This paper presents a unique design concept for a dual-frequency,electronically steerable, MM-wave phased array antenna using Monolithic Microwave Integrated Circuit (MMIC) technology. Such an antenna design will be found most attractive for satellite communication and missile seeker applications, where size, weight and power consumption are the most stringent requirements. The block diagram of a dual-frequency (20 GHz/30 GHz), electronically steerable, phased array antenna using MMIC technology is shown in Figure 1. Specific details on the critical RF components are also shown in Figure 1. Because of the location of the radiating elements on the hemispherical surface, the antenna is inherently capable of providing electronic scanning over 360 deg. in AZ-plane and over plus/minus 60 deg. in EL-plane. This electronically steerable phased array antenna will generate multiple beams in the AZ-plane with consistent bandwidth and pattern symmetry. This design exploits true integration of printed circuit antenna technology, GaAs active device technology, MM-wave microstrip technology and printed circuit time delay phase shifting element technology. This design employs microstrip periodic structure transmission line sections as time delay phasing elements, which requires no input power. The printed circuit microstrip line sections will be used as feed networks. Two distinct dual- frequency, antenna element fabrication techniques, namely, stacked-patch element (Figure 2a) and collocated, interleaved-patch element (Figure 2b), were investigated in terms of cost, size, performance and complexity. Tradeoff studies performed seem to indicate that stacked-patch element approach will offer minimum size and weight. The physical dimensions shown in Figure 1 and 2 are computed for 20 GHz and 30 GHz operations. All the electronics, control circuits and RF MMIC circuits can be located within the hemispherical structure. The input power, overall system size and weight will depend on the antenna gain requirement, inter-element spacing, number of elements and phase shifter types. It is important to mention that delay line phasing networks using printed circuit periodic structures will provide optimum flexibility in phasing of the antenna elements with minimum loss. The proposed antenna architecture for a dual-frequency operation using a common aperture and MMIC technology seems to offer an antenna system with minimum cost, size, weight and power consumption.
This paper reveals narrowband tunable optical filter configuration employing acousto- optic technology. The filter provides tuning capability over the entire blue-green spectral region within one second. The design configuration offers maximum economy, remarkable versatility, uniform spectral response and constant narrow bandwidth less than 0.2 nm. The proposed filter architecture uses state-of-the art technology components to meet narrowband requirements.
The main object of this paper is to identify solar panel installation configurations to achieve optimum system performance irrespective of installation surface configurations. It is important to mention that the panel installation requirements are strictly dependent on the roof configurations, Northern and Southern hemispherical locations, and the latitudes of the installation locations. Panel installation schemes for flat roof, inclined roof, inverted V-shape roof and other roof configurations are briefly discussed. Potential tracking concepts, tracking algorithms, and controllers are identified.
This paper present an unique IR sensor technology capable of providing effective
deception and noise jamming IReM capability to ward off threats posed by SFMs or
STINGER missiles operated by various terrorist groups and Islamic radicals. More than
60,000 such missiles are currently in the hands of Islamic radicals and terrorist groups.
Even one such missile can bring down a commercial jet transport carrying more than 350
passengers. The proposed IReM system deploys innovative jamming technique to
confuse the missile seeker receiver by introducing sharp FM-modulated noise spikes in
the receiver bandwidth, thereby preventing the detection and tracking of aircraft.
This paper reveals performance capabilities of state-of-the-art electro-optic and photonic devices, which are best suited for security and defense system applications. These devices can be used in battlefield, space surveillance, medical diagnosis, and detection of terrorist activities. Performance capabilities of fiber optic components for possible applications in WDM and DWDM systems are summarized. Photonic devices for covert military and security communication applications are identified with particular emphasis on performance and reliability. Performance parameters of Erbium-doped fiber amplifiers (EDFAs), Erbium-doped waveguide amplifiers (EDWAs), and optical hybrid amplifiers (OHAs) comprising of EDFAs and Raman amplifiers are discussed with emphasis on bandwidth, gain-flatness, data handling capability, channel capacity and cost-effectiveness. Performance parameters of very long wavelength infrared (VLWIR) detectors are summarized, which have potential applications in remote sensing and ballistic missile defense applications. Electro-optic and photonic devices best suited for security and defense applications are identified.
Microelectromechanical System (MEMS) switches offer outstanding performance over wide bandwidth, minimum weight, sue, and power consumption, and significantly improved reliability unmatched by
any other electronic switches deploying GaAS FETs or GaAs PIN-diodes or GaAs HEMTs. These switches are best suited for applications that require high signal purity in terms of signal linearity, insertion loss, isolation, and power consumption. RF-MEMS switches offer reliability exceeding ten billion life cycles and low insertion
loss and high isolation while operating over uh-wideband. Design parameters and fabrication aspects of RF-MEMS shunt and series switches are investigated, which will permit switch operation over 60 to 94 GHz range.
This paper reveals performance capabilities of critical fiber optic components and photonic devices, which have potential applications in industrial, commercial and military systems and equipment. These devices are widely used in battlefield, space surveillance, medical diagnosis, crime fighting, and detection of terrorist activities. Performance capabilities of fiber optic components for possible applications in WDM and DWDM systems are summarized. Photonic devices and sensor for forward battlefield applications are identified with emphasis on performance and reliability. Performance parameters of Erbium-doped fiber amplifiers, Erbium doped waveguide amplifiers, and optical hybrid amplifiers comprising of EDFAs and Raman amplifiers are discussed withe emphasis on bandwidth, gain-flatness, data handling capability, channel capacity and cost-effectiveness.
Diode-pumped solid state (DPSS) lasers employing diode arrays and optical crystals suffer from excessive weight, low conversion efficiency, and high fabrication cost. This paper reveals a unique design of coherent, high performance InGaAsP/InP strained-layer quantum-well (QW) semiconductor laser capable of delivering CW power output greater than 500 mw at 1.55 microns. It is important to mention that InGaAsP/InP strained-layer double-quantum-well (DQW) laser diodes are capable of yielding even higher optical power output with improved differential quantum efficiency (DQE) and with lower threshold current at 20 deg C. Compact packaging, minimum power consumption, eye-safe operation and minimum cost are the major benefits of this laser design.
This paper reveals unique performance capabilities of High-TemperatureSuperconducting Thin-Film(HTSCTFs) for possible applications in microwave bandpassfilters(BPFs). Microwave filters fabricated with HTSCTFs have demonstrated lowestinsertion loss, highest rejection, and sharpest skirt selectivity. Thin films of YttriumBarium Copper Oxide(YBCO), Bismuth Strontium Calcium Copper Oxide(BSCCO) andThallium Calcium Barium Copper Oxide(TCBCO) will be most attractive for filters.
This paper reveals potential applications of microstrip meander line slow-wave structures in MM-Wave MMIC circuits. Transmission and reflection coefficients are computed employing dyadic Green functions and Sommerfield integral. Computer analysis has assumed lossless substrate and microstrip transmission lines with strip thickness much less than wavelength. Resistive and surface wave losses are included in the mathematical treatment. Frequency dependent, surface impedance boundaries are evaluated using a quasi-TEM mode computer analysis. This provides on overall effect of the penetration by the electric field and the resultant current distribution within the microstrip lines. Potential applications of these structures include phase shifters, filters, and delay lines.
This paper reveals potential applications of high-temperature superconductors in microwave and millimeter-wave circuits. Implementation of superconductivity technology will significantly improve the performance of microstrip lines, chirp filters, delay lines, amplifiers, oscillators, and switching networks. Superconductivity offers compact packaging, ultra-high switching speeds, minumum loss, lowest power dissipation, and minumum signal distortion.