Abstract: Method for the protection of electric motors from critical operating states wherein, as the electric motor is operating, a motor current value and/or a motor voltage value is/are measured and compared with a permissible operating range wherein an output signal is generated when leaving the permissible operating range and, while the electric motor is operating, the permissible operating range is determined and adjusted continuously from the measured motor current value and/or from the measured motor voltage value.

Abstract: A measurement circuit according to the invention for temperature monitoring has a quantitative temperature sensor and at least one qualitative temperature sensor, the quantitative temperature sensor and the at least one qualitative temperature sensor being connected in series, the quantitative temperature sensor having a consistent characteristic line which increases in a strictly monotonous manner or a consistent characteristic line which decreases in a strictly monotonous manner and being dedicated to the precise temperature measurement, and the qualitative temperature sensor having a nominal response temperature at which the resistance value changes in a non-linear manner and being dedicated to the monitoring of limit temperatures.

Abstract: Process for regulating a compressor with motor for a refrigerating system, where the temperature of the cooling site is regulated through an on-off motor mode if the temperature in the compressor exceeds an upper temperature threshold. In addition, the temperature of the cooling site is regulated through a continuous on mode of the motor as soon as the motor has cooled to a lower temperature threshold. The controller converts a variable corresponding to the cooling requirement of the cooling site into a switch signal for a valve, which results in clocked opening and closing of the valve, or uses a frequency converter, which controls the cooling liquid flow through the compressor by regulating the voltage and the frequency of the motor in that the frequency converter converts a variable corresponding to the cooling requirement of a cooling site into a voltage and a frequency for the motor.

Abstract: In a method for operating an asynchronous motor including a main winding and an auxiliary winding, a start capacitor is connected in series with the auxiliary winding before the asynchronous motor is started up and is disconnected at a point in time, which is to be determined, after the asynchronous motor is started up. The voltage of the auxiliary winding is measured and at least one mathematical model is used, which models the voltage amplitude of the voltage of the auxiliary winding in relation to time and includes at least one parameter of the dynamic process of the motor starting procedure, which is determined on the basis of the mathematical model and the course of the amplitude or the effective value of the measured voltage of the auxiliary winding, and the point in time for disconnecting the start capacitor is determined by means of the determined parameter.

Abstract: A transmitter comprises a first spreading unit configured to multiply each of multiple data symbols with a first spreading code sequence of a first spreading factor; a compression and repetition unit configured to compress output signals of the first spreading unit in time domain and repeat the compressed signal L times (where L is a natural number greater than or equal to 2); a phase modulation unit configured to multiply the compressed and repeated signal with a user dependent phase and output a data block consisting of L sub-blocks; a second spreading unit configured to replicate the data block according to a second spreading factor and multiply each set of the replicated sub-blocks with a second spreading code sequence of the second spreading factor to produce a two-dimensionally spread signal; and a wireless transmission unit configured to transmit the two-dimensionally spread signal using a single-carrier transmission scheme.

Abstract: A method of transmitting data to a receiver, wherein the data is transmitted using a plurality of sub-carriers, is provided. The method provided includes determining, for each sub-carrier and for each of a plurality of combinations of the sub-carrier and an antenna of a plurality of antennas to be used for transmitting the data, a transmission characteristic of a transmission of the sub-carrier using the antenna; and selecting, for each sub-carrier, an antenna of the plurality of antennas to be used for the transmission of the sub-carrier based on the transmission characteristic of the transmission of the sub-carrier between the antenna and the receiver.

Abstract: A transmitter comprises a first spreading unit configured to multiply each of multiple data symbols with a first spreading code sequence of a first spreading factor; a compression and repetition unit configured to compress output signals of the first spreading unit in time domain and repeat the compressed signal L times (where L is a natural number greater than or equal to 2); a phase modulation unit configured to multiply the compressed and repeated signal with a user dependent phase and output a data block consisting of L sub-blocks; a second spreading unit configured to replicate the data block according to a second spreading factor and multiply each set of the replicated sub-blocks with a second spreading code sequence of the second spreading factor to produce a two-dimensionally spread signal; and a wireless transmission unit configured to transmit the two-dimensionally spread signal using a single-carrier transmission scheme.

Abstract: A communication device is provided, the communication device comprising a receiving circuit configured to receive a message from another communication device; a time base circuit providing a time base signal that specifies a plurality of time periods; a determining circuit configured to determine, based on an expected reception time of the message and a reception time of the message, a parameter value characterizing a time base offset between the communication device and the other communication device; an offset generating circuit configured to generate a time period offset value specifying a time offset from a point in time, the time period offset value corresponding to a number of time periods from the plurality of time periods, wherein the number of time periods is determined according to the parameter value.

