Spectral efficiency is the key factor for the development of future wireless communications. Recently, filter bank multicarrier (FBMC) modulations have attracted a lot of attention due to capability to efficiently cope with frequency selective channels. Much of the attention in the present literature emphasizes on the use of conventional orthogonal frequency division multiplexing (OFDM). Howeve...

This paper proposes an OFDM based adaptive modulation scheme employing variable coding rate (VCR OFDM AMS), which selects optimum modulation and coding scheme (MCS) realized by combination of several modulation schemes and coding rates. The OFDM AMS with multilevel transmit power control (OFDM AMS/MTPC) can realize high data rate transmission in the dynamic parameter controlled-orthogonal frequ...

As the generation grown up, designing of the wireless communication system towards providing best performance by the services such as high speed of data delivery, high capacity and high bit rate. MC-CDMA (Multi CarrierCode Division Multiple Access) is a desired technique for such cases, MC-CDMA gives best results by the combination of OFDM (Orthogonal Frequency Division Multiplexing) and CDMA (...

There has been greatly increasing interest in orthogonal frequency division multiplexing (OFDM) for broadband wireless transmission due to its robustness against multipath fading. However, OFDM signals have high peak-toaverage power ratio (PAPR), and thus, a power amplifier must be operated with a large input power backoff (IBO). Recently, OFDM combined with time division multiplexing (OFDM/TDM...

School of Enginnering and Architecture Department of Electrical, Electronic, and Information Engineering ”Guglielmo Marconi” OFDM-based Schemes for Next Generation Wireless Systems by Oltjon Kodheli The purpose of this study is to investigate two candidate waveforms for next generation wireless systems, filtered Orthogonal Frequency Division Multiplexing (fOFDM) and Unified Filtered Multi-Carri...

Orthogonal frequency division multiplexing (OFDM) is a multi-carrier transmission technique, which divides the available spectrum into many subcarriers, each one being modulated by a low data rate stream[1]. Compare with the traditional ways, the OFDM system has the features of resisting frequency selective fading and high frequency-band utility ratio and so on. OFDM has been successfully appli...

Orthogonal Frequency Division Multiplexing (OFDM) being a multi-carrier transmission, is one of the most superior technologies in wireless communication. In this paper, a brief overview of an OFDM system is explained. High Peak-to-Average Power Ratio (PAPR) is the major issue associated with an OFDM system, so a novel Partial Transmit Sequence (PTS) technique is proposed for PAPR reduction. The...

In this contribution, a direct comparison of the Offset-QAM-OFDM (OQAM-OFDM) and the Cyclic Prefix OFDM (CP-OFDM) scheme is given for an 802.11a based system. Therefore, the chosen algorithms and choices of design are described and evaluated as a whole system in terms of bit and frame error rate (BER/FER) performance as well as spectral efficiency and complexity in the presence of multipath pro...

I. INTRODUCTION Orthogonal frequency-division multiplexing (OFDM) [1] is one of the promising techniques for very high-speed data transmissions in a severe frequency-selective fading channel [2]. However, since OFDM uses a numerous number of narrowband orthogonal subcarriers to transmit data in parallel, the problem of high peak-to-average power ratio (PAPR) arise. To alleviate the PAPR problem...

Additive mapping scheme represents alternative signals of selected mapping (SLM) by linear combination of signals in time domain for peak to average power ratio (PAPR) reduction in orthogonal frequency division multiplexing (OFDM) system. It can reduce the computational complexity considerably without sacrificing PAPR reduction performances especially for the OFDM system with quadrature amplitu...