Unlicensed Operation of IEEE 802.16: Coexistence with 802.11(A) in Shared Frequency Bands

IEEE 802.16 based wireless mesh networks (WMNs) are a promising broadband access solution to support flexibility, cost effectiveness and fast deployment of the fourth generation infrastructure based wireless networks. Reducing the time for channel establishment is critical for low latency/interactive Applications. According to IEEE 802.16 MAC protocol, there are three scheduling algorithms for assigning TDMA slots to each network node: centralized and distributed the distributed is further divided into two operational modes coordinated distributed and uncoordinated distributed. In coordinated distributed scheduling algorithm, network nodes have to transmit scheduling message in order to inform other nodes about their transfer schedule. In this paper a new approach is proposed to improve coordinated distributed scheduling efficiency in IEEE 802.16 mesh mode, with respect to three parameter Throughput, Average end to end delay and Normalized Overhead. For evaluating the proposed networks efficiency, several extensive simulations are performed in various network configurations and the most important system parameters which affect the network performance are analyzed

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COMPOUND FAULT DIAGNOSIS OF BEARINGS USING AN IMPROVED SPECTRAL KURTOSIS BY MAXIMUM CORRELATION KURTOSIS DECONVOLUTION (MCKD).

June-2020 - International Journal of Engineering Sciences & Research Technology ◽

10.29121/ijesrt.v9.i8.2020.8 ◽

2020 ◽

Vol 9 (8) ◽

pp. 66-72

Keyword(s):

Fault Diagnosis ◽

Resonance Frequency ◽

Background Noise ◽

Maximum Correlation ◽

Vibration Signals ◽

Filter Length ◽

Frequency Bands ◽

Noise Interference ◽

Spectral Kurtosis

This paper discusses the use of Maximum Correlation kurtosis deconvolution (MCKD) method as a pre-processor in fast spectral kurtosis (FSK) method in order to find the compound fault characteristics of the bearing, by enhancing the vibration signals. FSK only extracts the resonance bands which have maximum kurtosis value, but sometimes it might possible that faults occur in the resonance bands which has low kurtosis value, also the faulty signals missed due to noise interference. In order to overcome these limitations FSK used with MCKD, MCKD extracts various faults present in different resonance frequency bands; also detect the weak impact component, as MCKD also dealt with strong background noise. By obtaining the MCKD parameters like, filter length & deconvolution period, we can extract the compound fault feature characteristics.

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Dual Band Paper Substrate CPW Antenna for Wireless Applications

International Journal of Innovative Technology and Exploring Engineering - Special Issue ◽

10.35940/ijitee.i3121.0789s319 ◽

2019 ◽

Vol 8 (9S3) ◽

pp. 605-608

Keyword(s):

Reflection Coefficient ◽

Mobile Communication ◽

Coplanar Waveguide ◽

Dual Band ◽

Antenna Feed ◽

Paper Substrate ◽

Frequency Bands ◽

Wireless Applications

In this paper, a 15* 80 sized antenna is designed over a paper substrate to test its flexible properties. The proposed antenna feed by a grounded coplanar waveguide(GCPW) is stimulated and the measured results show the operating Dual Band of the antenna cover(3.34-3.62 GHz) and (5.92-6.24 GHz) with the reflection coefficient |S11|< -15dB.These frequency bands operate over SHF bands and hence supports Fixed Mobile Communication and WLAN applications.

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Subject-Independent Classification of Japanese Spoken Sentences by Multiple Frequency Bands Phase Pattern of EEG Response During Speech Perception

10.21437/interspeech.2017-854 ◽

2017 ◽

Cited By ~ 1

Author(s):

Hiroki Watanabe ◽

Hiroki Tanaka ◽

Sakriani Sakti ◽

Satoshi Nakamura

Keyword(s):

Speech Perception ◽

Multiple Frequency ◽

Phase Pattern ◽

Frequency Bands

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Terahertz Radiators Based on Si~3C-SiC MQW IMPATT Diodes

Nanoscience &Nanotechnology-Asia ◽

10.2174/2210681209666190807154014 ◽

2020 ◽

Vol 10 (4) ◽

pp. 501-506

Author(s):

Monisha Ghosh ◽

Arindam Biswas ◽

Aritra Acharyya

Keyword(s):

High Frequency ◽

Multiple Quantum Well ◽

Multiple Quantum ◽

Noise Performance ◽

Rf Power ◽

Drift Diffusion ◽

Frequency Bands ◽

Atmospheric Window ◽

Lower Noise ◽

Impatt Diodes

Aims:: The potentiality of Multiple Quantum Well (MQW) Impacts Avalanche Transit Time (IMPATT) diodes based on Si~3C-SiC heterostructures as possible terahertz radiators have been explored in this paper. Objective:: The static, high frequency and noise performance of MQW devices operating at 94, 140, and 220 GHz atmospheric window frequencies, as well as 0.30 and 0.50 THz frequency bands, have been studied in this paper. Methods: The simulation methods based on a Self-Consistent Quantum Drift-Diffusion (SCQDD) model developed by the authors have been used for the above-mentioned studies. Results: Thus the noise performance of MQW DDRs will be obviously better as compared to the flat Si DDRs operating at different mm-wave and THz frequencies. Conclusion:: Simulation results show that Si~3C-SiC MQW IMPATT sources are capable of providing considerably higher RF power output with the significantly lower noise level at both millimeter-wave (mm-wave) and terahertz (THz) frequency bands as compared to conventional flat Si IMPATT sources.

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