In modern wireless communication systems, Doppler frequency reduction is employed for efficient transmission of data in noisy environments. Achieving a very less bit error rate (BER) has been the major task in the orthogonal frequency division multiplexing (OFDM), which is a popular multicarrier modulation technique in IEEE 802.11a wireless systems and is currently being used in the IEEE 802.16...

Violations of spatiotemporal continuity disrupt performance in many tasks involving attention and working memory, but experiments on this topic have been limited to the study of moment-by-moment on-line perception, typically assessed by passive monitoring tasks. We tested whether persisting object representations also serve as underlying units of longer-term memory and active spatial navigation...

In this paper, the wireless system consisting of macrodiversity selection combining (SC) receiver and two microdiversity SC receivers under the influence of small scale fading and large scale fading, as well as co-channel interference is observed. Small scale fading has Weibull distribution. Correlated large scale fading is described by Gamma distribution. Co-channel interference is disturbed b...

Most of the traffic in today’s network uses the Transmission Control Protocol (TCP) as the transport layer protocol for reliable end-to-end packet delivery. However, TCP considers packet loss to be the result of network congestion which makes it unsuitable for mobile wireless communication, where sporadic and temporary packet losses are usual due to fading, shadowing, hand-off and other radio e...

Abstract Recently, the frequency-domain equalization (FDE) has been attracting much attention since it is an effective equalization technique for direct-sequence code division multiple access (DS-CDMA) signal transmission in a frequency-selective fading channel. In practical systems, the square-root Nyquist transmit and receive filters are used for the bandwidth limitation of the transmitted si...

abstract creating suitable classrooms that can meet the educational needs of mentally-retarded students is vitally important. the present study explores the effect of three physical characteristics of classroom environment on the creativity of educable mentally-retarded children: window view, window size, and classroom size. the participants, one hundred 9-to-11-year-old girl students, took the...

introduction: poor sensitivity and poor signal to noise ratio because of low injected thallium dose and presence of scattered photons are the main problems in using thallium in scintigraphic imaging of the heart. scattered photons are the main cause of degrading the contrast and resolution in spect imaging that result in error in quantification. thallium decay is very complicated and photons ar...