Absfmcf-Bounds on the accuracy of estimates of the center frequency of an ultrasound signal are considered. In particular the Cramer-Rao lower bound to the variance of any unbiased estimatnr is calculated. This lower bound is then compared with a simple zero-counting method. An example utilizing typical ultrasound parameters is worked. It is shown that this easily computable estimator performs surprisingly well.
{"title":"Optimal Center-Frequency Estimation for Back-Scattered Ultrasound Pulses","authors":"R. K. Bahr, J. Bucklew, S. Flax","doi":"10.1109/T-SU.1985.31669","DOIUrl":"https://doi.org/10.1109/T-SU.1985.31669","url":null,"abstract":"Absfmcf-Bounds on the accuracy of estimates of the center frequency of an ultrasound signal are considered. In particular the Cramer-Rao lower bound to the variance of any unbiased estimatnr is calculated. This lower bound is then compared with a simple zero-counting method. An example utilizing typical ultrasound parameters is worked. It is shown that this easily computable estimator performs surprisingly well.","PeriodicalId":371797,"journal":{"name":"IEEE Transactions on Sonics and Ultrasonics","volume":"107 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1985-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124939180","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}
Abstrnct-In surface-acoustic-wave (SAW) convolver4 used to process long-duration waveforms, the output plate electrode behaves like a lossy transmission line and the effects of electromagnetic delay and electrode resistivity must be taken into account in evaluating convnlver characteristics. These effects are characterized by a spatial uniformity or weighting function, which results in a device output that is a weighted, instead of a t rue, convolution. When a single tap is used to extract signal from a long cnnvolver, the amplitude and phase nonuniformities due to electromagnetic effects degrade the convolver performance. A common way of overcoming this spatial uniformity problem is to use many taps to extract the output signal. Although it reduces the effect of nonuniformities to acceptable levels, the multiple tapping solution can increase device insertion loss and decrease bandwidth unless special output-matching netwnrks are incorporated. These transmission line effects can be modeled by a simple equivalent circuit which makes it possible to calculate the spatial uniformity functions fnr both single and multiply tapped cnnvolver geometries. Using realistic values for parasitic elements introduced hy honding pads and wires, a multisection circuit for the multiply tapped structure is assembled and analyzed using ac circuit analysis programs. The characteristics of multiply tapped convolvers are presented with particular emphasis on spatial uniformity, system bandwidth, and insertion loss. Examples of the computer-aided design of appropriate output-matching networks which maximize handwidth and output level a r e given.
{"title":"Spatial Uniformity and Broadband Matching in Multiply Tapped SAW Convolvers","authors":"E. Adler","doi":"10.1109/T-SU.1985.31652","DOIUrl":"https://doi.org/10.1109/T-SU.1985.31652","url":null,"abstract":"Abstrnct-In surface-acoustic-wave (SAW) convolver4 used to process long-duration waveforms, the output plate electrode behaves like a lossy transmission line and the effects of electromagnetic delay and electrode resistivity must be taken into account in evaluating convnlver characteristics. These effects are characterized by a spatial uniformity or weighting function, which results in a device output that is a weighted, instead of a t rue, convolution. When a single tap is used to extract signal from a long cnnvolver, the amplitude and phase nonuniformities due to electromagnetic effects degrade the convolver performance. A common way of overcoming this spatial uniformity problem is to use many taps to extract the output signal. Although it reduces the effect of nonuniformities to acceptable levels, the multiple tapping solution can increase device insertion loss and decrease bandwidth unless special output-matching netwnrks are incorporated. These transmission line effects can be modeled by a simple equivalent circuit which makes it possible to calculate the spatial uniformity functions fnr both single and multiply tapped cnnvolver geometries. Using realistic values for parasitic elements introduced hy honding pads and wires, a multisection circuit for the multiply tapped structure is assembled and analyzed using ac circuit analysis programs. The characteristics of multiply tapped convolvers are presented with particular emphasis on spatial uniformity, system bandwidth, and insertion loss. Examples of the computer-aided design of appropriate output-matching networks which maximize handwidth and output level a r e given.","PeriodicalId":371797,"journal":{"name":"IEEE Transactions on Sonics and Ultrasonics","volume":"2021 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1985-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127094823","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}
Convolver and correlator devices are key components for spread-spectrum communication systems. These devices are employed most effectively as matched filter elements to improve the signal-to-noise ratio in spread-spectrum communication systems. The basic design, fabrication, and operaling parameters of a monolithic SAW convolver/ correlator on a silicon semiconductor substrate are described. Both passive convolvers, such as metal-zinc oxide semiconductor structures, and active convolvers, such as PI-FET will be included. By use of a zinc oxide (ZnO) piezoelectric thin film material, both acoustoeleclric SAW and semiconductor electronic device components may be fabricated on the same monolithic substrate. The development of such monolithic signal processors is expected to result in very large time-bandwidth devices monolithically integrated on a single substrate compatible with low cost batch fabrication techniques. The device characterization is mainly performed by using an HP-8505 automatic network analyzer system controlled by an HP-9845 computer. Using this ystem, the transduction properties of ZnO/Si structures were evaluated. State-ofthe-art SAW monolithic technology is discussed for devices as long as 1.6 in and acoustic delays of 10 p , which are successfully fabricated on 3-in Si wafers. These large-scale devices are operating at 340 MHz and demonstrate insertion loss better than 35 dB at a feedthrough level of 90 dB, resulting in a dynamic range of better than 55 dB.