Abstract: A method for transmitting OFDM symbols by a plurality of ad-hoc radio communication devices in an ad-hoc radio communication devices' group is provided. The method includes a first ad-hoc radio communication device of the ad-hoc radio communication devices' group transmitting a first OFDM symbol in a first frequency sub-range of a frequency range selected for transmission in accordance with a frequency hopping pattern, the frequency range comprising a plurality of frequency sub-ranges, and in the same transmission time period, a second ad-hoc radio communication device of the ad-hoc radio communication devices' group transmitting a second OFDM symbol in a second frequency sub-range of the frequency range, wherein the second frequency sub-range is different from the first frequency sub-range.

Abstract: A method of transmitting data to a receiver, wherein the data is transmitted using a plurality of sub-carriers, is provided. The method provided includes determining, for each sub-carrier and for each of a plurality of combinations of the sub-carrier and an antenna of a plurality of antennas to be used for transmitting the data, a transmission characteristic of a transmission of the sub-carrier using the antenna; and selecting, for each sub-carrier, an antenna of the plurality of antennas to be used for the transmission of the sub-carrier based on the transmission characteristic of the transmission of the sub-carrier between the antenna and the receiver.

Abstract: A variable spreading factor-orthogonal frequency and code division multiplexing (VSF-OFCDM) system and receiver for use therein has a sequence extension remover for removing a predetermined number of chips from the received signal to form a modified signal, and a first converter for converting the modified signal from a serial sequence to a parallel sequence. A despreader is coupled to the first converter for despreading the parallel sequence to derive a group of symbols. An orthogonal transform block, such as a Fast Fourier Transform block is coupled to the despreader to transform the symbols from the time domain to the frequency domain. An equalizer block is coupled to the transform block for equalizing the transformed signal to reduce channel distortion. A deinterleaver block is coupled to the equalizer block to form a deinterleaved signal. The deinterleaved signal is then converted from a parallel sequence to a serial sequence.

Abstract: A method for transmitting data between a communication network unit and a plurality of communication devices is provided, comprising using a plurality of carrier signals grouped into at least one carrier signal group, determining a subset of communication devices of the plurality of communication devices, and using the at least one carrier signal group for data transmission between the communication network and the communication devices of the subset of communication devices.

Abstract: A method and a system are provided for detecting a code sequence in an ultra-wideband system. An on-off keying (OOK) detector is used for detecting a code sequence. A soft despreader is used for despreading the energy of the code sequence to provide a plurality of multipath energies. A RAKE combiner combines the plurality of multipath energies obtained from the soft despreader. The soft despreader and the RAKE combiner enable operation of an OOK receiver without using a timing recovery process block.

Abstract: The invention relates to a temperature tripping device for reliably shutting down a load, especially a motor, having at least one input for receiving at least one temperature-dependent sensor signal as an input signal, a first evaluation circuit for generating a first output signal if the input signal reaches a preset value, and means for generating a trip signal if the output signal is generated. In addition, a second, redundant, evaluation channel is provided which is supplied with the same input signal as the first evaluation channel and which generates a second output signal if the input signal reaches the preset value, wherein the means for generating a trip signal are connected to the two evaluation channels and generate the trip signal if at least one of the two output signals is generated.

Abstract: The invention relates to a temperature tripping device for reliably shutting down a load, especially a motor, having at least one input for receiving at least one temperature-dependent sensor signal as an input signal, a first evaluation circuit for generating a first output signal if the input signal reaches a preset value, and means for generating a trip signal if the output signal is generated. In addition, a second, redundant, evaluation channel is provided which is supplied with the same input signal as the first evaluation channel and which generates a second output signal if the input signal reaches the preset value, wherein the means for generating a trip signal are connected to the two evaluation channels and generate the trip signal if at least one of the two output signals is generated.

Abstract: A variable spreading factor-orthogonal frequency and code division multiplexing (VSF-OFCDM) system and receiver for use therein has a sequence extension remover for removing a predetermined number of chips from the received signal to form a modified signal, and a first converter for converting the modified signal from a serial sequence to a parallel sequence. A despreader is coupled to the first converter for despreading the parallel sequence to derive a group of symbols. An orthogonal transform block, such as a Fast Fourier Transform block is coupled to the despreader to transform the symbols from the time domain to the frequency domain. An equalizer block is coupled to the transform block for equalizing the transformed signal to reduce channel distortion. A deinterleaver block is coupled to the equalizer block to form a deinterleaved signal. The deinterleaved signal is then converted from a parallel sequence to a serial sequence.

Abstract: A method for providing retransmission signals using multi-carrier code division multiple access is disclosed. The method comprises receiving a serial data stream in response to the failed prior reception of the serial data stream, and converting the serial data stream to a parallel data stream, the parallel data stream having a plurality of symbols having a symbol sequence. The method also comprises performing spreading on the parallel data stream by spreading each of the plurality of symbols of the parallel data stream with a spreading code, the spreading code having a plurality of chips having a chip sequence, and performing multi-carrier modulation on the parallel data stream by modulating each of the plurality of symbols of the parallel data stream to a plurality of subcarriers and generating a plurality of modulated signals.