Electronics and Communications in Japan (Part III: Fundamental Electronic Science)最新文献_第10页

Performance analysis of UWB impulse radar receiver using parallel IPCP 基于并行IPCP的超宽带脉冲雷达接收机性能分析

Electronics and Communications in Japan (Part III: Fundamental Electronic Science) Pub Date : 2007-03-28 DOI: 10.1002/ecjc.20303

Hiroyuki Hatano, Takaya Yamazato, Hiraku Okada, Masaaki Katayama

{"title":"Performance analysis of UWB impulse radar receiver using parallel IPCP","authors":"Hiroyuki Hatano, Takaya Yamazato, Hiraku Okada, Masaaki Katayama","doi":"10.1002/ecjc.20303","DOIUrl":"https://doi.org/10.1002/ecjc.20303","url":null,"abstract":"<p>This paper considers a vehicle-borne target detection system for short range in which an UWB (Ultra Wideband) impulse radar is used. The UWB impulse radar uses a pulse with widths of less than nanosecond order. Therefore, many multipath returns are observed on the receiving side. An IPCP (Inter-Period Correction Processing) receiver that resolves complexity of the receiver caused by multiple paths has been proposed. However, the integration time of the correlator in the IPCP receiver is limited by the period of the transmission signal (code length) and affects the range measurement accuracy. This paper considers vehicle mounting for applications. In order to assure safety, a receiver is constructed with several IPCP receivers in parallel, so that the range measurement accuracy is improved. In addition, a receiver which reduces the complexity of threshold setting in the conventional IPCP receiver when several targets are detected is proposed. The outputs of these receivers are derived analytically and improvement of the range measurement accuracy is confirmed. Further, based on the analytical results, the output of each receiver is characterized and the relationship of the threshold, detection probability, and false error probability is derived. Finally, the characteristics of use of the receiver as a vehicle-mounted radar are evaluated by simulation. © 2007 Wiley Periodicals, Inc. Electron Comm Jpn Pt 3, 90(7): 1–14, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecjc.20303</p>","PeriodicalId":100407,"journal":{"name":"Electronics and Communications in Japan (Part III: Fundamental Electronic Science)","volume":"90 7","pages":"1-14"},"PeriodicalIF":0.0,"publicationDate":"2007-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1002/ecjc.20303","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"71992454","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 4

Reducing peak power for coded OFDM systems by multiple symbol mapping 利用多符号映射降低编码OFDM系统的峰值功率

Electronics and Communications in Japan (Part III: Fundamental Electronic Science) Pub Date : 2007-03-01 DOI: 10.1002/ECJC.10168

M. Harada, Takaya Yamamoto, Hiraku Okada, M. Katayama, A. Ogawa

{"title":"Reducing peak power for coded OFDM systems by multiple symbol mapping","authors":"M. Harada, Takaya Yamamoto, Hiraku Okada, M. Katayama, A. Ogawa","doi":"10.1002/ECJC.10168","DOIUrl":"https://doi.org/10.1002/ECJC.10168","url":null,"abstract":"In this paper, we propose a method for reducing the peak power of the signal for orthogonal frequency division multiplex (OFDM) system in which convolutional code is used for an error-correcting code. In the system, the bit sequence encoded using a convolutional code is mapped onto the multiple symbols which may constrain the peak power of the signal. In the conventional scheme, encoded bits are mapped onto a symbol sequentially. In such a method, the symbols assigned to each subcarrier are mutually uncorrelated and it is therefore difficult to let the symbols have a correlation with other symbols to constrain the peak power of the OFDM signal. In the proposed scheme, the encoded bit sequence is mapped onto the multiple symbols in which each symbol is correlated such as to reduce the peak power of the signal. In this way we are able to keep the peak power of the OFDM signal lower than that of the conventional scheme. For further performance improvement, set partitioning is performed to a set of multiple symbols to increase the Euclidean distance. This approach is made possible by multiple trellis-coded modulation (MTCM) that applies set partitioning to multiple symbols. We evaluate the performance of the proposed scheme in the presence of the effects of nonlinear amplification and show that the proposed scheme is effective for nonlinear amplification. © 2006 Wiley Periodicals, Inc. Electron Comm Jpn Pt 3, 90(3): 67–76, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecjc.10168","PeriodicalId":100407,"journal":{"name":"Electronics and Communications in Japan (Part III: Fundamental Electronic Science)","volume":"29 1","pages":"67-76"},"PeriodicalIF":0.0,"publicationDate":"2007-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88499690","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 2

Improved particle swarm optimization and application to portfolio selection 改进粒子群算法及其在投资组合选择中的应用

Electronics and Communications in Japan (Part III: Fundamental Electronic Science) Pub Date : 2007-03-01 DOI: 10.1002/ECJC.20263

