Search results for "COD"
showing 10 items of 2985 documents
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…
Ethical managers in ethical organisations? The leadership-culture connection among Finnish managers
2013
PurposeThe main aim of the present study is to discover whether the managers’ self‐evaluations of their ethical leadership style are associated with their assessments of the ethical organisational culture (measured with an eight‐dimensional Corporate Ethical Virtues‐model). It aims to hypothesise that the more ethical the managers evaluate their own leadership style to be, the higher evaluations they give on the ethical culture of their organisation. The underlying assumption is that ethical managers can enhance the ethical culture by behaving in accordance with their own values.Design/methodology/approachThis quantitative research was based on a questionnaire study with 902 respondents thr…
A comparative evaluation between dermatoglyphic patterns and different terminal planes in primary dentition
2018
Background To assess the correlation between different dermatoglyphic patterns with the terminal planes in deciduous dentition. Material and methods 300 children who are 3-6 years old with complete primary dentition were recruited and the pattern of molar terminal plane was recorded in the proforma. Finger prints of the distal phalanges of these subjects were recorded using ink and roller method and were analysed for the finger print pattern by a forensic specialist. The pattern were classified based on classification given by Galton. The finger ridge counts were also measured. Results Ulnar loop pattern was the most predominant dermatoglyphic pattern. Absence of arch pattern in ring and li…
Blind source separation based interference suppression schemes for OFDM and DS-CDMA
2015
In statistical wireless signal processing, extraction of unobserved signals from observed mixtures can be achieved using Blind Source Separation (BSS) algorithms. Orthogonal Frequency Division Multiplexing (OFDM) and Direct Sequence-Code Division Multiple Access (DS-CDMA) can be pronounced as the well established predominant air interface communication techniques. Consequences of an effort taken and counteractive solutions to diminish the undesirable influences encountered within the wireless air interface of those techniques with aid of BSS schemes are disclosed. Filter coefficients for the receiver are ascertained with the support of a set of energy functions and the iterative fixed point…
Efficient Simulation of Orthogonal Multicarrier Transmission over Multipath Fading Channels
2011
Filterbank orthogonal multicarrier transmission schemes, such as OFDM/OQAM, are currently under intense study for their spectral efficiency and suitability for the physical layer of Cognitive Radio. Nonetheless, the mathematical description of the signal is cumbersome, and closed form expressions for performance figures are not available, so performance analysis on fading channels has to be performed by means of simulations. We propose an algorithm for simulating the received signal over multipath frequency selective fading channels, based on Taylor series expansion of the channel transfer function. The proposed method is compared to the state-of-the-art FFT-based method in terms of computa…
A 16QAM super-orthogonal space-frequency code for broadband mobile communication systems with two transmit antennas
2010
We combine our previously designed 32-state super-orthogonal space-time trellis code (SOSTTC) with orthogonal frequency division multiplexing (OFDM) to build a broadband mobile communication system having a spectral efficiency that amounts to 4 bits/s/Hz depending on the length of the cyclic prefix used to avoid interframe interference. The transmitter is equipped with two antennas, where the OFDM frames they transmit are not independent, as they carry the same information in an orthogonal form. The 2N OFDM tones are grouped in N pairs of tones. Each group of two tones transmits the entries of a 2×2 orthogonal matrix. In our case, the entries are symbols taken from the rectangular 16-point …
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…
On the role of the upper part of words in lexical access: evidence with masked priming.
2012
More than 100 years ago, Huey (1908) indicated that the upper part of words was more relevant for perception than the lower part. Here we examined whether mutilated words, in their upper/lower portions (e.g., , , , ), can automatically access their word units in the mental lexicon. To that end, we conducted four masked repetition priming experiments with the lexical decision task. Results showed that mutilated primes produced a sizeable masked repetition priming effect. Furthermore, the magnitude of the masked repetition priming effect was greater when the upper part of the primes was preserved than when the lower portion was preserved –this was the case not only when the mutilated words we…