Creat membership Creat membership
Sign in

Forgot password?

Confirm
  • Forgot password?
    Sign Up
  • Confirm
    Sign In
home > search

Now showing items 1 - 16 of 41

  • Hierarchical Slotted Wireless Random Channel Access with Power Control

    Karouit, Abdelillah   Orozco Barbosa, Luis   Ramírez-Mireles, Fernando   Haqiq, Abdelkrim  

    Download Collect
  • Hierarchical Slotted Wireless Random Channel Access with Power Control

    Karouit, Abdelillah   Orozco Barbosa, Luis   Ramirez-Mireles, Fernando   Haqiq, Abdelkrim  

    This paper introduces a hierarchical Wireless Random Access scheme based on power control where intelligence is split among the mobile users in order to drive the outcome of the system towards an efficient point. The hierarchical game is obtained by introducing a special user who plays the role of altruistic leader whereas the other users assume the role of followers. We define the power control scheme in such a way that the leader first chooses the lowest power to transmit its packets among.. available levels whereas the followers re-transmit by randomly choosing a power level picked from N - 1 higher distinct power levels. Using a 3D Markovian model, we compute the steady state of the system and derive the average system throughput and expected packet transmission delay. Our numerical results show that the proposed scheme considerably improves the global performance of the system avoiding the well known throughput collapse at high loads commonly characterizing most random channel access mechanisms.
    Download Collect
  • Spatial statistical analysis for the design of indoor particle-filter-based localization mechanisms

    Martinez-Gomez, Jesus   Martinez del Horno, Miguel   Castillo-Cara, Manuel   Brea Lujan, Victor Manuel   Orozco Barbosa, Luis   Garcia-Varea, Ismael  

    The accurate localization of end-users and resources is seen as one of the main pillars toward the successful implementation of context-based applications. While current outdoor localization mechanisms fulfill most application requirements, the design of accurate indoor localization mechanisms is still an open issue. Most research efforts are focusing on the design of mechanisms making use of the receiver signal strength indications generated by WLAN (wireless local area network) devices. However, the accuracy and robustness of such mechanisms can be severely compromised due to the random and unpredictable nature of radio channels. In this article, we develop a methodology incorporating various algorithms capable of coping with the unpredictable nature of radio channels. Following a holistic approach, we start by identifying the wireless equipment parameter setting, better meeting the implementation requirements of a robust indoor localization mechanism. We then make use of RANdom SAmple Consensus paradigm: a robust model-fitting mechanism capable of smoothing the data captured during the space survey. Using an experimental setup, we evaluate the benefits of integrating the floor plan and an ordinary Kriging interpolation algorithm in the estimation process. Our main findings show that our proposal can greatly improve the quality of the information to be used in the development of particle-filter-based indoor localization mechanisms.
    Download Collect
  • A Team Study of a Multiple-Power Wireless Random Channel Access Mechanism with Capture Effect

    Karouit, Abdelillah   Sabir, Essaid   Ramirez-Mireles, Fernando   Orozco Barbosa, Luis   Haqiq, Abdelkrim  

    We present a team analysis of a slotted random wireless channel access mechanism. Under the proposed scheme, denoted wireless random access mechanism with multiple power levels (MPL-WRA), each mobile station contends for a transmission opportunity following the principles of a slotted access mechanism incorporating a random transmitting power value selected among various available power levels. In this way, a capture effect may be produced allowing the packet to be decoded whenever the signal-to-interference-plus-noise ratio is higher than a given threshold. In order to analyze the performance and optimization of the proposed setup, we build aMarkovian model integrating the wireless access mechanism supplemented by the use of multiple power levels in an attractive and simple cross-layer fashion. We follow a team problem approach allowing us to fine tune the design parameters of the overall system configuration. Throughout an extensive numerical analysis, our main results set the basis for the social optimal system configuration of the proposed mechanism taking into account the physical constraints of using multiple power levels and the actual practical implementation of a slotted access mechanism. We end the paper with concluding remarks and future research directions including guidelines for the actual implementation of our proposal.
    Download Collect
  • On the American concept of power.by Jose Luis Orozco

    Review by: Jules R. Benjamin  

    Download Collect
  • On the American concept of power.by Jose Luis Orozco

    Review by: Jules R. Benjamin  

    Download Collect
  • El negocio de los ilegales. Ganancias para quiénby Juan Luis Orozco

    Review by: Carlos Alba Vega  

    Download Collect
  • El negocio de los ilegales. Ganancias para quiénby Juan Luis Orozco

    Review by: Carlos Alba Vega  

    Download Collect
  • Reasons of State and Reasons of Market: Theory and Practice of American Foreign Policy.by Jose Luis Orozco

    Review by: Jules R. Benjamin  

    Download Collect
  • La primera bomba hidráulica novohispana: Anotaciones al texto de Luis Chávez Orozco

    Enrique Guadian  

    Download Collect
  • La primera bomba hidráulica novohispana: Anotaciones al texto de Luis Chávez Orozco

    Enrique Guadian  

    Download Collect
  • LUIS CHAVEZ OROZCO

    Luis Rublúo  

    Download Collect
  • LUIS CHAVEZ OROZCO

    Luis Rublúo  

    Download Collect
  • Luis Chávez Orozco (1901-1966)

    J. A. M.  

    Download Collect
  • Don Luis Chávez Orozco y la historia económica de México

    Jan Bazant  

    Download Collect
  • Luis Chávez Orozco (1901-1966)

    J. A. M.  

    Download Collect
1 2 3

Contact

If you have any feedback, Please follow the official account to submit feedback.

Turn on your phone and scan

Submit Feedback