An improved method of MOSFET modeling and parameter extraction

A method is presented to accurately determine MOSFET modeling parameters from a single linear region (VDS< 2kBT/q)ID- VGSmeasurement based on the operation of a single transistor in the strongly inverted regime. The intrinsic values of the surface scattering parameter θsand the transistor gain β0may be separated from the series resistance Rsand drain bias VDSeffects while including band bending beyond the 2φFpoint. The mobility (excluding surface scattering effects), threshold voltage, bulk doping, and flat-band voltage are also determined.     

一种改进的LPCC参数提取方法研究

为了提高语音信号的识别率。提出了一种改进的LPCC参数提取方法。该方法先对语音信号进行预加重、分帧加窗处理。然后进行小波分解,在此基础上提取LPCC参数,从而构成新向量作为每帧信号的特征参数。最后采用高斯混合模型（GMM）进行说话人语音识别,实验表明新特征参数取得了较好的识别率。     

采用新结构与新工艺降低SiGe HBT基区串联电阻

采用新型调制掺杂量子阱基区结构和掩埋金属自对准工艺方法,在器件的纵向结构和制备手段上同时进行改进,使超薄基区小尺寸SiGeHBT的基区横向电阻和接触电阻分别降低42%和55%以上,有效解决了基区串联电阻的问题。     

An efficient crosstalk parameter extraction method for high-speedinterconnection lines

A proposal is presented for an effective extraction method for crosstalk model parameters of high-speed interconnection lines. In the extraction procedure, mutual capacitance and mutual inductance of the coupled interconnection lines are extracted based on S-parameter measurement, time-domain-reflectometry (TDR) measurement and subsequent microwave network analysis. The extraction method is useful for characterizing homogeneous guiding structures, where the propagation of coupled transverse electromagnetic (TEM) modes is supported. In contrast to previous extraction methods, the suggested procedure requires fewer on-wafer probing steps and does not need matched terminations in the test device for high-frequency probing. The extracted models can be readily used with simulation program with integrated circuit emphasis (SPICE) circuit simulation. The procedure can also be used for modeling the crosstalk in packaging structures and multichip modules (MCMs). The proposed procedure has been successfully applied to the crosstalk model extraction of on-chip interconnection lines. Crosstalk model parameters were obtained for different line structures, spaces, and widths. Finally, the validity and reliability of the extracted models were examined by comparing a SPICE circuit simulation using the extracted crosstalk model parameters with high-speed time-domain crosstalk measurement. A close agreement was observed in the amplitude and pulse shape between the simulation and the measurement, showing the accuracy and usefulness of the proposed extraction method     

An improved and simple parameter extraction method and scaling model for RF MOSFETs up to 40 GHz

In this article, a simple and efficient extraction procedure for the extrinsic gate, drain and source resistances is presented. The substrate network parameter, C _sub, dependent on the drain–source (V _ds) voltage is extracted in transistor cut-off region. The scaling rules of the extrinsic and intrinsic parameters are given in detail. Good agreement is obtained between the simulated and measured results for the 0.13?µm radio frequency metal oxide semiconductor field effect transistors in the frequency range of 0.1–40?GHz.     

一种改进的跳频信号参数估计方法

针对在跳频信号跳变时刻和跳变频率估计方面实时性和估计精度无法同时兼顾的问题,提出了一种基于短时傅立叶变换(STFT)和多重信号分类(MUSIC)算法的跳频信号参数估计方法。在建立跳频信号数学模型的基础上,利用STFT选取较大时间窗对整个信号在时域进行粗搜索,生成时频谱图,提取时频脊线从而获得跳变时刻,然后选取较小时间窗在已知跳变时间段利用STFT进行跳变时刻的细估计,并利用MUSIC算法进行频率的精确估计。该方法利用STFT的二次估计,减少了MUSIC搜索范围,从而降低了时间开销。仿真表明该算法的跳变时刻频率估计精度高,实时性能满足参数测量需求。     

