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1.
The continual demand for increased performance in modern communication and radar systems in terms of increased bandwidths and higher operating frequencies has led to investigation of novel techniques and technologies for analog signal processing. In particular, surface acoustic waves (SAW) have been extensively exploited with great success to this end, but systems requiring bandwidths greater than 500 MHz and center frequencies greater than 1 GHz have pushed SAW devices near the practical physical limit of the technology. A novel technology promising increased bandwidths at higher frequencies is based on magnetostatic waves (MSW) propagating in epitaxial films such as Yttrium Iron Garnet (YIG). These waves can be exploited in devices offering instantaneous bandwidths up to 2.2 GHz at microwave center frequencies from 0.5 to 20 GHz.MSW signal processing technology, based on transversal filtering concepts has been under extensive investigation for the past 10 years. This paper reviews the work that has been done utilizing the MSW technology in conjunction with reflective arrays to achieve practical spectral amplitude and delay modification. 相似文献
2.
Ishak W.S. 《Proceedings of the IEEE. Institute of Electrical and Electronics Engineers》1988,76(2):171-187
Magnetostatic wave (MSW) technology has been under investigation for more than a decade. Using ferrimagnetic films such as liquid-phase epitaxial (LPE) yttrium iron garnet (YIG) films, MSW devices and subsystems offer instantaneous bandwidths of up to 1 GHz at operating frequencies in the microwave bands (0.5-26.5 GHz). Because MSWs travel with velocities two-to-four orders of magnitude slower than electromagnetic waves, compact devices can be built using hybrid and monolithic microwave integrated circuit (MMIC) techniques. These devices include delay lines, dispersive delay lines, filters, resonators, and directional couplers. Subsystems using these devices, such as electronically tunable delay lines channelized filter banks, delay-line discriminators, oscillators, and frequency multipliers can be used for applications in signal identification, control and processing directly at microwave frequencies. An overview of the MSW technology is presented and an assessment of the various devices and subsystems that can be built using thin and thick LPE-YIG films is provided 相似文献
3.
Adam J.D. 《Proceedings of the IEEE. Institute of Electrical and Electronics Engineers》1988,76(2):159-170
The main performance advantage that analog signal-processing devices have over their digital competitors is the ability to operate with wide instantaneous bandwidths and moderately high dynamic ranges at microwave frequencies. Here, applications of magnetostatic wave (MSW) devices that capitalize on these advantages are reviewed. The first area is broadband microwave receivers, which includes frequency channelizers, dispersive delay lines for compressive receivers, delay lines for pulse storage, and frequency-selective limiters. The second area is beamsteering of phased-array antennas by variable time delays. In both cases, the MSW device approaches and applications are discussed with emphasis on the device characteristics and their systems utilization. Where possible, comparisons with other analog signal-processing approaches are given 相似文献
4.
The present paper reviews recent theoretical results, and reports initial experimental results, on the convolution of contra-propagating magnetostatic forward volume waves (MSFVWs), in the form of cw signals or time-limited cw pulses, in an epitaxial yttrium iron garnet (YIG) film. Computations of the convolver bilinearity factorF
int indicate an efficient convolution process over a wide bandwidth, with values ofF
int that are of the same order as, or better than, the reported experimental results for MSW convolution in a YIG cylindrical or plate geometry. The values of Fint determined experimentally are in excellent agreement with theory. These results are of interest to microwave system developers particularly if bandwidths of 1 GHz or larger can be realized in practice. A limiting feature of magnetostatic wave (MSW) convolvers is that the maximum delay time of a delay line that is realizable without excessive insertion loss is in the order of 0.5s. The advantage of MSW convolvers, of course, lies in their ability to perform signal processing directly at microwave frequencies, and in applications such as electronic warfare the advantageously large bandwidths would mitigate the limitations in delay time.This work was supported in part by a contract from the AIL Division of the Eaton Corporation. 相似文献
5.
