466 research outputs found
Localization of DOA trajectories -- Beyond the grid
The direction of arrival (DOA) estimation algorithms are crucial in
localizing acoustic sources. Traditional localization methods rely on
block-level processing to extract the directional information from multiple
measurements processed together. However, these methods assume that DOA remains
constant throughout the block, which may not be true in practical scenarios.
Also, the performance of localization methods is limited when the true
parameters do not lie on the parameter search grid. In this paper we propose
two trajectory models, namely the polynomial and bandlimited trajectory models,
to capture the DOA dynamics. To estimate trajectory parameters, we adopt two
gridless algorithms: i) Sliding Frank-Wolfe (SFW), which solves the Beurling
LASSO problem and ii) Newtonized Orthogonal Matching Pursuit (NOMP), which
improves over OMP using cyclic refinement. Furthermore, we extend our analysis
to include wideband processing. The simulation results indicate that the
proposed trajectory localization algorithms exhibit improved performance
compared to grid-based methods in terms of resolution, robustness to noise, and
computational efficiency
Parameter extraction of Extended Floating Gate Field Effect Transistors (EGFETs): Estimating the threshold voltage, series resistance, and mobility degradation from I-V measurements
Extended Floating Gate Field Effect Transistors (EGFETs) are CMOS-compatible
floating gate devices capable of detecting charges on their sensing area by the
relative shifts in current-voltage (I-V) characteristics. The I-V shifts are
generally computed by measuring the EGFET parameters in the strong inversion
region of operation. This could lead to errors in estimating the device
sensitivity because the simple I-V model ignores the mobility degradation and
series resistance effects in EGFETs. Our goal is to model these parasitic
effects and present methods to extract the key device parameters. We derive an
analytical I-V model for EGFETs in the linear region of transistor operation,
accounting for both the mobility degradation and series resistance effects.
Based on the analytical model, three methods are presented to estimate the key
parameters, namely the threshold voltage, series resistance, surface roughness
parameter, low-field mobility, and effective mobility from the I-V
characteristics, gate transconductance, and drain conductance. The peak
transconductance method is used as a benchmark for comparing the extracted
threshold voltages. Silicon-based EGFET devices are fabricated, and their I-V
characteristics are measured with deionized water and three polyelectrolytes.
From the I-V data, the parameter extraction methods are used to compute the
values of the key parameters, and the suitability of each method is discussed.
The gate transconductance methods show good agreement between the values for
the key parameters, while the drain transconductance method gives lower values
of the key parameters. There is scope to improve the presented methods by
incorporating the effects of substrate bias and asymmetric series resistance
for new extended-gate device architectures, including solution-based organic
field-effect transistors.Comment: 19 pages, 8 figures, preprin
Random Matrix Model for Nakagami-Hoyt Fading
Random matrix model for the Nakagami-q (Hoyt) fading in multiple-input
multiple-output (MIMO) communication channels with arbitrary number of
transmitting and receiving antennas is considered. The joint probability
density for the eigenvalues of H{\dag}H (or HH{\dag}), where H is the channel
matrix, is shown to correspond to the Laguerre crossover ensemble of random
matrices and is given in terms of a Pfaffian. Exact expression for the marginal
density of eigenvalues is obtained as a series consisting of associated
Laguerre polynomials. This is used to study the effect of fading on the Shannon
channel capacity. Exact expressions for higher order density correlation
functions are also given which can be used to study the distribution of channel
capacity.Comment: 11 pages, 4 figure
AUGMENTED REALITY BASED USER GUIDANCE FOR OPTIMAL COLLABORATION EXPERIENCE IN A WIFI NETWORK
Techniques are described herein for recommending locations to users that are close to them based on the users\u27 current application requirement and current network conditions. Augmented Reality (AR) is then used to guide the user towards an area of good service. Metadata is shared back with a network controller for future requirements and guidance of other users
WAKE UP RADIO PROTECTION FROM DENIAL OF SERVICE ATTACK BASED ON BASEBAND MONITORING
A malicious attacker can drain the batteries of Internet of Things (IoT) devices by sending many wake up radio (WUR) transmissions. Accordingly, techniques are provided herein to enable an Access Point (AP) to detect any malicious WUR requests. The AP may intelligently mitigate the attack with the help of the stations (STAs)
Rhabdomyolysis and myopericarditis with renal failure in a patient of status epilepticus
Rhabdomyolysis is characterized by the destruction and leakage of muscle cell components into the circulation. Sustained and prolonged muscle activity is an important factor causing the same. Most of the reported cases in the literature were due to status epilepticus. We report the case of a 25-year-old male who developed acute renal failure and myopericarditis in association with non-traumatic rhabdomyolysis following status epilepticus
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