Abstract: In a general aspect, a method for transmitting data by inductive coupling can include applying, at a rate of a data-carrying signal, a plurality of bursts of a periodic signal to a tuned inductive antenna circuit. The method can further include producing, in the tuned inductive antenna circuit, an antenna signal, the antenna signal generating a magnetic field. The method can further include delimiting an amplitude of each burst of the plurality of bursts of the periodic signal in accordance with an envelope signal, the envelope signal having a rising edge and a falling edge. The delimiting can include shaping the falling edge of the envelope signal using one of a digital shaping circuit and an analog shaping circuit, such that a slope of the falling edge of the envelope signal is flattened as compared to a square envelope signal.

Abstract: A data communication method between a first communication user arranged at a motor vehicle and a second communication user arranged outside the motor vehicle is provided. The first communication user can be addressed by the second communication user by way of a network address. The network address of the first communication user is defined by an address management unit arranged outside the motor vehicle and is transmitted to the first communication user.

Abstract: A digital goniometer and steering method are provided which may be used, in a preferred embodiment, for producing a figure-eight antenna reception pattern oriented at any selectable angle. The digital goniometer works with the signals from a pair of orthogonal antenna loops. In a presently preferred embodiment a first register and a second register are provided for a respective first variable gain amplifier and a second variable gain amplifier. The first and second registers receive from software a digital value related to a sine function and cosine function of the selectable angle. The first and second registers are utilized to set the gain of the first and second variable gain amplifiers. The outputs of the first and second variable gain amplifiers are added to produce the reception signal.

Abstract: A radiocommunications and localization device of the type comprising an array of antennas coupled respectively to a goniometer device and a radio receiver delivering phonic signals to an operator respectively on two headphones. This device includes a device to identify the position of the operator's head and a device for the generation of phonic signals that is coupled to the goniometer device, the radio receiver and the identifying device for the application, respectively to the headphones, of the mutually phase-shifted phonic signals so as to give the operator the impression that the phonic signal that he hears is coming from the direction of arrival of the radiowaves determined by the goniometer device. The applications of this device relate to the radio-localization of persons moving in groups.

Abstract: In order to determine the direction of a beam antenna, at least one magnetic detection device is attached to the beam antenna for measuring at least one of the horizontal and vertical components of the geomagnetic field. Maximum and minimum geomagnetic field data values are obtained from the magnetic detection devices while rotating the beam antenna. Based on output data from the at least one magnetic detection means, one or two possible direction candidates are determined. When the output data has only one possible direction candidate it is either a maximum or minimum value. The direction of the beam antenna is determined from the two direction candidates by specifying one of the candidates depending upon whether a direction of the beam antenna is to the right or left, and determining the direction of the beam antenna from one direction candidate when the output data from the at least one magnetic detection devices corresponds to the minimum or maximum geomagnetic field data.

Abstract: An improved apparatus and method for radio direction finding is set forth, the generic function of which is that of an "automatic bearing indicator" (ABI). The technique and apparatus are intended for use in association with an antenna system which provides two directional beams which are scanned azimuthally in synchronism and are accessible simultaneously at two separate ports. The first beam is characterized by a response pattern having two adjacent, equal, lobes separated by a single, simple, null. The second beam is characterized by a response pattern having a single lobe, aligned in angle with the null of the first beam. The two signals from the two ports of the antenna system are directed via a twin channel receiving means, phase difference and amplitude detection means, and analog to digital conversion means, to data processing means under control of an algorithm which exploits the properties of the phasor (complex number) ratio of the first signal to the second signal.

Abstract: Described herein is a system providing an electronic null-seeking goniometer for use in automatic direction finding equipment. A microprocessor is used to generate sine and cosine information in response to the detected phase of the bearing signal. The microprocessor iteratively locates the transmitter in the null of the cardioid response pattern of the loop and sense antennas, without rotating either the loop and sense antenna set or the goniometer. This eliminates the requirement for moving antenna and goniometer components and is constructed entirely devoid of any rotating machinery. A loop feedback signal functionally related to the detected null angle provides a stable null location method, without audio distortion, at relatively high feedback/signal ratios.