Browsing Computer Science & Communications by Issue Date

Now showing items 41-60 of 95

    • Performance Study of Multi-Path in VANETs and Their Impact on Routing Protocols 

      Wu, Jing; Wang, Yuhao (Scientific Research Publishing, 2011-07)
      Modeling complicated vehicular traffic behavior and analyzing effects on the communication performance of routing protocols taken by environmental factors have been a challenging task for the past several years. In this ...

    • Optimization of Threshold for Energy Based Spectrum Sensing Using Differential Evolution 

      Narayanan, K. Aravind; Shivaram, P. Arun; Maheshkumar, M.; Santhoshkumar, K.; Kumar, L. Sathiesh; Kumar, L. Sathiesh; Narayanankutty, K.A (Scientific Research Publishing, 2011-07)
      Interference threshold based on energy setting in cognitive radios is a non-convex optimization problem [4]. The convergence of optimization techniques like Genetic algorithm (GA) takes several iterations to fix this ...

    • Advances in Intrusion Detection System for WLAN 

      Kaur, Ravneet (Scientific Research Publishing, 2011-08)
      A wireless network is not as secure as compare the wired network because the data is transferred on air so any intruder can use hacking techniques to access that data. Indeed it is difficult to protect the data and provide ...

    • Optimal M-BCJR Turbo Decoding: The Z-MAP Algorithm 

      Ouardi, Aissa; Djebbari, Ali; Bouazza, Boubakar S. (Scientific Research Publishing, 2011-10)
      In this paper, we propose a novel idea for improvement performances of the leader M-BCJR algorithm functioning in low complexity. The basic idea consists to localize error instant possibility, and then increase the complexity ...

    • 3 - 10 GHz Ultra-Wideband Low-Noise Amplifier Using Inductive-Series Peaking Technique with Cascode Common-Source Circuit 

      Wu, Chia-Song; Lin, Tah-Yeong; Chang, Chien-Huang; Wu, Hsien-Ming (Scientific Research Publishing, 2011-10)
      The objective of this paper is to investigate a ultra-wideband (UWB) low noise amplifier (LNA) by utilizing a two-stage cascade circuit schematic associated with inductive-series peaking technique, which can improve the ...

    • A Novel Ultra-Wideband Monopole Antenna with Band-Stop Characteristic 

      Lak, Hadi J.; Ghobadi, Changiz; Nourinia, Javad (Scientific Research Publishing, 2011-10)
      In this letter, a simple monopole antenna with variable band-notched characteristic for ultra wide band (UWB) function is proposed. Two L-shaped quarter-waveguide resonators coupled to the ground plane with two shorting ...

    • Comparison of Indoor Localization Systems Based on Wireless Communications 

      Dalce, Rejane; Val, Thierry; Bossche, Adrien V. (Scientific Research Publishing, 2011-10)
      Localization using a Wireless Sensor Network (WSN) has become a field of interest for researchers in the past years. This information is expected to aid in routing, systems maintenance and health monitoring. For example, ...

    • Hybrid Amplification: An Efficient Scheme for Energy Saving in MIMO Systems 

      Poitau, Gwenael; Kouki, Ammar B. (Scientific Research Publishing, 2012-01)
      In this paper, a new amplification scheme for adaptive MIMO systems is proposed and tested. In this ‘hybrid amplification’ configuration, different amplifiers with different peak powers are used. In this way, each transmitter ...

    • Microstrip Ultra-Wideband Filter with Flexible Notch Characteristics 

      Mokhtaari, Marjan; Bornemann, Jens (Scientific Research Publishing, 2012-01)
      A microstrip ultra-wideband (UWB) filter with unique shape, compactness, simplicity of operation and flexible notch characteristics is introduced. It is based on the fundamental and harmonic characteristics of a 50 Ohm ...

    • A Comprehensive Parametric Study of Planar Inverted-F Antenna 

      Chattha, Hassan T.; Huang, Yi; Ishfaq, Muhammad K.; Boyes, Stephen J. (Scientific Research Publishing, 2012-01)
      This paper presents a comprehensive numerical and experimental study of Planar Inverted-F Antennas (PIFA) involving all the parameters which may affect the characteristics of PIFA. It is found that PIFA characteristics are ...

