{"title":"Supporting integrated services in wireless networks with space-time block-coded transmissions","authors":"Zhiqiang Liu, A. Stamoulis, G. Giannakis","doi":"10.1109/ACSSC.2000.910763","DOIUrl":"https://doi.org/10.1109/ACSSC.2000.910763","url":null,"abstract":"Integrated services in wireless networks call for a physical layer which can support multirate transmissions and guarantee symbol recovery at the receiver. Multirate transmissions are necessary for data applications with diverse needs in throughput/delay, whereas symbol recovery leads to quality of service guarantees in terms of bit error rate. We develop a multiuser physical layer framework, which can be used in a wireless integrated services architecture. Capitalizing on space-time coding and block transmissions, we show how space-time transmit antenna diversity can provide transmission rates of arbitrarily fine resolution while guaranteeing symbol recovery irrespective of the FIR wireless channel.","PeriodicalId":10581,"journal":{"name":"Conference Record of the Thirty-Fourth Asilomar Conference on Signals, Systems and Computers (Cat. No.00CH37154)","volume":"63 1","pages":"1250-1254 vol.2"},"PeriodicalIF":0.0,"publicationDate":"2000-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88767237","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}
{"title":"Iterative decoding of space-time trellis codes and related implementation issues","authors":"Z. Chi, Zhongfeng Wang, K. Parhi","doi":"10.1109/ACSSC.2000.911018","DOIUrl":"https://doi.org/10.1109/ACSSC.2000.911018","url":null,"abstract":"For high data rate transmission over wireless fading channels, space-time trellis coding techniques can be employed to increase the information capacity of the communication system dramatically. In this paper, we consider the scenario of iterative decoding of concatenated space-time trellis codes and convolutional codes. Extra coding gains in addition to the diversity advantage are shown to be achieved for certain space-time trellis codes transmitted over both quasi-static and fast flat fading channels. A prestudy of related VLSI implementation issues is also presented which includes the finite word-length analysis for serial concatenated space-time trellis turbo decoders and hardware saving strategies.","PeriodicalId":10581,"journal":{"name":"Conference Record of the Thirty-Fourth Asilomar Conference on Signals, Systems and Computers (Cat. No.00CH37154)","volume":"16 1","pages":"562-566 vol.1"},"PeriodicalIF":0.0,"publicationDate":"2000-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82635925","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}
{"title":"A fast constant modulus algorithm for blind equalization","authors":"S. Nelatury, Sathyanarayan S. Rao","doi":"10.1109/ACSSC.2000.910666","DOIUrl":"https://doi.org/10.1109/ACSSC.2000.910666","url":null,"abstract":"The constant modulus (CM) criterion coupled with a gradient search helps in the design of fractionally spaced equalizers. Effective implementation of CM algorithm requires proper choice of the scale factor /spl mu/ called the step size and initialization of equalizer coefficients. Experience reveals that these two determine the convergence rate and final misadjustment. Recently Brown et al. proposed a computationally efficient algorithm, which is a signed error version of CMA. This paper proposes yet another variation of the same and reports faster convergence. The idea is to use variable step size, which increases the convergence rate.","PeriodicalId":10581,"journal":{"name":"Conference Record of the Thirty-Fourth Asilomar Conference on Signals, Systems and Computers (Cat. No.00CH37154)","volume":"52 1","pages":"1010-1013 vol.2"},"PeriodicalIF":0.0,"publicationDate":"2000-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76534354","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}
{"title":"Generalized lapped biorthogonal transforms using lifting steps","authors":"M. Kawada, M. Ikehara","doi":"10.1109/ACSSC.2000.910944","DOIUrl":"https://doi.org/10.1109/ACSSC.2000.910944","url":null,"abstract":"A large class of lapped biorthogonal transforms using lifting steps (LLBT) is presented. The transform coefficients are parametarized as a basic matrix and a series of lifting steps, providing fast, efficient in-place computation of them. Our main motivation of the new transform is its application in image coding. The LLBT has several long overlapped basis functions of the synthesis bank for representing smooth signals to avoid annoying blocking artifacts. The bases of the synthesis bank covering high-frequency bands are