Technology for the United States Navy and Marine Corps, 2000-2035: Becoming a 21st-Century Force Volume 2: Technology (1997) / Chapter Skim
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4 SENSORS
4 SENSORS
Pages 104-180
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From page 104... ...
4 Sensors INTRODUCTION Although many factors contribute to the success of any military operation, it has long been recognized that information is one of the most important information in many different forms and acquired on many different time scales. Information During conflict situations several different kinds of information come into play.
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From page 105... ...
In all cases, whatever the sensor, an interaction between the sensor and its local physical environment results in the generation of some kind of signal, generally a form of electrical response of the sensor's physics, chemistry, and biology to the physics, chemistry, and biology of the outside world. The interpretation of these sensor signals through signal processing, data fusion, and the like leads ultimately to the extraction of the desired information.
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Physical Phenomena The range of sensor types of interest to naval forces is enormous. Box 4.1 lists the basic physical phenomena that underlie the types of relevant sensors.
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From page 107... ...
Sensor Interface with the External World The first thing that must be considered is the interface between the sensor and the physical phenomena to be sensed. For some classes of sensors, e.g., chemical or biological sensors, physical samples of atoms or molecules or chunks of material must be collected and inserted into the sensor's detection mechanism.
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From page 108... ...
The details of the sensor implementations can be altered by the designer, but the outside world' s physics is whatever it is and is not under the control of the designer or the sensor. When sensor performance capabilities are projected into the near and far future, the interface constraint remains invariant e.g., although it will be possible, with time, to compress more and more digital and computing capabilities into ever-decreasing volumes, the dimensions and characteristics of the radar aperture needed for a given task will remain basically the same.
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From page 109... ...
Information Extraction The stream of digital data emerging from each individual sensor element, e.g., each pixel of an IR focal plane array or each receive element of a phased array radar, must be assembled, stored, processed to extract the desired information, and communicated to a user sometimes a human and sometimes another mechanical/electronic device that can use this information for guidance and control or some other purpose. Progress in all aspects of computer technology, and particularly algorithm technology, will translate directly into improved, more capable sensors.
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From page 110... ...
For example, temperature or atmospheric pressure sensors can supply inputs for short- and long-term weather prediction, whereas acoustic sensors mounted on rotating machinery can provide evidence of bearing wear or imminent gear failure, thus triggering needed repair and maintenance procedures. In short, naval forces are heavily dependent on the use of sensors today, and the future seems to promise even broader use of sensors as the technology continues to evolve toward more capable performance and the demand for more and better information escalates.
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From page 111... ...
Solid-state Technology The most obvious overall trend of significance in technology today is solidstate technology's dominant role in both analog and digital electronics. Today's digital circuits are solid-state the semiconductor transistor, in one form or another, is the workhorse of the industry and the foundation for all practical digital IC implementations.
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From page 112... ...
Today, magnetrons are still cheaper than the equivalent power transistor, but that may not last as solid-state electronics continue simultaneously to improve in performance and fall in price. Given this widespread trend, it seems likely that all future advanced sensors will process their detected electrical signals with some form of solid-state circuitry.
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From page 113... ...
These kinds of ADC/ DAC capabilities, combined with accelerating computational capabilities, will permit the implementation of advanced adaptive processing algorithms, e.g., digital beamforming and space-time adaptive processing (STAP) , and effective ATR algorithms, as well as the exploitation of multisensor data fusion techniques.
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From page 114... ...
This kind of implementation of sensors suggests the possibilities of higher overall performance in surveillance, for example, through adaptive, autonomous spatial repositioning of the individual sensors. The development of single, small, flying sensors of this sort is already under way.
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From page 115... ...
On the other hand, significant increases in computational memory and throughput are required and offer additional challenges on the path to achieving high performance and affordability. Multifunctional Configurations The final technology trend of significance to the future growth of advanced sensors and sensor systems is the broad and growing interest in the implementation of multifunctional configurations that is, sensors capable of performing several different functions via shared hardware.
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From page 116... ...
CRITICAL COMMON TECHNOLOGIES The discussion above of the generic sensor model identifies five key technologies as common to all modern sensors and sensor systems and as absolutely critical to their performance potential. Understanding the current state of the art of these individual technical areas and the growth patterns that can be extrapolated will allow reasonably confident prediction of the kinds of performance achievable in the future for the different classes of sensors and the kinds of new naval force applications that might be enabled.
