Research on the Passivation Function of Si＿3N＿4 Film to YBCO Superconducting Film

ＲｅｓｅａｒｃｈｏｎｔｈｅＰａｓｓｉｖａｔｉｏｎＦｕｎｃｔｉｏｎｏｆＳｉ＿３Ｎ＿４ＦｉｌｍｔｏＹＢＣＯＳｕｐｅｒｃｏｎｄｕｃｔｉｎｇＦｉｌｍＺｈａｎｇＹｕｔｉａｎ；ＪｉｎＢｏＡＮＤＱｉａｎＰｉｎｇｋａｉ（ＤｅｐａｒｔｍｅｎｔｏｆＡｐｐｌｉｅｄＳｃｉｅ...     

有线电视宽带网络常用名词缩语

ＡＣＳ(ＡｒｅａＣｏｍｍｕｎｉｃａｔｉｏｎＳｙｓｔｅｍ)区域通信系统 　ＡＰＳＳ(ＡｕｔｏｍａｔｉｃＰｒｏｇｒａｍＳｅａｒｃｈＳｙｓｔｅｍ)自动节目搜索系统 　ＡＳＩ(ＡｓｙｎｃｈｒｏｎｏｕｓＳｅｒｉａｌＩｎｔｅｒｆａｃｅ)异步串行接口 ,用于传送码流的一个标准ＤＶＢ接口 　ＡＴＶ(ＡｄｖａｎｃｅｄＴｅｌｅＶｉｓｉｏｎ)先进电视 ,美国数字电视标准 　ＢＣＴ(ＢａｎｄｗｉｄｔｈＣｏｍｐｒｅｓｓｉｏｎＴｅｃｈｎｉｑｕｅ)带宽压缩技术 　ＢＥＲ(ＢａｓｉｃＥｎｃｏｄｉｎｇＲｕｌｅｓ)基本编码规则 　ＢＦＡ(ＢａｒｅＦｉｂ…     

电信英语及其缩略语解释（十）

ＢＥＰ Ｂｌｏｃｋ Ｅｒｒｏｒ Ｐｒｏｂａｂｉｌｉｔｙ 码组差错概率ＢＥＲ Ｂｉｔ Ｅｒｒｏｒ Ｒａｔｉｏ 误码率 ＢＥＲ指传输中码元的错误概率。ＢＥＲＴ Ｂｉｔ Ｅｒｒｏｒ Ｒａｔｉｏ Ｔｅｓｔｅｒ 误码率监测器ＢＥＴＲＳ Ｂａｓｉｃ Ｅｘｃｈａｎｇｅ Ｔｅｌｅｃｏｍｍｕｎｉｃａｔｉｏｎｓ Ｒａｄｉｏ Ｓｅｒｖｉｃｅ 基本交换无线通信业务ＢＥＸ Ｂｒｏａｄｂａｎｄ ＥＸｃｈａｎｇｅ 宽带交换机ＢＥＸＲ Ｂａｓｉｃ ＥＸｃｈａｎｇｅ Ｒａｄｉｏ 基本交换无线系统ＢＦＩ Ｂａｄ Ｆｒａｍｅ Ｉｎｄｉｃａｔｉｏｎ 坏帧指示 ＢＦ…     

Group Theory Approach for the Stimulated Raman Scattering in Fiber

ＧｒｏｕｐＴｈｅｏｒｙＡｐｐｒｏａｃｈｆｏｒｔｈｅＳｔｉｍｕｌａｔｅｄＲａｍａｎＳｃａｔｔｅｒｉｎｇｉｎＦｉｂｅｒＹａｎｇＢｏｊｕｎＡＮＤＧｕｏＷａｎｗｅｎ（ＤｅｐａｒｔｍｅｎｔｏｆＢａｓｉｃＳｃｉｅｎｃｅｓ，ＢｅｉｊｉｎｇＵｎｉｖｅｒｓｉｔｙｏｆＰ...     

