OFDM is one of the most widely used multi-carrier modulation technologies in wireless communication. However, case high mobility, orthogonality between sub-carriers destroyed due to existence time selective fading, and performance system greatly affected. In order reduce this effect, data can be pre-coding before modulation. The technique adopted paper Walsh-Hadamard transform (WHT). are distri...

This article describes a simple and inexpensive modem intended to link end users at 76.8kBit/s to the high speed backbone network. The modem can be connected to standard PC’s using the Universal Serial Bus (USB).

This article describes a simple and inexpensive modem intended to link end users at 76.8kBit/s to the high speed backbone network. The modem can be connected to standard PC’s using the Enhanced Parallel Port (EPP) interface.

Status of this Memo This document specifies an Internet standards track protocol for the Internet community, and requests discussion and suggestions for improvements. Please refer to the current edition of the "Internet Official Protocol Standards" (STD 1) for the standardization state and status of this protocol. Distribution of this memo is unlimited. Abstract The Layer 2 Tunneling Protocol (...

T Few dense underwater acoustic sensor networks (UWSN) currently exist because existing commercial acoustic modems are too expensive and power consuming. In order to enable the proliferation of UWSN, a new low-cost, low-power acoustic modem must be designed. This paper investigates the appropriate computational platform and presents the design of a complete FPGA implementation of a Frequency Sh...

background: the use of devices emitted microwave radiation such as mobile phones, wireless fidelity (wi-fi) routers, etc. is increased rapidly. it has caused a great concern; the researchers should identify its effects on people's health. we evaluated the protective role of vitamin c on the metabolic and enzymatic activities of the liver after exposure to wi-fi routers. material and methods: 70...