Browsing by Publisher "Hindawi Publishing Corporation"
Now showing items 1-6 of 6
A low-complexity time-domain MMSE channel estimator for space-time/frequency block-coded OFDM systems Authors:
Publisher and Date:(Hindawi Publishing Corporation, 2006)Focusing on transmit diversity orthogonal frequency-division multiplexing (OFDM) transmission through frequency-selective channels this paper pursues a channel estimation approach in time domain for both space-frequency OFDM (SF-OFDM) and space-time OFDM (ST-OFDM) systems based on AR channel modelling. The paper proposes a computationally efficient pilot-aided linear minimum mean-square-error (MMSE) time-domain channel estimation algorithm for OFDM systems with transmitter diversity in unknown ...
Inverse Coefficient Problem of the Parabolic Equation with Periodic Boundary and Integral Overdetermination Conditions Authors:
Publisher and Date:(Hindawi Publishing Corporation, 2013)This paper investigates the inverse problem of finding a time-dependent diffusion coefficient in a parabolic equation with the periodic boundary and integral overdetermination conditions. Under some assumption on the data the existence uniqueness and continuous dependence on the data of the solution are shown by using the generalized Fourier method. The accuracy and computational efficiency of the proposed method are verified with the help of the numerical examples.
Publisher and Date:(Hindawi Publishing Corporation, 2008)We propose a joint MAP channel estimation and data detection technique based on the expectation maximization (EM) method with paralel interference cancelation (PIC) for downlink multicarrier (MC) code division multiple access (CDMA) systems in the presence of frequency selective channels. The quality of multiple access interference (MAI) which can be improved by using channel estimation and data estimation of all active users affects considerably the performance of PIC detector. Therefore data and ...
Preparation and characterization of self-assembled thin film of MPS-capped ZnS quantum dots for optical applications Authors:
Publisher and Date:(Hindawi Publishing Corporation, 2012)For this study we prepared colloidal ZnS quantum dots using 3-mercaptopropyltrimethoxysilane (MPS) as the capping agent. Colloidal ZnS quantum dots were directly deposited on glass substrates by a spin coating process. Therefore self-assembled films made of ZnS quantum dots in a SiO2 network were obtained using only one production step. The films were heat-treated at 100 degrees 125 degrees 150 degrees 175 degrees and 200 degrees C in an N-2 atmosphere. The results showed that the dimension of ...
The effect of film thickness and TiO2 content on film formation from PS/TiO2 nanocomposites prepared by dip-coating method Authors:
Publisher and Date:(Hindawi Publishing Corporation, 2012)Steady-state fluorescence (SSF) technique in conjunction with UV-visible (UVV) technique and atomic force microscope (AFM) was used for studying film formation from TiO2 covered nanosized polystyrene (PS) latex particles (320 nm). The effects of film thickness and TiO2 content on the film formation and structure properties of PS/TiO2 composites were studied. For this purpose two different sets of PS films with thicknesses of 5 and 20 mu m were prepared from pyrene-(P-) labeled PS particles and ...