly from their mobile devices. In order to satisfy this requirement, we propose a cloud-based IPTV (Internet Protocol...
With the increasing growth of multimedia communication and web services technologies, a number of collaborative media services are being built for ubiquitous user access. However, there exist so many devices with similar functionality but with heterogeneous QoS capability. In order to have suitable services according to desired QoS, services need to be selected. This article presents the corresponding...
The future Internet will be evolved to mobile-oriented environments, and thus the mobility support is a key issue in the design of future Internet. This paper proposes a distributed identifier-locator mapping system (DMS) for the future mobile-oriented Internet environment, which is designed on the identifier-locator (ID-LOC) separation principle. The proposed DMS scheme is implemented over Linux...
The promising projects of satellite swarm have been studied by scientists from NASA, ESA and other institutes around the world. With a massive number of pico-class, low-power and low-weight space-crafts like pico-satellites, nano-satellites, Swarm can exploring outer space environment or taking other tasks that are hard to be fulfilled by common satellites. The other merit of using swarm than common...
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