constrained to be short to reduce ringing artifacts. Moreover, the analysis bandpass filters provide better stopband attenuation. Comparing to the popular 8/spl times/8 DCT, the LLBT only requires several more additions and shifting operations. However, image coding examples show that the LLBT is far superior to the DCT and 8/spl times/16 LOT in both objective and subjective coding performance.","PeriodicalId":10581,"journal":{"name":"Conference Record of the Thirty-Fourth Asilomar Conference on Signals, Systems and Computers (Cat. No.00CH37154)","volume":"66 1","pages":"197-201 vol.1"},"PeriodicalIF":0.0,"publicationDate":"2000-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72786652","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}
{"title":"Linear unitary precoders for maximum diversity gains with multiple transmit and receive antennas","authors":"Yan Xin, Zhengdao Wang, G. Giannakis","doi":"10.1109/ACSSC.2000.911250","DOIUrl":"https://doi.org/10.1109/ACSSC.2000.911250","url":null,"abstract":"In this paper, we analyze the performance of multiple-transmit/receive antenna systems with linear precoders. From the performance of these systems, we deduce design rules for linear precoders. Following the design rules, we prove the existence and derive linear unitary precoders achieving maximum diversity gain. Compared with existing real precoders, the novel unitary precoders offer the potential of larger coding gains. Simulations illustrate that the unitary precoders can achieve more than 1 dB coding gain over real precoders while they perform comparably to repeated transmissions, that consume larger amounts of bandwidth when two or three transmit antennas are utilized.","PeriodicalId":10581,"journal":{"name":"Conference Record of the Thirty-Fourth Asilomar Conference on Signals, Systems and Computers (Cat. No.00CH37154)","volume":"26 1","pages":"1553-1557 vol.2"},"PeriodicalIF":0.0,"publicationDate":"2000-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73942332","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}
{"title":"Performance of ML rate determination for an IS-95 downlink SIC receiver","authors":"R. Cagley, Kuei-Chiang Lai, J. Shynk","doi":"10.1109/ACSSC.2000.910655","DOIUrl":"https://doi.org/10.1109/ACSSC.2000.910655","url":null,"abstract":"Maximum likelihood (ML) decision rules, such as that presented by Gutierrez, Lee and Mandyam (see. Proc. IEEE 49th Vehicular Technology Conf., Houston, TX, p.417-21, 1999), can be used for rate determination in an IS-95 system to reduce the complexity of the Viterbi decoder. We extend this previous work by determining whether it is beneficial to use rate determination for the successive interference canceller (SIC) in an IS-95 downlink receiver. Assuming certain conditions are met regarding the signal-to-noise ratio (SNR) and the number of received symbols used for rate determination, employing knowledge of bit repetition can decrease the bit error rare (BER) for the corresponding Walsh channels. To further increase the effectiveness of interference cancellation, soft decision decoding can be used instead of a conventional hard decision device. The devices considered here are similar to those of Frey and Reinhardt (see Proc. IEEE 47th Vehicular Technology Conf., Phoenix, AZ, p.155-159, 1997), but they use the knowledge that there can be repeated bits in the IS-95 downlink.","PeriodicalId":10581,"journal":{"name":"Conference Record of the Thirty-Fourth Asilomar Conference on Signals, Systems and Computers (Cat. No.00CH37154)","volume":"142 1","pages":"956-959 vol.2"},"PeriodicalIF":0.0,"publicationDate":"2000-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81747652","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}
{"title":"IFSAR for the rapid terrain visualization demonstration","authors":"B. L. Burns, P. Eichel, W. Hensley, T.J. Kim","doi":"10.1109/ACSSC.2000.910909","DOIUrl":"https://doi.org/10.1109/ACSSC.2000.910909","url":null,"abstract":"The Rapid Terrain Visualization Advanced Concept Technology Demonstration (RTV-ACTD) is designed to \"demonstrate the technologies and infrastructure to meet the Army requirement for rapid generation of digital topographic data to support emerging crisis or contingencies\". The primary sensor for this mission is an interferometric synthetic aperture radar (IFSAR) designed at Sandia National Laboratories. This paper will outline the design of the system and its performance, and show some flight test results. The RTV IFSAR will meet DTED level III and IV specifications by using a multiple-baseline design and high-accuracy differential and carrier-phase GPS navigation. It includes innovative near-real-time DEM production on-board the aircraft. The system is being flown on a deHavilland DHC-7 Army aircraft.","PeriodicalId":10581,"journal":{"name":"Conference Record of the Thirty-Fourth Asilomar Conference on Signals, Systems and Computers (Cat. No.00CH37154)","volume":"153 1","pages":"8-15 vol.1"},"PeriodicalIF":0.0,"publicationDate":"2000-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86669382","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}
