OFDM has been proven to be a viable technique to overcome multipath fading in wireless channels. While OFDM systems convert a multipath fading channel into a series of equivalent flat fading channels they lack the inherent diversity available in multipath channels. Theoretically an uncoded OFDM system needs a simple receiver due to ISI free channel, but their performance deteriorates in the pre...

In wireless communication the effect of multipath as well as shadowing takes place simultaneously over the channel and this phenomena leads to composite fading. G-distribution is frequently encountered distribution in wireless fading environment. Combination of multipath fading and shadowing model are used as composite fading model. This composite fading model is named as Gdistribution. G-distr...

We present a new framework for code-division multiple access (CDMA) communication over fast fading mobile wireless channels. The performance of the RAKE receiver, which is at the heart of existing CDMA systems, degrades substantially under fast fading encountered in many mobile scenarios. Due to the time-varying nature of the fast fading channel, we employ joint time-frequency processing, which...

This paper presents a comprehensive overview of Ultra-Wideband (UWB) measurements of all the empirical data available on various fading properties of the indoor radiowave communication channel. Our focus is on the essential propagation channel parameters which is used in the physics-based models. This overview is based on more than 50 measurement campaigns from 24 working groups in different co...

The performance analysis of UWB techniques with MC-SS (multicarrier spread spectrum) system working in multipath fading channel is investigated in this paper. The model of the multipath fading is characterized by Nakagami-m statistic distribution. We establish and derive the model for MC-CDMA systems working in correlated Nakagami-m fading channel. The average BER (bit error rate) is calculated...

In direct sequence-code division multiple accesses systems (DS-CDMA), the signals are transmitted over multipath channels that introduce fading. Multipath fading along with multiple access interference and intersymbol interference degrades the system performance. Further, simultaneous presence of multipath fading and shadowing leads to worsening of wireless channels. Moreover, experimental resu...

This work is devoted to the formulation and derivation of the κ − μ/gamma distribution which corresponds to A physical fading model. This distribution is composite and is based on the well known κ − μ generalized multipath model and the gamma shadowing model. A special case of the derived model constitutes the κ − μ Extreme/gamma model which accounts for severe multipath and shadowing effects. ...

This work is devoted to the formulation and derivation of the α−κ−μ/gamma distribution which corresponds to a physical fading model. The proposed distribution is composite and is constituted by the α−κ−μ non-linear generalized multipath model and the gamma shadowing model. It also constitute the basis for deriving the α−κ−μ Extreme/gamma model which accounts for non-linear severe multipath and ...

An ultra-wide-band (UWB) signal is characterized by a radiated spectrum with a very wide bandwidth around a relatively low center frequency. In this paper, we study the reduced fading margin property of UWB signals. To evaluate the fading margin, we compare the performance of UWB signals in an environment with only additive white Gaussian noise (AWGN) versus the performance of UWB signals in a ...

SUMMARY This paper proposes two space-time joint channel parameter estimation and signal detection algorithms for downlink DS-CDMA systems with multiple-input-multiple-output (MIMO) wireless multipath fading channels. The proposed algorithms initially use the space-time MUSIC to estimate the DOA-delays of the multipath channel. Based on these estimated DOA-delays, a space-time channel decoupler...