Intelligent Flow Control Technique of ABR Service in ATM Networks Based on Fuzzy Neural Networks

ＩｎｔｅｌｉｇｅｎｔＦｌｏｗＣｏｎｔｒｏｌＴｅｃｈｎｉｑｕｅｏｆＡＢＲＳｅｒｖｉｃｅｉｎＡＴＭＮｅｔｗｏｒｋｓＢａｓｅｄｏｎＦｕｚｚｙＮｅｕｒａｌＮｅｔｗｏｒｋｓ①ＺｈａｎｇＬｉａｎｇｊｉｅＬｉＹａｎｄａＬｉＱｉｎｇｈｕａＷａｎｇＰｕ（ＤｅｐｔｏｆＡ...     

Laser Annealing Modification of Diamond-like Atomic-scale Composite Films Studied by Micro Raman Spectroscopy

ＬａｓｅｒＡｎｎｅａｌｉｎｇＭｏｄｉｆｉｃａｔｉｏｎｏｆＤｉａｍｏｎｄｌｉｋｅＡｔｏｍｉｃｓｃａｌｅＣｏｍｐｏｓｉｔｅＦｉｌｍｓＳｔｕｄｉｅｄｂｙＭｉｃｒｏＲａｍａｎＳｐｅｃｔｒｏｓｃｏｐｙＪ．Ｚ．ＷａｎｇａＦｒｅｄＨ．ＰｏｌａｋａＢ．Ｆ．Ｄｏｒ...     

A Frequency－Diversity Spread－Spectrum Multiple Access System with Random Signature Sequences

ＡＦｒｅｑｕｅｎｃｙ－ＤｉｖｅｒｓｉｔｙＳｐｒｅａｄ－ＳｐｅｃｔｒｕｍＭｕｌｔｉｐｌｅＡｃｃｅｓｓＳｙｓｔｅｍｗｉｔｈＲａｎｄｏｍＳｉｇｎａｔｕｒｅＳｅｑｕｅｎｃｅｓＣａｏＹｅｗｅｎ；ＸｉａｎｇＨａｉｇｅ（ＰｅｋｉｎｇＵｎｉｖｅｒｓｉｔｙ，Ｂｅｉｊｉ...     

Theoretical Bounds and Practical Constructions for Families of One－Coincidence Sequences in FHMA

ＴｈｅｏｒｅｔｉｃａｌＢｏｕｎｄｓａｎｄＰｒａｃｔｉｃａｌＣｏｎｓｔｒｕｃｔｉｏｎｓｆｏｒＦａｍｉｌｉｅｓｏｆＯｎｅ－ＣｏｉｎｃｉｄｅｎｃｅＳｅｑｕｅｎｃｅｓｉｎＦＨＭＡＭｅｉＷｅｎｈｕａ；ＹａｎｇＹｉｘｉａｎ（ＢｅｉｊｉｎｇＡｅｒｏｎａｕｔｉｃａｌ...     

Photoelastic Fabry－Perot Optical Modulator Based on a Silicon－on－Insulator Structure

ＰｈｏｔｏｅｌａｓｔｉｃＦａｂｒｙ－ＰｅｒｏｔＯｐｔｉｃａｌＭｏｄｕｌａｔｏｒＢａｓｅｄｏｎａＳｉｌｉｃｏｎ－ｏｎ－ＩｎｓｕｌａｔｏｒＳｔｒｕｃｔｕｒｅ￥ＹＵＬｉｓｈｅｎ（ＢｅｉｊｉｎｇＵｎｉｖｅｒｓｉｔｙ，Ｂｅｉｊｉｎｇ１００８７１，ＣＨＮ）ＧＵＡ...     

广播电视、电信机构(组织)常见名称中英文对照

◇ＡｕｓｔｒｉａｌｉａｎＢｒｏａｄｃａｓｔｉｎｇＣｏｍｍｉｓｓｉｏｎ澳大利亚广播委员会◇ＡＢＵ(ＡｓｉａｎＢｒｏａｄｃａｓｔｉｎｇＵｎｉｏｎ)亚洲广播联盟 (亚广联 )◇ＡＥＳ(ＡｕｄｉｏＥｎｇｉｎｅｅｒｉｎｇＳｏｃｉｅｔｙ)声频工程协会◇ＡＦＩＰ (ＡｍｅｒｉｃａｎＦｅｄｅｒａｔｉｏｎｆｏｒｉｎｆｏｒｍａｔｉｏｎｐｒｏｃｅｓｓｉｎｇ)美国信息处理联合会◇ＡＩＥＥ(ＡｍｅｒｉｃａｎＩｎｓｔｉｔｕｔｅｏｆＥｌｅｃｔｒｉｃａｌＥｎｇｉｎｅｅｒｓ)美国电气工程师协会◇ＡＩＲ(ＡｍｅｒｉｃａｎＩｎｓｔｉｔｕｔｅｏｆＲ…     