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From page 117... ...
These virtues, and an enormous multidecade investment in time and resources, have led to the explosive proliferation of digital and microelectronics fabrication technologies that characterize and enable the rapid growth in computer and information technology. Linewidths continue to decrease exponentially with time, with optical lithography still performing effectively at submicron dimensions that were thought to be beyond its capability only a few years ago, and with finer, although less convenient, x-ray and electron-beam techniques waiting in the wings to continue the fabrication down into the regime of quantum dots and wires and ultimately to single electron logic structures about as far as can be imagined today.
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From page 118... ...
Si 1.124 I InP 1.344 D GaAs 1.424 D CdTe 1.475 D AlAs 2.153 I GaP 2.272 I ZnTe 2.394 D SiC 2.416 I GaN 3.503 D C 5.5 I densities continue to be reduced, the number of circuits that can be placed on a single chip with reasonable yield grows exponentially with time, causing the cost per operation to spiral downward while performance, in terms of clock speeds and throughput, continues its exponential upward growth a pattern of factor-of10 improvements every 4 or 5 years, which has been consistent for at least a decade and a half and shows no signs of slowing as yet. Figure 4.2 illustrates the exponential growth in the total number of transistors on a single chip from 1970 to the present and also extends the average observed growth pattern to the end of this study's time frame, 2035.
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From page 119... ...
cannot be used as an optical detector but rather that it requires a larger thickness than direct bandgap materials for the same detection effectiveness. Finally, the charge carrier mobility and saturation velocities are rather low for silicon compared with some of the other semiconductors, such as gallium arsenide (GaAs)
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From page 120... ...
technology based almost exclusively on GaAs. In addition to its electron mobility-related advantages, GaAs offers a direct bandgap, making it suitable for optical applications as a detector or as a light source, such as an LED or a laser, thereby easing the interface between its microwave and high-speed digital capabilities and the fiber-optical communication links that will be utilized for the transfer of data from some sensors to their associated computational resources.
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From page 121... ...
Next of interest in the III-V family for electronics and MMIC applications is InP. Although behind GaAs in development, InP exhibits even higher electron mobility characteristics than GaAs and also has a direct bandgap that is somewhat smaller than that of GaAs, but just right to permit bandgap engineering of LEDs and laser diodes in the two wavelength bands of most interest to long-distance fiber-optic communication applications (i.e., 1.3 ,um for minimum dispersion and 1.55 ,um for minimum loss)
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From page 122... ...
1995. ``The Potential of Diamond and sic Electronic Devices for Microwave and Millimeter wave Power Applications,,, Proceedings of the IEEE, 79(5)
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From page 123... ...
Of course, the real art at that time may come from technologies not envisioned today the details are rarely predictable, but it is highly probable that the envelope will persist. Higher Levels of Integration Digital Circuits Semiconductor transistors, particularly those designed for high frequencies, are by nature quite small the active dimensions of single transistors, whatever their design, are limited by fundamental physical properties of the materials, e.g.,
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From page 124... ...
The first key was to understand how to interconnect the active devices with useful passive components, equally small, that could be fabricated by the same photolithographic, deposition, diffusion, and etching techniques that produced the transistors. The second was to control the fabrication imperfections so that economical production yields of fully functional integrated circuits could be obtained.
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From page 125... ...
Although microwave transistors, optical detectors and emitters, and various passive components, including solidstate strip line and waveguide transmission line structures with low loss and good impedance control, can be made by the same microelectronics manufacturing techniques as used for digital electronics, these high-frequency applications cannot approach the level of integration that characterizes digital devices. Not only do these high-frequency applications demand more precise control over dimensions, impedance, and losses, but also the passive components required are physically much larger than those used by the digital implementations.
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From page 126... ...
MMICs are integrated circuits containing multiple active devices as well as integral passive components such as diodes, resistors, capacitors, inductors, and low-loss controlled-impedance transmission lines, and they perform useful microwave functions such as low-noise amplification (LNA) , power amplification (PA)
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From page 127... ...
Optical Components Detectors Focal Plane Arrays Semiconductors form natural optical detectors, because incident photons whose energy exceeds the bandgap (hv > EBG) readily kick electrons from the valence band up into the conduction band, giving rise to measurable electrical responses.
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From page 128... ...
