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We introduce QUANTISENC, a fully configurable open-source software-defined digital quantized spiking neural core architecture to advance research in neuromorphic computing. QUANTISENC is designed hierarchically using a bottom-up methodology with multiple neurons in each layer and multiple layers in each core. The number of layers and neurons per layer can be configured via software in a top-down methodology to generate the hardware for a target spiking neural network (SNN) model. QUANTISENC uses leaky integrate and fire neurons (LIF) and current-based excitatory and inhibitory synapses (CUBA). The nonlinear dynamics of a neuron can be configured at run-time via programming its internal control registers. Each neuron performs signed fixed-point arithmetic with user-defined quantization and decimal precision. QUANTISENC supports all-to-all, one-to-one, and Gaussian connections between layers. Its hardware-software interface is integrated with a PyTorch-based SNN simulator. This integration allows to define and train an SNN model in PyTorch and evaluate the hardware performance (e.g., area, power, latency, and throughput) through FPGA prototyping and ASIC design. The hardware-software interface also takes advantage of the layer-based architecture and distributed memory organization of QUANTISENC to enable pipelining by overlapping computations on streaming data. Overall, the proposed software-defined hardware design methodology offers flexibility similar to that of high-level synthesis (HLS), but provides better hardware performance with zero hardware development effort. We evaluate QUANTISENC using three spiking datasets and show its superior performance against state-of the-art designs.

The advantage of computational resources in edge computing near the data source has kindled growing interest in delay-sensitive Internet of Things (IoT) applications. However, the benefit of the edge server is limited by the uploading and downloading links between end-users and edge servers when these end-users seek computational resources from edge servers. The scenario becomes more severe when the user-end's devices are in the shaded region resulting in low uplink/downlink quality. In this paper, we consider a reconfigurable intelligent surface (RIS)-assisted edge computing system, where the benefits of RIS are exploited to improve the uploading transmission rate. We further aim to minimize the delay of worst-case in the network when the end-users either compute task data in their local CPU or offload task data to the edge server. Next, we optimize the uploading bandwidth allocation for every end-user's task data to minimize the maximum delay in the network. The above optimization problem is formulated as quadratically constrained quadratic programming. Afterward, we solve this problem by semidefinite relaxation. Finally, the simulation results demonstrate that the proposed strategy is scalable under various network settings., Comment: 6 pages, 3 figures, accepted for publication in IEEE GLOBECOM 2021

A new class of sensing paradigm known as lab-onskin where stretchable and flexible smart sensor devices are integrated into the skin, provides direct monitoring and diagnostic interfaces to the body. Distributed lab-on-skin wireless sensors have the ability to provide continuous long term assessment of the skin health. This paper proposes a distributed skin health monitoring system using a wireless body area network. The system is responsive to the dynamic changes in the skin health, and remotely reports on the same. The proposed algorithm detects the abnormal skin and creates an energy efficient data aggregation tree covering the affected area while putting the unnecessary sensors to sleep mode. The algorithm responds to the changing conditions of the skin by dynamically adapting the size and shape of the monitoring trees to that of the abnormal skin areas thus providing a comprehensive monitoring. Simulation results demonstrate the application and utility of the proposed algorithm for changing wound shapes and sizes.

In this paper, we derive the error vector magnitude (EVM) in a selection combining (SC) system experiencing co-channel interference, for arbitrary number of antennas and interferers when all the channels experience Rayleigh fading. We use a novel approach that uses the CCDF of SIR to derive EVM as using the conventional approach to derive EVM for a SC system is difficult. Considering two selection rules based on (a) maximum signal power (b) maximum signal to interference ratio, we observe that EVM is worse when maximum signal power based rule is used. Further, EVM is also derived considering (a) all the channels to be independent and (b) channels to be correlated due to insufficient antenna spacing at receiver. For some special cases, EVM is also derived when the desired channels experience Nakagami-m fading.

