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The following topics were dealt with: advanced communication technology; multimedia wireless LAN; software radio; OFDMA; IEEE 802.16e systems; IEEE 802.11e QoS stations; channel estimation; OFDM; wireless ubiquitous networks; ad hoc networks; automatic Web services; information gathering protocol; mobile communications; RFID; ALOHA; IEEE 802.11n; VisuGATOR; proxy signature scheme; single carrier modulation...
Orthogonal frequency division multiplexing (OFDM) is a multi-carrier digital modulation technique that has been under extensive study and research in recent years, in terms of considering its various advantages in combating the severe effects of the frequency selective fading. However, the OFDM system suffers from the strong sensitivity to the nonlinear distortion, introduced by the transmitting high...
Integrated environment of wireless network can provide a ubiquitous and continuous communication for voice over Internet protocol (VoIP) service. However, the major problems, which VoIP performs over wireless networks, are varying delay of each packet, high packet loss rate and handoff. This paper proposed an adaptive QoS playout (AQP) algorithm to offer a high quality wireless VoIP service. AQP integrates...
Enlightened by fast correlation attacks algorithm (FCAA) which is a well-known attacking method on stream ciphers, we demonstrate the novel PN sequence acquisition based on its correlation property in this paper. By this approach, we can acquire a long PN code with a short observation interval. To evaluate the performance of our method, we have performed some simulations. Simulation results show that...
Telecommunication devices are getting smaller and smaller, thus the size of the antenna which is the heart of the communication must be small too. Microstrip antenna was developed to fit this criteria. In this paper, a new E-shaped driver based on the quasi-Yagi antenna is presented. This microstrip antenna is realized on a dielectric-constant substrate with epsir = 4.4. The size of the new proposed...
The digital method for symbol timing recovery has been used for several years and many scholars have proposed a great deal of methods for it. This paper describes the fundamentals of interpolation for timing recovery, and compares the differences between the two upsampling: zero-insertion expander and zero-order-hold expander used before the symbol timing interpolation. It is shown that, through simulation,...
The rapid spread of IP-based access technologies as well as the move towards core network convergence with IMS has led to an explosion in multimedia content delivery across packet networks. Although this transition has led to a much wider and richer service experience, there is also increased concern related to media protection and secure delivery of content that is sent over networks in digital form...
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