Applying these same FPA concepts to the semiconductor materials needed for optimal performance in the longer IR bands, such as InSb, PtSi, or HgCdTe, is possible but is far less straightforward. Generally, in these technologies, implementing the readout circuitry on the same substrate with the detector elements in a monolithic form is not practical, and so the detector array must be interfaced to an external silicon very large scale integrated (VLSI)
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From page 129... ...
Because of the growing fiber-optics communication business, commercial sources for 1.3-,um and the 1.55-,um lasers abound. In addition to long-distance fiber-optic digital-communications applications, there is increasing interest in the possibility of using optics to transfer analog microwave signals within phased-array radars to supply time-delay steering, as well as to distribute the high-data-rate, large volumes of digital data associated with modern digital receiver radar concepts.
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From page 130... ...
OEIC chips in GaAs, combining high-bandwidth optical detectors with both matched digital electronics and MMIC amplifiers suitable for extracting digital and microwave information transmitted simultaneously on a single optical carrier, have already been demonstrated in the laboratory. Interest in this technology for the implementation of photonic radars with exceptional properties is running high at the present moment, but formidable practical obstacles still remain, and no photonic-based radar has yet been fielded.
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From page 131... ...
MEMS technology is an imaginative, but logical, exploitation of microelectronics. Through the use of traditional silicon fabrication techniques, microelectronic circuits and miniature, movable mechanical components with dimensions measured in microns are combined on a single substrate to perform a wide range of sensing and actuation tasks (Figure 4.5~.
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From page 132... ...
Although MEMS technology is being actively developed for commercial applications, the defense community cannot rely on the commercial sector to address all of its development needs because MEMS devices are highly application specific. Superconductor Technology High-temperature Superconductors Superconductor technology has shown tremendous potential for application to both ultralow-loss, high-Q microwave devices9 and to very-high-speed, verylow-power digital circuits advances that could be incorporated into advanced sensors in the near future through the maturation of high-temperature superconductor (HTS)
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From page 133... ...
Contrary to the popular image, the low temperatures required, although sometimes stressing and awkward with the earlier systems, are much less problematic with HTS technology and the newer generations of cryocoolers than are the basic materials and large-scale fabrication issues that remain. High-performance Microwave Devices The best known characteristic of superconductivity the direct current (do)
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From page 134... ...
semiconductor logic, which utilized the same trick to achieve high-speed performance in exchange for the higher powers associated with never entering the current-off state. Today, digital circuits and analog-to-digital converters of the RSFQ logic family are under investigation in several laboratories.
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From page 135... ...
Microelectronics The fundamental characteristics of the growth of digital electronics are most robustly described in terms of integrated circuit fabrication and performance parameters, independent of the semiconductor material systems, the device designs, or the circuit architectures employed or expected to be employed at different time periods to achieve each level of performance. As discussed above, envelopes representing the best of expected technology performance at different times are more reliable as predictors than are attempts to describe what any individual technology option will achieve.
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From page 136... ...
Digital technology is best characterized by the minimum achievable fabrication linewidth, the maximum area of defect-free chip that can be economically produced, and the clock speed achievable. The historical growth of minimum manufacturable mask fabrication linewidth projected to 2035 is illustrated in Figure 4.6.
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From page 137... ...
There is no evidence to suggest that this trend will not continue. By 2005, the clock speeds of affordable (desktop)
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From page 138... ...
Well before this, superconducting RSFQ logic, with its 100- to 300-GHz potential, should become available in HTS technology. By 2035, the end of the time horizon of this study, currently envisioned RSFQ technology may approach fundamental limits and the technology of choice may have shifted to superconductor quantum dots or a family of devices yet to be invented.
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From page 139... ...
The challenge remaining is to come up with practical, working, manufacturable devices in time to keep up with the exponential growth of digital electronics projected for the time frame beyond 2020. It seems likely that the transition from microelectronics to nanoelectronics and its future high-speed devices will depend on single-charge tunneling effects and the single-electron transistor.
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From page 140... ...
1, 1 , , · 1 , , 1 form of differentiation. the resulting filter loop structure is used to move the quantization noise away from the spectral regime that contains the signal information in such a way that when the signal and related quantization noise are
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From page 141... ...
Some digital circuits already are limited in performance more by the packaging and signal interconnection characteristics than by the basic clock speeds of the individual chips. Performance and packaging are interdependent, and in recent years these interdependencies have grown so strong that it is becoming increasingly difficult to separate the devices from their packaging.
