Muhammad Arsalan¹, Falin Wu^1,*

CMES-Computer Modeling in Engineering & Sciences, Vol.119, No.2, pp. 249-261, 2019, DOI:10.32604/cmes.2019.04430

Abstract A good design of LNA for S band satellite navigation receivers and 4G LTE wireless communication system has been implemented in this paper. Due to increased congestion in the present L band, the S Band frequency from 2483.5-2500 MHz has been allocated for the future satellite navigation systems. For this purpose ATF-34143 amplifier (pHEMT) having high electron mobility and fast switching response has been chosen due to its very low Noise Figure (NF). The amplifier has been designed having bandwidth of 0.8 GHz from 1.8-2.6 GHz. Because of the large bandwidth, the amplifier could serve many wireless communication applications including… More >

Y,ong Gao¹, Shubi Zhang^1,*, Kefei Zhang^2,*, Shijin Li¹

CMES-Computer Modeling in Engineering & Sciences, Vol.119, No.2, pp. 349-363, 2019, DOI:10.32604/cmes.2019.03943

Abstract Interferometric phase filtering is one of the key steps in interferometric synthetic aperture radar (InSAR/SAR). However, the ideal filtering results are difficult to obtain due to dense fringe and low coherence regions. Moreover, the InSAR/SAR data range is relatively large, so the efficiency of interferential phase filtering is one of the major problems. In this letter, we proposed an interferometric phase filtering method based on an amended matrix pencil and linear window mean filter. The combination of the matrix pencil and the linear mean filter are introduced to the interferometric phase filtering for the first time. First, the interferometric signal… More >

Zhexi Zhang¹, Zhiguo Qu^1,2,*

Journal of Quantum Computing, Vol.1, No.2, pp. 89-109, 2019, DOI:10.32604/jqc.2019.07415

Abstract How to establish a secure and efficient quantum network coding algorithm is one of important research topics of quantum secure communications. Based on the butterfly network model and the characteristics of easy preparation of Bell states, a novel anti-noise quantum network coding protocol is proposed in this paper. The new protocol encodes and transmits classical information by virtue of Bell states. It can guarantee the transparency of the intermediate nodes during information, so that the eavesdropper Eve disables to get any information even if he intercepts the transmitted quantum states. In view of the inevitability of quantum noise in quantum… More >

Xiaorong Zhao¹, Hongjin Zhu¹, Peizhong Shi¹, Chunpeng Ge², Xiufang Qian^1,*, Honghui Fan¹, Zhongjun Fu¹

CMC-Computers, Materials & Continua, Vol.60, No.1, pp. 133-145, 2019, DOI:10.32604/cmc.2019.05661

Abstract With the rapid development of ultra-wideband communications, the design requirements of CMOS radio frequency integrated circuits have become increasingly high. Ultra-wideband (UWB) low noise amplifiers are a key component of the receiver front end. The paper designs a high power gain (S₂₁) and low noise figure (NF) common gate (CG) CMOS UWB low noise amplifier (LNA) with an operating frequency range between 3.1 GHz and 10.6 GHz. The circuit is designed by TSMC 0.13 μm RF CMOS technology. In order to achieve high gain and flat gain as well as low noise figure, the circuit uses many technologies. To improve… More >

Zhiguo Qu^1,*, Shengyao Wu², Wenjie Liu¹, Xiaojun Wang³

CMC-Computers, Materials & Continua, Vol.59, No.2, pp. 607-624, 2019, DOI:10.32604/cmc.2019.02656

Abstract In the field of quantum communication, quantum steganography is an important branch of quantum information hiding. In a realistic quantum communication system, quantum noises are unavoidable and will seriously impact the safety and reliability of the quantum steganographic system. Therefore, it is very important to analyze the influence of noise on the quantum steganography protocol and how to reduce the effect of noise. This paper takes the quantum steganography protocol proposed in 2010 as an example to analyze the effects of noises on information qubits and secret message qubits in the four primary quantum noise environments. The results show that… More >

