Capacity analysis of underwater acoustic MIMO communications

Multi-Input Multi-Output (MIMO) principle is based on transmitting digital data from Nt transmitters to Nr receivers within a frequency band. In the last decade, theoretical works and practical experiments in wireless and cellular networks have convincingly proved that MIMO has been a real find in digital communications. Nowadays, MIMO principle is being applied to underwater acoustic communications (UAC) and it is showing encouraging results. But very few research has been done on the relation between different parameters of MIMO and its gain. Our primary purpose in this project is to analyse the MIMO gain theoretically using Shannon capacity analysis and suggest ways to maximize capacity with limited bandwidth by varying other parameters . As we will show in the later pages of this project that underwater acoustic channel (UAC) is highly selective in frequency, data transmission cannot be increased by simply increasing the transmission bandwidth. This difficult situation can be found in wireless communication where there is an increasingly large requirement in high speed data transfer but available bandwidth is constrained by the frequency allocation law. In those communication fields where radio frequency is used , this bandwidth limitation problem has been overcome by introducing MIMO techniques, which provide significant gain in data transmission rate while keeping the transmission Bandwidth constant.In the previous years, the contribution of MIMO to UAC systems has mostly been thoroughly analyzed via spatial modulation or multi-carrier modulation. Initial simulation and experimental results have showcased a larger gain over conventional single input single output (SISO) but the results strongly vary depending on the modulation scheme chosen by us and the receiver algorithm as well as the underwater channel environment

Towards a synthesis of C<SUB>3</SUB>-tribenzohemifullerene, a C<SUB>42</SUB>H<SUB>18</SUB> fragment of [60]fullerene

A short, simple synthesis of C3-trinaphthotriphenylene 6, C42H24, from readily available precursors involving threefold Wittig reactions and threefold oxidative photocyclizations is reported; flash vacuum pyrolysis of 6 in the quest for C3-tribenzohemifullerene 5, C42H18, has so far led only to the formation of monobridged product 12, C42H22

Rotating Brane World Black Holes

A five dimensional rotating black string in a Randall-Sundrum brane world is considered. The black string intercepts the three brane in a four dimensional rotating black hole. The geodesic equations and the asymptotics in this background are discussed.Comment: 10 pages, minor changes, typos corrected and references adde

A synthetic approach towards Pinakene, a C28H14 fragment of [70] - fullerene

301-30

Wind Energy Conversion System Connected With Grid Using Permanent Magnet Synchronous Generator (PMSG)

ABSTRACT-This paper deals with permanent magnet synchronous generator (PMSG) based wind energy conversion system (WECS) integrated with grid with two back to back connected converters with a common DC link. The aim of this research is to model control of direct driven 1.5 MW wind turbine permanent magnetic synchronous generator (PMSG) which feeds alternating current (AC) power to the utility grid .The machine side converter is used to extract maximum power from the wind. In this paper a study of WECS is done by using a constant speed direct-driven wind turbine in Matlab. Moreover, by maintaining the dc link voltage at its reference value, the output ac voltage of the inverter can be kept constant irrespective of variations in the wind speed and load. An effective control techniques to extract maximum power from wind turbine is maximum power point tracking controller (MPPT), grid side controller also called voltage controller, pitch controller, phase lock loop controller (PLL) also used in this project, transformer used for isolation purpose, crow bar circuit used for protection the whole system. KEYWORDS-Permanent magnet synchronous generator(PMSG), wind energy conversion system(WECS), back to back PWM converter IGBT based, DC link capacitor, Direct-Driven, MPPT controller, PLL loop, generator side converter control, grid side converter control, pitch controller, crow bar protection and transformer

Skin mediated human papillomavirus infection in breast: A report of four cases

To address the ambiguity of different modes of human papillomavirus (HPV) transmission in breast, the immunohistochemical expression of two oncoproteins E6/E7 of HPV16 was analyzed in primary breast cancer (BC) and adjacent normal skin of 4 samples. The patients were of 35–55 years old having no previous history of cancer. The E6/E7 expressions were evident in both skin and BC. In skin, high/moderate cytoplasmic expressions of E6/E7 proteins were seen in all samples, whereas in BC, high/moderate cytoplasmic expressions of the proteins were observed in 2–3 samples. Thus, it seems that HPV infection in the breast may occur through the skin

Solid-Phase Catalysis: A Biomimetic Approach toward Ligands on Dendritic Arms to Explore Recyclable Hydroformylation Reactions

Peer reviewed: YesNRC publication: Ye

The systematic study of the influence of neutron excess on the fusion cross sections using different proximity-type potentials

Using different types of proximity potentials, we have examined the trend of variations of barrier characteristics (barrier height and its position) as well as fusion cross sections for 50 isotopic systems including various collisions of C, O, Mg, Si, S, Ca, Ar, Ti and Ni nuclei with $1\leq N/Z < 1.6$ condition for compound systems. The results of our studies reveal that the relationships between increase of barrier positions and decrease of barrier heights are both linear with increase of $N/Z$ ratio. Moreover, fusion cross sections also enhance linearly with increase of this ratio.Comment: 28 pages, 7 figures, 5 Table