How to Design an Embedded RDBMS Search

As the cost of micro-disk and NAND Flash continue to drop, devices are storing more and more data. It is common now for a person's MP3 player to have more storage than their laptop. But this increase in storage capacity has not been matched with advances in the user interface. Typically, users still wrestle with a folder-based interface to find the data they want, searching by a few vendor-defined categories such as artist, album, and genre. But a new class of embedded database manage- ment systems (DBMS) is emerging to allow end users to search the way people think, rather than in this stat- ic manner. With a RAM footprint ranging from a few tens to a few hundred kilobytes, these products enable developers to deliver this sophisti- cated search on mobile devices. So how do they work? How do you write an embedded application to use a relational DBMS (RDBMS)? While there are a few kinds of DBMS, the relational model has tri- umphed over all the others, largely because it abstracts the data struc- tures so that applications don't have to know them. A relational database management system offers a standard, high-level query language that allows access to data by content, not by pointer or location and offset.

Posted in: Application Briefs, Application Briefs, Board-Level Electronics, Electronics & Computers, Architecture, Human machine interface (HMI), Data management

WIN-T: The Warfighter's Communications Backbone for Today and Tomorrow

The battlefield of the future will integrate all elements into one networked force, enabling communication among soldiers and commanders on the land, at sea, in the air, and at fixed command posts. Developed by a team led by General Dynamics C4 Systems and Lockheed Martin, the Warfighter Information Network - Tactical (WIN-T) project is the tactical communications backbone for the warfighter, both today and for the future. WIN-T supports voice, video, and data applications, enabling the soldier to stay connected anytime and anywhere by providing mobility and reliable bandwidth. Leveraging communications technologies such as cellular, wireless LAN, satellite, and VoiceOver IP, WIN-T links weapons, intelligence, surveillance, and reconnaissance, while remaining mobile, scalable, modular, and secure.

Posted in: Articles, Aerospace, Satellite communications, Telecommunications systems, Military vehicles and equipment

Open-Standard Multicomputers Address Next-Generation Multi-Function Radar Applications

Next-generation radar applications will drive performance demands that will have architectural implications for radar computing and electronics. Advanced multi-function radar (MFR) systems, which will be deployed in harsh and demanding environmental conditions inside unmanned aerial vehicles (UAVs), manned aircraft, and ship- and ground-based radar systems must simultaneously provide multi-mode search, multi-target tracking, synthetic aperture radar (SAR) imaging, and space time adaptive processing (STAP). Both the performance and ruggedization requirements make it challenging to service MFR applications using yesterday's commercial- off-the-shelf (COTS) technologies.

Posted in: Articles, Aerospace, Architecture, Radar, Systems engineering, Durability, Reliability

Front-End Mixed-Signal Receiver on a Chip

A mixed-signal receiver on a chip (RoC) now undergoing development is intended to be a prototype of the front ends of lightweight, compact, low-power, relatively inexpensive heterodyne radio receivers for future phased array radar systems. [As used here, "mixed-signal" refers to a design for utilization of both analog and digital signals, and "front end" signifies the portion of a heterodyne receiver that processes the raw radio-frequency (RF) input to produce an output at an intermediate frequency (IF) that is the difference between the RF and the frequency of a local oscillator (LO).] The RoC will include two integrated circuits, denoted IC1 and IC2 respectively, that comprise integrated chipsets designed and fabricated on the basis of the International Business Machines 7HP generation of SiGe bipolar complementary oxide/semiconductor (BiCMOS) technology.

Posted in: Briefs, Electronics & Computers, Radar, Radio equipment

A Predictive Model for Cognitive Radio

A computational model that predicts effects of changing operational parameters of a cognitive radio has been developed as part of continuing research on cognitive / software - defined radio (C/SDR) data-communication networks. The term "cognitive radio," "software-defined radio," or "smart radio" denotes a radio transmitter, receiver, or transceiver, (1) much of the functionality of which is implemented in software and (2) that is able to reason about its configuration on the basis of requirements and its environment.

Posted in: Briefs, Software, Radio equipment

Metamaterials for Advanced Microwave Antennas

A report discusses a research and development project that has made contributions to the art of metamaterials for directing electromagnetic radiation at frequencies of the order of several gigahertz. The next-generation metamaterials expected to emerge from this and related projects could enormously improve the performances of microwave radar and communication antennas.

Posted in: Briefs, Materials, Antennas

Heterodyne RF/Optical Links Utilizing Integrated Photonics

A program of research and development has been directed toward the goals of demonstrating (1) ultra-low-noise communication links in which information is conveyed by phase-modulated radio-frequency (RF) carrier signals that are, in turn, used to modulate laser-generated optical carrier signals and (2) implementation of transmitters and receivers in such links by means of several key integrated optoelectronic and photonic components. Notably, the scheme for integrating these components is based on the use of asymmetric twin optical waveguides (see figure) that afford design versatility in that they enable the use of a broad range of components useful in RF/photonic applications.

Posted in: Briefs, Photonics, Optics, Waveguides, Research and development

Microwave Sources Utilizing Linear Induction Accelerators

Progress has been reported in a continuing effort to develop pulsed, high-power microwave signal sources based on (1) oscillators in the form of relativistic magnetrons containing transparent cathodes, and (2) hybrid antenna/ amplifiers powered via electronbeam generators. The underlying concept is that a compact, high-power microwave source could be constructed by integrating an electron-beam accelerator with a radiating antenna and an electrodynamic-interaction space.

Posted in: Briefs, Electronics & Computers, Amplifiers, Antennas

Accomplishments of the Microwave Power Research Initiative

Research performed under the auspices of the Microwave Power Research Initiative (MiPRI) between May 1, 2005 and April 30, 2006 has been reported. [The MiPRI is a congressionally mandated Air Force program to advance the science of high-power electron- beam-driven microwave and millimeter- wave signal sources.] The reported research was performed by a consortium of three universities led by the University of New Mexico and including the University of Michigan and the Massachusetts Institute of Technology (MIT). The research pertains to two signal sources of current interest to the Air Force: a relativistic Lband magnetron and a W-band source.

Posted in: Briefs, Electronics & Computers, Telecommunications, Research and development, Technical reference, Radiation

Microstrip Patch Antennas Containing Multi-PBG Structures

Microstrip patch antennas of a proposed type would contain photonic- bandgap (PBG) structures characterized by multiple bandgaps. In a given antenna, the PBG structure(s) could be one or more periodic dielectric and/or metal structures that could be embedded in the dielectric substrate of the antenna and/or formed on either or both faces of the dielectric substrate. As explained below, the incorporation of PBG structures would facilitate the design of a smaller antenna capable of providing a given amount of gain at a given frequency.

Posted in: Briefs, Electronics & Computers, Antennas, Architecture, Insulation