{"title":"Steady-state analysis of the multistage CM array for correlated signals","authors":"A. Mathur, A. V. Keerthi, J. Shynk","doi":"10.1109/ACSSC.1995.540642","DOIUrl":"https://doi.org/10.1109/ACSSC.1995.540642","url":null,"abstract":"A steady-state analysis of the multistage constant modulus (CM) array is presented for the case of correlated source signals. Using a Wiener model for the converged adaptive algorithms, it is demonstrated that because of the cascade structure, signal cross-correlation results in \"phantom\" sources. The resulting \"leakage\" in the signal cancellers between stages causes an increase in the minimum mean-square error. A parallel implementation is discussed that overcomes this loss in performance.","PeriodicalId":171264,"journal":{"name":"Conference Record of The Twenty-Ninth Asilomar Conference on Signals, Systems and Computers","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130257563","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":"On the re-quantization of data to implement high-order narrow-band filters using reconfigurable logic","authors":"C. Dick, F. Harris","doi":"10.1109/ACSSC.1995.540918","DOIUrl":"https://doi.org/10.1109/ACSSC.1995.540918","url":null,"abstract":"This paper addresses the problem of implementing narrow-band FIR filters using FPGAs. A method based on re-quantization of the input data stream using a sigma-delta modulator is presented. The reduced bit length representation of the re-quantized input samples removes the requirement for a full multiplier in the filter hardware. The filtering technique is described and implementation results using a Xilinx XC4010 FPGA are presented. Using a bit-serial approach, a 100 tap narrow-band filter operating at a sample rate of 1.56 MHz has been developed. A 20 tap bit-parallel filter can be accommodated in one XC4010PG191-4 and operates at a sample rate of 22.6 MHz.","PeriodicalId":171264,"journal":{"name":"Conference Record of The Twenty-Ninth Asilomar Conference on Signals, Systems and Computers","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129471789","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":"Zero input behavior of fixed-point digital filters in delta-operator representation","authors":"P. Bauer, R. Castaneda, K. Premaratne","doi":"10.1109/ACSSC.1995.540844","DOIUrl":"https://doi.org/10.1109/ACSSC.1995.540844","url":null,"abstract":"This paper analyzes the zero input behavior of digital filters in delta-operator representation. It is shown that regardless of the quantization and precision scheme, delta-operator based digital filters show very poor zero-convergence. Under zero input conditions the state trajectory typically terminates in a non-zero equilibrium point. The geometry of the arising deadbands are derived and lower as well as upper bounds on the limit cycle amplitudes are obtained. The analysis is conducted in the state space and is independent of the form of the system matrix. The result applies to all commonly used arithmetic schemes and precision options.","PeriodicalId":171264,"journal":{"name":"Conference Record of The Twenty-Ninth Asilomar Conference on Signals, Systems and Computers","volume":"34 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129605974","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":"Cramer-Rao bounds for target angle and Doppler estimation with space-time adaptive processing radar","authors":"J. Ward","doi":"10.1109/ACSSC.1995.540889","DOIUrl":"https://doi.org/10.1109/ACSSC.1995.540889","url":null,"abstract":"Space-time adaptive processing (STAP) can substantially improve airborne radar performance in environments with interference (clutter and/or jamming). This paper considers target parameter estimation with the STAP radar. The maximum-likelihood estimator for target angle and Doppler is reviewed. Cramer-Rao bounds for target angle and Doppler estimation accuracy are derived for an arbitrary interference scenario. These bounds show that in clutter, angle accuracy depends on the target Doppler and vice-versa. They are useful for quantifying the best-case degradation in estimator accuracy due to interference, and for determining the fractions of the Doppler space and coverage sector over which a specified level of accuracy can be achieved.","PeriodicalId":171264,"journal":{"name":"Conference Record of The Twenty-Ninth Asilomar Conference on Signals, Systems and Computers","volume":"13 1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130863164","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 strategies for the final adder in a parallel multiplier","authors":"P. Stelling, V. Oklobdzija","doi":"10.1109/ACSSC.1995.540616","DOIUrl":"https://doi.org/10.1109/ACSSC.1995.540616","url":null,"abstract":"In this paper we address the problem of adding two n-bit numbers when the bit arrival times are arbitrary (but known in advance). In particular we address a simplified version of the problem where the input arrival times for the i/sup th/ significant bits of both addends are the same, and the arrival times t/sub i/ have a profile of the form: t/sub 0//spl les/t/sub 1//spl les/.../spl les/t/sub k/=t/sub k+1/=...