{"title":"Large-Scale Monolithic SAW Convolver/Correlator on Silicon","authors":"M. E. Motamedi, M. Kilcoyne, R.K. Asaourian","doi":"10.1109/T-SU.1985.31649","DOIUrl":"https://doi.org/10.1109/T-SU.1985.31649","url":null,"abstract":"Convolver and correlator devices are key components for spread-spectrum communication systems. These devices are employed most effectively as matched filter elements to improve the signal-to-noise ratio in spread-spectrum communication systems. The basic design, fabrication, and operaling parameters of a monolithic SAW convolver/ correlator on a silicon semiconductor substrate are described. Both passive convolvers, such as metal-zinc oxide semiconductor structures, and active convolvers, such as PI-FET will be included. By use of a zinc oxide (ZnO) piezoelectric thin film material, both acoustoeleclric SAW and semiconductor electronic device components may be fabricated on the same monolithic substrate. The development of such monolithic signal processors is expected to result in very large time-bandwidth devices monolithically integrated on a single substrate compatible with low cost batch fabrication techniques. The device characterization is mainly performed by using an HP-8505 automatic network analyzer system controlled by an HP-9845 computer. Using this ystem, the transduction properties of ZnO/Si structures were evaluated. State-ofthe-art SAW monolithic technology is discussed for devices as long as 1.6 in and acoustic delays of 10 p , which are successfully fabricated on 3-in Si wafers. These large-scale devices are operating at 340 MHz and demonstrate insertion loss better than 35 dB at a feedthrough level of 90 dB, resulting in a dynamic range of better than 55 dB.","PeriodicalId":371797,"journal":{"name":"IEEE Transactions on Sonics and Ultrasonics","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1985-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125511893","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}
A recently reported theory is reviewed for the convolution of contra-propagating magnetostatic forward-volume waves (MSFVW) in an epitaxial yttrium iron garnet (YIG) film, which are in the form of continuous-wave signals or time-limited continuous-wave pulses. Initial experimental results on the convolution of contra-propagating MSFVW’s as well as of contra-propagating magnetostatic backward-volume waves (MSBVW) are reported. Computations of the MSFVW internal convolver hilinearity factor Fin, indicate an efficient convolution process over a wide bandwidth. The experimentally determined values of MSFVW Fint are in excellent agreement with theory. The present results will interest microwave system developers in electronic warfare and other areas, particularly if bandwidths of 1 GHz or larger can be realized in practice, even though magnetostatic-wave (MSW) delay lines, in comparison to SAW delay lines, are severely limited in terms of the maximum delay time that is realizable without excessive insertion loss, which is on the order of 0.5 CS. The reason for the interest in MSW convolvers (as, indeed, for the entire MSW technology) lies, of course, in the ability that is afforded for performing signal processing directly at microwave frequencies.
