Fast Implementation of Transmit Beamforming for Colocated MIMO Radar

Multiple-input Multiple-output (MIMO) radars benefit from spatial and waveform diversities to improve the performance potential. Phased array radars transmit scaled versions of a single waveform thereby limiting the transmit degrees of freedom to one. However MIMO radars transmit diverse waveforms from different transmit array elements thereby increasing the degrees of freedom to form flexible transmit beampatterns. The transmit beampattern of a colocated MIMO radar depends on the zero-lag correlation matrix of different transmit waveforms. Many solutions have been developed for designing the signal correlation matrix to achieve a desired transmit beampattern based on optimization algorithms in the literature. In this paper, a fast algorithm for designing the correlation matrix of the transmit waveforms is developed that allows the next generation radars to form flexible beampatterns in real-time. An efficient method for sidelobe control with negligible increase in mainlobe width is also presented

All fiber polarization insensitive detection for spectrometer based optical coherence tomography using optical switch

Polarization dependent image artifacts are common in optical coherence tomography imaging. Polarization insensitive detection scheme for swept source based optical coherence tomography systems is well established but is yet to be demonstrated for all fiber spectrometer-based Fourier domain optical coherence tomography systems. In this work, we present an all fiber polarization insensitive detection scheme for spectrometer based optical coherence tomography systems. Images from chicken breast muscle tissue were acquired to demonstrate the effectiveness of this scheme for the conventional Fourier domain optical coherence tomography system

Groundwater research and management: integrating science into management decisions. Proceedings of IWMI-ITP-NIH International Workshop on "Creating Synergy Between Groundwater Research and Management in South and Southeast Asia," Roorkee, India, 8-9 February 2005

Groundwater management / Governance / Groundwater development / Artificial recharge / Water quality / Aquifers / Groundwater irrigation / Water balance / Simulation models / Watershed management / Water harvesting / Decision making / South East Asia / Bangladesh / China / India / Nepal / Pakistan / Syria

Agricultural growth and structural changes in the Punjab economy: an input-output analysis

Agriculture Economic aspects India Punjab., Punjab (India) Economic conditions., Input-output analysis India Punjab.,

Groundwater externalities of surface irrigation transfers under National River Linking Project: Polavaram – Vijayawada link

River basin managementRiver basin developmentDevelopment projectsWater transferIrrigation canalsGroundwater irrigationTube well irrigationRiceSurface irrigationCrop managementSoil salinityWaterlogging

The lower Krishna Basin trajectory: relationships between basin development and downstream environmental degradation

River basin development / Lakes / Environmental degradation / Ecosystems / Mangroves / Water allocation / Groundwater / Water quality / Salinity / Irrigated farming / Institutions / Irrigation canals / Rural development

Unified equation of state for neutron stars on a microscopic basis

We derive a new equation of state (EoS) for neutron stars (NS) from the outer crust to the core based on modern microscopic Brueckner-Hartree-Fock (BHF) calculations using the Argonne $v_{18}$ potential plus three-body forces computed with the Urbana model. To deal with the inhomogeneous structures of matter in the NS crust, we use the recent Barcelona-Catania-Paris-Madrid (BCPM) nuclear energy density functional that is directly based on the same microscopic BHF calculations, and which is able to reproduce the ground-state properties of nuclei along the periodic table. The EoS of the outer crust requires the masses of neutron-rich nuclei, which are obtained through Hartree-Fock-Bogoliubov calculations with the BCPM functional when they are unknown experimentally. To compute the inner crust, Thomas-Fermi calculations in Wigner-Seitz cells are performed with the same functional. Existence of nuclear pasta is predicted in a range of average baryon densities between $\simeq$0.067 fm$^{-3}$ and $\simeq$0.0825 fm$^{-3}$, where the transition to the core takes place. The NS core is computed from the nuclear EoS of the BHF calculation assuming non-exotic constituents (core of $npe\mu$ matter). In each region of the star, we discuss the comparison of the new EoS with previous EoSes for the complete NS structure, in particular, with the Lattimer-Swesty EoS and with the Shen et al. EoS widely used in astrophysical calculations. The new microscopically derived EoS fulfills at the same time a NS maximum mass of 2~$M_\odot$ with a radius of 10 km, and a 1.5~$M_\odot$ NS with a radius of 11.7 km.Comment: 23 pages, 17 figures, revised version accepted for publication in Astronomy & Astrophysic

Area Efficient Level Sensitive Flip-Flops – A Performance Comparison

Due to increased demand of portable and battery operated devices, ultra-low power and high speed devices with less area requirement are important nowadays. Latch is the basic element for all the sequential circuits. This paper presents comparison of various circuits of D latch on the basis of power consumption, area efficiency and delay. Basically in these latches transmission gates are replaced by pass transistors to reduce the transistor count. Comparison results indicate that latch design with least transistor count is the best choice for portable applications. Keywords: area efficient, latch, sub-threshold region, pass transistor, low power, level sensitive flip-flops, flip-flops

Wallace Tree Multiplier Designs: A Performance Comparison Review

Multiplication process is often used in digital signal processing systems, microprocessors designs, communication systems, and other application specific integrated circuits. Multipliers are complex units and play an important role in deciding the overall area, speed and power consumption of digital designs. This paper presents a comparison review of various Wallace tree multiplier designs in terms of parameters like latency, complexity and power consumption. Keywords: Booth Recoding Algorithm, Carry Look Ahead Adder, Carry Select Adder, Compressors, Ripple Carry Adder, Sklansky Adder, Wallace Tree Multipliers