一种改进的鱼眼图像有效区域提取方法

鱼眼镜头拍摄的图像具有严重的变形,要想利用鱼眼图像的信息,就必须将其校正为常规的线性图像。提取鱼眼图像有效区域是进行校正的前提,同时,鱼眼图像有效区域提取的精度将影响到鱼眼图像校正的效果。传统最常用的方法是扫描线逼近法,计算量较小,速度较快,但也具有抗干扰性差的缺陷。针对有效区域边界存在黑色像素点影响传统算法精度的缺点,提出通过改变扫描步长,垂线缩进的改进算法。实验结果表明,改进算法能准确确定有效区域的中心坐标和半径,具有精度高、耗时少、满足实时性要求的特点,具有较强的实用价值。     

An improved shape shifting method of critical area extraction

As die size and complexity increase, accurate and efficient extraction of the critical area is essential for yield prediction. Aiming at eliminating the potential integration errors of the traditional shape shifting method, an improved shape shifting method is proposed for Manhattan layouts. By mathematical analyses of the relevance of critical areas to defect sizes, the critical area for all defect sizes is modeled as a piecewise quadratic polynomial function of defect size, which can be obtained by extracting critical area for some certain defect sizes. Because the improved method calculates critical areas for all defect sizes instead of several discrete values with traditional shape shifting method, it eliminates the integration error of the average critical area. Experiments on industrial layouts show that the improved shape shifting method can improve the accuracy of the average critical area calculation by 24.3% or reduce about 59.7% computational expense compared with the traditional method.     

Direct parameter extraction of SiGe HBTs for the VBIC bipolar compact model

An improved direct parameter extraction method of SiGe heterojunction bipolar transistors (HBTs) for the vertical bipolar intercompany (VBIC)-type hybrid-/spl pi/ model is developed. All the equivalent circuit elements are extracted analytically from S-parameter data only and without any numerical optimization. The proposed technique of the parameter extraction, differing from the previous ones, focuses on correcting the pad de-embedding error for an accurate and invariant extraction of intrinsic base resistance (R/sub bi/), formulating a new parasitic substrate network, and improving the extraction procedure of transconductance (g/sub m/), dynamic base-emitter resistance (r/sub /spl pi//), and base-emitter capacitance (C/sub /spl pi//) using the accurately extracted R/sub bi/. The extracted parameters are frequency-independent and reliable due to elimination of any de-embedding errors. The agreements between the measured and model-calculated data are excellent in the frequency range of 0.2-10.2 GHz over a wide range of bias points. Therefore, we believe that the proposed extraction method is a simple and reliable routine applicable to the optimization of transistor design, process control, and the improvement of VBIC compact model, especially for SiGe HBTs.     

智能划分移动通信网络话务场景的改进方法

【】本文介绍了一种智能划分移动通信话务场景的改进方法。通过运用指标均方差加权、二分聚类确定场景类别和概率方差确定场景特性的技术实现提升智能划分小区话务场景的精确度。     

An improved vector quantization method using deep neural network

To address the challenging problem of vector quantization (VQ) for high dimensional vector using large coding bits, this work proposes a novel deep neural network (DNN) based VQ method. This method uses a k-means based vector quantizer as an encoder and a DNN as a decoder. The decoder is initialized by the decoder network of deep auto-encoder, fed with the codes provided by the k-means based vector quantizer, and trained to minimize the coding error of VQ system. Experiments on speech spectrogram coding demonstrate that, compared with the k-means based method and a recently introduced DNN-based method, the proposed method significantly reduces the coding error. Furthermore, in the experiments of coding multi-frame speech spectrogram, the proposed method achieves about 11% relative gain over the k-means based method in terms of segmental signal to noise ratio (SegSNR).     

