Orthogonal Frequency Division Multiplexing (OFDM) is well known as an efficient technology for wireless communications and is widely used in many of the current and upcoming wireless and wireline communication standards. However, it has some intrinsic drawbacks, e.g., sensitivity to the inter-carrier interference (ICI) and high peak-to-average power ratio (PAPR). Additionally, the cyclic prefix...

Most transmission schemes for MIMO channels assume (i) a block fading channel without delay spread and (ii) availability of channel state information at the receiver. Here, we extend the space-time motrir modulation (STMMj scheme and the iterative demodulation algorithm that we introduced previously to unknown, doubly selective MlMO channels, i.e., delayDoppler-spread MlMO channels that are unk...

The local scattering function (LSF) and the generalized channel correlation function have recently been introduced as intuitive and useful statistical characterization of fading channels that do not satisfy the usual WSSUS assumption [1]. In this paper, we present a generalized LSF and we demonstrate that for the subclass of practically relevant doubly underspread non-WSSUS channels, several us...

We consider the problem of multiuser detection for DSCDMA in doubly-selective (timeand frequency-selective) channels, and propose a time-varying multiuser detector (TVMUD) to solve this problem. Using a basis expansion model (BEM) to model the doubly-selective channel and the TVMUD, we derive a closed-form expression for the BEM coefficients of the TV-MUD as a function of the BEM coefficients o...

Wireless communications play a significant role in facilitating several mobile applications like unmanned aerial vehicles, high-speed railway, and vehicular communications. Particularly, the concept of connected vehicles brings new level connectivity to vehicles. Along with novel on- board computing sensing technologies, networks serve as key enabler intelligent transportation systems smart cit...

There is a trend towards flexible radios which are able to cope with a range of wireless communication standards. For the integrated processing of widely different signals — including single-carrier, multicarrier, and spread-spectrum signals — monolithic baseband receivers need universal formats for the signal representation and channel description. We consider a reconfigurable receiver archite...

It was widely believed that knowledge of channel state information (CSI) at the receiver imposes a sharp cut-off on the achievability of coherent capacity at large bandwidths (or low SNRs). Recent works have shown that by either employing an explicit training-based scheme or an implicit channel-learning and communication scheme, rates intermediate between the coherent and the non-coherent extre...