Near-Minimum Bit-Error Rate Equalizer Adaptation for PRML Systems

Receivers for partial response maximum-likelihood systems typically use a linear equalizer followed by a Viterbi detector. The equalizer tries to confine the channel intersymbol interference to a short span in order to limit the implementation complexity of the Viterbi detector. Equalization is usually made adaptive in order to compensate for channel variations. Conventional adaptation techniques, e.g., LMS, are, in general, suboptimal in terms of bit-error rate (BER). In this paper, we present a new equalizer adaptation algorithm that seeks to minimize the BER at the Viterbi detector output. The algorithm extracts information from the sequenced amplitude margin (SAM) histogram and incorporates a selection mechanism that focuses adaptation on particular data and noise realizations. The selection mechanism is based on the reliability of the add compare select (ACS) operations in the Viterbi detector. From a complexity standpoint, the algorithm is essentially as simple as the conventional LMS algorithm. Moreover, we present a further simplified version of the algorithm that does not require any hardware multiplications. Simulation results, for an idealized optical storage channel, confirm a substantial performance improvement relative to existing adaptation algorithms.     

On Optimal Detection of Band-Limited PAM Signals with Excess Bandwidth

PAM data transmission receivers accomplishing maximum likelihood sequence detection (MLSD) usually require a matched filter prefilter, a sampler at the symbol rate, and a Viterbi algorithm detector. When the channel is unknown or slowly changing, one must use an adaptive matched filter prefilter. We examine an alternative optimum receiver whose optimality is independent of the matched filter prefilter and which is applicable when the channel is effectively band-limited. The sampler in the proposed receiver operates at a rate faster than the data symbol rate, enabling one to replace the matched filter by a fixed low-pass filter and still ensure that the maximum likelihood detector is supplied with a set of sufficient statistics. It is shown that the matched filter is incorporated within a modified Viterbi detector without increasing the number of states in the algorithm, although the Viterbi detector must perform computations at approximately twice the usual rate. Simulations support the optimality of the new receiver and quantitatively indicate the degradation in performance experienced by some adaptive receivers previously proposed.     

Carrier Reference Error Sensitivity of a Viterbi Detector for PAM Data Transmission

In this paper we extend the probability of error analysis for Viterbi detectors for PAM data transmission to include the effects of steady-state carrier reference errors. It has earlier been found that the Viterbi detector is sensitive to the effects of constant carrier phase errors. However, for two reasonably complicated voiceband pulses taken from the literature, we find that the Viterbi detector is no more sensitive to random carrier phase errors than is a standard quantizing detector.     

遗传算法在多用户检测中的应用研究

本文针对CDMA系统中多用户检测的组合优化问题,提出一种结合遗传算法和Hopfield神经网络的检测方法。该方法首先由遗传算法给神经网络提供一个初始解,神经网络在此基础上再进行局部寻优。研究表明：这种方法具有平方的计算复杂度,优于Hopfield神经网络检测方法、以及单独采用遗传算法的检测方法,对远近问题不敏感,具有良好的误码率性能和抗多址干扰性能。     

Improved performance of coded digital FM

The performance of convolutionally encoded narrow-band digital FM with Viterbi decoding was considered in some detail by Simon (1983) for a noncoherent limiter/discriminator (L/D) with integrate and dump (I&D) bit detection. Employing a new threshold receiver which averages the output of the I&D detector with the output of a sample and hold (S&H) detector, a 3-dB improvement over Simon's results for the bit error probability with FM clicks is shown to be achievable. At low error rates, the performance of this new receiver is, moreover, comparable to that obtained when the clicks are exactly removed by Simon's hypothetical “genie”     

A 110 MHz 350 mW 0.6 μm CMOS 16-state generalized-target Viterbidetector for disk drive read channels