An effective parameter extraction method based on memetic differential evolution algorithm

This paper provides an effective method for parameter extraction of microelectronic devices and elements. A novel method, memetic differential evolution (MDE) algorithm, is proposed in this paper. By combining differential evolution (DE) algorithm, mutations in immune algorithm (IA), and special operators for parameter extraction, MDE possesses characteristics of high accuracy, stability, generality, and efficiency. The effectiveness of the method has been shown by two typical examples, including small-signal equivalent circuit models for an AlGaN/GaN HEMT device up to 40 GHz, as well as an equivalent circuit model for on-chip differential spiral inductors. In both cases, the initial values and parameter ranges of the elements in the equivalent circuits are hard to determine in optimization. The results and comparisons with Levenberg-Marquardt (LM) algorithm, genetic algorithm (GA), particle swarm optimization (PSO) algorithm and canonical DE algorithm, demonstrate the superiority of MDE in terms of accuracy and generality.     

一种改进的InP HBT小信号模型的直接提取法

提出了一种改进的直接提取方法来提取InP HBT小信号等效电路中的模型参数,并将其成功地应用InP异质结双极晶体管（HBT）小信号等效电路。在所采用的模型中考虑了分布式基极-集电极电容效应。与其他直接参数提取方法相比,该方法从外围寄生元件到内部本征元件依次进行参数提取,提取过程较为清晰。除寄生参数外,其余所有的参数计算均未经过任何简化近似。该方法依赖于S参数的测量,所有等效电路参数直接从S参数数据中提取,而无需任何基于初始值的近似。在0.1 ~ 40 GHz的频率范围内,直接提取法在InP HBT上得到了成功的验证,并在整个频率范围内得到了较好的测量结果与计算结果的一致性。     

一种改进的考虑划痕的关键面积计算模型和方法

关键面积计算对于集成电路成品率的准确预测有着重要的意义。为了得到精确的结果,关键面积计算需要根据缺陷形状的不同选择适当的缺陷模型。针对化学机械研磨引入的划痕,提出了一种线性缺陷模型来计算其关键面积。在此基础上进一步考虑了线端效应的影响,对考虑划痕的关键面积计算模型提出了改进。实验结果表明改进后模型的计算结果更为准确。     

基于波段选择改进的高光谱端元提取方法

为了解决传统N-FINDR算法降维时破坏像元光谱曲线的物理意义这个问题, 采用波段选择方法中的最佳指数法代替特征提取, 改进N-FINDR算法的降维方式; 利用模拟和真实高光谱数据进行实验, 分别用改进的N-FINDR算法与其它两种算法提取端元, 并用全约束最小二乘法解混。结果表明, 改进的N-FINDR算法的解混精度更高, 用时更少。用波段选择代替特征提取改进降维方式, 保留了光谱曲线的物理意义, 在N-FINDR算法中是可行的。     

An improved Boolean algebra method for computing the network reliability

This paper presents a new method, the HHL 91 algorithm, for calculating the network system reliability by sum of disjoint products (sdp). The main feature of the HHL 91 is its ability to properly arrange the order of minimal paths as well as to apply inversion to products of several variables. While the Abraham algorithm and its successors yield relatively short sdp forms of the structure functions of coherent network systems, this new method generates shorter disjoint products than any other known sdp method. Because the system reliability formula is considerably reduced in size, there will be a sharp decrease both in computation time and in rounding errors.     

Efficient BEM-based substrate network extraction in silicon SoCs

This paper is focused on the efficient extraction of the substrate network in complex system-on-chip designs. A boundary element method (BEM)-based approach, which employs spatial-frequency domain Green's function analysis, is considered and very high efficiency is achieved by a novel formulation of the boundary conditions which describe both resistive and capacitive couplings. The efficiency of the proposed technique is further increased taking advantage of the inherent information compression provided by the discrete cosine transform (DCT). The effectiveness of the proposed method is assessed by comparison with a commercial substrate extraction tool and its computational advantage is illustrated on the basis of computer simulation results.     

An improved method of selecting network topology for optimal terminal reliability

Given the permissible network topology and cost, it is generally required to determine the topology so that source-to-terminal reliability is maximum. Such an exercise may be needed for any type of network; like that of computers, communication lines, transmission lines, pipelines etc. In this paper two heuristic methods of determining such an optimal network are discussed and compared with that of Chopra et al. Microelectron. Reliab.24, 911–913, 1985. It is shown that the method of Chopra et al. fails quite often and the ones proposed are found to be successful in majority of cases.