Abstract: A calibration procedure of wireless networks to create a topology map mainly consists of two phases: a measurement phase during which each wireless device, i. e. all mobile terminals end the central controller transmits a calibration signal in broadcast mode (S2, S3, S4) and each other wireless device measures the received signal quality and the reporting phase during which each mobile terminal reports the measured results to the central controller of the network (S6, S7). Both of these phases are preferably initiated by the central controller the measurement phase with the broadcast of a measurement control signal to all mobile terminals (S1) and the reporting phase with the broadcast of a reporting control signal to all mobile terminals (S5). Based on all measurement results the central controller creates a topology map of the network once all reports have been received.

Abstract: A calibration procedure of wireless networks to create a topology map mainly consists of two phases: a measurement phase during which each wireless device, i.e. all mobile terminals end the central controller, transmits a calibration signal in broadcast mode (S2, S3, S4) and each other wireless device measures the received signal quality and the reporting phase during which each mobile terminal reports the measured results to the central controller of the network (S6, S7). Both of these phases are preferably initiated by the central controller, the measurement phase with the broadcast of a measurement control signal to all mobile terminals (S1) and the reporting phase with the broadcast of a reporting control signal to all mobile terminals (S5). Based on all measurement results the central controller creates a topology map of the network once all reports have been received.

Abstract: An OFDM telecommunication device, i.e. a receiver, transmitter or transceiver for OFDM—(Orthogonal Frequency-Division Multiplex) signals that generally employs the Inverse Fourier Transformation (IFT) technique to encode and transmit time-division multiplex signals and the Fourier Transformation (FT) technique to decode the received signals into time-division multiplex signals comprises a transformation unit (2) that incorporates at least an analog multiplication step and at least an analog convolution step of a multiplication convolution multiplication algorithm or a convolution multiplication convolution signal to perform a fourier transformation for demodulation and/or an inverse fourier transformation for modulation into the analog stage of said OFDM telecommunication device.

Abstract: The invention proposes the separate processing of the phase and amplitude of multi-amplitude digital modulation techniques, such as a QAM. The phases are differentially modulated and the amplitudes coherently processed. Also proposed is a method to correct the amplitude distortion of the symbols on each subcarrier, either from the QAM signal itself or from any PSK signal, if available. The invention shows that differential modulation/demodulation of multi-amplitude signals with no equidistant phases such as QAM is possible. Complex equalizer means to perform a channel estimation is no more needed as for coherent systems. Further, no pilot sucarriers are needed, thus the bandwidth efficiency is much higher. Furthermore, the frequency snychronization of differential demodulated signals is less complex. An implementation proposal of the new modulation/demodulation technique is described.

Abstract: A calibration procedure of wireless networks to create a topology map mainly consists of two phases: a measurement phase during which each wireless device, i. e. all mobile terminals end the central controller transmits a calibration signal in broadcast mode (S2, S3, S4) and each other wireless device measures the received signal quality and the reporting phase during which each mobile terminal reports the measured results to the central controller of the network (S6, S7). Both of these phases are preferably initiated by the central controller the measurement phase with the broadcast of a measurement control signal to all mobile terminals (S1) and the reporting phase with the broadcast of a reporting control signal to all mobile terminals (S5). Based on all measurement results the central controller creates a topology map of the network once all reports have been received.

Abstract: A transmit power control applicable for direct mode in a central controller based wireless network is described whereby direct mode indicates a direct communication of two network terminals (1, 15) without routing the traffic through the central controller (18). According to the present invention the transmit power control is performed by means of exchanging messages (S1, S2, S3) between the peer network devices (1, 15) in which recommendations for power control are carried.

Abstract: Performing an antenna diversity set-up according to the present invention a first mobile terminal (1) transmits a pre-defined antenna calibration signal to a second mobile terminal (15) using its omni-directional antenna (10). During the period of the transmitted signal the best receiving antenna (x) is identified at the second mobile terminal (15) by switching all its directional antennas (21 to 28) and its omni-directional antenna (20) into its receiving path and measuring the received signal quality, e.g. the received signal strength. The directional antenna (x) of the second network device (15) which is identified as best receiving antenna is then used for transmission and reception of data transfer with the first network device (1).

Abstract: The invention is related to an arrangement for isolation of signals between a receiving branch (RX) and a transmitting branch (TX) of a multiband radio system. Each of said branches (RX, TX) comprises at least two radio frequency filters (RF1, RF2; TF1, TF2) with a stop band function. Within each of said branches (RX, TX) each of said radio frequency filters (RF1, RF2; TF1, TF2) is adapted to a given frequency band, whereby said frequency bands are different from each other. Furtheron there are provided a receive/transmit switch (RTSW) and a receiving/transmitting filter selector (RTFS).