The RF sections of Analog FM and Digital Radios primarily differ in the required linearity. If the transmitter amplifiers and attendant switching functions are not extremely linear, AM to AM and AM to PM conversion can cause serious deterioration of Bit Error Rate (BER) and an increase in intersymbol interference (ISI). Higher order QAM Systems such as 64-QAM and 256-QAM require even higher lev...

The paper evaluates the effect of multipath propagation on broadband terrestrial free-space optical links. At 10 Gbs the pulse duration is 0.1 ns for binary signaling and multipath propagation during fog events may affect the channel bandwidth and cause intersymbol interference in the receiver. The analysis is based on single-scattering approximation and semi-analytical solution, which is compu...

This paper presents the study and the realization at IETR of a high data rate 60 GHz wireless communications system. The system uses a simple single carrier architecture. The receiver architecture is based on a differential demodulation which minimizes the intersymbol interference (ISI) effect and a signal processing unit composed of a joint frame and byte synchronization block and a convention...

A new and efficient class of nonlinear receivers is introduced for digital communication systems. These “iterated-decision” receivers use optimized multipass algorithms to successively cancel interference from a block of received data and generate symbol decisions whose reliability increases monotonically with each iteration. Two variants of such receivers are discussed: the iterated-decision e...

Relying on space-time linearly precoded orthogonal frequency-division multiple access (OFDMA) and exploiting both transmit and receive antenna diversity, we design herein multirate transceivers that guarantee deterministic symbol recovery with diversity gains regardless of the (possibly unknown) frequency-selective finite impulse response (FIR) channels and multiuser interference. Our approach ...

Currently, Communication via Diffusion (CvD) is one of the most prominent systems in nanonetworks. In this paper, we evaluate the effects of two major interference sources, Intersymbol Interference (ISI) and Co-channel Interference (CCI) in the CvD system using different modulation techniques. In the analysis of this paper, we use two modulation techniques, namely Concentration Shift Keying (CS...

Ideas of message passing are applied to the problem of removing the effects of intersymbol interference (ISI) from partial-response channels. Both bit-based and state-based parallel message-passing algorithms are proposed. For a fixed number of iterations less than the block length, the bit-error rate of the statebased algorithm approaches a nonzero constant as the signalto-noise ratio (SNR) ap...

Maximization of the energy transfer ratio for timelimited signals over linear channels is considered. The case of linear channels with rational transfer function is addressed and a general procedure for the analytic solution of the maximization problem is outlined. The maximum energy transfer ratio over a fixed time interval is evaluated in some cases of interest. Two performance metrics—the en...

A rateless transmission architecture is developed for communication over Gaussian intersymbol interference channels, based on the concept of super-Nyquist (SNQ) signaling. In such systems, the signaling rate is chosen significantly higher than the Nyquist rate of the system. We show that such signaling, when used in conjunction with good “off-the-shelf” base codes, simple linear redundancy, and...

In this paper, we propose an optimized delay diversity (ODD) scheme for fading intersymbol interference (ISI) channels. We derive a cost function for optimization of the ODD transmit filters and we provide a steepest descent algorithm for iterative calculation of the filter coefficients. In addition, an upper bound on the cost function is derived and employed to prove the asymptotic optimality ...