=t/sub p/>t/sub p+1//spl ges/.../spl ges/t/sub n-1/. This profile is important because it matches the signal arrival time profile of the reduced partial products in a parallel multiplier before they are summed in the final adder. In this paper we present a design strategy specific to arrival time profiles generated by partial product reduction trees constructed by optimal application of the Three Dimensional Method presented by V.G. Oklobdzija et al. (1995). This strategy can be used to obtain adders for any arrival time profile that matches the above form, as well as a broad class of arrival time profiles where even greater variation in the input times is allowed. Finally, we show that our designs significantly outperform the standard adder designs for the uniform signal arrival profile, yielding faster adders that (for these profiles) are also simpler and use fewer gates.","PeriodicalId":171264,"journal":{"name":"Conference Record of The Twenty-Ninth Asilomar Conference on Signals, Systems and Computers","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128661012","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":"The star multiplier","authors":"E. de Angel, A. Chowdhury, E. Swartzlander","doi":"10.1109/ACSSC.1995.540619","DOIUrl":"https://doi.org/10.1109/ACSSC.1995.540619","url":null,"abstract":"This paper presents the architecture of a new high speed parallel multiplier. A novel architecture based on two ring structures and the modified-Booth (1951) algorithm achieve high speed multiplications with a significant reduction in hardware. The 32 by 32 bit star multiplier has been designed in a 0.6 /spl mu/m CMOS technology and presents a multiplication time of 17.5 ns.","PeriodicalId":171264,"journal":{"name":"Conference Record of The Twenty-Ninth Asilomar Conference on Signals, Systems and Computers","volume":"46 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128682722","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":"Algorithms for EO sensor SNR enhancement and smoothing","authors":"D. L. Webb, L. Hung, D. Elliott","doi":"10.1109/ACSSC.1995.540648","DOIUrl":"https://doi.org/10.1109/ACSSC.1995.540648","url":null,"abstract":"Electro-optical (EO) sensor systems in surveillance and seeker applications demand the highest possible signal-to-noise ratio (SNR) and spatial resolution. This paper introduces algorithms that increase the SNR and spatial resolution for a 2D focal plane array that has a high frame rate and whose field-of-view moves around within a field-of-regard of the scene being viewed. Predicted performance and simulation results for a particular implementation of these algorithms indicate an RMS SNR gain factor of over 40 for relatively low computational cost.","PeriodicalId":171264,"journal":{"name":"Conference Record of The Twenty-Ninth Asilomar Conference on Signals, Systems and Computers","volume":"43 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121657437","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":"Adaptive echo cancellation using statistical shaping","authors":"A. Zerguine, C. Cowan, M. Bettayeb","doi":"10.1109/ACSSC.1995.540593","DOIUrl":"https://doi.org/10.1109/ACSSC.1995.540593","url":null,"abstract":"This article presents a novel structure for bulk delay estimation in long echo cancellers which reduces the amount of excess error considerably. The miscalculation of the delay between the near end and the far end sections is one of the main causes of the excess error. Two analyses, based on the least mean square algorithm, are presented where a certain shape for the transitions (at the end of the near end and at the beginning of the far end sections) is considered. Transient and steady-state behavior and convergence conditions are studied, as well as a comparison between the algorithms developed for each transition. Simulation results agree well with theoretical derivations.","PeriodicalId":171264,"journal":{"name":"Conference Record of The Twenty-Ninth Asilomar Conference on Signals, Systems and Computers","volume":"22 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121922114","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":"Use of adaptive segmentation and classification algorithms in satellite imagery","authors":"C. Lindquist, D. A. Tealdi","doi":"10.1109/ACSSC.1995.540922","DOIUrl":"https://doi.org/10.1109/ACSSC.1995.540922","url":null,"abstract":"Use of satellite imagery continues to grow. Development of DSP algorithms for automated analysis is therefore becoming increasingly important. Areas of immediate application are diverse such as agriculture, deforestation, soil erosion, etc. This paper presents adaptive edge algorithms which identify region boundaries and pattern recognition algorithms to classify the regions within these boundaries. An illustrative example using a satellite image of an agricultural area is presented to demonstrate these algorithms.","PeriodicalId":171264,"journal":{"name":"Conference Record of The Twenty-Ninth Asilomar Conference on Signals, Systems and Computers","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121969957","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":"Frame synchronization for PSAM on Rayleigh fading channels","authors":"J. Gansman, M. Fitz, J. Krogmeier","doi":"10.1109/ACSSC.1995.540552","DOIUrl":"https://doi.org/10.1109/ACSSC.1995.540552","url":null,"abstract":"Pilot symbol assisted modulation (PSAM) is a method to reduce the effects of fading in mobile communications by periodically inserting known symbols in the data stream. The receiver uses these pilot symbols to derive its amplitude and phase reference. One aspect of this procedure which has not received much attention in the literature is the method used by the receiver to locate the pilot symbols. This paper satisfies that need by investigating optimum and sub-optimum frame synchronization techniques for the case of an M-QAM data symbol set and a PSK pilot sequence.","PeriodicalId":171264,"journal":{"name":"Conference Record of The Twenty-Ninth Asilomar Conference on Signals, Systems and Computers","volume":"27 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121293001","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}