7 research outputs found

    Relay beamforming to mitigate inter-relay interference in multi-cell scenario

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    In relay assisted Long Term Evolution-Advanced (LTE-A) network, enhanced Node B (eNB) autonomously selects different backhaul sub-frame configurations to adopt traffic variations, which might cause inter-relay interference (IRI) between relay nodes (RNs) in adjacent cells. IRI can happen due to asynchronous transmission between adjacent cells, which results in IRI from the access link to the backhaul link of adjacent relay in the downlink direction and vice versa. This causes severe loss in system capacity and introduces high outage probability. In this article, we consider the IRI problem in a multi-cell relaying system. Previous studies consider the beamforming design for cooperative relay network as a single-cell problem, without taking into account the occurrence of IRI. However, the performance of the RN assisted network is limited by the IRI from adjacent RN. A hybrid zero-forcing and singular value decomposition (ZF-SVD) beamforming technique is proposed to eliminate the IRI. Simulation results show that the proposed scheme out-performs the comparable scheme in both the ergodic capacity and outage probability

    Using amplify-and-forward relay for coverage extension in indoor environments

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    Cooperative communication is a promising method for increasing the capacity and extending the coverage between a base station (BS) and a mobile user (MU) by using relays to exploit cooperative diversity. However, the existing literature mainly focuses on theoretical performance evaluation without experimental validation and, thus, fails to address the effects on real-world radio signal propagation. This research, therefore, aims to develop a prototype amplify-and-forward (AF) relay using software-defined radio (SDR) to evaluate the real-world performance of such a relay in improving coverage. The proposed relay is developed using the LabVIEW software and programmed on a National Instruments-Universal Software Radio Peripheral 2922 (NI-USRP 2922) SDR platform. The major merit of this entire communication setup is less expensive as the system uses a reprogrammable hardware. The measurements are performed indoors, and the signal strength or received power at the MU in cases with and without the relay is recorded. The results show that the received power performance and signal-to-noise ratio (SNR) at the user improve significantly when the AF relay is deployed compared to when direct link point-to-point transmission without the relay is used

    Monoallelic and bi-allelic variants in NCDN cause neurodevelopmental delay, intellectual disability, and epilepsy

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    Neurochondrin (NCDN) is a cytoplasmatic neural protein of importance for neural growth, glutamate receptor (mGluR) signaling, and synaptic plasticity. Conditional loss of Ncdn in mice neural tissue causes depressive-like behaviors, impaired spatial learning, and epileptic seizures. We report on NCDN missense variants in six affected individuals with variable degrees of developmental delay, intellectual disability (ID), and seizures. Three siblings were found homozygous for a NCDN missense variant, whereas another three unrelated individuals carried different de novo missense variants in NCDN. We assayed the missense variants for their capability to rescue impaired neurite formation in human neuroblastoma (SH-SY5Y) cells depleted of NCDN. Overexpression of wild-type NCDN rescued the neurite-phenotype in contrast to expression of NCDN containing the variants of affected individuals. Two missense variants, associated with severe neurodevelopmental features and epilepsy, were unable to restore mGluR5-induced ERK phosphorylation. Electrophysiological analysis of SH-SY5Y cells depleted of NCDN exhibited altered membrane potential and impaired action potentials at repolarization, suggesting NCDN to be required for normal biophysical properties. Using available transcriptome data from human fetal cortex, we show that NCDN is highly expressed in maturing excitatory neurons. In combination, our data provide evidence that bi-allelic and de novo variants in NCDN cause a clinically variable form of neurodevelopmental delay and epilepsy, highlighting a critical role for NCDN in human brain development

    From RFLP to DArT: molecular tools for wheat (Triticum spp.) diversity analysis

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    Wheat (Triticum spp.) is a universally lucrative agricultural crop. An increase in wheat production has been shown through selection by the farmers which can increase the grain profitability. The determination of genetic associations among domestic cultivars is facilitated by molecular markers. Data on genetic polymorphism is valuable for the germplasm association and regarding the developing management strategies. The information would be supportive for potential genome mapping programs and for the relevance of intellectual property rights of wheat breeders. Present review is an effort for providing support information to wheat breeders to develop varieties with varied genetic environment to attain continuity in large-scale wheat production. In this review, we have tried to provide a collective depiction of relevant information about the usage of some commonly used markers in wheat. It may help researchers to find out the frequentness and application of different markers and compare their results. The manuscript may serve as a platform helping the intellectuals for the selection and modification of their marker system in wheat diversity analysis. The heart of this review is the emphasis on the performance of various molecular genetic markers in diversity studies in relation to definite approaches that are in practice since several years allied with the multifaceted wheat molecular breeding and its polyploid nature
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