Design of Simulation for Time-Division Multiplexing Digital Optimal Frequency Band Transmission System

This paper designs a simulation experiment model of the overall structure of time-division multiplexing digital optimal frequency band transmission system based on MATLAB simulation platform. The parameters of each module in the simulation model are set. The working process and performance of the time-division multiplexing digital optimal band transmission system are simulated. The simulation results show that the digital optimal band transmission system achieves the best transmission receiving conditions and performance, and the designed time-division multiplexing optimal digital band transmission simulation system achieves its functions. The research in this paper will help to improve the level of digital communication technology and to understand the structure of time-division multiplexing digital optimal band transmission system.

Experimental Study on Split-Ring Resonators with Different Slit Widths

Metamaterial one-dimensional periodic structures are composed of split-ring resonators, which can display electric permittivity and magnetic permeability simultaneously negative, are studied experimentally. In the present study, each resonator is made up of two concentric circular copper rings patterned on a substrate of kapton, with slits diametrically opposite each other and with the line of the splits along the longitudinal direction of the periodic array containing seven split rings evenly spaced. The experiments consist in inserting the metamaterial slab into a square waveguide of side length 6 mm, corresponding to a cutoff frequency of 25 GHz. Transmission bands due to magnetic and electrical responses are identified for slits with aperture widths of 1 mm and 2 mm, centered at 5.67 and 6.12 GHz frequencies, respectively, values well below the 25 GHz frequency cutoff, so characterizing a medium with negative permeability and permittivity.

Alcohol Sensing Over O＋E＋S＋C＋L＋U Transmission Band Based on Porous Cored Octagonal Photonic Crystal Fiber

A micro structure porous cored octagonal photonic crystal fiber （P-OPCF） has been proposed to sense aqueous analysts （alcohol series） over a wavelength range of 0.80 μm to 2.0 μm. By implementing a full vectorial finite element method （FEM）, the numerical simulation on the proposed O-PCF has been analyzed. Numerical investigation shows that high sensitivity can be gained by changing the structural parameters. The obtained result shows the sensitivities of 66.78%, 67.66%, 68.34%, 68.72%, and 69.09%, and the confinement losses of 2.42×10^-10 dB/m, 3.28x×10^-11 dB/m, 1.21 ×10^-6 dB/m, 4.79×10^-10 dB/m, and 4.99×10^-9 dB/m at the 1.33 ktm wavelength for methanol, ethanol, propanol, butanol, and pentanol, respectively can satisfy the condition of much legibility to install an optical system. The effects of the varying core and cladding diameters, pitch distance, operating wavelength, and effective refractive index are also reported here. It reflects that a significant sensitivity and low confinement loss can be achieved by the proposed P-OPCE The proposed P-OPCF also covers the wavelength band （O＋E＋S＋C＋L＋U）. The investigation also exhibits that the sensitivity increases when the wavelength increases like SO-band〈SE-band 〈SS-band 〈 SC-band 〈SL-band 〈SU-band. This research observation has much pellucidity which has remarkable impact on the field of optical fiber sensor.

Design of a Porous Cored Hexagonal Photonic Crystal Fiber Based Optical Sensor With High Relative Sensitivity for Lower Operating Wavelength

In this article, highly sensitive and low confinement loss enriching micro structured photonic crystal fiber （PCF） has been suggested as an optical sensor. The proposed PCF is porous cored hexagonal （P-HPCF） where cladding contains five layers with circular air holes and core vicinity is formed by two layered elliptical air holes. Two fundamental propagation characteristics such as the relative sensitivity and confinement loss of the proposed P-HPCF have been numerically scrutinized by the full vectorial finite element method （FEM） simulation procedure. The optimized values are modified with different geometrical parameters like diameters of circular or elliptical air holes, pitches of the core, and cladding region over a spacious assortment of wavelength from 0.8 ktm to 1.8 -m. All pretending results exhibit that the relative sensitivity is enlarged according to decrement of wavelength of the transmission band （O＋E＋S＋C＋L＋U）. In addition, all useable liquids reveal the maximum sensitivity of 57.00%, 57.18%, and 57.27% for n=1.33, 1.354, and 1.366 respectively by lower band. Moreover, effective area, nonlinear coefficient, frequency, propagation constant, total electric energy, total magnetic energy, and wave number in free space of the proposed P-HPCF have been reported recently.