Abstract: An interstitial applicator is provided in order to heat a localized region of living tissue by simultaneously enhancing energy passed at the end of a central conductor while cancelling signals traveling along the outside of the application by forming a gap in the outer conductor of a coaxial cable with the gap being located 1/4 wavelength from the end of the outer conductor. The width of the gap corresponds to 1/3 of the diameter of the coaxial cable which forms the applicator. This system provides for an enhancement of the heating at the particular area around the tip of the central conductor while at the same time forms a block to stop surface wave heat from travelling back to the skin/tissue surface.

Abstract: A radio frequency transmission system contains at least one coherently modulated information signal, for example, a T.V. signal. At a transmission, the information signal is combined with two pilot tones, F1 and F2, related by the equation F1=N/M F2, where N and M are integers. The combined signal is suppressed-carrier modulated at microwave frequencies and transmitted to a receiver. At the receiver, the signals are demodulated by a local oscillator. The two pilot tones are then separated from the information signal and are compared to each other. The local oscillator frequency is controlled in response to this comparison such that the pilot tones at the receiver bear the same relationship to each other that they had at the transmitter. When this is achieved, the local oscillator frequency is the same as the suppressed-carrier frequency and co-channel interference is prevented.

Abstract: A microwave transmitter comprises a signal modulator for receiving an input signal that includes up to 75 video and audio channels and producing an amplitude modulated signal in the microwave frequency range corresponding thereto. An amplifier responsive to the microwave frequency signal produces an amplified output signal suitable for transmission to a remote location. The signal modulator and the amplifier have upper power limits which are sufficiently below their respective two-tone third order intermodulation intercept points that the carrier-to-triple-beat power ratios of each are respectively at least equal to first predetermined values. The gain of the amplifier is high enough that, notwithstanding the power limitation imposed on the microwave frequency signal by virtue of the upper power limit of the signal modulating means, the power of the amplified output signal is at least equal to a second predetermined value.

Abstract: An intense electric field is employed as the external source of energy in carrying to a spectroscopic analysis of a chemical composition. The substance to be analyzed is placed between an insulated conductive electrode and a ground reference. A high voltage is then applied to the electrode to generate an electric field of a predetermined intensity within the test sample. As a result of the energy absorbed, the constituents of the sample are caused to release their characteristic spectral emissions. These emissions are optically filtered to isolate the wavelength of interest which is passed to a light detector and registered on a photon counting system. The procedure is especially and uniquely applicable for conducting an in situ chemical analysis of human sweat, thus offering a valuable aid in the diagnosis of various medical abnormalities.