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This paper considers a sequential estimation and sensor scheduling problem with one sensor and one estimator. The sensor makes sequential observations about the state of an underlying memoryless stochastic process, and makes a decision as to whether or not to send this measurement to the estimator. The sensor and the estimator have the common objective of minimizing expected distortion in the estimation...
In this paper, we focus on the design of Non Uniform Constellations (NUC) in the context of Layered Division Multiplexing (LDM) proposed recently for digital television systems. Because the Physical Layer Pipe for which the Non Uniform Constellation is designed can be used with or without Layered Division Multiplexing, it is important to design a constellation optimized for the waterfall Signal to...
In this paper we introduce an scheme which combines device-to-device communications nodes which act as relays for a cellular user (CU) located on the cell boundary. The proposed system works as an overlay cellular network. The CU having weak channel towards the base station exploits the availability of a pair of wireless terminals intending to communicate directly with each other. These intermediate...
Abstract-The capacity of the intensity-modulation directdetection (IM-DD) optical broadcast channel (OBC) is investigated. The OBC is modeled as a Gaussian channel with input-independent noise and both average and peak input constraints. Outer and inner bounds on the capacity region are derived. The outer bounds are based on Bergmans' approach. The inner bounds are based on superposition coding with...
Undersea acoustic links are highly complex due to the various propagation effects like the spreading, multipath, intersymbol interference, fading, etc.. Orthogonal frequency division multiplexing is found to be a good choice to combat intersymbol interference. It enables simpler equalization as well. Coding can be used in conjunction with OFDM to achieve error correction, improved security as well...
In this paper, simultaneous wireless information and energy transmission is studied from an information theoretic standpoint. The main contribution is twofold: (i) the capacity-energy region of the memoryless Gaussian multiple access channel is fully characterized; and (ii) the maximum sum-rate that can be achieved when a minimum energy level is required at the input of the receiver is determined...
This paper studies the optimal transmission of scalable multimedia sources over multiple-input multiple-output channels. First, we derive the outage probability of a space-time code for an arbitrary piecewise-linear diversity-multiplexing tradeoff function. We next prove that, as long as a crossover point of the outage probabilities of two space-time codes exists, then as the spectral efficiency increases,...
We investigate the problem of direction of arrival (DOA) estimation from turbo-coded square-QAM- modulated signals. We propose a new code-aided (CA) maximum likelihood (ML) direction finding technique that exploits the soft information obtained from the soft-input soft-output (SISO) decoder in the form of log-likelihood ratios (LLRs). Unlike standard estimation techniques, the proposed method improves...
The performance of dual-carrier 400G solutions based on three high-order quadrature amplitude modulation (QAM) formats (8/16/32-QAM) is investigated on the same platform. We first study the benefit and penalty differences of Gray and differential coding, and then experimentally compare OSNR sensitivities and transmission performance using flexible transceiver configuration and the same EDFA-only SSMF...
In this paper, we study a joint source and relay pre-coding technique for multiuser multi-relay that help to maximize sum rate (SR) for Multiple-Input Multiple-Output (MIMO) link. Here we proposed two-hop precoding technique by implementing Zero-Forcing (ZF) as source precoder and Dirty Paper Coding (DPC) as relay precoder. We show performance by simulating and show that ZF-DPC (i.e., ZF at source...
This paper presents a new coding scheme that considerably increases the efficiency of the channel in multicast setting. Specifically, we study the scenario where three terminals exchange their messages via a satellite gateway. The main difference between the proposed scheme and conventional three-way relay channel is the use of joint channel and network coding. This allows three terminals to transmit...
The transmit signal with good performance is the precondition of the excellent multiple-input and multiple-output (MIMO) synthetic aperture radar (SAR). In order to obtain waveforms of MIMO SAR based on linear frequency modulation with higher tolerance of receiver noise, the improved non-dominated sorting genetic algorithm II (NSGA-II) with elite strategy is proposed. Application of orthogonal linear...
Cooperative communication is a bright technology to acquire diversity gain in wireless terminals by sharing their antennas. With the fixed amplify-and-forward (AF) mode, relay node always helps to relay the data of the source node with unchanged transmission power. Judging from the power efficiency, it is obviously not optimal, particularly when channel states are quite good. An adaptive AF mode is...
A new transmission scheme is designed to maximize average spectral efficiency in a MIMO link considering instantaneous bit error rate (BER) and total power constraints. Discrete link adaptation using adaptive modulation and coding (AMC) is utilized to combat multipath fading which is implementable in practical systems. ZF receiver is employed by which MIMO channel becomes equivalent to several parallel...
We apply linear block-codes across 228-bit, PDM-64QAM spatial super-channels in a 19-core fiber and observe upto 3 dB reduced OSNR requirement and additional transmission reach of 55% at BER=3.8×10−3 and 122% at BER=1×10−3 for a 10.5% code overhead.
By pairing the mid and edge sub-bands of each channel, the penalty due to inter-channel-interference can be mitigated for a superchannel. Experimental results show that the proposed method offers 1.5-dB Q2 improvement after 3840-km transmission with 1GHz channel overlap.
Through the expansion of non-Gray-mapping symbols, the pre-FEC and post-FEC Q-factors of the proposed optimized Circle-8QAM outperform Circle-8QAM and Star-8QAM by ∼0.3 dB and ∼0.6dB at the coding rate of 0.8 in experiments.
We propose a linear transceiver scheme for the symmetric two-user multiple access channel with additive white Gaussian noise and quantized feedback. The quantized feedback link is modeled as an information bottleneck subject to a rate constraint. We introduce a superposition scheme that splits the transmit power of each user between an Ozarow-like code (designed for perfect rate-limited feedback)...
We study the transmission over a cloud radio access network, in which multiple base stations (BS) are connected to a central processor (CP) via finite-capacity backhaul links. Focusing on maximizing the allowed sum-rate, we develop a lattice based coding scheme that generalizes both compute-and-forward and successive Wyner-Ziv coding for this model. The scheme builds on Cover and El Gamal partial-decode-compress-and-forward...
In this paper, two issues in assessing the performance of superposition coding (SC) in the downlink Long Term Evolution (LTE) are investigated. The first issue is the prediction of user's signal-to-interference-plus-noise ratio (SINR) at the scheduler based on the user's channel state information (CSI) feedback, when the actual transmission scheme is different from the scheme used for CSI computation...
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