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Diode lasers for mass market applications: optical recording and printing
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| Pengarang | : | D.B. Carlin |
| Nama Majalah/Jurnal | : | Proceedings of the IEEE |
| Volume / Edisi | : | 82-4, APRIL (No. 4) |
| Halaman | : | 469-481 |
| Abstrak | : | The existence of inexpensive semiconductor diode lasers has led to realization of consumer products in the home entertainment and personal computer industries that are already successful and promise to continue to grow in value. For example, optical recording has proven to be a technology that not only has become a dominant factor in the audio market (CD player), but has found markets as memory peripherals for personal computers and the playback of prerecorded video. In addition, diode laser printers for personal computers will become a large market. Diode-laser-based optical recording and printing systems are reviewed in this paper, as are the properties of the diode lasers that allow these systems to operate so well. Future developments in diode laser technology that will allow enhanced or new systems are also described. |
Consumer electronics: an important driver of integrated circuit technology
| Pengarang | : | E.A. Sack |
| Nama Majalah/Jurnal | : | Proceedings of the IEEE |
| Volume / Edisi | : | 82-4, APRIL (No. 4) |
| Halaman | : | 465-468 |
| Abstrak | : | Consumer electronics has played an important role in the development of integrated circuit technology. Inversely, the integrated circuit has made possible low-cost but highly complex products that we have come to depend upon for enjoyment and convenience in our lives as family units or individual consumers. Integrated circuit production economics favor volume applications and the "one per human being" opportunity presented by consumer products can be a powerful driver. The performance requirements for consumer applications, including low cost, low power, battery operation, nonvolatile memory, high-frequency amplification and scanning, lightweight and pleasing as well as convenient input/output means have led to many innovations in the evolution of the integrated circuit. |
At the crossroads of the information highway: new technology directions in consumer electronics
| Pengarang | : | - |
| Nama Majalah/Jurnal | : | Proceedings of the IEEE |
| Volume / Edisi | : | 82-4, APRIL (No. 4) |
| Halaman | : | 459-464 |
| Abstrak | : | The advent of consumer electronics dates back to the invention of the vacuum tube and its application to one of the first consumer electronics products-the radio. Since that time technology development and subsequent applications have expanded the scope of "consumer electronics." Today, technology advances on many fronts including compression, digital signal processing, computing power, displays, communication, and software are cascading to cause a virtual explosion of new consumer electronics products, applications, and services. This paper describes "consumer electronics" within the context of the IEEE Consumer Electronics Society and explores future directions |
Applications of fuzzy sets and approximate reasoning
| Pengarang | : | - |
| Nama Majalah/Jurnal | : | Proceedings of the IEEE |
| Volume / Edisi | : | 82-4, APRIL (No. 4) |
| Halaman | : | 482-498 |
| Abstrak | : | This paper discusses recent applications of fuzzy sets and the theory of approximate reasoning. The primary focus is on fuzzy logic control (FLC). We begin with a brief history of the key ideas, a survey of recent applications, and a discussion of the genesis of FLC in Japan. We then turn to a study of the general principles of FLC, considering it as a combination of ideas from conventional control theory, artificial intelligence, and fuzzy sets theory. We next provide a detailed analysis of a simple application in consumer electronics, namely, a fuzzy washing machine developed by Hitachi Corporation. In concluding sections we briefly consider other types of applications, including recent work on pilotless helicopters, fuzzy expert systems, and the concept of a fuzzy computer, and we discuss the potential for future developments. It is our opinion that the subject of FLC is still very much in its infancy, and that recent events mark the beginning of an entirely new genre of "intelligent" control. |
Evolution of flat-panel displays
| Pengarang | : | - |
| Nama Majalah/Jurnal | : | Proceedings of the IEEE |
| Volume / Edisi | : | 82-4, APRIL (No. 4) |
| Halaman | : | 499-509 |
| Abstrak | : | The evolution in performance and manufacturability of liquid-crystal displays has created a new reality in the electronic information displays industry. LCD's now outnumber all other flat-panel displays in production volume, by more than two orders of magnitude. LCD's may equal CRT's in market sales by the year 2000. However, LCD's are still an order of magnitude more expensive than comparable performing CRT's. LCD's are enabling new products, such as personal digital assistants, moving map navigators, picture telephones, etc., which could not he readily done with CRTs because of their size and sensitivity to ambient illuminations. The LCD technology in various modes, from passive twisted nematic to active matrix, is being used in all product sizes, from the 0.7-in camcorder viewfinder to the 14-in full-color display with XGA resolution. Full color is very important in future products and any flat-panel display technology without it will be relegated to niche markets. |
Digital television
| Pengarang | : | - |
| Nama Majalah/Jurnal | : | Proceedings of the IEEE |
| Volume / Edisi | : | 82-4, APRIL (No. 4) |
| Halaman | : | 510-519 |
