摘要：电容式触摸按键具有高灵敏度和易用性,在现代电子设备、日常电器产品中广泛应用。然而,电容式触摸按键在实际应用中容易受到噪声干扰,导致误触发引起用户设置功能错乱问题。本文提出了一种基于数字信号处理(DSP)技术的噪声抑制方法,有效防止电容式触摸按键的误触发。通过对噪声源的分析和DSP算法的设计,本文将从理论到实际应用深入分析误触发的原因,并提出一系列预防设计方案,通过大量实验验证在实际应用中取得了良好的效果。

摘要：This work investigates the performance of various forward error correction codes, by which the MIMO-OFDM system is deployed. To ensure fair investigation, the performance of four modulations, namely, binary phase shift keying(BPSK), quadrature phase shift keying(QPSK), quadrature amplitude modulation(QAM)-16 and QAM-64 with four error correction codes(convolutional code(CC), Reed-Solomon code(RSC)+CC, low density parity check(LDPC)+CC, Turbo+CC) is studied under three channel models(additive white Guassian noise(AWGN), Rayleigh, Rician) and three different antenna configurations(2×2, 2×4, 4×4). The bit error rate(BER) and the peak signal to noise ratio(PSNR) are taken as the measures of performance. The binary data and the color image data are transmitted and the graphs are plotted for various modulations with different channels and error correction codes. Analysis on the performance measures confirm that the Turbo + CC code in 4×4 configurations exhibits better performance.

摘要：To meet the demands for a number of LEDs,a novel charge pump circuit with current mode control is *** is achieved by operating the current mirrors and the output current of the operational transconductance *** the steady state,the input current from power voltage retains constant,so reducing the noise induced on the input voltage source and improving the output voltage *** charge pump small-signal model is used to describe the device’s dynamic behavior and *** predictions were verified by Hspice simulation and *** driving is up to 800 mA with a power voltage of 3.6 V,and the output voltage ripple is less than 45 *** output response time is less than 8μs,and the load current jumps from 400 to 800 mA.

摘要：正交压控振荡器是高速链路中的一个关键部件.片上集成高质量品质的电感电容等无源器件是影响压控振荡器性能的关键因素.为了兼容传统的数字工艺,采用超深亚微米的数字CMOS工艺进行片上电感电容的集成,并基于此无源器件实现了基于电容耦合的正交压控振荡器,实现中心频率16.12GHz,频率调节范围为10%,1M频偏处的相位噪声为-112dBc,相位误差小于0.39°.

摘要：有经验的音响迷都深知交流电源的纯净度对于声音重放的好坏影响是多么重要，因为交流电中总是不可避免地混入了各式各样的噪声，像电动机（电冰箱、空调）、日光灯镇流器、调光器等等都是噪声的产生者，这时通常大家比较认可的简单易行办法就是添加电源滤波器。许多人会寄望于电源滤波器能消除这些电源噪声，但是目前常见的电源滤波器都是串联型设计，即通过一个滤波器来阻挡频率较高的杂波。不过滤波器并非是“一刀切”的方式进行工作，而是以一定的斜率来进行衰减，因此虽然可以把交流电里面的噪声能量降低，却无法将噪声完全消除。

摘要：Periodicity is one of the most common phenomena in the physical world. The problem of periodicity analysis （or period detection） is a research topic in several areas, such as signal processing and data mining. However, period detection is a very challenging problem, due to the sparsity and noisiness of observational datasets of periodic events. This paper focuses on the problem of period detection from sparse and noisy observational datasets. To solve the problem, a novel method based on the approximate greatest common divisor （AGCD） is proposed. The proposed method is robust to sparseness and noise, and is efficient. Moreover, unlike most existing methods, it does not need prior knowledge of the rough range of the period. To evaluate the accuracy and efficiency of the proposed method, comprehensive experiments on synthetic data are conducted. Experimental results show that our method can yield highly accurate results with small datasets, is more robust to sparseness and noise, and is less sensitive to the magnitude of period than compared methods.

摘要：The paper presents an approximated and compact derivation of the mutual displacement of Floquet eigenvectors in a class of LC tank oscillators with time varying bias. In particular it refers to parallel tank oscillators of which the energy restoring can be modeled through a train of current pulses. Since Floquet eigenvectors are acknowledged to give a correct decomposition of noise perturbations along the stable orbit in oscillator's space state, an analytical and compact model of their displacement can provide useful criteria for designers. The goal is to show, in a simplified case, the achievement of oscillators design oriented by eigenvectors. To this aim, minimization conditions of the effect of stationary and time varying noise as well as the contribution of jitter noise introduced by driving electronics are deduced from analytical expression of eigenvectors displacement.

摘要：This paper presents a new design of complementary oxide semiconductor voltage controlled oscillator (CMOS VCO) for improve tuning range and phase noise with low power consumption. Design is area efficient and easy to implement. Design is carried out in cadence and schematic editor using 180 nm technology. Simulation is done and performance results are reported. Results have been compared with earlier published work and improvements are obtained in this work.

摘要：This work describes a novel adaptive matrix/vector gradient (AMVG) algorithm for design of IIR filters and ARMA signal models. The AMVG algorithm can track to IIR filters and ARMA systems having poles also outside the unit circle. The time reversed filtering procedure was used to treat the unstable conditions. The SVD-based null space solution was used for the initialization of the AMVG algorithm. We demonstrate the feasibility of the method by designing a digital phase shifter, which adapts to complex frequency carriers in the presence of noise. We implement the half-sample delay filter and describe the envelope detector based on the Hilbert transform filter.

摘要：Coding techniques have always been a major area of scientific interest. Due to this interest, many coding schemes were invented. Eventually, their implementation in various systems contributed in the evolvement of Wireless Communications. A breakthrough was definitely Turbo coding. Particularly, the concept of joining two or more convolutional encoders in parallel (PCCC) or in serial (SCCC), along with the iterative decoding technique, literally raised the expectations of the anticipated BER performance. In fact, Concatenated Convolutional Codes clearly outperform convolutional codes. Moreover, various systems, either under development or either for future use, will have high standards. The previous systems should present exceptional tolerance of noise effects and consequently a low overall number of received errors. For this purpose a new PCCC design was developed. The system’s performance analysis, using an AWGN channel, showed better results for various iterations compared to other schemes such as typical PCCC, SCCC and finally a Convolutional encoder with a Viterbi decoder.