{"title":"Convolution with Magnetostatic Waves in YIG Films","authors":"J. Parekh, Hang-Sheng Tuan, K. Chang","doi":"10.1109/T-SU.1985.31653","DOIUrl":"https://doi.org/10.1109/T-SU.1985.31653","url":null,"abstract":"A recently reported theory is reviewed for the convolution of contra-propagating magnetostatic forward-volume waves (MSFVW) in an epitaxial yttrium iron garnet (YIG) film, which are in the form of continuous-wave signals or time-limited continuous-wave pulses. Initial experimental results on the convolution of contra-propagating MSFVW’s as well as of contra-propagating magnetostatic backward-volume waves (MSBVW) are reported. Computations of the MSFVW internal convolver hilinearity factor Fin, indicate an efficient convolution process over a wide bandwidth. The experimentally determined values of MSFVW Fint are in excellent agreement with theory. The present results will interest microwave system developers in electronic warfare and other areas, particularly if bandwidths of 1 GHz or larger can be realized in practice, even though magnetostatic-wave (MSW) delay lines, in comparison to SAW delay lines, are severely limited in terms of the maximum delay time that is realizable without excessive insertion loss, which is on the order of 0.5 CS. The reason for the interest in MSW convolvers (as, indeed, for the entire MSW technology) lies, of course, in the ability that is afforded for performing signal processing directly at microwave frequencies.","PeriodicalId":371797,"journal":{"name":"IEEE Transactions on Sonics and Ultrasonics","volume":"34 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1985-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121850529","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}
Avantages des dispositifs acoustoelectriques a ondes acoustiques de surface utilisant une couche piezoelectrique de ZnO deposee sur un substrat semiconducteur
利用半导体衬底上的压电氧化锌层的表面声波电声器件的优点
{"title":"Zinc Oxide Films for Acoustoelectric Device Applications","authors":"F. Hickernell","doi":"10.1109/T-SU.1985.31645","DOIUrl":"https://doi.org/10.1109/T-SU.1985.31645","url":null,"abstract":"Avantages des dispositifs acoustoelectriques a ondes acoustiques de surface utilisant une couche piezoelectrique de ZnO deposee sur un substrat semiconducteur","PeriodicalId":371797,"journal":{"name":"IEEE Transactions on Sonics and Ultrasonics","volume":"65 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1985-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115290253","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}
Surface acoustic wave (SAW) convolvers are capable of performing programmable matched filtering with the desirable properties of large processing gain, good dynamic range, broad bandwidth, small size and weight, and low power requirements. Equally powerful are the SAW-based modulators, which produce the desired pseudo-random code sequence for secure transmission in a spread-spectrum system. The SAW filter provides precise reproducible pulse shaping of the coded waveform with the same advantages of the convolver. It is very important as spectrum space becomes more crowded to optimize the spectral efficiency of transmitted information. Quadrature phase (QPSK) and minimum phase shift keying (MSK) are the two most popular quadrature modulation schemes. A new modulation technique that is composed of several amplitude-weighted QPSK signals (AWQPSK) and exhibits better bandwidth efficiency than QPSK or MSK is introduced. System analysis and performance parameters are presented for evaluation. A SAW modulator implementation is discussed and proposed.
{"title":"Amplitude-Weighted Quadrature Phase Shift Keying Using SAW Technology","authors":"M. Belkerdid, D. Malocha","doi":"10.1109/T-SU.1985.31663","DOIUrl":"https://doi.org/10.1109/T-SU.1985.31663","url":null,"abstract":"Surface acoustic wave (SAW) convolvers are capable of performing programmable matched filtering with the desirable properties of large processing gain, good dynamic range, broad bandwidth, small size and weight, and low power requirements. Equally powerful are the SAW-based modulators, which produce the desired pseudo-random code sequence for secure transmission in a spread-spectrum system. The SAW filter provides precise reproducible pulse shaping of the coded waveform with the same advantages of the convolver. It is very important as spectrum space becomes more crowded to optimize the spectral efficiency of transmitted information. Quadrature phase (QPSK) and minimum phase shift keying (MSK) are the two most popular quadrature modulation schemes. A new modulation technique that is composed of several amplitude-weighted QPSK signals (AWQPSK) and exhibits better bandwidth efficiency than QPSK or MSK is introduced. System analysis and performance parameters are presented for evaluation. A SAW modulator implementation is discussed and proposed.","PeriodicalId":371797,"journal":{"name":"IEEE Transactions on Sonics and Ultrasonics","volume":"45 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1985-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125391372","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}
Une nouvelle structure de ligne a retard et les nouveaux concepts d'interaction entre le semiconducteur et les ondes acoustiques de surface offrent une methode de caracterisation des surfaces et interfaces de semiconducteurs. Le signal analyse est la tension acoustoelectrique transversale, dont la constante de temps en regime transitoire est reliee a la duree de vie des porteurs et a la vitesse de generation des porteurs en surface
{"title":"Transient Behavior of Transverse Acoustoelectric Voltage and Nondestructive Characterization of Semiconductor Surfaces","authors":"B. Davari, P. Das","doi":"10.1109/T-SU.1985.31662","DOIUrl":"https://doi.org/10.1109/T-SU.1985.31662","url":null,"abstract":"Une nouvelle structure de ligne a retard et les nouveaux concepts d'interaction entre le semiconducteur et les ondes acoustiques de surface offrent une methode de caracterisation des surfaces et interfaces de semiconducteurs. Le signal analyse est la tension acoustoelectrique transversale, dont la constante de temps en regime transitoire est reliee a la duree de vie des porteurs et a la vitesse de generation des porteurs en surface","PeriodicalId":371797,"journal":{"name":"IEEE Transactions on Sonics and Ultrasonics","volume":"175 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1985-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115579689","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}
S. Minagawa, T. Okamoto, T. Niitsuma, K. Tsubouchi, N. Mikoshiba
A detailed design theory of the Sezawa wave convolver is developed, and the fabrication of a high-efficiency convolver using a ZnO-Si0,-Si structure is discussed. The important points to improve the efficiency are 1) an optimum choice of SAW propagation direction on the Si substrate, 2) an optimum design of the resistivily of the Si epitaxial layer and ZnO film thickness, and 3) an improvement for low- ering SAW propagation lsos and resistance of output circuit. The ex- periments were carried out for two specifications each with a 20-mm and 40-mm gate length. The highest efficiency (F,) of -35 dBm was obtained in the gate length of 20 mm while the time-bandwidth product (ET) was 107. The highest ET product of 227 was obtained in the gate length of 40 mm, while F, was -47.5 dBm. At the present time, the maximum available ETproduct is less than 320 due to the group velocity dispersion.
