35 research outputs found
Calculation of runoff and soil erosion on the Tifran watershed, Polimlje, North-East of Montenegro
No full textSoil erosion is a growing problem in South East Europe and is creating a hazard to soil quality, environment and biodiversity. It is well-known fact that runoff, soil erosion and as consequence sedimentation, are decreasing a reservoirs capacity and that is noticeable in the region of Polimlje, where the studied watershed belongs. This is causing the new expenses to the weak economies of the Countries of this underdeveloped area. Ecological factors, which are the basis for the calculation of soil erosion intensity, we included in the simulation model. At the level of the watershed, the use of computer-graphic methods allowed the quantification of the environmental effects of runoff and soil erosion. Maximal outflow (incidence of 100 years) from the studied watershed, Qmax, was predicted on 31 m3/s. The value of the Z coefficient was calculated on 0.271 and according to the result the watershed belongs in the destruction category IV. The strength of the erosion process is low, and mixed erosion dominates in the studied area. The calculated soil losses were 277 m3 per year for the watershed, specific 115.5 m3/km2 per year. We have not evaluated proposed anti-erosion measures in the area because they have not been put into practice. This study shown that IntErO model is a useful tool for researchers in calculation of runoff and sediment yield at the level of the river basins in the South East European region
Sphere-Packing Modulated Space-Time Coding Using Non-Binary LDPC-Coded Iterative-Detection
No full textA recently proposed Space-Time Block Coding (STBC) signal construction method that combines orthogonal design with sphere packing, referred to here as (STBC-SP), has shown useful performance improvements over Alamouti’s conventional orthogonal design. In this contribution, we propose a purely symbol-based LDPC-coded scheme, demonstrating that the performance of STBC-SP systems can be further improved by concatenating sphere packing aided modulation with non-binary LDPC and by performing symbol-based turbo detection between the non-binary LDPC decoder and a rate-1 non-binary inner precoder. We also investigate the convergence behaviour of this symbol-based concatenated scheme with the aid of novel nonbinary Extrinsic Information Transfer (EXIT) charts. Finally, we demonstrate that in the investigated scenarios it requires 1-2dB lower power in comparison to equivalent effective throughput 0.5, 0.75 and 1 bit/symbol systems employing bit-based turbo detection
Joint iterative channel estimation and parallel interference cancellation for coded DS-CDMA
No full textA Purely Symbol-Based Precoded and LDPC-Coded Iterative-Detection Assisted Sphere-Packing Modulated Space-Time Coding Scheme
No full textIn this contribution, we propose a purely symbol-based LDPC-coded scheme based on a Space-Time Block Coding (STBC) signal construction method that combines orthogonal design with sphere packing, referred to here as (STBCSP). We demonstrate that useful performance improvements may be attained when sphere packing aided modulation is concatenated with non-binary LDPC especially, when performing purely symbol-based turbo detection by exchanging extrinsic information between the non-binary LDPC decoder and a rate-1 non-binary inner precoder. We also investigate the convergence behaviour of this symbol-based concatenated scheme with the aid of novel non-binary Extrinsic Information Transfer (EXIT) Charts. The proposed symbol-based turbo-detected STBC-SP scheme exhibits a 'turbo-cliff' at Eb/N0 = 5.0 dB and achieves an Eb/N0 gain of 19.2dB at a BER of 10-5 over Alamouti’s scheme