A recently reported experimental study of microwave tunable oscillators employing narrowband magnetostatic-wave (MSW) delay lines is reviewed. The narrowbanding was achieved by usinglifted transducers with magnetostatic surface waves (MSSWs) which yielded a bandwidth of 10 MHz with an insertion loss of less than 20dB. This approach at delay-line narrowbanding does not work as well with the other MSW wave-types because of increased insertion loss. The mode-hopping problem which beset earlier studies of MSW delay-line oscillators was overcome in the present work but now a different problem arose, viz., frequency jumping, which occurred every time the electrical length of the circuit external to the delay line changed by 360 degrees. A maximum tuning range of about 600 MHz was obtained, with this range limited primarily by the Avantek GaAs FET amplifier that was used whose electrical length was equivalent to about 45 cm of air transmission line. It was concluded that, if the electrical length of the external circuit is sufficiently reduced (ideally made zero), singlemode operation over an octave bandwidth or more is possible. 相似文献
6.
The application of certain prototype devices, already realized in the complementary surface acoustic wave (SAW) and magnetostatic wave (MSW) technologies, is examined in the context of analogue and digital microwave communications equipments. The specifications of Gaussian response IF bandpass filters and satellite channel multiplexing filters are detailed in the context of SAW designs. Extensions of SAW filter technology to the construction of IF remodulating modems incorporating frequency modulated oscillators and discriminators are examined. Stable SAW oscillators are also reviewed in the context of lightweight, rugged, spacequalified local oscillator drives. The application of MSW technology to the design of a group delay equalizer for millimetric waveguide long-haul digital communications equipments is surveyed. Finally, the paper addresses the design of fixed and variable delay lines realized in both technologies, and SAW code generators, for application to path-length equalization and test{ng of high data rate microwave radio relay systems, respectively. 相似文献
7.
《Proceedings of the IEEE. Institute of Electrical and Electronics Engineers》1965,53(10):1428-1437
The low-loss propagation of microwave phonons at room temperature in certain single crystals makes practical the construction of microwave acoustic delay (MAD) lines. The properties of these solid-state units are discussed and compared to those of more conventional microwave delay devices. Various possible applications of solid-state lines are suggested and the present status of these units is reviewed. The dispersive properties of magnetoelastic and magnetostatic wave propagation are also outlined and practical considerations governing their use are discussed. Microwave acoustic delay devices not only offer size and weight advantages over conventional microwave delay lines, but also offer improved performance and in many cases lower cost than the conventional units. 相似文献
8.
The paper presents an electrodynamic analysis of tunable multiport ferrite-dielectric structures with parallel transmission lines of an arbitrary type, coupled through propagating magnetostatic modes of magnetized multilayered ferrite films. The structures are supposed to be excited at one port by an incident electromagnetic wave, and amplitudes and phases of electromagnetic waves at other ports are obtained by an analytical procedure. The model holds for an arbitrary direction of a magnetizing field and describes the interaction of magnetostatic modes in ferrite films of a finite width. The solution is obtained in a self-consistent approach, i.e., a reaction of magnetostatic waves (MSWs) on transducers, which excite them, is taken into account. Derived closed-form expressions for response functions of multiports provide the base for the modeling of a wide class of MSW devices: multichannel adjustable filters and delay lines, directional couplers, frequency-selective power dividers, tunable oscillators and active filters, and multiport resonators. The theory is also valid for the analysis of multi-element, interdigital, and meander MSW transducers. Applications of a general theory are demonstrated for numerical calculations of frequency responses of surface and forward volume MSW filters, delay lines with new types of strip-line transducers (two-port and T-type), and for the analysis of a phenomenon of mutual coupling of transducers in conventional devices. 相似文献
9.
Solid-state delay lines operating at microwave frequencies can provide many advantages over conventional delay techniques. These devices use sound waves or magnetic spin waves to obtain fixed, variable, or dispersive behavior. The size and weight of electromagnetic delay lines, together with inherent high cable loss, are avoided with solid-state units. Pulse compression filters with bandwidths of several hundred MHz have been constructed, and the future promises even greater capabilities. 相似文献
10.