An architecture for efficiently implementing linear and nonlinear Viterbi detectors for magnetic read channels is presented. By employing generalized noiseless target values for the Viterbi trellis, the detector is better able to adapt to the actual binary data storage channel and less equalization is needed, resulting in a significant reduction in the probability of error. An implementation example is presented for the case of a 16-state Viterbi detector having a capability of handling any noiseless target of up to five adjacent nonzero values. In a 0.6 μm (drawn) 3.0 V CMOS process, the design has been implemented with a die area of 9 mm² consuming under 350 mW of power when operated at 110 MHz     

Soft-decision phase detection with Viterbi decoding for CPM signals

It is known that continuous phase modulation (CPM) signals can be optimally detected by using coherent demodulation followed by Viterbi decoding. However, such a receiver is generally complicated, particularly at higher numbers of states, as it requires many correlators and many reference signals in the demodulator. In this study, a much simpler receiver, which employs a soft-decision phase detector followed by a Viterbi decoder, is proposed for the detection of CPM signals. The phase detector makes a decision in favor of one of the preselected phase subregions at the end of every interval, which is then used to calculate metrics for decoding. As in optimal detection, the Viterbi decoder decodes according to the trellis structure of CPM signals. The proposed receiver is analyzed in a narrow-band Gaussian channel with 2REC, 2-h, and trellis-coded continuous-phase frequency-shift keying signals. Numerical results show that the proposed receiver performs close to optimal detection with all types of signals considered in this study. The effect of the number of subregions in the phase detector is examined     

A Class of Reduced-Complexity Viterbi Detectors for Partial Response Continuous Phase Modulation

Partial response continuous phase modulation (CPM) gives constant envelope digital modulation schemes with excellent power spectra. Both narrow main lobe and low spectral tails can be achieved. When these signals are detected in an optimum coherent maximum likelihood sequence detector (Viterbi detector), power efficient schemes can also be designed, sometimes at the expense of receiver complexity. This paper describes a general class of simple Viterbi detectors with reduced complexity compared to the optimum case. The key idea is that the approximate receiver is based on a less complex CPM scheme than the transmitted scheme. The asymptotically optimum reduced-complexity receiver is found for a variety of transmitted schemes and various complexity reduction factors, for a specific class of receivers and modulation indexes. A new distance measure is introduced for the performance analysis. Smooth schemes based on raised cosine pulses are analyzed and simulated for the case of simplified reception. A graceful performance degradation occurs with the reduction of complexity.     

Performance of noncoherent maximum-likelihood sequence detection for differential OFDM systems with diversity reception

For the single-carrier M-ary differential phase-shift keying (MDPSK), the multiple-symbol differential detector, or the noncoherent maximum-likelihood sequence detector (NSD), and its three special cases, namely, the noncoherent one-shot detector, the linearly predictive decision-feedback (DF) detector, and the linearly predictive Viterbi receiver are reviewed based on a hierarchical interpretation. For the multicarrier transmission, the differential orthogonal frequency division multiplexing (OFDM) systems with diversity reception are discussed. It is well known that there are two types of differential OFDM systems, namely, the time domain differential OFDM (TD-OFDM) and the frequency domain differential OFDM (FD-OFDM). In this paper, the NSD and its special cases are incorporated to the differential OFDM systems. Furthermore, we provide a simple closed-form bit-error-rate (BER) expression for the differential OFDM systems utilizing the noncoherent one-shot detector with diversity reception in the time-varying multipath Rayleigh fading channels. Numerical results have revealed that, with multi-antenna diversity reception, the performance of the noncoherent one-shot detector is improved significantly. However, when only one or two receive antennas are available, the implementation of the linearly predictive DF detector or the linearly predictive Viterbi receiver is necessary for achieving better and satisfactory performance.     

Performance of Volterra and MLSD receivers for nonlinearband-limited satellite systems

This paper evaluates the performance of Volterra equalizers and maximum-likelihood sequence detection (MLSD) receivers for compensation of signal distortion in nonlinear band-limited satellite systems. In addition, the performance of a receiver with a fractionally-spaced equalizer followed by a Volterra equalizer is studied (FSE-Volterra equalizer). For the equalizers, adaptation of the equalizer weights is considered including a multiple-step LMS algorithm which improves the convergence characteristics. Two MLSD receiver structures are considered: the optimum receiver consisting of a matched-filter bank followed by a Viterbi (1967) detector and a suboptimum receiver consisting of a single receiver filter followed by a Viterbi detector. The performance of the MLSD receivers is then compared to that of the equalizers