Volume 59, Nº 8 (2016)
- Ano: 2016
- Artigos: 7
- URL: https://journals.rcsi.science/0735-2727/issue/view/10882
Article
Channel capacity with suboptimal adaptation technique over generalized-K fading using marginal moment generating function
Resumo
In this paper we have computed the channel capacity for suboptimal adaptation technique over the generalized-K fading environment. The analytical expression for channel capacity in case of the truncated channel inversion with fixed rate (CTCIFR) has been exploited in terms of marginal moment generating function (MMGF) and its performance is evaluated over the generalized-K faded environment. The MMGF based approach for the computation of channel capacity has been validated with the reported literature for channel capacity in case of the channel inversion with fixed rate using the suboptimal adaptive technique.
Algorithms of 3D radio-wave imaging in airborne Doppler radar
Resumo
Estimation algorithms of coordinates of the Earth surface elements in 3D radio-wave imaging system based on the airborne Doppler radar during the low-altitude flight were proposed. In addition, the applicability of the algorithms was demonstrated by using the computer simulation method.
Statistical synthesis and analysis of the additive noise microwave radiometer with optimal structure
Resumo
An optimal algorithm for estimation of the brightness temperature of intrinsic thermal radio radiation of objects having different physical nature in additive noise microwave radiometer has been synthesized. A functional block diagram implementing this algorithm was developed. The limiting error of estimating the desired parameter was calculated, and the potential fluctuation sensitivity of the proposed radiometer was investigated.
Adaptive sequential detection of target trajectory using decision statistics of pips at the unknown signal-to-noise ratio
Resumo
Adaptive algorithms of multialternative sequential detection of target trajectory using the upper and lower thresholds and employing decision statistics of pips at the unknown signal-to-noise ratio (SNR) have been derived on the basis of the sequential criterion of simple complement. The application of lower thresholds made it possible to implement the procedure of discarding unsuccessful hypotheses. An adaptive two-alternative sequential algorithm of target track detection was developed using decision statistics of pips with SNR estimation by the criterion of error mean square minimum. The statistical simulation was used to analyze the algorithms for the case of target track detection on the basis of data of the surveillance radar that measures the range and radial velocity of target.
Application of model of mixture of probabilistic distributions for definition of the signals of radiophysical probing
Resumo
The article describes a model representation of radar probing data in form of a mixture of background and target samples, which is the sum of two random variables with very different parameters. For model development we research the behavior of the central moments of the distribution mix without assuming the distribution law form. An example it is described the detection of the signal at the output of compression system of chirp ionosonde.
About protection of power modules of multi-layer frequency converters
Resumo
In this paper we propose a solution of the problem related to match of level and shapes of pulses generated by microcontrollers with control signals of power transistor inputs. It is related to development of energy converters with application of pulse-width modulation. Also in this paper we analyze different existent methods of power modules protection with purpose of maximal efficient application of their power characteristics.
Performance analysis of the recording system of nonlocal biomechanical signals
Resumo
This study presents the performance analysis results of biotechnical system for recording nonlocalized biomechanical signals. The circuits for simulating the impact of the pressing force (applied to the body surface) on the input of signal transducer were considered both in the absence and in the presence of a supporting surface of transducer. The sensor design was shown to influence the reduction level of the impact of the pressing force applied to the body resulting in the specific effect on the transducer input. In addition, the effect of the sensitivity loss of the recording channel of nonlocal biomechanical signals on the reduction level was also evaluated.