This chapter considers the Multiband Orthogonal Frequency Division Multiplexing (MBOFDM) modulation and demodulation with the intention to optimize the Ultra-Wideband (UWB) system performance. OFDM is a type of multicarrier modulation and becomes the most important aspect for the MB-OFDM system performance. It is also a low cost digital signal component efficiently using Fast Fourier Transform ...

Constant-power adaptive transmission technique adopting UL-coded spectrally-precoded orthogonal frequencydivision multiplexing (SP-OFDM) signals with one tap zeroforcing equalization is studied on the flat fading channel. By jointly adapting the precoding order for spectral precoder and the component modulation for OFDM, constant-power ULcoded adaptive SP-OFDM is shown to outperform conventiona...

With its robustness against multipath fading, orthogonal frequency division multiplexing (OFDM) has become the modulation of choice for many modern wireless standards. However, OFDM is very sensitive to offsets in frequency and time. This makes synchronization an essential part of an OFDM system. This paper aims to motivate and analyze past work on OFDM synchronization techniques.

Layered asymmetrically clipped optical orthogonal frequency division multiplexing (ACO-OFDM) with high spectral efficiency is proposed in this paper for optical wireless transmission employing intensity modulation with direct detection. In contrast to the conventional ACO-OFDM, which only utilizes odd subcarriers for modulation, leading to an obvious spectral efficiency loss, in layered ACO-OFD...

In this paper we describe a coding, modulation, and spatial processing technique for fixed broadband wireless Internet access applications and provide examples of its performance. This technique is built on Orthogonal Frequency Division Multiplexing (OFDM) and is known as Vector OFDM (VOFDM). We compare VOFDM with conventional Single Carrier Modulation (SCM), and show that it provides substanti...

The Orthogonal Frequency Division Multiplexing (OFDM) is also known as multicarrier technology. Wideband digital communications in the recent past have increasingly utilized OFDM. It can withstand difficult channel circumstances, efficiently utilize spectrum resources, decrease ISI, and operate at a high data rate, among many other benefits. has been used several wireless wired communication sy...

In this paper, we evaluate the performance of BCH (Bose-ChaudhuriHocquenghem) correcting codes when used to protect data over a land mobile channel using OFDM (Orthogonal Frequency Division Multiplexing) modulation. To deal with memory channels, the Gilbert-Elliott (GE) model was considered to simulate a Rayleigh fading channel and BCH codes to analyse the error process. Relating GE parameters ...

AbstractLong haul transmission links evolve with the advent of new multiplexing and modulation schemes. We propose a new approach of dispersion compensated coherent optical orthogonal frequency division multiplexing scheme which is combined with quadrature amplitude modulation to double the data rate and spectral efficiency as transmitted in an optical OFDM system. Quadrature amplitude modulati...

Polarization mode dispersion (PMD) is a challenge for high-data-rate optical-communication systems. More researches are desirable for impairments that is induced by PMD in high-speed optical orthogonal frequency division multiplexing (OFDM) transmission system. In this paper, an approximately analytical method for evaluating the power penalty due to first-order PMD in optical OFDM with quadratu...

Multiple-input multiple output orthogonal frequency division multiplexing with index modulation (MIMO-OFDMIM) is novel multicarrier transmission technique which has been proposed recently as an alternative to classical MIMO-OFDM. In this scheme, OFDM with index modulation (OFDM-IM) concept is combined with MIMO transmission to take advantage of the benefits of these two techniques. In this work...