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From page 142... ...
However, there are serious efficiency penalties associated with modulating the electrical signal information onto and off the optical carrier that are not present in the direct electrical approaches. In the future, as clock speeds and information bandwidths continue to grow, free-space and fiber-guided optical interconnects will certainly become the preferred way to transfer the ever-growing number of high-speed signals from board to board or even chip to chip.
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From page 143... ...
computers is described in more detail in Chapter 2 of this report. Perhaps the most interesting possibilities lie not so much with the large, multicomponent computers certain to be needed for powerful sensors systems, such as SAR radars and sonars, digital adaptive beamforming phased arrays, multisensor surveillance networks exploiting data fusion, and so on, but rather with the potential for combining, or in the extreme, integrating, monolithically on the same substrate, sensors with an ADC, a digital processor, and a communication output port to make a complete sensor system on a chip.
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From page 144... ...
uses digital beamforming, for example. As it will soon be practical to digitize the return signals on each receive antenna element close to, or at the front end of, a radar, even at X-band and above, digital beamforming of large arrays with hundreds to thousands of elements can be expected in the next 5 to 10 years for a wide range of applications.
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From page 145... ...
Automatic Target Recognition As the volume of sensor-provided data increases and the operational time of advanced weapon systems decreases, automatic target recognition (ATR) becomes mandatory no human can provide the necessary decisions fast enough.
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From page 146... ...
The approach, which promises to significantly improve ATR performance under these circumstances, is to collect multidimensional signatures and combine the information. That is, instead of relying on a single sensor operating on a single spectral band, provide multiple sensors, co-located or separated, that can collect data on many different spectral bands and provide some form of data fusion to properly register the multiple sources of information and to resolve any apparent contradictions.
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From page 147... ...
Better means of identifying information contained in large sensor-generated databases are required, as are better search strategies to efficiently exploit this information. Data Compression The final algorithm challenge lies in the necessity to communicate between sensors and from sensors to the users.
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From page 148... ...
Similar issues arise in semiconductor systems that exploit superconductor bandgap phenomena, such as S QUID s and RSFQ logic devices, and as a result use voltages comparable to the bandgap, i.e., millivolts. From the system side, as individual digital devices grow smaller and cheaper and simultaneously more computationally capable, the systems grow more complex.
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From page 149... ...
INDIVIDUAL SENSORS Having discussed the state of the art and the observed growth patterns of the five technologies identified as generic to all sensors, the panel now describes the advanced sensors known or thought to be critical to future naval applications that these technologies enable. Each of the individual sensor classes summarized in Box 4.5 is discussed briefly below, with the implications of the general technology trends and projected growth factored into the context of each sensor class.
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From page 150... ...
Most of the common technology trends identified earlier are exhibited by radar technology and provide excellent guidance to the potential future capabilities and applications of this key sensor class. Phased Arrays For many decades, radars have been evolving toward distributed phasedarray configurations.
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The result of these two conditions is arrays with hundreds to thousands of array elements. Unless the cost of each element is relatively small, phased arrays may simply not be affordable for many applications.
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From page 152... ...
Or, if several RF signals of differing spectral bands are passed simultaneously through an amplifier, large unwanted harmonics may be generated through inherent nonlinearity of the amplifier. In other configurations, if different types of RF systems are combined in close physical proximity because of the propagation characteristics of electromagnetic waves, it becomes extremely difficult to ensure that power radiated from one system's aperture or transmit elements does not couple adversely into another's receive elements, and so on.
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From page 153... ...
Not only will the next-generation radars be solid-state phased arrays, but they will also be almost entirely digital, confining the analog microwave portions to the extreme front end interface of the antenna with the outside world. Received signals will be digitized at the element after minimal analog processing e.g., with an antialiasing filter, a low-noise MMIC amplifier, and perhaps a single stage of up or down conversion and transmitted in digital form over wideband fiber-optic links to convenient remote locations off the aperture for processing, e.g., digital beamforming, in-phase (I)
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From page 154... ...
The word "photonics" is fairly imprecise, often used simply to indicate the use of optical techniques i.e., lasers, optical communication links (free space or fiber optic) , mirrors and lenses, and various hybrid components that consolidate optical, electro-optic, and electronic elements into monolithic structures known as optoelectronic integrated circuits (OEICs)
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From page 155... ...