M. Koshino, H. Murata, Haruhiko Kimura

{"title":"Improved particle swarm optimization and application to portfolio selection","authors":"M. Koshino, H. Murata, Haruhiko Kimura","doi":"10.1002/ECJC.20263","DOIUrl":"https://doi.org/10.1002/ECJC.20263","url":null,"abstract":"Particle swarm optimization (PSO) is a population-based stochastic optimization technique, inspired by the social behavior of birds (flocking) or fish (schooling), which is applied to various problems in the optimization of nonlinear systems. The inertia weights approach (IWA) and the constriction factor approach (CFA) are improved methods in PSO. The IWA searches the problem space globally in the early steps, and finally searches locally near the optimal solution. CFA is a method that introduces a new parameter into velocity update equation. \u0000 \u0000 \u0000 \u0000This paper proposes a combination of IWA and CFA (the Inertia Weights Constriction Factor Approach: IWCFA), and PSOrank, whose objective is the ranking of individuals in the population. These two proposed methods are applied to function optimizations and to the portfolio selection problem, which is a typical mathematical problem in securities finance. The results show that the original PSO finds better solutions than the GA, and the proposed method finds better solutions than the original PSO. © 2006 Wiley Periodicals, Inc. Electron Comm Jpn Pt 3, 90(3): 13–25, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecjc.20263","PeriodicalId":100407,"journal":{"name":"Electronics and Communications in Japan (Part III: Fundamental Electronic Science)","volume":"64 1","pages":"13-25"},"PeriodicalIF":0.0,"publicationDate":"2007-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80900490","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 12

All-in-focus photo image creation by wavelet transforms 全聚焦照片图像创建的小波变换

Electronics and Communications in Japan (Part III: Fundamental Electronic Science) Pub Date : 2007-03-01 DOI: 10.1002/ECJC.20236

K. Shirai, K. Nomura, M. Ikehara

引用次数: 2

Recent progress on geometric algorithms for approximating functions: Toward applications to data analysis 函数近似几何算法的最新进展:在数据分析中的应用

Electronics and Communications in Japan (Part III: Fundamental Electronic Science) Pub Date : 2007-03-01 DOI: 10.1002/ECJC.20297

T. Tokuyama

{"title":"Recent progress on geometric algorithms for approximating functions: Toward applications to data analysis","authors":"T. Tokuyama","doi":"10.1002/ECJC.20297","DOIUrl":"https://doi.org/10.1002/ECJC.20297","url":null,"abstract":"Data simplification is an extremely important issue in our current information-oriented society. Normally, a real-world database contains a massive amount of raw data, and when we consider the data as a distribution function, it has fluctuations due to sampling errors, outliers, and/or invalid inputs. Therefore, for data analysis technology such as data mining, it is important to approximate the input data by a simplified function. There are various approaches to function approximation, and functional analytical methods and learning-based techniques are quite popular. Apart from them, computational geometric approach based on optimization using discrete algorithms is widely studied. However, the conventional application of computational geometrical techniques is pattern matching, and to apply them to data analysis, their formulation and optimization criteria must be changed accordingly. Therefore, various difficulties and computational barriers arise, which must be eliminated or avoided. In this paper, we discuss data approximation in computational geometry and describe current trends centered on the author's latest research. © 2006 Wiley Periodicals, Inc. Electron Comm Jpn Pt 3, 90(3): 1–12, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecjc.20297","PeriodicalId":100407,"journal":{"name":"Electronics and Communications in Japan (Part III: Fundamental Electronic Science)","volume":"56 1","pages":"1-12"},"PeriodicalIF":0.0,"publicationDate":"2007-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91216838","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Fractal video coding with the orthogonal transformation 正交变换的分形视频编码

Electronics and Communications in Japan (Part III: Fundamental Electronic Science) Pub Date : 2007-03-01 DOI: 10.1002/ECJC.20248

K. Ohse, M. Nakagawa

引用次数: 0

Performance improvement of vector quantizer with reflection group for uniform distribution on hyperspace 超空间上均匀分布反射群矢量量化器性能的改进

Electronics and Communications in Japan (Part III: Fundamental Electronic Science) Pub Date : 2007-03-01 DOI: 10.1002/ECJC.20261

N. Yamane, Y. Morikawa, Tomohiro Mae, Yuji Takemoto, S. Maki

{"title":"Performance improvement of vector quantizer with reflection group for uniform distribution on hyperspace","authors":"N. Yamane, Y. Morikawa, Tomohiro Mae, Yuji Takemoto, S. Maki","doi":"10.1002/ECJC.20261","DOIUrl":"https://doi.org/10.1002/ECJC.20261","url":null,"abstract":"A two-stage vector quantizer (kaleidoscope vector quantizer: KVQ) using multidimensional symmetry which has a reflection group is proposed as a high-speed vector quantizer (VQ) for vectors following a uniform distribution on a hypersphere. The first-stage VQ of this method is a lattice quantizer on a hypersphere based on a reflection group and plays a central role in achieving higher dimensions and higher rates. The last-stage VQ is a full-search vector quantizer and plays the roles of repartitioning and reforming the Voronoi regions and improving the quantization properties. In this method, the code vectors are assigned only inside the first-stage Voronoi regions. In this paper, a unified-region KVQ is proposed as a method for improving the quantization characteristic in the high dimensions of KVQ. This method also assigns the code vectors of the last-stage VQ to the boundary surfaces of the Voronoi regions of the first-stage VQ. By using this method, the multiple Voronoi regions in the first-stage VQ are merged and repartitioned, and the degree of freedom in the code vector assignment is increased. Simulation tests were conducted on Gaussian vectors and showed that the quantization characteristics equivalent to the full-search VQ were obtained in the range of 16 dimensions and a rate of about 2.5 bits/sample. © 2006 Wiley Periodicals, Inc. Electron Comm Jpn Pt 3, 90(3): 26–35, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecjc.20261","PeriodicalId":100407,"journal":{"name":"Electronics and Communications in Japan (Part III: Fundamental Electronic Science)","volume":"23 1","pages":"26-35"},"PeriodicalIF":0.0,"publicationDate":"2007-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88184820","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Evaluation of smoothed group delay spectrum distance measure in speaker-independent speech recognition 独立说话人语音识别中平滑群延迟频谱距离测度的评价