A. D. Fisher 《Circuits, Systems, and Signal Processing》1985,4(1-2):265-284
Magneto-optical devices based on Bragg diffraction of light by magnetostatic waves (MSWs) offer the potential of large time-bandwidth optical signal processing at microwave frequencies of 1 to 20 GHz and higher. A thin-film integrated-optical configuration, with the interacting MSW and guided-optical wave both propagating in a common ferrite layer, is necessary to avoid shape-factor demagnetization effects. The underlying theory of the MSW-optical interaction is outlined, including the development of expressions for optical diffraction efficiency as a function of MSW power and frequency, device geometry, materials properties, and other relevant parameters. Recent experimental observations of anisotropic Bragg diffraction and collinear TETM mode conversion induced by MSWs in yttrium iron garnet (YIG) thin films suggest that high-performance MSW integrated-optical devices are feasible. Diffraction levels as large as 4% (7-mm interaction length) and a modulation dynamic range of 30 db have been demonstrated. Potential signal processing applications are mentioned, including: spectrum analyzers, convolvers/correlators, deflectors, non-reciprocal optical isolators, and tunable narrowband optical filters. Advantages of these MSW-based devices over the analogous acousto-optical devices include: much greater operating frequencies, tuning through the MSW dispersion relation by varying either the rf frequency or the applied bias magnetic field, simple MSW transducer structures (e.g., a single stripline), and the potential for very high diffraction efficiencies. 相似文献
11.
《Microwave Theory and Techniques》1969,17(11):986-997
Needs for nondispersive microwave variable delay devices exist in RADAR, communication, ECM, and test systems. Methods which have been investigated to satisfy these needs are reviewed in this paper. Techniques that employ solid-state microwave acoustic interactions and that have promise of satisfying some of the microwave variable delay requirements are described in detail, and their present capabilities and potential capabilities are discussed. One technique employing magnetoelastic waves is particularly promising and the state of the art of this technique is analyzed thoroughly. 相似文献
12.
Surface-wave components have demonstrated performance capabilities in the VHF/UHF range which are available with no other filtering technique. The major advantages of the filters are their small size, high reliability, low cost, high Q, good reproducibility, temperature stability, wide dynamic range, and linear phase response, as well as special characteristics relevant to specific applications. Surface-acousticwave (SAW) devices are used for bandpass filtering [1], matched filtering for radar pulse compression [2], [3] or spread-spectrum signal processing [4], delay lines [5], and frequency control elements [3], [6]. Within the context of communication systems' applications, this paper reviews the state of the art for SAW components from high-performance fixed-tuned devices to tunable or programmable filters. Major technological advances discussed include unidirectional SAW filters [7] which eliminate bidirectionality loss and simultaneously suppress in-band spurious responses to achieve an insertion loss below 1 dB with a 0.04-dB peak-to-peak ripple. A novel surface-wave sub-system [8] which offers revolutionary signal processing functions through transform processing is also described. 相似文献
13.
Microwave acoustic materials, devices, and applications 总被引:4,自引:0,他引:4
Weigel R. Morgan D.P. Owens J.M. Ballato A. Lakin K.M. Hashimoto K. Ruppel C.C.W. 《Microwave Theory and Techniques》2002,50(3):738-749
This paper surveys applications of acoustic waves in microwave devices. After a general and historical introduction to bulk acoustic waves (BAWs), surface acoustic waves (SAWs), practical wave types, and acoustoelectric transducers, a review is given of technologically important materials for microwave acoustic applications. Following this, we discuss BAW and SAW microwave devices and their technologies. Specifically reviewed are thin-film resonators and filters, transversal filters, and filters for correlative analog signal processing. Finally, an overview of the most important microwave applications is given, along with manufacturing and packaging issues 相似文献
14.
A new element, allowing the mixing of signals in the microwave frequency range is described. Excitation of magnetostatic waves (MSW) in the non-stationary medium has been used to modulate the carrier harmonic signal. The proper choice of the working point allows the higher harmonic products of the output frequency spectrum to be suppressed.<> 相似文献
15.
