Siemens Aktiengesellschaft

Klaus V Pieverling

Dieter Leypold

Erwin Vachenauer

Bruno Maier

Gerhard Klemt

A vehicle detectors with at least one inductive loop is used as a sensor. An oscillator circuit comprises a fixed-frequency oscillator, which is directly connected to one of the inductive loops' two terminals, for purposes of exciting said loop. In addition, a phase/amplitude controller is arranged between the fixed-frequency oscillator and the other terminal, which forms a summation point of the inductive loop to deliver a compensation signal that is derived from the transmit signal in an amplitude-controlled and phase-controlled manner. The inductive loop, the fixed-frequency oscillator and the phase/amplitude controller form a bridge circuit in which (with reference to the resulting voltage at the summation point) the transmit signal and the compensation signal add up to zero in the resting state of the inductive loop. A detection signal for the presence of a vehicle in the detection range of the induction loop is derived from a voltage at this summation point which deviates therefrom.

Vehicle detector with at least one inductive loop as a sensor, and a

A method for the comparative vector measurement of keyed radio signal pulses arriving nearly simultaneously at several radio receivers, particularly DME pulses, which can exhibit great level differences. The pulses at each receiver are individually fed to an amplifier or attenuator having an amplification or attenuation, respectively, which can be adjusted in distinct steps, whose reduction or increase, respectively, takes place automatically with the rise of the leading edge of the respective signal pulse. After passing through the respective amplifier or attenuator of the receivers, the instantaneous amplitudes of the measuring signals are measured at a specific measured time which is common to all receivers. In each receiver, an individual measuring time is ascertained in such a way that switching pulses derived from the step-wise amplification reduction of the amplifier (or the step-wise attenuation increase of the attenuator) are fed to a retriggerable monostable multivibrator having a specific holding time, during the operating sequence of which the individual measuring time of each receiver is provided. After this measuring time, or after the measuring time, to all receivers, an additional step-wise reduction in amplification or increase in attenuation at the respective receiver is blocked. An individual measuring time, selected with reference to the arrival sequence, is used as the common measuring time for the simultaneous measurement of the receiving vectors of all receivers.

Method for the comparative vector measurement of signal pulses arriving

A method for the comparative vector measurement of keyed radio signal pulses, in particular Tacan pulses, arriving nearly simultaneously at several receiving stations and which can exhibit great level differences, in which, at each receiver, the pulses are initially fed to an amplifier or attenuator having amplification or attenuation, respectively, which can be adjusted in distinct steps, which reduction or increase takes place automatically with the rise of the leading edge of the respective signal pulse. After passing through the respective amplifier or attenuator of the receivers, the instantaneous amplitudes of the measuring signals are measured at a fixed measuring time common to all receivers. In each receiver a second measuring signal is produced which is in phase quadrature with respect to the aforementioned measuring signal, the instantaneous amplitude of the second measuring signal being measured at the same time as the first measuring signal.

A circuit arrangement for the digitalization of the angle of rotation .phi. of a rotatable device which is operated at fa rotations per second, employing auxiliary voltages modulated with sin .phi. and cos .phi. of a fundamental frequency fo, which with the aid of further circuit elements are converted into a counter pulse train which indicates the angle of rotation, in which n pulses correspond to the angle of rotation of 360.degree.; wherein from two auxiliary voltages is formed a third auxiliary voltage which contains only one of the frequencies (fo+fa) or (fo-fa), which third auxiliary voltage and a comparison voltage of the frequency n.sup.. fo are conducted to a comparator circuit, comprising a D-flip-flop, with the comparison voltage being present at the D-input (preparation input) and the third auxiliary voltage being present at the clock-input, whereby the desired counter pulse train with n.sup.. fa is obtained at the output of the D-flip-flop.

Growing community of inventors

Wolfratshausen-Waldram, undefined

Klaus V Pieverling