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DOMINO-TYPE MICROWAVE AND MILLIMETER-WAVE SYSTEMS
A new concept is described which facilitates assembling microwave components without connectors and flanges. The new approach which is particularly well suited for millimeter waves is based on a modified H-guide. It allows interconnecting circuits by simply placing them in a row close to each other like domino pieces. The basic concept, the modified H-guide, fields and waves at a junction and domi
ANALYSIS OF CYLINDRICAL WAVEGUIDES OF GENERAL CROSS-SECTION
This paper describes a novel method for the analysis of waveguides of general cross-section. In this approach the field inside the waveguide is expanded in terms of cylindrical wave functions. The field is then subjected to the pertinent boundary conditions via an integral formulation. This procedure leads to a homogeneous system of linear equations from which both the cut-off frequencies and the
NEW KU-BAND LOW NOISE CONVERTER DIRECTLY COUPLED WITH HELICAL ANTENNA
This paper describes the constitution, characteristics, and technically unique key points on the design of the newly developed Ku-band converter. The converter is composed of a FET low noise amplifier directly coupled with a helical antenna and a new finline mixer.
AN L BAND PHASED ARRAY ANTENNA FOR MARINE SATELLITE COMMUNICATIONS
Commercial marine satellite communications over the Inmarsat system has as a rule seen a predominance of dish antennas used in shipboard terminal applications. A notable exception has been a phased array built by Chalmers University of Technology (Ref.!). In any case the shipboard antenna must track satellites in the presence of severe ship dynamics. For dish and fixed array antennas this requirem
SATELLITE NAVIGATION AT L-BAND USING A PROTOTYPE C/A CODE NAVSTAR GPS RECEIVER
The NAVSTAR Standard Positioning Service (SPS), available to the user community at L-band (Ll at 1575.42 MHz and L2 at 1227.6 MHz), is intended to playa primary role in civil navigation providing position, velocity and timing information on a global basis 24 hours a day. A prototype singlechannel NAVSTAR CIA code receiver capable of fulfilling the requirements of a low-dynamic environment is descr
A 2 GHZ, 18 AND 29 GHZ POINTING MECHANISM FOR SATELLITES
This paper deals with a study of the requirements for an RF linkage for use in a space-borne antenna pointing mechanism. The design of the rotating joints used within the pointing mechanism and their electrical performance is given.
ELECTRONIC TRACKING SYSTEMS FOR SATELLITE GROUND STATIONS
A new tracking technique for reflector antenna configurations is described. Using simple waveguide components in the primary feed chain, mode conversion is employed to induce a beam squint in the secondary pattern of the antenna. The principle of operation is described and various salient features identified. A prototype antenna system incorporating electronic beam steering has been field evaluate
EFFECT OF COMBINED TUMOUR THERAPY INCLUDING HYPERTHERMIA ON DIELECTRIC PROPERTIES OF RAT TISSUE
microwave-heated Co-y-irradiated and R1H) and skin measured in vivo between 0.2 and 2.4 GHz. An open ended coaxial line and a computer controlled network analyzer were used to collect data. Co-y-radiation does not alter the dielectric properties. A combined t~eatment with Co-y-rays and microwave hyperthermia results in significant changes of the dielectric properties mainly in the skin due to an
COMPUTER SIMULATION FOR HYPERTHERMIA TREATMENT PLANNING
A numerical procedure to calculate and optimize transient temperature distributions in realistic cross sections of the human body is described. In the simulation, the therapeutic effect of the tumor temperature distribution is maximized by regulating superficial skin cooling and microwave power of multiple applicators while minimizing normal tissue damage. Results pertaining to the treatment of a
NON-INVASIVE PHASED ARRAY TECHNIQUE FOR ACHIEVING DEEP HYPERTHERMIA
Results are presented which demonstrate both localised heating at depth in a homogeneous phantom and the problems caused by the more realistic case of a layered tissue equivalent phantom. A technique for overcoming the problems due to the layers by using an array of contacting radiators is proposed. A computer model based on 'plane to plane' spectral diffraction combined with the cascade transmiss