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In this paper, the CORDIC-based OFDM baseband receiver is proposed to fulfill the joint carrier synchronization and channel equalization algorithm. The versatile arithmetics of CORDIC are employed to realize various baseband operations, including “gain compensation”, “phase compensation”, “initial gain and phase estimation”, and “derotator”. The CORDICs are configured to perform these computations...
A novel, real-time and robust occupancy extraction system is going to be presented in this paper. The main contribution of the paper is to introduce a novel camera calibration algorithm to a multi-space area. The proposed calibration method is accurate, efficient and free of any error propagation among cameras' calibrations, without usage of overlapping areas. Also, the paper introduces a new virtual...
This paper addresses the area coverage problem of a 3D-space by a group of UAVs, equipped with omnidirectional cameras. The terrain morphology is assumed known to each UAV which has a maximum flight-altitude. A gradient-based distributed control law is provided, relying on a 3D-visible Voronoi-partitioning scheme, which converges monotonically to a local UAV topological-configuration in terms of the...
Choosing a polarimetric radar detector which exhibits well on detection performance and is easy to implement simultaneously is significant to the polarimetric radar target detection in reality. In this paper, we analyze and compare the detection performances and implementation difficulties of optimal polarimetric detector (OPD), polarimetric whitening filter (PWF), optimal span detector (OSD), polarimetric...
We focus on the dictionary learning problem for the analysis model. A simple but effective algorithm based on Nesterov's gradient is proposed. This algorithm assumes that the analysis dictionary contains unit ℓ2 norm atoms and trains the dictionary iteratively with Nesterov's gradient. We show that our proposed algorithm is able to learn the dictionary effectively with experiments on synthetic data...
We study the distance optimal assignment of n mobile robots to an equal number of targets under communication and target-sensing constraints. Extending previous results over uniform distributions, we show that when the robots and targets assume the same but arbitrary distribution over the unit square, a carefully designed distributed hierarchical strategy has expected travel distance that matches...
We consider several rigorously defined network tomography problems from applications ranging from communication networks, to social networks. The universal abstraction we develop involves the inference of various network structural and parametric properties form observations of certain “probing” processes from a subset of network nodes which we call the boundary nodes of the network. We show that...
The D-Wave quantum computer is designed to solve a specific class of problems — The Quadratic Unconstrained Binary Optimization (QUBO) problem. One of the key processes in this pathway to the solution consists in embedding the problem graph into a hardware graph. It is a nontrivial task to determine whether a problem graph is minor embeddable in a hardware graph. One method that singles out cases...
In this paper, we propose a new time-domain design of an Unknown Input Full Order Observer (UIFOO). The considered systems are delayed singular ones with known and unknown inputs. The time delay are of two kinds. The state delay is variable but the known input delay can be variable or constant. The proposed approach is based on the unbiasedness of the estimation error and Lyapunov-Krasovskii stability...
A connected Dominating Set (CDS) can be used as a backbone in a mobile ad hoc network (MANET) where a fixed communication infrastructure does not exist. Creating a virtual backbone within a MANET can reduce routing overhead and enhance scalability. Most CDS algorithms that exist today use a heuristic approach to try and find a Minimum CDS (MCDS). These approaches generally assign nodes with a large...
This paper aims at maximizing the lifetime of wireless sensor networks (WSN) in tree topology assuming limited energy of the battery at each sensor. We formulate the linear programming problem for maximizing the lifetime for a given tree topology, having as variables the number of times in which each node communicates with the base station. For a given tree, the policy that maximizes the lifetime...
In this paper, we compare the performance of block-diagonalization and regularized block-diagonalization precoding, assuming quantized channel state information (CSI) at the transmitter as obtained from limited receiver feedback. We identify the necessary CSI for the calculation of the precoders and propose quantization strategies to efficiently represent the CSI in the corresponding Grassmannian...
We consider an uplink system where multiple users have independent private channels plus a randomly accessible common channel. Moreover, each user is powered by some renewable energy sources via an energy harvester. Due to the variation of channel gains and energy arrivals, each transmitter could opportunistically wait for a better channel state and a higher energy level by postponing transmissions...
In this work we study the properties of the optimal Probability Mass Function (PMF) of a discrete input to a general Multiple Input Multiple Output (MIMO) channel. We prove that when the input constellation is constructed as a Cartesian product of 1-dimensional constellations, the optimal PMF factorizes into the product of the marginal 1D PMFs. This confirms the conjecture made in [1], which allows...
In this paper, the price of anarchy (PoA) and the price of stability (PoS) of a game arising in a two-user decentralized interference channel (DIC) with noisy feedback in which transmit-receiver pairs seek an optimal individual transmission rate are fully characterized. In particular, it is shown that in all interference regimes, there always exists at least one Pareto optimal Nash equilibrium (NE)...
In this paper, the problem of optimal power allocation in Cognitive Radio (CR) Multiple Input Multiple Output (MIMO) systems is treated. The focus is on providing limited feedback solutions aiming at maximizing the secondary system rate subject to a constraint on the average interference caused to primary communication. The limited feedback solutions are obtained by reducing the information available...
In this paper, we study relay and cooperative data gathering wireless sensor networks, where the system's output is the outcome of information fusion that is not only performed at the final destination, but is first distributed among several intermediate processing nodes. We propose a selective stream fusion procedure at clustering and sink nodes, that aims to enhance the decoding performance as well...
In this paper, the performance of the conventional Decision Feedback (DFE) equalizer as well as the Volterra DFE is investigated in the context of intensity modulated direct detection optical communications links, when non-return to zero on-off keyed (NRZ-OOK) and optical differential encoded phase shift keyed (NRZ-DPSK) transmission is employed. The DFE is used to mitigate either the residual chromatic...
Modern large-scale distributed storage systems utilize erasure codes to store only cold data, i.e., rarely access data such as click logs. However, a major portion of the data that is currently used for large-scale processing is hot data, data that are frequently accessed, in some cases by many users or system processes simultaneously. When storing hot data, replication seems to be the option of choice...
This paper proposes a novel sliding mode control approach applied on an active suspension system. This approach is based on a design of an Exponential Reaching Law which allows chattering reduction on control input, while keeping high tracking performance. The exponential term of the reaching law allows the sliding function to dynamically adapt to the system's variations.
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