Although it may find some niche applications, the photonic radar, on the other hand, is unlikely to supply the general-purpose capability inherent in a digital approach. Multidimensional Signatures Collecting additional sensor information about a target from multiple points of view is an obvious technique to improve sensor recognition performance and is one of the important common technology trends identified earlier in this chap
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From page 156... ...
Certain missile seekers currently under development are exploiting the first concept looking in several widely spaced spectral bands, e.g., RF and millimeter wave, or RF and IR, to generate complementary information. The second interpretation is already in use in the Navy's cooperative engagement capability (CEC)
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From page 157... ...
The richness of radio emitters in conflict areas and the availability of highly capable processing electronics suggest that meeting the need for new radar capabilities involves exploration of the possibility that they can be provided by bistatic and/or multistatic radar configurations using noncooperative emissions from such emitters. It is possible that the exploitation and further development of this branch of radar technology can be used to provide new radar capabilities for the naval forces radar capabilities that do not require the expense of radar transmitters and that can function in an almost totally covert manner.
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From page 158... ...
A combination of thinned arrays and digital techniques, by providing adequate spatial resolution, could extend the practicality of these techniques to lower RF frequencies, where the penetration is even better than at millimeter-wave frequencies. Electro-optics The optical portion of the electromagnetic spectrum has been growing in importance for many decades.
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From page 159... ...
When computers first appeared in the 1960s, optical systemsthe mirrors and lenses took a great leap forward as the invention process that had characterized the development of good designs up to then was replaced by a computer-aided engineering discipline that routinely produced affordable, optimized designs. Later, as various semiconductor detector materials were developed to cover different portions of the optical spectral bands, microelectronic fabrication techniques were applied to create imaging detector focal plane arrays (FPAs)
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From page 160... ...
. 5000 x 5000 1 000 x 1 000 100 x 100 1970 1980 1990 2000 2010 2020 2030 Year ~ FIGURE 4.10 Visible focal plane array technology.
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From page 161... ...
Uncooled Focal Plane Arrays. Recently, a new class of IR FPAs has appeared, using simple thermal halometer concepts rather than matched bandgap, exotic semiconductor materials.
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From page 162... ...
gas laser technology, toward diode-pumped, solid-state lasers that operate in the 1- to Alum region, near IR spectral bands with good coherence properties, sometimes supported with fiberoptic optical power amplifiers. This has led to significant reductions in transmitter power and volume requirements, enhancing the feasibility and practicality of using LIDAR to detect missiles or other aerial vehicles.
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From page 163... ...
In spite of these limitations, however, there is a broad class of applications for which the imaging LIDAR is well suited and for which it offers breakthrough capabilities. Effective target recognition, aim point selection, and precision guidance in the end game are critical for the success of surgical-strike weapons.
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From page 164... ...
Electronic Scan Optical-phased Arrays Optical systems have traditionally relied on analog techniques such as lenses and mirrors to provide beam control. Radar initially adopted the same approach with the use of steerable reflector antennas, but in recent years has largely abandoned this approach in favor of electronically steered phased-array systems that offer the capability for rapid, random beam placement, orders of magnitude faster than can be obtained mechanically.
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From page 165... ...
Liquid crystal optical phased arrays, with thousands of pixels, already have been fabricated for two-dimensional steering of laser wavelengths from the visible out to 10 ,um. Single incident beams can be steered to random positions, can be repositioned with high-precision repeatability, and can be split into complex patterns of spots that can be simultaneously focused and steered to all parts of the field of view.
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From page 166... ...
To get many acoustic wavelengths across the aperture, the sonar array often must be longer than the ship or submarine, often requiring towed arrays for good beam resolution. Finally, sonar signals, both active and passive, are often contaminated by multiple reflections from the sea surface and bottom and can be masked by many sources of natural noise such as waves, moving surface ships, and sea animals, thus requiring substantial clutter rejection processing for effective signal extraction.
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From page 167... ...
Whether MEMS technology can be applied to provide very compact, inexpensive, sensitive acoustic sensors is yet to be determined, but it seems likely. Another direction in transducer development involves attempts to achieve the broad-bandwidth high-power transmit waveforms assumed by the biologically motivated algorithms, through novel structures such as the slotted cylinder and multilayer stacks of polymer-based transducers.
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From page 168... ...