| Abstrak | : | It is now recognized worldwide that all television services, including HDTV, will eventually become digital, but there is wide disagreement about the optimum timing for transforming existing analog systems. A major driving force is the ongoing partial merging of television and digital computers in interactive multimedia services involving digital television and applications in areas like information (news), education, medical, entertainment, etc. A major target is to maximize interoperability of video services at all levels, including various resolutions, different transmission and storage mechanisms, as well as bit rates. This paper provides an overview of the current status in digital television, techniques used, future prospects, and research areas that need to be investigated. The maturity of compression techniques needed for digital video storage and transmission, and the establishment of international standards for digital television representation, like MPEG-2, have greatly contributed in this transformation. Recent developments are mentioned, including the American "Grand Alliance" FCC effort for digital terrestrial HDTV broadcasting, and also other efforts for digital television by cable and DBS. The concept of hierarchical multiresolution coding is also explained, and some of its techniques are briefly described. |
A new generation of SIS receivers for millimeter-wave radio astronomy
| Pengarang | : | J.M. Payne |
| Nama Majalah/Jurnal | : | Proceedings of the IEEE |
| Volume / Edisi | : | 82-5, MAY (No. 5) |
| Halaman | : | 811-823 |
| Abstrak | : | A new generation of low-noise, dual-polarization heterodyne receivers covering all atmospheric windows between 68 and 300 GHz has been developed for the 12-m telescope on Kitt Peak, AZ, operated by the National Radio Astronomy Observatory (NRAO). A modular approach to the receiver construction has been used. Each receiver channel is constructed as a self-contained insert which is mounted in a dewar equipped with a closed-cycle 4 K refrigerator capable of cooling up to eight inserts, thereby enabling several frequency bands to be contained within one dewar. The telescope and receiver optics are so arranged that switching between frequency bands may be accomplished rapidly by rotating the optical elements placed in the signal path. Single-sideband noise temperatures ranging from 50 to 400 K are obtained across the frequency range. |
Ruby masers for maximum G/T/sub op
| Pengarang | : | - |
| Nama Majalah/Jurnal | : | Proceedings of the IEEE |
| Volume / Edisi | : | 82-5, MAY (No. 5) |
| Halaman | : | 796-810 |
| Abstrak | : | The Deep-Space Network (DSN) includes world-wide networks of 26-, 34- and 70-m antennas in Australia, Spain, and the USA. Ruby masers are used on the 34and 70-m antennas to maximize the system operating noise temperature and thereby maximize the DSN receiving system figure of merit, antenna gain divided by system operating noise temperature. These systems are used for deep-space telecommunications, solar system radar, and radio astronomy. Cavity, traveling-wave, and reflected-wave maser designs and performance characteristics from 960 MHz to 34 GHz are summarized. Effective noise temperatures of ruby masers are addressed with emphasis on a 33.68-GHz maser where quantum noise is a major source of noise. |
The fractional frequency stability of a 34-m-diameter beam-waveguide antenna
| Pengarang | : | - |
| Nama Majalah/Jurnal | : | Proceedings of the IEEE |
| Volume / Edisi | : | 82-5, MAY (No. 5) |
| Halaman | : | 788-795 |
| Abstrak | : | Advances in fiber-optic technology have made it possible to develop a new technique to isolate and measure the frequency stability of a large beam-waveguide (BWG) antenna. Through the use of the technique described in the paper, at both 46.5/spl deg/ and 37/spl deg/ elevation angles, under good weather conditions, the degradation of the the fractional frequency stability of signals passing through the antenna path was measured to be between 1.3 and 2.2/spl times/10/sup -15/ for sampling intervals of 1024 s. These stability values apply to the portion of the antenna that includes the main reflector, subreflector, tripod legs, and six BWG mirrors. These test results are believed to be the first successful fractional frequency stability measurements made on the microwave optics portion of a large antenna to a level of 1 or 2 parts in 10/sup 15/. |
Precision DSN radiometer systems: impact on microwave calibrations
| Pengarang | : | C.T. Stelzried |
| Nama Majalah/Jurnal | : | Proceedings of the IEEE |
| Volume / Edisi | : | 82-5, MAY (No. 5) |
| Halaman | : | 776-787 |
| Abstrak | : | The NASA Deep Space Network (DSN) has a long history of providing large parabolic dish antennas with precision surfaces, low-loss feeds, and ultra-low noise amplifiers for deep-space telecommunications. To realize the benefits of high sensitivity, it is important that receiving systems are accurately calibrated and monitored to maintain peak performance. A method is described to measure system performance and to calibrate the receiving system using procedures, software, and commercial instruments that are easy to implement and efficient to use. The utility of the measurement procedures and the precision of the receiver calibration technique were demonstrated by performing tests at Ka-band (32 and 33.68 GHz) frequencies at Goldstone on a 34-m beam-waveguide antenna. Observations of multiple calibration radio sources are used to measure the dependence of antenna gain and system noise temperature on source elevation and derive the performance parameters. The experimental results described illustrate some of the ways that receiving system nonlinearity can negatively impact system performance. A simple radiometer calibration technique and analysis provide quantitative information that enables the system engineer to adjust and linearize the receiving system. When that is not practical, the experimenter or the operator can apply connection coefficients to the measured values of system noise temperature and thereby compensate for the receiving system nonlinearity. |