Abstract: A frequency synthesizer includes a phase detector for comparing a reference frequency with a feedback frequency, a filter connected to the phase detector for permitting the passage of low frequency therethrough, a voltage controlled oscillator connected to the filter, a multistage frequency converter for receiving the oscillator signal from the voltage controlled oscillator as an input, and a divider for dividing the output of the multistage frequency converter to form the feedback frequency. The multistage frequency converter includes a plurality of frequency converters connected in series or parallel to each other, each of the frequency converters being adapted to perform a non-integer division. The division ratio can be set arbitrarily and finely. Thus, the feedback frequency inputted to the phase detector can be maintained constant and yet higher, irrespectively of the output frequency of the frequency synthesizer.

Abstract: An adaptive filter system has a first and a second filter subsystem of like construction, each having a series of delay elements for imparting a unit delay of one sampling interval to successive input samples in order to concurrently obtain a set of input samples of different sampling times. Each set of input samples are multiplied by respective coefficients, and the resulting values are added together for comparison with a reference signal. The coefficients are updated for each new set of input samples. For such updating, the first subsystem uses the step gain that is fixed at one, whereas the step gain used by the second subsystem is varied with time for faster convergence and smaller convergence error.

Abstract: An adaptive digital filter has a series of delay elements for imparting a unit delay of one sampling interval to successive input data samples in order to concurrently obtain a set of data samples of different sampling items. Each set of data samples are multiplied by respective coefficients, and the resulting multiplier outputs are added together into a filter output for comparison with a reference signal. The coefficients are renewed a preassigned number of times during each sampling interval, and the last renewed coefficients are used for each new set of data samples. For such coefficient renewal, a plurality of arithmetic circuits are connected in parallel for simultaneously performing the necessary computations for the renewal of all the coefficients.

Abstract: A heating apparatus for hyperthermia utilizes electromagnetic waves for locally heating cancerous cells within a living body. Electromagnetic waves output from a single electromagnetic wave generating means are branched into a plurality of branched electromagnetic waves, which are respectively employed to conduct hyperthermia treatments for a plurality of patients. The whole of the hyperthermia system is controlled in a concentrated fashion from a single section by means of time-division multiplexing. It is therefore possible for a plurality of patients to be subjected to hyperthermia treatment at the same time and in parallel with each other, even when the conditions of these patients differ from one another. Further, it is advantageously possible to simplify the arrangement of the system as a whole and stabilize the control of the system.

Abstract: A heating apparatus for hyperthermia utilizes electromagnetic waves for locally heating cancerous cells within a living body. When it is necessary for a plurality of patients to be subjected to hyperthermia treatment at the same time and in parallel with each other, the control of a plurality of electromagnetic wave outputs and the control of cooling of the surface of a heated region are effected by a centralized control which employs time-division multiplexing. Thus, it is advantageously possible to efficiently carry out a hyperthermia treatment which is fitting for the condition of each of a plurality of patients.

Abstract: A heating apparatus for hyperthermia utilizes electromagnetic waves for locally heating cancerous cells within a living body. Electromagnetic waves output from a single electromagnetic wave generating means are branched into a plurality of branched electromagnetic waves, which are respectively employed to conduct hyperthermia treatments for a plurality of patients. The whole of the hyperthermia system is controlled in a concentrated fashion from a single section by means of time-division multiplexing. It is therefore possible for a plurality of patients to be subjected to hyperthermia treatment at the same time and in parallel with each other, even when the conditions of these patients differ from one another. Further, it is advantageously possible to simplify the arrangement of the system as a whole and stabilize the control of the system.

Abstract: A heating apparatus for hyperthermia utilizes electromagnetic waves for locally heating cancerous cells within a living body. Electromagnetic waves output from a single electromagnetic wave generating device are branched into a plurality of electromagnetic wave outputs, which are respective employed to conduct hyperthermia treatments for a plurality of patients, the level of each of the branched outputs being adjustable. The whole of the hyperthermia system is controlled in a concentrated fashion from a single section by way of time-division multiplexing. It is therefore possible for a plurality of patients to be subjected to hyperthermia treatment at the same time and in parallel with each other, even when the conditions of these patients differ from one another. Further, it is advantageously possible to simplify the arrangement of the system as a whole and provide an even more precise control of the system.