    • Generalized PIC Detector for Distributed STBC under Quasi-Synchronization 

      Astal, Mohammed T.; Abu-Hudrouss, Ammar M. (Scientific Research Publishing, 2012-01)
      In this paper, we propose a Generalized Parallel Interference Cancelation (G-PIC) approach for the detection of D-STBC under Quasi-Synchronization in the case of any number of relay nodes with just statistical information ...

    • Design of a Low Loss RF Mixer in Ku-Band (12 - 18 GHz) 

      Shah, Sanjeev K.; Chauhan, Rudra P.; Singh, Sanjay; Pandey, Lalit; Singh, Sandeep (Scientific Research Publishing, 2012-01)
      The goal of this paper is to design and develop low conversion loss mixers at Ku Band (12 - 18 GHz) in microstrip line configuration. The Ku-band (Kurtz-under band) is primarily used for satellite Communications, particularly ...

    • Improving Bandwidth of Yagi-Uda Arrays 

      Formato, Richard A. (Scientific Research Publishing, 2012-01)
      A novel approach for improving antenna bandwidth is described using a 6-element Yagi-Uda array as an example. The new approach applies Central Force Optimization, a deterministic metaheuristic, and Variable Z0 technology, ...

    • Intellectual CAD for Three-Tier Wide Band WDR Filters 

      Yushchenko, Alexander G.; Mamedov, Dovlet S.; Zaytsev, Denis M. (Scientific Research Publishing, 2012-01)
      The paper presents an original physical points of an intellectual CAD system designing for three-tier wide band waveguide-dielectric filters with LM modes. On the basis of formalized physical knowledge about the behavior ...

    • Interference Mitigation MAC Protocol for Cognitive Radio Networks 

      Faruk, Nasir; Ali, Maaruf; Gumel, Mohammed I. (Scientific Research Publishing, 2012-04)
      The growing demand for wireless services coupled with the limited availability of suitable electromagnetic spectrum is increasing the need for more efficient RF spectrum utilization. Spectrum allocated to TV operators can ...

    • Design of Low Power and High Speed CMOS Comparator for A/D Converter Application 

      Yewale, Shubhara; Gamad, Radheshyam (Scientific Research Publishing, 2012-04)
      This paper presents an improved method for design of CMOS comparator based on a preamplifier-latch circuit driven by a clock. Design is intended to be implemented in Sigma-delta Analog-to-Digital Converter (ADC). The main ...

    • P2P Model Based on Isolated Broadcast Domains 

      Li, Jianchun; Guo, Gongbing; Li, Jianyong; Huang, Daoying (Scientific Research Publishing, 2012-04)
      Resource location is the most important issue for Peer-to-Peer (P2P) system and flooding is the fundamental mechanism for unstructured P2P systems. Redundant messages will exponential growth with flooding scope increasing ...

    • Software Defined Radio Prototyping with Visual C++ Express and Code Composer Studio 

      Wichlund, Sverre (Scientific Research Publishing, 2012-04)
      The primary goal of this project was educational: to demonstrate Software Defined Radio based prototyping using Visual C++ Express and Code Composer Studio. More specifically an IEEE802.11a Phy [1] compliant baseband ...

    • Wireless Hybrid QoS Architecture with an Enhancement of Fair Intelligent Congestion Control 

      Zheng, Li; Hoang, Doan B.; Li, Ming (Scientific Research Publishing, 2012-07)
      More subtle and explicit QoS control mechanisms are required at the radio access level, even though the simple and scalable Differentiated Services (DiffServ) QoS control model is acceptable for the core of the network. ...

    • Throughput Maximizing Frequency and Power Scheduling for Wireless Ad-Hoc Networks in the Low-SINR Regime 

      Saberi, Nahid (Scientific Research Publishing, 2012-07)
      We study the problem of frequency and power allocation and scheduling at a time-slotted cognitive ad-hoc wireless network, where cognitive nodes share a number of frequency bands and frequency reuse is allowed. In such a ...