Search results for "communication channel"
showing 10 items of 349 documents
Weak decay of Λ hypernuclei
1998
Abstract We review recent developments concerning the weak decay of Λ hypernuclei. New studies covering the mesonic decay channel as well as recent models for the non-mesonic one are discussed and compared with experimental data. The puzzle of the neutron- to proton-induced decay ratio, Γ n Γ p , is addressed in connection to the two-nucleon induced decay channel and proposals for more efficient experimental analyses of this ratio are made.
S11 RESONANCES IN A COUPLED-CHANNEL DYNAMICAL MODEL
2005
A self-consistent analysis of pion scattering and pion photoproduction within a coupled channels dynamical model is presented. The results indicate the existence of a third and a fourth S11 resonance with the masses 1846±47 and 2113±70 MeV . In the case of pion photoproduction, we found that background contributions to the imaginary part of the S-wave multipole become large and negative in the region of the S11(1535) resonance. Due to this fact, much larger resonance contributions are required in order to explain the results of the recent multipole analysis. For the first S11(1535) resonance we obtain a value of 72±2×10-3 GeV -1/2 for the electromagnetic helicity amplitude A1/2.
MUSIC-LS Modal Channel Estimation for an OFDM-OQAM System
2008
Orthogonal frequency division multiplexing based on offset quadrature amplitude modulation (OFDM-OQAM) signaling over frequency selective multipath channels shows inter-symbol interference (ISI) and Inter-Channel Interference (ICI) that degrade its performance. Channel equalization and channel estimation are needed to combat these intrinsic interferences. In this paper a novel modal channel estimator based on the MUltiple signal classification (MUSIC) and least squares (LS) algorithms for a wideband passband OFDM-OQAM signaling over static multipath channels is presented. The effects of the frequency selective channel on the received signal are described considering a wideband OFDM-OQAM sys…
MUSIC-based modal channel estimation for wideband OFDM-OQAM
2008
Orthogonal frequency division multiplexing based on offset quadrature amplitude modulation (OFDM-OQAM) over wideband frequency selective multipath channels suffers from inter-symbol interference (ISI) and inter-carrier interference (ICI) that degrade its performance. Channel estimation and equalization are needed to combat these interferences. In this paper a novel channel estimator for passband OFDM-OQAM signaling over wideband multipath channels, which is based on multiple signal classification (MUSIC) with the Spatial Smoothing technique is presented. Numerical simulation results are presented in the low number of subcarriers, i.e. wideband, scenario.
Complaining at the Store or Through Social Media: The Influence of the Purchase Channel, Satisfaction, and Commitment
2017
In the current omnichannel retail environment, customers have multiple channels to interact with firms to search for information, purchase, and after-sales. Within those channel social media can play a significant role, particularly as complaint channels. The aim of this paper is to analyze whether the choice to complain face-to-face or through social media depends on the purchase channel chosen and the satisfaction and commitment with the retailer. With data from an online panel our results show that the complaint channel tends to be the same as the channel chosen for purchase; moreover, satisfaction is positively related to complaining at store and negatively related to complaining throug…
Advance booking across channels: The effects on dynamic pricing
2021
This research analyzes the effects of advance booking and channel type on hotel rates. While this relationship has been addressed in the literature, most studies take a partial approach by focusing only on one distribution channel or one destination. This study fills this gap by analyzing the price dynamics for four channels and multiple destinations. The data set consists of 39,363 bookings for 1085 hotels over 27 consecutive months. We used two-stage least squares to solve potential endogeneity issues, and the results proved that distribution channel, hotel type and hotel size have an influence on the effect of advance booking on hotel rates. Critical managerial implications are discussed…
Designing Precoding and Receive Matrices for Interference Alignment in MIMO Interference Channels
2017
Interference is a key bottleneck in wireless communication systems. Interference alignment is a management technique that align interference from other transmitters in the least possibly dimension subspace at each receiver and provides the remaining dimensions for free interference signal. An uncoordinated interference is an example of interference which cannot be aligned coordinately with interference from coordinated part; consequently, the performance of interference alignment approaches are degraded. In this paper, we propose a rank minimization method to enhance the performance of interference alignment in the presence of uncoordinated interference sources. Firstly, to obtain higher mu…
A Wideband One-Ring MIMO Channel Model Under Non-Isotropic Scattering Conditions
2008
In this paper, we present a wideband one-ring multiple-input multiple-output (MIMO) channel model for non-isotropic scattering environments. The model is designed in such a way that the delay power spectral density (PSD) of the resulting reference channel model is identical to a given delay PSD. Furthermore, we present an efficient deterministic channel simulation model obtained by using the principle of deterministic channel modeling. The statistical properties of both the reference model and the simulation model are also studied. Analytical expressions will be presented for the temporal autocorrelation function (ACF), the two-dimensional (2D) space cross-correlation function (CCF), and th…
An OFDM Receiver Exploiting Multipath Diversity
2008
We propose a novel receiver structure, to be employed with standard Orthogonal Frequency Division Multiplexing transmitters, capable of exploiting the multipath diversity of wireless channels. The proposed technique is based on cancellation of inter-block interference arising in the guard interval and linear detection techniques. It features a low implementation complexity and is easily generalized to MIMO systems and non-linear detection techniques.
Observation of s-Channel Production of Single Top Quarks at the Tevatron
2014
We report the first observation of single-top-quark production in the s channel through the combination of the CDF and D0 measurements of the cross section in proton-antiproton collisions at a center-of-mass energy of 1.96 TeV. The data correspond to total integrated luminosities of up to 9.7fb-1 per experiment. The measured cross section is σs=1.29-0.24+0.26pb. The probability of observing a statistical fluctuation of the background to a cross section of the observed size or larger is 1.8×10-10, corresponding to a significance of 6.3 standard deviations for the presence of an s-channel contribution to the production of single-top quarks. © 2014 American Physical Society.