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INCREMENTAL PROPAGATION PROCEDURE FOR CALCULATING SCATTERED FIELDS FROM ARBITRARY CONDUCTORS
A computationally efficient method is described for calculating the scattered fields from conducting bodies of arbitrary shape. The process is non-iterative and incrementally propagates a planar field distribution through the conductor via spectral decomposition of the wave, inserting the necessary boundary conditions as required. Integration is performed numerically using Fast Fourier Transform r
SPECTRAL DOMAIN APPROACH FOR RADIATION MODES IN A DIELECTRIC SLOT LINE
The spectral domain approach for hybrid radiation modes (called E-HS) of a dielectric slot line is presented. It is shown that the spectral domain of E-HS modes consists of two parts describing the far-zone and the near-zone field behavior respectively. The orthogonality of radiation modes in the far-zone field is demonstrated. The construction of a E-HS mode from a combination of four partial dif
COMPUTATION OF THE DISSIPATED POWER IN CLOSED MICROWAVE SYSTEMS BY THREE-DIMENSIONAL FINITE DIFFERENCES
The three-dimensional dielectric interface are presented. The finite difference scheme is used to solve Maxwell's equations in closed microwave systems. A boundary condition at an abrupt and a modal absorbing boundary condi tion for waveguides calculation of the sinusoidal steady-state amplitude and phase of the electromagnetic (EM) field, and the derivation of the power-density are discusse
FREQUENCY MULTIPLYING POWER-COMBINING SLOT ARRAY
A quasi-optical frequency multiplying slot array for high power millimeter wave applications has been demonstrated. Single slot conversion loss measured for X, Ka and E-band models produced encouraging results. An 8-element multiplying array exhibited better than -12 dB sidelobe level at 70 GHz. The simple planar structure makes mm IC fabrication feasible.
STABLE MILLIMETER WAVE SOURCES USING SUBHARMONICALLY INJECTION LOCKED GUNN-OSCILLATORS
94 GHz stable sources using 2nd harmonic GaAs Gunn diodes and injection locking at 47 GHz by a high order avalanche frequency multiplier have been built. These sources exhibit a very low FM noise (less than 80 dBc/Hz, 10KHz from the carrier frequency). Power combining with InP fundamental Gunn diodes has provided medium power (30 - 50 mW) highly stable sources which enable frequency tuning and fre
HIGH POWER HIGH EFFICIENCY MILLIMETER WAVE TED'S WITH REVERSE-BIASED HETERO-JUNCTION CATHODE CONTACT
The purpose of this paper is to present theoretical results on current limiting cathode contact InP TED's in the millimeter wave range. The current limiting effect is obtained from a reverse-biased GaInAsP on InP isotype heterojunction. This kind of cathode contact yields an efficient over length dipolar layers mode up to the ultimate cut-off frequency of the negative differential mobility in
HIGH POWER, HIGH EFFICIENCY LP. MOCVD InP GUNN DIODES FOR 94GHz
High power and high efficiency InP Gunn diodes which were made from layers grown by LP-MOCVD have been developed in the millimeter-wave range. The Gunn diodes, processed using the integral heat sink technique have delivered up to 100 mw cw output power with 2,5 % efficiency at 94GHz, while average power levels in excess of 90 mw were obtained at 94GHz. The Gunn diodes operated at a bulk temperatur
A FUNDAMENTAL-MODE InP GUNN DIELECTRIC RESONATOR OSCILLATOR AT 94 GHz
A FUNDAMENTAL-MODE InP GUNN DIELECTRIC RESONATOR OSCILLATOR AT 94 GHi N. MAMODALY*, F. FARZANEH**, A. BERT*, J. OBREGON**, P. GUILLON** ABSTRACT This paper presents a new way to implement a stable low noise source at 94 GHz. It involves for the first time a dielectric resonator coupled to an InP Gunn diode, oscillating in the fundamental mode. A 15 dB noise reduction is obtained as a result of
MILLIMETER WAVE GaAs IMPATT DIODES
MILLIMETER WAVE GaAs IMPA'IT DIODES D. Masse, M. G. 1\dlerstein, ABSTRACI' L. H. Holway, Jr. * Amplifiers and oscillators, using gallium arsenide (GaAs) double-drift IMPATT diodes have beacome one of the leading solid-state contenders to replace electron tubes as power sources in millimeter wave systems. In this paper, we describe the state-of-the-art performance obtained in our laboratory thr
NEAR-CLUTTER-SUPPRESSION IN CW-RADAR-SYSTEMS BY DETERMINISTIC FSK-MODULATION
NEAR-CLUTTER-SUPPRESSION IN CW-RADAR-SYSTEMS BY DETERMINISTIC Wolfgang FSK-MODULATION Wigger Knapp and Burkard ABSTRACT PNPSK modulated CW-Radar-Systems may be affected by short range reflections Due to the very high interference-power-level caused by unwanted reflections nonlinearities or other hazardous effects occur in the receiver front-end and the signal processing circuitry. Under such