Peng Fu^1,2, Qianqian Xu¹, Jieyu Zhang³, Leilei Geng^4,*

CMC-Computers, Materials & Continua, Vol.59, No.2, pp. 509-515, 2019, DOI:10.32604/cmc.2019.05250

Abstract The superpixel segmentation has been widely applied in many computer vision and image process applications. In recent years, amount of superpixel segmentation algorithms have been proposed. However, most of the current algorithms are designed for natural images with little noise corrupted. In order to apply the superpixel algorithms to hyperspectral images which are always seriously polluted by noise, we propose a noise-resistant superpixel segmentation (NRSS) algorithm in this paper. In the proposed NRSS, the spectral signatures are first transformed into frequency domain to enhance the noise robustness; then the two widely spectral similarity measures-spectral angle mapper (SAM) and spectral information… More >

Zhiguo Qu^1,*, Tiancheng Zhu², Jinwei Wang¹, Xiaojun Wang³

CMC-Computers, Materials & Continua, Vol.56, No.1, pp. 47-59, 2018, DOI: 10.3970/cmc.2018.02215

Abstract In this paper, a novel quantum steganography protocol based on Brown entangled states is proposed. The new protocol adopts the CNOT operation to achieve the transmission of secret information by the best use of the characteristics of entangled states. Comparing with the previous quantum steganography algorithms, the new protocol focuses on its anti-noise capability for the phase-flip noise, which proved its good security resisting on quantum noise. Furthermore, the covert communication of secret information in the quantum secure direct communication channel would not affect the normal information transmission process due to the new protocol’s good imperceptibility. If the number of… More >

Mingxu Yi¹, Lifeng Wang^1,2, Yalin Pan¹, Jun Huang¹

CMES-Computer Modeling in Engineering & Sciences, Vol.109-110, No.5, pp. 427-446, 2015, DOI:10.3970/cmes.2015.109.427

Abstract Active cancellation stealth is a significant developing direction in modern stealth technology field. In this paper, according to characteristics of linear frequency modulated (LFM) signal and nonlinear frequency modulated (NLFM) signal, the cancellation signal was designed. An important parameter called cancellaty which is used to measure the effect of cancellation is proposed. The basic theory of active cancellation stealth is introduced. Based on radar target fluctuation models, the formulas of the radar detection probability are given. Combining the definition of cancellaty with radar detection probability, the effective scope of the cancellaty is ensured. Simulation results show the effectiveness and the… More >

Jun Huang^1,2, Chaopu Zhang¹, Song Xiang², Liu Yang¹, Mingxu Yi¹

CMES-Computer Modeling in Engineering & Sciences, Vol.108, No.5, pp. 315-330, 2015, DOI:10.3970/cmes.2015.108.315

Abstract In order to accurately predict the aerodynamic noise of the propeller, a hybrid method combining Computational Fluid Dynamics (CFD) method with Boundary Element Method (BEM) is developed in this paper. The calculation includes two steps: firstly, the unsteady viscous flow around the propeller is calculated using the CFD method to acquire the noise source information; secondly, the radiated sound pressure is calculated using BEM method in the frequency domain. In comparison with the experimental results from wind tunnel, the calculated results of aerodynamic performance are rather desirable. The simulation and experimental results of aerodynamic noise are well fitted. The directivity… More >

Xu Yong^1,2, Feng Jing¹, Xu Wei¹, Gu Rencai¹

CMES-Computer Modeling in Engineering & Sciences, Vol.106, No.5, pp. 309-322, 2015, DOI:10.3970/cmes.2015.106.309

Abstract In this paper, bifurcation analysis and numerical simulations are performed on the FitzHugh-Nagumo system in the presence of Lévy stable noise. The stationary probability density functions are obtained to examine the influences of noise intensity and stability index. Results show that under the influences of noise intensity and stability index, the dynamic of the FitzHugh-Nagumo model can be well characterized through the concept of stochastic bifurcation, consisting in qualitative changes of the stationary probability distribution. Then, the mean passage time between the resting and action state is investigated as functions of noise intensity and stability index of the external signal… More >