Orthogonal Frequency Division Multiplexing (OFDM) is one of recent years multicarrier modulation used in order to combat the Inter Symbol Interference (ISI) introduced by frequency selective mobile radio channel. The circular extension data symbol, commonly referred as cyclic prefix key elements an OFDM transmission scheme. This paper study influence duration on BER performance OFDM-VCPL (Ortho...

Abstract— Orthogonal frequency division multiplexing (OFDM) is an important technique to support high speed transmission of broadband traffic in wireless networks, especially broadband wireless local area networks (LANs). Based on OFDM, a new multiple access scheme, called OFDM-TDMA with subcarrier allocation (OFDMTDMA/SA), is introduced in this paper. It provides more flexibility in resource a...

Orthogonal Frequency Division Multiplexing (OFDM) faces the Peak-to-Average Power Ratio (PAPR) problem that is a main disadvantage in multicarrier transmission system. Here in this paper an attempt is made to improve the spectrum efficiency (SE), and energy efficiency (EE) in orthogonal frequency division multiplexing (OFDM) systems, Simulation results show that the OFDM system with PAPR reduct...

Orthogonal frequency division multiplexing (OFDM) is a method of encoding digital data over a multiple carrier frequencies. OFDM stands for Orthogonal Frequency Division Multiplexing and also it is a modulation technique for transmitting large amounts of digital data over a radio wave. OFDM for wireless communications is used for PAPR reduction techniques. KeywordsOFDM, Peak-Average-Power Ratio...

Orthogonal frequency division multiplexing (OFDM) is particularly divided to three varieties. Cyclic prefix OFDM, zero padding OFDM, and time domain synchronous OFDM. Compared to CP OFDM, TDS-OFDM has higher spectral efficiency and faster synchronization. This paper reviewed however efficiently uses the compressive sensing (CS) theory to resolve those problems. During this paper, a noise cancel...

Orthogonal Frequency Division Multiplexing (OFDM) is a digital multicarrier transmission technique which is based on Frequency division Multiplexing. Several multimedia standards uses Time Frequency Training Orthogonal Frequency Division Multiplexing (TFT-OFDM) as the key modulation technique. This paper introduces a high accurate, low complexity compressive sensing (CS) based channel estimatio...

Orthogonal Frequency Division Multiplexing (OFDM) is a well-known technique for the broadband wireless communication system. However, a main problem in OFDM is its vulnerability to frequency offset errors due to which the orthogonality is destroyed that result in Inter carrier Interference (ICI). ICI causes power leakage among subcarriers thus degrading the system performance. This paper studie...

Orthogonal signal-division multiplexing (OSDM) is a newly emerged modulation scheme which provides a generalized framework unifying conventional orthogonal frequency-division multiplexing (OFDM) and single-carrier frequency domain equalization. In this letter, a space-frequency block coding (SFBC) scheme based on OSDM is proposed for time-varying underwater acoustic channels. The receiver proce...

Orthogonal Frequency Division Multiplexing (OFDM) is a special form of multicarrier modulation scheme, which divides the entire frequency selective fading channel into many orthogonal narrow band flat fading sub channels. Orthogonal Frequency Division Multiplexing (OFDM) is considered to be a promising technique against the multipath fading channel for wireless communications [1]. However, OFDM...

This work explores the performances of Space-Time and Space Frequency Coded Orthogonal Frequency Division Multiplexing (OFDM) with simple two branches transmit diversity scheme. The combination of multiple-antenna and orthogonal frequency division multiplexing (OFDM) provides reliable communications over frequency selective fading channels. We focus on the application of space-time block codes ...