Liang G.C. Withers R.S. Cole B.F. Garrison S.M. Johansson M.E. Ruby W.S. Lyons W.G. 《Applied Superconductivity, IEEE Transactions on》1993,3(3):3037-3042
The very low microwave surface resistance of high-temperature-superconductor (HTS) thin films allows the realization of microwave devices with performance superior to those made by conventional technology. Superconducting delay lines, for example, have very low propagation loss and dispersion. Long, low-loss, superconducting delay lines on both thinned LaAlO3 and sapphire substrates are presented. Delay lines with 27- and 44-ns delay have been made, for the first time, on 5-cm-diameter 254- and 127-μm-thick LaAlO3 substrates, respectively. The insertion losses at 77 K and 6 GHz are 6 and 16 dB, respectively. Delay lines with 9-ns delay have, for the first time, been produced on M-plane sapphire substrates and demonstrate, at 77 K, an insertion loss of 1.0 dB at 6 GHz. A 2.5%-bandwidth 10 GHz four pole edge-coupled bandpass filter on M-plane sapphire substrates is also reported. The filter has minimum insertion loss of less than 0.5 dB at 9.75 GHz and 71 K 相似文献
16.
《Microwave Theory and Techniques》1986,34(12):1383-1393
The purpose of this paper is to review the status of magnetostatic wave (MSW) resonators and to describe, in detail. the theory of operation of the recently developed straight-edge resonators. These resonators are based on magnetostatic waves propagating in high Q cavities fabricated in thin ferrimagnetic films. The resonance frequency of these resonators can be tuned via a bias magnetic field. The theory of propagation of magnetostatic wave devices in periodic arrays will be briefly described followed by a detailed overview of the different configurations for MSW resonators. Three distinct classes of resonators will be discussed 1) resonators based on array reflectors (deposited metals and etched grooves) will be described in detail; 2) guided-wave ring resonators will be discussed; and 3) the theory of operation and design criteria for the straight-edge resonators will be described. Each class will be evaluated, pointing out the advantages and drawbacks, and whenever applicable, the power handling properties and the phase noise performance will be given. 相似文献
17.
An experimental and theoretical study is presented of the insertion loss of magnetostatic surface wave delay lines. The magnetostatic surface waves are excited by single microstrip transducer and propagate in a delay line consisting of conductor-dielectric-YIG-GGG. The effect of nonuniformity in microstrip current and the effect of finite width of YIG film are included in the theory. An undesired notch seen in the insertion-loss response of the surface-wave delay line in the low-frequency region of the band is explained by the present theory, which includes the finite width of the YIG film 相似文献
18.
Campbell C.K. 《Proceedings of the IEEE. Institute of Electrical and Electronics Engineers》1989,77(10):1453-1484
Surface acoustic wave (SAW) device coverage includes delay lines and filters operating at selected frequencies in the range from about 10 MHz to 11 GHz; modeling with single-crystal piezoelectrics and layered structures; resonators and low-loss filters; comb filters and multiplexers; antenna duplexers; harmonic devices; chirp filters for pulse compression; coding with fixed and programmable transversal filters; Barker and quadraphase coding; adaptive filters; acoustic and acoustoelectric convolvers and correlators for radar, spread spectrum, and packet radio; acoustooptic processors for Bragg modulation and spectrum analysis; real-time Fourier-transform and cepstrum processors for radar and sonar; compressive receivers; Nyquist filters for microwave digital radio; clock-recovery filters for fiber communications; fixed-, tunable-, and multimode oscillators and frequency synthesizers; acoustic charge transport (ACT); and other SAW devices for signal processing on gallium arsenide. Shallow bulk acoustic wave (SBAW) device applications include gigahertz delay lines, surface-transverse-wave resonators employing energy-trapping gratings and oscillators with enhanced performance and capability 相似文献
19.
《Optical Fiber Technology》2000,6(2):91-108
Methods for wideband photonic signal processing using fiber delay lines and Bragg grating sampling elements are described. These processors provide new capabilities for the realization of high time-bandwidth operation and high resolution performance. Multiple wavelength techniques with discrete and chirped Bragg gratings are described, which have high capacity signal processing functions using dense parallel signal processing techniques. Both fixed and tunable or reconfigurable processors using wavelength control to change the sampling time are discussed. A range of grating-based signal processors, including high Q microwave filtering, frequency discriminators, widely tunable filters, fast and adaptive signal correlators, and true-time delay beamforming in phased array antennas are described. 相似文献