Since exponential growth in computational power is the direction in which technology is progressing, the ability to operate in littoral environments will certainly improve with time. The multitude of sources of strong noise in the littoral environment can be used as sources of natural illumination in the acoustic spectrum.
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From page 169... ...
MEMS permits the sensing masses to be very small and to be fabricated as an integral part of a silicon chip, which can also contain monolithic sensing electronics along with self-test, calibration, and signal-conditioning functions. Air bag sensors, utilizing MEMS technology to measure linear acceleration, are already available commercially.
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From page 170... ...
Ultimately one can expect to see the A/D conversion function integrated onto the sensor chip, along with exponentially increasing digital signal-processing and computing capabilities, to produce a self-contained, miniature inertial navigation capability full navigation, not just sensing and, no doubt, aided by GPS information, when available. Chemical and Biological Sensors Although sensing chemical or biological substances remotely at a distance is possible through the LIDAR, most chemical and biological sensors rely on direct physical contact between the sensor interface and the unknown or sought-for substance.
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From page 171... ...
With limited prototyping and testing under way at the University of Minnesota, this project targets a 200-g, 0.5-W mass spectrometer, about the size of a penny and costing only $20. As digital technology continues to evolve, doubling in capabilities every 2 years, the signal and data processing eventually will migrate onto the chip to form a smart mass spectrometer-on-a-chip.
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From page 172... ...
In addition to MEMS, a second large class of fiber-optic-based biological and chemical sensorsl7 seems quite promising in its sensitivity and breath of applicability. The potential of fiber optics for all kinds of sensing, particularly remote sensing, was recognized in the 1960s, and the technology was applied to the measurement of the oxygen content of the blood as early as 1962.19 Typically, the material to be identified is brought into contact with the end or a portion of an optical fiber, light from a laser source is sent down the fiber, and through selective absorption or scattering of the incident light by the unknown material or through the generation of fluorescence, the unknown is identified by patternmatching techniques based on the returned optical signals.
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From page 173... ...
Other Sensors General Local Sensors Beyond the major sensor classes explicitly discussed above, there are numerous other sensors for measuring just about anything one can imagine, including temperature, humidity, position, stress, strain, speed of flow, shape, roughness, stiffness, compliance, viscosity, electrical resistivity, inductance, interatomic distances, and so on. In terms of future growth, all can be expected to benefit from the digital revolution and the significant microelectronic and digital technology trends that have been described.
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From page 174... ...
FUTURE IMPACT ON NAVAL OPERATIONS Expected Evolution of Sensor Technology Based on the technology trends and historical growth patterns described, the panel anticipates that future sensor technology will be characterized by the following:
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From page 175... ...
Development of monolithic smart sensors, combining sensing transduction, ADC, digital signal processing, communication input and output, and perhaps power conditioning on a single chip. This offers interesting possibilities for very small, very smart weapons such as affordable smart bullets.
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From page 176... ...
Know Everything Situational Awareness With unlimited computational power and affordable, micro- and nanoelectronic monolithic sensor implementations in hand, the battlefield environment can be thoroughly examined by distributions of smart sensors and metasensors from multiple points of view, in multiple spectral bands, with high spatial and temporal resolution, through natural and manmade obscurations to provide a continuous awareness of the current situation. Who and what are present?
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From page 177... ...
Caveats The panel sets forth the following caveats: · The transition from microelectronics to nanoelectronics or to superconductor RSFQ logic implies significant reductions in operating voltages along with the threat of increasing EMI vulnerability. · As the number of observing, communicating sensors on the battlefield increases, the threat of data overload also increases.
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From page 178... ...
For many technologies, superconductor RSFQ logic, for example, considerable 6.2 and 6.3 engineering developments as well as investments in manufacturing technologies are required to attain the desired economical performance levels.
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From page 179... ...
In another sensor application, it is known that the former Soviet Union has already deployed dual-band optical missile seekers with antijam performance superior to that of U.S. systems.
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From page 180... ...
With this in mind, desktop computers with clock speeds of 1 GHz are expected to be commercially available by about 2005, and military applications of 1-GHz computers might reach the field over the next 5 years from 2005 to 2010. RECOMMENDATION Naval operations are increasingly dependent on enhanced sensor data to provide situational awareness, target designation, weapon guidance, conditionbased maintenance, platform automation, personnel health and safety monitoring, and logistic management.
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