Upper capacity bounds of MIMO wireless systems through fading channels

This paper investigates the upper capacity bounds of MIMO systems with correlation and antenna selection techniques in general fading environments. With Antenna Selection techniques, the increased hardware complexity due to multiple antennas and large number of RF chains can be reduced to a substantial amount, retaining the diversity benefits of MIMO systems. The channel Correlation also affects the capacity of MIMO fading channels. Hence, to evaluate the upper bounds of capacity through fading channels, performance of MIMO systems is exemplified under Nakagami-m and Rayleigh fading channels while considering that the channel characteristics are known at a transmitter. The obtained results give an assessment to the better understanding to the effect of antenna selection and correlation on the capacity of MIMO channels, and how they can be used in different fading environments

CSPCR: Cloud Security, Privacy and Compliance Readiness - A Trustworthy Framework

The privacy, handling, management and security of information in a cloud environment are complex and tedious tasks to achieve. With minimum investment and reduced cost of operations an organization can avail and apply the benefits of cloud computing into its business. This computing paradigm is based upon a pay as per your usage model. Moreover, security, privacy, compliance, risk management and service level agreement are critical issues in cloud computing environment. In fact, there is dire need of a model which can tackle and handle all the security and privacy issues. Therefore, we suggest a CSPCR model for evaluating the preparation of an organization to handle or to counter the threats, hazards in cloud computing environment. CSPCR discusses rules and regulations which are considered as pre-requisites in migrating or shifting to cloud computing services

On The Selection Of Qos Provisioned Routing Protocol Through Realistic Channel For Vanet

Abstract: Vehicular Ad-Hoc Network (VANET) is a new communication paradigm creating a network on wheels. Communication between the vehicles provides for various safety and comfort applications. VANET is characterized by features like number of nodes, varying topology, constrained and high speed movement of nodes. All these features make routing in VANETs a crucial issue. This paper compares popular proactive, reactive and hybrid protocols in infrastructure less environments as availability of an infrastructure is not ubiquitous. Intensive simulations are carried out using IEEE 802.11p standard in the presence of realistic propagation model. Behaviour of protocols is studied in different situations by measuring performance in terms of QoS metrics like throughput , Packet delivery ratio (PDR), routing load and end to end delay. Index Terms: QoS, VANET, AODV, OLSR, ZRP -------------------

On the Performance Analysis of Wireless Receiver in Cascaded Fading Channel

In this paper, we provide a unified analysis for wireless system over cascaded fading channels modeled either by cascaded Nakagami-m or Weibull fading models. These cascade fading models are developed by the product of independent Nakagami-m or Weibull random variables, which are not necessary identically distributed. The performance measures such as amount of fading, average bit error rate, and signal outage are computed in this analysis. We first use the Padé approximation (PA) technique to find simple to evaluate rational expressions for the moment generating function (MGF) of output signal-to-noise ratio (SNR), unlike previously derived intricate expressions in terms of MeijerG function for cascaded Nakagami-m fading channel. Rational expressions for the MGF of the cascaded Weibull random variable are also computed to provide new set of performance results. Using these rational expressions, we analyze the performance of wireless receivers under a range of representative channel fading conditions using both cascaded fading models. To verify the correctness of the proposed rational expression formulation numerical and computer simulations has been done, which shows perfect match

Performance Investigation of 1.6 Tbps Hybrid WDM-PDM-OFDM-based Free Space Optics Transmission Link

A novel ultra-high capacity free space optics (FSO) link has been developed by incorporating hybrid wavelength divison multiplexing (WDM)-polarization division multiplexing (PDM)-orthogonal frequency division multiplexing (OFDM) techniques with 16-level quadrature amplitude modulation (16-QAM) signals. Coherent detection is employed to enhance the receiver sensitivity in the presence of channel efects. The proposed link is analyzed under the impact of dynamic weather conditions viz. haze, rain, dust and fog using bit error rate, optical signal to noise ratio, error vector magnitude and maximum transmission range performance metrics. Sixteen independent DWDM channels with 0.8 nm channel spacing each carrying 100 Gbps data are successfully tranported using the proposed FSO link realizing a net data rate of 1.6 Tbps. Furthermore, we demonstrated a performance comparison of the link with contemporary works. The proposed FSO link provides a feasible and viable solution to implement ultra-high-capacity wireless transmission networks for last-mile access.A novel ultra-high capacity free space optics (FSO) link has been developed by incorporating hybrid wavelength divison multiplexing (WDM)-polarization division multiplexing (PDM)-orthogonal frequency division multiplexing (OFDM) techniques with 16-level quadrature amplitude modulation (16-QAM) signals. Coherent detection is employed to enhance the receiver sensitivity in the presence of channel efects. The proposed link is analyzed under the impact of dynamic weather conditions viz. haze, rain, dust and fog using bit error rate, optical signal to noise ratio, error vector magnitude and maximum transmission range performance metrics. Sixteen independent DWDM channels with 0.8 nm channel spacing each carrying 100 Gbps data are successfully tranported using the proposed FSO link realizing a net data rate of 1.6 Tbps. Furthermore, we demonstrated a performance comparison of the link with contemporary works. The proposed FSO link provides a feasible and viable solution to implement ultra-high-capacity wireless transmission networks for last-mile access

Investigating the performance of single- and multichannel wireless receivers in generic-K fading channels

By using versatile generic-K statistical model, a performance analysis of wireless system has been carried out through the composite fading channel scenarios. The composite fading model used here is flexible enough to represent all forms of mixed shadowed-fading channel conditions. With the aid of moment generating function (MGF) approach and Padé approximation (PA) technique, different performance measures such as outage probability and average bit error rate (ABER) have been evaluated for a variety of digital modulation formats. In contrast to previously obtained relatively complicated expressions in terms of MeijerG & Whittaker special functions, the PA technique has been used here to find tractable rational expressions for the MGF of output SNR. Using these simple rational expressions, the performance evaluations have been done for both single- and multichannel receivers under different shadowed-fading channel conditions. The numerical results are also validated through computer simulations, which show a perfect match