Papers by Keyword: Insertion Loss

Abstract: This study aimed to evaluate Fe₂O₃ based magnetic ferrite performance and its composition using Rare Earth Oxide (REO) of Yttrium as dopant and Gadolinium as co-dopant elements. Lot of specimens were prepared through dry pressing technique, and sintered into the high temperature tube furnace up to 1450°C. Sintering duration of 5 hours results the best magnetic properties. The existence of Gadolinium element tends to improve magnetic properties of magnetic ferrite Gd-doped YIG structure. Remacomp brand Magnet-Physik was used to determine the characteristics of soft magnetic materials in the measurement frequency range of 10 Hz to 70 kHz. Microwave response was measured using the Vector Network Analysis to provide insertion loss and isolation data. The obtained insertion loss of Gd_0.75Y_2.25Fe5O₁₂ is 0.4270 dB (at 3.7 GHz) and 0.2455 dB (at 4.2 GHz), while the isolation value is 11.3840 dB (at 3.7 GHz) and 17.8250 dB (at 4.2 GHz). The further experiment will be carried out to improve the microwave response and better magnetic properties of Gd-doped YIG structure.

Abstract: In order to reduce floor impact sound in apartment houses, 30 types of floor coverings were chosen to evaluate a performance of reduction in impact sound in the reverberation chamber. In the test of performance of reduction in impact sound using bang machine, a performance of impact sound reduction can be ensured at a low frequency band of 63 Hz and 100 Hz. However, impact sound was amplified at a band of 80 Hz and 125 Hz except for some floor coverings. In the test of performance of reduction in impact sound using a rubber ball drop at a height of 100 cm, a performance of reduction in impact sound was improved from a band of 50 Hz up to 400 Hz. In the test of rubber ball drop at a height of 40 cm, which was similar to the impact of children's running, a performance of reduction in impact sound was improved from a band of 80 Hz and 160 Hz up to 400 Hz.

Abstract: The design uses silicon-AlN thin films as the piezoelectric substrate, Use apo- dization weighting methods to optimize the design of IDT. The improved δ function model was Modeling Tools of Apodization weighted ellipse IDT structure, According to the result of simulation, we designed a layout of SAW band-pass filter and fabricated a sample of it which center frequency is 300MHz and insertion loss is 7dB, The research shows the consistency of simulation results with the experimental results.

Abstract: This do In this paper, based on the Wilkinson power divider, a modified Wilkinson power divider using a microstrip in isolation is discussed. It can reduces the size of the circuit board area. What’s more, the isolation bandwidth can be extend by the Wilkinson power divider using a microstrip in isolation. Firstly, this paper illustrates the principles of the traditional Wilkinson power divider. By introducing the concept of isolation network, the real and imaginary part of the traditional Wilkinson power divider are derived. And then, the principle diagram the Wilkinson power divider with RLC isolation network are shown, we also give the expression of the real part and imaginary part of the isolation network. Lastly, we introduce the modified Wilkinson power divider using a microstrip in isolation, and give the expressions of real part and imaginary part of the isolation network, and the above three kinds of real part and imaginary part of Wilkinson power divider are simulated. Through simulation, we found the power divider using a microstrip in isolation has better physical performance.

Abstract: Arrayed waveguide grating (AWG) is a very popular dense wavelength division multiplexing (DWDM) device, which is produced in the field of optical communication technology. Instead of traditional grating and lens spectral system, AWG is used as the spectral chip in miniature Raman spectrometer. It’s quite important for miniature Raman spectrometer in miniaturization and low cost. This paper analyzed the basic principles of AWG device, and introduces the insertion loss, crosstalk and phase error performance parameters, also focuses on the specific technical requirements about wavelength, optical channel number, phase error, wavelength resolution and bandwidth, which are applied in miniature Raman spectrometer. Some new researches and a series of related simulation have been made, finally won the 1 * 40 channels AWG spectral chips, with wavelength range of 880-920 nm, insertion loss of center wavelengths is better than-0.9 dB.

Abstract: The exhaust noise, which falls into low-frequency noise, is the dominant noise source of a diesel engines and tractors. The traditional exhaust silencers, which are normally constructed by combination of expansion chamber, and perforated pipe or perforated board, are with high exhaust resistance, but poor noise reduction especially for the low-frequency band noise. For this reason, a new theory of exhaust muffler of diesel engine based on counter-phase counteracts has been proposed. The mathematical model and the corresponding experimental validation for the new exhaust muffler based on this theory were performed.

Abstract: Problems of estimation of vibration isolation effectiveness are discussed based on vibratory power flow analysis, and a new insertion loss character — power flow insertion loss is proposed for evaluation of isolation efficiency. Spectra characteristics of the power flow insertion loss and their relationship with transmitted power flow and vibration level difference are investigated through numerical simulation. And in consideration of the inconvenience of practical testing of insertion loss and power flow, an attempt is made to set up numerical correspondence between power flow insertion loss and the current widely applied vibration level difference measurement, through theoretical analysis and experiments.

Abstract: This paper presents the design of a wide-stopband HTS bandpass filter (BPF). The 9-pole wide-stopband BPF has a center frequency 2.21GHz and bandwidth 100 MHz. Based on the step impedance resonator,this filter increase the harmonic frequency to more than 3 times of fundamental frequency. Optimization simulation results shows that insertion loss is less than 0.3 dB in the passband,and stopband suppression is greater than 80 dB within 0~f0-BW and greater than 60 db within the f0 + BW ~ 3 f0. Within the passband, dB (S (2, 1)) < -20. This design not only achieved a good wide stopband and solved the interference problem but also had a simple structure which is easy to implement.

Abstract: This paper reports the temperature dependent DC and RF characteristics of n-GaN Schottky diode simulated using Atlas/Blaze developed by Silvaco. It was found that as the temperature increases from 300K to 900K the forward current decreases due to lowering of the Schottky barrier with an increase in series-resistance and ideality factor. These observations indicates that tunneling behavior dominates the current flow rather than thermionic emission. Furthermore, the breakdown voltage decreases in reverse bias and insertion loss for RF behavior increases with respect to temperature due to the increase in capacitance near diode junction.Keywords: Atlas/Blaze, Schottky barrier, series resistance, ideality factor, insertion loss.

Abstract: At present, the control of the automobile engine exhaust noise is mainly installed exhaust muffler. Muffler design and performance research mainly around the silencing performance and the influence to engine power loss. This article built the 3d modeling of automobile exhaust muffler and through simulation analysis obtained the muffler internal acoustic pressure distribution and changes of insertion loss with frequency. Predict the silencer muffler performance as well as the influence on engine power loss. Provide a reference basis for the design of the silencer and optimization. Compared to the traditional experiment method, the method in this article has the advantages of short cycle, low cost.