World wide road traffic fatality and accident rates are high, and this is true even in technologically advanced countries like the USA. Despite the advances in Intelligent Transportation Systems, safe transportation routing i.e., finding safest routes is largely an overlooked paradigm. In recent years, large amount of traffic data has been produced by people, Internet of Vehicles and Internet of Things (IoT). Also, thanks to advances in cloud computing and proliferation of mobile communication technologies, it is now possible to perform analysis on vast amount of generated data (crowd sourced) and deliver the result back to users in real time. This paper proposes SafeRNet, a safe route computation framework which takes advantage of these technologies to analyze streaming traffic data and historical data to effectively infer safe routes and deliver them back to users in real time. SafeRNet utilizes Bayesian network to formulate safe route model. Furthermore, a case study is presented to demonstrate the effectiveness of our approach using real traffic data. SafeRNet intends to improve drivers safety in a modern technology rich transportation system., Comment: Paper was accepted at the 14th IEEE Consumer Communications & Networking Conference (CCNC 2017)

The $\kappa$-$\mu$ shadowed fading model is a very general fading model as it includes both $\kappa$-$\mu$ and $\eta$-$\mu$ as special cases. In this work, we derive the expression for outage probability when the signal-of-interest (SoI) and interferers both experience $\kappa$-$\mu$ shadowed fading in an interference limited scenario. The derived expression is valid for arbitrary SoI parameters, arbitrary $\kappa$ and $\mu$ parameters for all interferers and any value of the parameter $m$ for the interferers excepting the limiting value of $m\rightarrow \infty$. The expression can be expressed in terms of Pochhammer integral where the integrands of integral only contains elementary functions. The outage probability expression is then simplified for various special cases, especially when SoI experiences $\eta$-$\mu$ or $\kappa$-$\mu$ fading. Further, the rate expression is derived when the SoI experiences $\kappa$-$\mu$ shadowed fading with integer values of $\mu$, and interferers experience $\kappa$-$\mu$ shadowed fading with arbitrary parameters. The rate expression can be expressed in terms of sum of Lauricella's function of the fourth kind. The utility of our results is demonstrated by using the derived expression to study and compare FFR and SFR in the presence of $\kappa$-$\mu$ shadowed fading. Extensive simulation results are provided and these further validate our theoretical results.

When the user channel experiences Nakagami-m fading, the coverage probability expressions are theoretically compared for the following cases: (i). The N interferers are independent $\eta$-$\mu$ random variables (RVs). (ii). The N interferers are correlated $\eta$-$\mu$ RVs. It is analytically shown that the coverage probability in the presence of correlated interferers is greater than or equal to the coverage probability in the presence of independent interferers when the shape parameter of the channel between the user and its base station (BS) is not greater than one. Further, rate is compared for the following cases: (i). The user channel experiences $\eta$-$\mu$ RV and the $N$ interferers are independent $\eta$-$\mu$ RVs. (ii). The N interferers are correlated $\eta$-$\mu$ RVs. It is analytically shown that the rate in the presence of correlated interferers is greater than or equal to the rate in the presence of independent interferers. Simulation results are provided and these match with the obtained theoretical results. The utility of our results are also discussed., Comment: This is a significantly expanded version of our paper arXiv:1401.4663

In this paper, we derive the data-aided Error Vector Magnitude (EVM) in an interference limited system when both the desired signal and interferers experience independent and non identically distributed $\kappa$-$\mu$ shadowed fading. Then it is analytically shown that the EVM is equal to the square root of number of interferers when the desired signal and interferers do not experience fading. Further, EVM is derived in the presence of interference and noise, when the desired signal experiences $\kappa$-$\mu$ shadowed fading and the interferers experience independent and identical Nakagami fading. Moreover, using the properties of the special functions, the derived EVM expressions are also simplified for various special cases.