{"title":"Efficient ZnO-SiO2-Si Sezawa Wave Convolver","authors":"S. Minagawa, T. Okamoto, T. Niitsuma, K. Tsubouchi, N. Mikoshiba","doi":"10.1109/T-SU.1985.31650","DOIUrl":"https://doi.org/10.1109/T-SU.1985.31650","url":null,"abstract":"A detailed design theory of the Sezawa wave convolver is developed, and the fabrication of a high-efficiency convolver using a ZnO-Si0,-Si structure is discussed. The important points to improve the efficiency are 1) an optimum choice of SAW propagation direction on the Si substrate, 2) an optimum design of the resistivily of the Si epitaxial layer and ZnO film thickness, and 3) an improvement for low- ering SAW propagation lsos and resistance of output circuit. The ex- periments were carried out for two specifications each with a 20-mm and 40-mm gate length. The highest efficiency (F,) of -35 dBm was obtained in the gate length of 20 mm while the time-bandwidth product (ET) was 107. The highest ET product of 227 was obtained in the gate length of 40 mm, while F, was -47.5 dBm. At the present time, the maximum available ETproduct is less than 320 due to the group velocity dispersion.","PeriodicalId":371797,"journal":{"name":"IEEE Transactions on Sonics and Ultrasonics","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1985-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131300003","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}
Absfmct-The design of acoustoelectric memory correlators with several input channels is described. Channel isolation is provided by holographic phase cancellation of angularly offset beams. An analysis is given of the cross correlation between wide-band signals on adjacent beams, which are aperture-profiled to improve the isolation. Beam-protiling is obtained by a combination of a multistrip fan-out structure and an interdigital transducer. The factors contributing to the power efficiency and its frequency dependence are analyzed in some detail. The design and experimental results obtained with an eight-channel device with a 40-MHz bandwidth and a 6.5-ps delay in each channel are presented. The experimental work used a separated-medium configuration with Schottky diodes on silicon that was coupled capacitively to a surface-acoustic-wave lithium-niobate delay line through an air gap.
{"title":"Memory Correlators with Multiple Input Channels","authors":"K. Ingebrigtsen, A. Rønnekleiv, S. Stueflotten","doi":"10.1109/T-SU.1985.31654","DOIUrl":"https://doi.org/10.1109/T-SU.1985.31654","url":null,"abstract":"Absfmct-The design of acoustoelectric memory correlators with several input channels is described. Channel isolation is provided by holographic phase cancellation of angularly offset beams. An analysis is given of the cross correlation between wide-band signals on adjacent beams, which are aperture-profiled to improve the isolation. Beam-protiling is obtained by a combination of a multistrip fan-out structure and an interdigital transducer. The factors contributing to the power efficiency and its frequency dependence are analyzed in some detail. The design and experimental results obtained with an eight-channel device with a 40-MHz bandwidth and a 6.5-ps delay in each channel are presented. The experimental work used a separated-medium configuration with Schottky diodes on silicon that was coupled capacitively to a surface-acoustic-wave lithium-niobate delay line through an air gap.","PeriodicalId":371797,"journal":{"name":"IEEE Transactions on Sonics and Ultrasonics","volume":"354 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1985-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114157076","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}
Stephen Wanuga, the Editor in Chief of the IEEE Transactions on Sonics and Ultrasonics for nearly 15 years, has decided to step down. He will be replaced by William D. O'Brien, Jr.
{"title":"Announcement [EIC steps down]","authors":"T. Meeker","doi":"10.1109/T-SU.1985.31643","DOIUrl":"https://doi.org/10.1109/T-SU.1985.31643","url":null,"abstract":"Stephen Wanuga, the Editor in Chief of the IEEE Transactions on Sonics and Ultrasonics for nearly 15 years, has decided to step down. He will be replaced by William D. O'Brien, Jr.","PeriodicalId":371797,"journal":{"name":"IEEE Transactions on Sonics and Ultrasonics","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1985-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114445733","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}
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