Abstract: Heating pattern uniformity is provided in a coaxial microwave hyperthermia probe by varying the open area in the outer conductor in an axial direction such that there is a maximum open area in the axial center portion. The variations may be provided by winding an outer conductor in a helical pattern with a variable pitch or by cutting openings of axially varying size in a solid outer conductor. The invention is applicable to both flexible and rigid probes.

Abstract: Heating pattern uniformity is provided in a coaxial microwave hyperthermia probe by varying the open area in the outer conductor in an axial direction such that there is a maximum open area in the axial center portion. The variations may be provided by winding an outer conductor in a helical pattern with a variable pitch or by cutting openings of axially varying size in a solid outer conductor. The invention is applicable to both flexible and rigid probes.

Abstract: An isolator for insertion in a coaxial cable between an RF generator and a device employing RF energy provides isolation against DC and low frequency (60 Hz) AC while passing the RF energy with low attenuation and a low reflection ratio. The isolator has a longitudinally extending central conductor spacedly surrounded by an inner conductor. The central conductor and inner conductor are connectable to the ends of the center conductor of the coaxial RF cable. A first outer conductor of the isolator spacedly surrounds the inner conductor and a second outer conductor spacedly surrounds the first outer conductor. Insulators are provided between the central and inner conductors, between the inner conductor and the first outer conductor and between the two outer conductors. The outer conductors of the isolator are connectable to the sheath of the coaxial RF cable.

Abstract: Heating pattern uniformity is provided in a coaxial microwave hyperthermia probe by varying the open area in the outer conductor in an axial direction such that there is a maximum open area in the axial center portion. The variations may be provided by winding an outer conductor in a helical pattern with a variable pitch or by cutting openings of axially varying size in a solid outer conductor. The invention is applicable to both flexible and rigid probes.

Abstract: In rotating anode X-ray tubes it has not been the practice to provide anode cooling because of problems in arranging coolant flow. A further problem which has arisen, particularly in tubes for computerized tomography which should have precisely defined focal spots, is off-focus radiation apparently resulting from back scattered electrons hitting the tube target away from the focal spot. It is here proposed to provide a rotating anode X-ray tube with a shroud surrounding and close to at least part of the anode. This is extended towards the electron gun with an aperture through which the electron beam travels and an X-ray emissive window. The shroud collects back scattered electrons and can also be fluid cooled. The window provides some collimation and the edges can be shaped to restrict the focal spot as viewed away from the main X-ray beam.

Abstract: In a computer-assisted tomography (CAT) apparatus, in which a fan-shaped X-ray distribution is rotated about the patients body, it is possible to use a ring of stationary detectors disposed to receive the radiation after passage through the body. In this arrangement the ring of detectors is of smaller radius than the locus of motion of the radiation source. It would appear that this would cause the detectors to obscure the body from the radiation. An arrangement disclosed moves out of the radiation beam those detectors which would present an obstruction so that only those required to collect radiation lie in the beam.

Abstract: In a computer-assisted tomography (CAT) apparatus, in which a fan-shaped X-ray distribution is rotated about the patients body, it is possible to use a ring of stationary detectors disposed to receive the radiation after passage through the body. In this arrangement the ring of detectors is of smaller radius than the locus of motion of the radiation source. It would appear that this would cause the detectors to obscure the body from the radiation. An arrangement disclosed moves out of the radiation beam those detectors which would present an obstruction so that only those required to collect radiation lie in the beam.

Abstract: A technique for processing the IF portion of a radar return signal in order o provide the remote detection and measurement of atmospheric turbulence occurring within precipitation. The technique employs an amplitude limiter, a wideband discriminator and a video amplifier to provide real time measurement of the precipitation velocity. A velocity comparison at various radar ranges is made to provide an indication of the turbulence. The analog circuit employed to make this measurement operates with high speed and is capable of being used with any pulsed (coherent or non-coherent) weather radar.

Abstract: A technique for processing the IF portion of a radar return signal in order o produce a continuous voltage output which voltage is proportional to the instantaneous frequency of the received signal. The technique employs an amplitude limiter and a wideband discriminator comprised of a delay line and phase detector followed by a video amplifier for processing the desired output signal. The output signal is indicative of velocity of precipitation in the radar target range. This information may be employed to detect and measure the degree and intensity of precipitation fall velocities, winds within a storm and other velocity dependent characteristics.

Abstract: A waveform generator particularly suited for the simulation of Doppler ra returns from precipitation is provided. Also, waveform pattern selected capability is provided and spectral shapes such as Gaussian distributions, symmetrical and asymmetrical bimodal spectral shapes or flat spectra can be chosen and generated. The device is portable and capable of being used in the field.

Abstract: In a computer-assisted tomography (CAT) apparatus, in which a fan-shaped X-ray distribution is rotated about the patients body, it is possible to use a ring of stationary detectors disposed to receive the radiation after passage through the body. In this arrangement the ring of detectors is of smaller radius than the locus of motion of the radiation source. It would appear that this would cause the detectors to obscure the body from the radiation. An arrangement disclosed moves out of the radiation beam those detectors which would present an obstruction so that only those required to collect radiation lie in the beam.