We present a detailed V-band photometric light curve modeling of 30 eclipsing binaries using the data from Pietrukowicz et al. (2009) collected with the European Southern Observatory Very Large Telescope (ESO VLT) of diameter 8-m. The light curve of these 30 eclipsing binaries were selected out of 148 of them available in the database on the basis of complete phase coverage, regular and smooth phased light curve shapes. Eclipsing binaries play pivotal role in the direct measurement of astronomical distances more accurately simply from their geometry of light curves. The accurate value of Hubble constant (H0) which measures the rate of expansion of the Universe heavily relies on extragalactic distance scale measurements. Classification of the selected binary stars in the sample were done, preliminarily on the basis of Fourier parameters in the a2-a4 plane and final classification was obtained from the Roche lobe geometry. Out of these 30 eclipsing binaries, only one was found to be detached binary system while the rest 29 of them belong to the contact binary systems. These contact binaries were further classified into the A-type and W-type based on their mass ratios. Since spectroscopic mass ratio measurements were not available for any of these binary stars, we determined the mass ratios through photometric light curve modeling with the aid of Wilson-Devinney code as implemented in PHOEBE. Various geometrical parameters and physical parameters of astrophysical importance viz., mass, radius and luminosity were obtained from the light curves of the selected stars., Comment: 19 pages, 6 figures, 7 tables. Accepted for publication in DU Journal of Undergraduate Research and Innovation (DUJURI) http://journals.du.ac.in/ugresearch/

In this work, we analytically study the impact of spectrum allocation scheme in picocells on the coverage probability (CP) of the Pico User (PU), when the macro base stations (MBSs) employ either fractional frequency reuse (FFR) or soft frequency reuse (SFR). Assuming a fixed size for the picocell, the CP expression is derived for a PU present in either a FFR or SFR based deployment, and when the PU uses either the centre or the edge frequency resources. Based on these expressions, we propose two possible frequency allocation schemes for the picocell when FFR is employed by the macrocell. The CP and the average rate expressions for both these schemes are derived, and it is shown that these schemes outperform the conventional scheme where no inter-cell interference coordination (ICIC) is assumed. The impact of both schemes on the macro-user performance is also analysed. When SFR is used by the MBS, it is shown that the CP is maximized when the PU uses the same frequency resources as used by the centre region., Comment: Submitted to IEEE TRANSACTIONS ON VEHICULAR TECHNOLOGY

Fractional frequency reuse (FFR) is an inter-cell interference coordination scheme that is being actively researched for emerging wireless cellular networks. In this work, we consider hexagonal tessellation based planned FFR deployments, and derive expressions for the coverage probability and normalized average rate for the downlink. In particular, given reuse $\frac{1}{3}$ (FR$3$ ) and reuse $1$ (FR$1$) regions, and a Signal-to-Interference-plus-noise-Ratio (SINR) threshold $S_{th}$ which decides the user assignment to either the FR$1$ or FR$3$ regions, we theoretically show that: $(i)$ The optimal choice of $S_{th}$ which maximizes the coverage probability is $S_{th} = T$, where $T$ is the required target SINR (for ensuring coverage), and $(ii)$ The optimal choice of $S_{th}$ which maximizes the normalized average rate is given by the expression $S_{th}=\max(T, T')$, where $T'$ is a function of the path loss exponent and the fade parameters. For the optimal choice of $S_{th}$, we show that FFR gives a higher rate than FR$1$ and a better coverage probability than FR$3$. The impact of frequency correlation over the sub-bands allocated to the FR$1$ and FR$3$ regions is analysed, and it is shown that correlation decreases the average rate of the FFR network. Numerical results are provided, and these match with the analytical results., Comment: Submitted to: IEEE Transactions on Communications

Coverage probability and rate expressions are theoretically compared for the following cases: $(i).$ Both the user channel and the $N$ interferers are independent and non identical Nakagami-m distributed random variables (RVs). $(ii).$ The $N$ interferers are correlated Nakagami-m RVs. It is analytically shown that the coverage probability in the presence of correlated interferers is greater than or equal to the coverage probability in the presence of non-identical independent interferers when the shape parameter of the channel between the user and its base station is not greater than one. It is further analytically shown that the average rate in the presence of correlated interferers is greater than or equal to the average rate in the presence of non-identical independent interferers. Simulation results are provided and these match with the obtained theoretical results. The utility of our results are also discussed.

Uplink power control plays a key role on the performance of uplink cellular network. In this work, the power control factor ($\in[0,1]$) is evaluated based on three parameters namely: average transmit power, coverage probability and average rate. In other words, we evaluate power control factor such that average transmit power should be low, coverage probability of cell-edge users should be high and also average rate over all the uplink users should be high. We show through numerical studies that the power control factor should be close to $0.5$ in order to achieve an acceptable trade-off between these three parameters., Comment: arXiv admin note: text overlap with arXiv:1203.1304 by other authors