Joint precoder and window design for OFDM sidelobe suppression

Spectral precoding and windowing are two effective approaches to reduce out-of-band radiation (OBR) in multicarrier systems. Their performance comes at the price of reduced throughput and additional computational complexity, so there is strong motivation for simultaneously using both techniques. We present a novel design that jointly optimizes the precoder and window coefficients to minimize radiated power within a user-selectable frequency region. Results show that the proposed design achieves a better OBR/throughput/complexity tradeoff than either of these individual techniques separately.Agencia Estatal de Investigación | Ref. BES-2017-080305Agencia Estatal de Investigación | Ref. PID2019-105717RB-C21Agencia Estatal de Investigación | Ref. PID2019-105717RB-C2

Mask-compliant orthogonal precoding for spectrally efficient OFDM

Orthogonal precoding constitutes a powerful technique to reduce spectrum sidelobes of multicarrier signals. This reduction is bought at the cost of introducing precoder redundancy, which results in some throughput loss and additional precoding/decoding complexity. When the goal is to meet some spectral emission mask constraints, it is desirable to avoid unnecessary sidelobe suppression in order to keep precoder redundancy at a minimum. In this context, we introduce a general framework under which we develop a novel Lagrange multiplier-based mask-compliant orthogonal precoder design targeting minimal redundancy. We also adapt to this framework two previously proposed designs based on spectral notches and minimum out-of-band emission, respectively, to explicitly incorporate mask constraints. Simulation results are provided to show the effectiveness of the proposed designs under different practical masks for multicarrier wireless systems.Agencia Estatal de Investigación | Ref. TEC2016-76409-C2-2-RAgencia Estatal de Investigación | Ref. BES-2017-080305Agencia Estatal de Investigación | Ref. PID2019-105717RB-C21Xunta de Galici

Innovative Behaviour Mediates in the Relationship between Employee Creativity and Organisational Innovation

The telecommunications industries play a vital role in enhancing Malaysia’s innovation level. In this perspective, telecommunications industries need innovative human resources development. Therefore, the study attempts to examine the effect of employee creativity (EC) on organisational innovation (OI) through the mediating role of innovative behaviour (IB). A quantitative study was conducted by survey questionnaires to the employees of telecommunications industries in Malaysia. In addition, structural equation modelling (SEM) is used to determine the effect of employee creativity on organisational innovation through the mediating role of innovative behaviour with the support of the componential theory of organisational creativity and innovation. Finally, the results found that innovative behaviour significantly mediated in the relationship between employee creativity and organisational innovation. Thus, the research study has had a beneficial effect on innovation in the telecommunications industries in Malaysia

The Dynamics of Language in National Perspective: Can We Ignore Lingua Franca?

Language is not only a means of communication but also provides basis for developing and sustaining cultures and values. Historical evidences proved the effects of language on social, culture, economic, politics, society and education. History also revealed that the language of the conquerors became a common language for captors. This phenomenon still exists, the role of language in national development is inevitable and thus language is considered as foundation for a nation. Taking into account the role of language, this review paper which is grounded in theory provides a deep insight to study the above mentioned factors which contributed in transforming societies with a particular focus on Pakistani context. Next, this paper highlighted the role of national language and will discuss the related controversy. English and Urdu are declared as official languages and the nation is still perplexed to solve this issue. There is a strong social pressure that Urdu should be prioritized but this dream could not turn into reality yet. On the other hand, English as being an international language cannot be ignored for the sake of achieving international goals and standards.</p

Ecosystem Approach and Hydrological Potential Study of Port Qasim Industrial Coastal Zone of Karachi Pakistan

Extensive excavations for groundwater and rainfall diminish during past decades have disturbed water balance of Sindh Est extending over area between Indus and Kirthar Range towards west from District Dadu to the Coastal Zone and Indus Delta in the south. Groundwater exploitation without is determining hydrological potential of the region. This has increased the risk of seawater intrusion and of seismic events in the coastal areas.Groundwater depletion has been caused by the loss of infiltration capacity of surface soil due to sealing of top soil resulting from construction activities in urban areas and to salinization of soil in the canal command rural areas; both processes being responsible for reducing the capacity to recharge the groundwater aquifers. Excavation of silt, sand and gravel from bed of river and natural channels for construction activities in the urban areas of western Sindh has reduced the absorption capacity. Environmental Profile has discussed. Surface water, groundwater and wastewater, waste stream being discharged into the river and seawater along the coast has been determined with respect to several physical, chemical and biological parameters. For environmental hazards protection and handling of oil and molasses, PQA has adopted Environmental Management Plan. That was capable to avoid certain type of eco-disasters. Manage all environmental disasters and also including oil spill at KE Bin Qasim and PSO pumping station. Keywords: Groundwater, sea water intrusion, salinization of soil, environmental hazards, environmental management pla

3-(4-Bromo­phenyl­sulfon­yl)-8-methyl-1,3-diaza­spiro­[4.5]decane-2,4-dione

The crystal structure of the title compound, C15H17BrN2O4S, is stabilized by inter­molecular N—H⋯O hydrogen bonds which link the mol­ecules into centrosymmetric dimers. The dihedral angle subtended by the 4-bromo­phenyl group with the mean plane passing through the hydantoin unit is 83.29 (5)°. The cyclo­hexyl group adopts an ideal chair conformation with the methyl group in an equatorial position

3-(4-Chloro­phenyl­sulfon­yl)-8-methyl-1,3-diaza­spiro­[4.5]decane-2,4-dione

In the title compound, C15H17ClN2O4S, the atoms in the hydantoin ring are coplanar (r.m.s. deviation = 0.006 Å). The crystal structure is stabilized by inter­molecular N—H⋯O hydrogen bonds which link the mol­ecules into centrosymmetric dimers. The dihedral angle subtended by the 4-chloro­phenyl group with the plane passing through the hydantoin unit is 82.98 (4)°. The cyclo­hexyl ring adopts an ideal chair conformation