Electronics and Communications in Japan (Part III: Fundamental Electronic Science) Pub Date : 2007-02-22 DOI: 10.1002/ECJC.4430741005

Taizo Umezaki Member, Harald Singer Member, Fumitada Itakura Member

{"title":"Evaluation of smoothed group delay spectrum distance measure in speaker-independent speech recognition","authors":"Taizo Umezaki Member, Harald Singer Member, Fumitada Itakura Member","doi":"10.1002/ECJC.4430741005","DOIUrl":"https://doi.org/10.1002/ECJC.4430741005","url":null,"abstract":"The smoothed group delay spectrum distance (SGDS) measure is evaluated in speaker-independent recognition experiments. First, the appropriate level of smoothing of the group delay spectrum (GDS) is investigated by adding noise, etc., to the input speech. Then a comparison with the speaker-dependent case is made. An experiment is reported in which, for low amplitude parts of speech (e.g., unvoiced speech), the standard (LPC) distance measure is used in the interframe distance calculation instead of the SGDS distance measure. This method prevents a loss of recognition accuracy due to too strong an emphasis on certain spectral elements and a consistently high recognition accuracy can be achieved. \u0000 \u0000 \u0000 \u0000Finally, evaluate the SGDS distance measure is evaluated where the GDS is represented in the spectral domain as a discrete Fourier transform (DFT) of the LPC coefficients. In comparison to the SGDS which was calculated by weighting the LPC cepstrum co-efficients, computation time and memory space can be reduced without loss of recognition accuracy. Furthermore, a low bit quantization of the GDS is reported and a high recognition rate is achieved with only 32 bits per frame.","PeriodicalId":100407,"journal":{"name":"Electronics and Communications in Japan (Part III: Fundamental Electronic Science)","volume":"21 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2007-02-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83311477","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

On error exponents for a variable size list decoder using the Viterbi algorithm with likelihood testing 基于Viterbi算法和似然检验的可变大小列表解码器的误差指数

Electronics and Communications in Japan (Part III: Fundamental Electronic Science) Pub Date : 2007-02-21 DOI: 10.1002/ecjc.20245

Toshihiro Niinomi, Toshiyasi Matsushima, Shigeichi Hirasawa

引用次数: 0

A performance evaluation of frequency domain blind source separation using close arrangement of directional microphones 使用定向麦克风的紧密排列的频域盲源分离性能评估

Electronics and Communications in Japan (Part III: Fundamental Electronic Science) Pub Date : 2007-02-21 DOI: 10.1002/ecjc.20300

Hiroki Shimizu, Masanori Ito, Yoshinori Takeuchi, Tetsuya Matsumoto, Hiroaki Kudo, Noboru Ohnishi

{"title":"A performance evaluation of frequency domain blind source separation using close arrangement of directional microphones","authors":"Hiroki Shimizu, Masanori Ito, Yoshinori Takeuchi, Tetsuya Matsumoto, Hiroaki Kudo, Noboru Ohnishi","doi":"10.1002/ecjc.20300","DOIUrl":"https://doi.org/10.1002/ecjc.20300","url":null,"abstract":"<p>A performance evaluation of frequency-domain blind source separation (BSS) in a close arrangement of directional microphone is carried out. When a close arrangement is used in time-domain BSS, it is possible to reduce the number of taps necessary for separation while maintaining the same performance as in separation without close arrangement. In this research, from the point of view of the relationship between the number of taps and the separation performance, the calculation time, and the permutation (output order) unique to the frequency domain BSS, a comparison with nonclose arrangement is made. With regard to the calculation time and the permutation error, close arrangement is superior to nonclose arrangement in environments both with and without reverberation. With regard to the separation performance, close arrangement is better than nonclose arrangement in an anechoic chamber but nonclose arrangement is better if there are many taps. If the number of taps is small, close arrangement is superior. © 2007 Wiley Periodicals, Inc. Electron Comm Jpn Pt 3, 90(6): 1– 9, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecjc.20300</p>","PeriodicalId":100407,"journal":{"name":"Electronics and Communications in Japan (Part III: Fundamental Electronic Science)","volume":"90 6","pages":"1-9"},"PeriodicalIF":0.0,"publicationDate":"2007-02-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1002/ecjc.20300","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"71970870","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0