{"title":"Design and performance of residue number system based multicarrier CDMA in frequency-selective Rayleigh fading channels","authors":"A. Madhukumar, F. Chin","doi":"10.1109/ACSSC.2000.910640","DOIUrl":"https://doi.org/10.1109/ACSSC.2000.910640","url":null,"abstract":"This paper is concerned with a new method to enhance the bandwidth efficiency of an MC-CDMA system by using a residue number based representation for information symbols. The residues are mapped into a set of orthogonal sequences and are transmitted in parallel. A multicarrier modulation scheme is used for both transmission and reception of residue channels. Appropriate error correction methods are employed for enhancing the performance of the system. The aim of this paper is to discuss the issues involved in the design of an RNS based MC-CDMA system and to evaluate the performance of the system in a frequency selective Rayleigh fading channel.","PeriodicalId":10581,"journal":{"name":"Conference Record of the Thirty-Fourth Asilomar Conference on Signals, Systems and Computers (Cat. No.00CH37154)","volume":"4 1","pages":"884-888 vol.2"},"PeriodicalIF":0.0,"publicationDate":"2000-10-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74499591","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}
{"title":"Speech spectrum modeling applied to spectrum coding and prediction","authors":"J. Lindblom, J. Samuelsson","doi":"10.1109/ACSSC.2000.911241","DOIUrl":"https://doi.org/10.1109/ACSSC.2000.911241","url":null,"abstract":"In this work, the speech spectrum source is modeled. The spectrum is represented by the cepstral coefficients resulting from linear prediction analysis of speech. The models are Gaussian mixture densities, estimated iteratively using two expectation maximization type algorithms. The contribution is an investigation of the algorithms using theoretical measures well as practical applications. The applications are spectrum coding and prediction. Some low-dimensional modeling examples, illustrating the behavior of the two algorithms graphically are given. One of the algorithms has the bounded support issue of the source incorporated in its update equations, resulting in improved modeling accuracy.","PeriodicalId":10581,"journal":{"name":"Conference Record of the Thirty-Fourth Asilomar Conference on Signals, Systems and Computers (Cat. No.00CH37154)","volume":"63 5 1","pages":"1502-1506 vol.2"},"PeriodicalIF":0.0,"publicationDate":"2000-10-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77655930","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}
{"title":"Low-memory, fixed-latency Huffman encoder for unbounded-length codes","authors":"R. Freking, K. Parhi","doi":"10.1109/ACSSC.2000.910670","DOIUrl":"https://doi.org/10.1109/ACSSC.2000.910670","url":null,"abstract":"The Huffman compression algorithm makes reference to a binary tree abstraction that can be employed directly as a data structure for decoding. Unfortunately, the same convenient arrangement has heretofore not served the encoding task. In this paper, the tree structure is revived in an enhanced form that allows encoding to progress naturally from root to leaf. Because this solution is tree based, codewords are not subject to length limitation. Yet, in marked contrast with other unbounded encoders, memory outlay is fixed by the size of the alphabet. Moreover this storage expense is low in comparison with non-tree-based solutions. Also unlike previous tree structures, no post-encoding reversal is demanded resulting in constant-latency operation regardless of codeword length. Furthermore, only simple addition operators are required at each step. Despite its advantages, implementation is uncomplicated and codebook formatting is trivial.","PeriodicalId":10581,"journal":{"name":"Conference Record of the Thirty-Fourth Asilomar Conference on Signals, Systems and Computers (Cat. No.00CH37154)","volume":"1 1","pages":"1031-1034 vol.2"},"PeriodicalIF":0.0,"publicationDate":"2000-10-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79775911","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}