Abstract: A bidirectional wireless communication system includes: a first wireless communication apparatus for bidirectional communication configured to multiplex a modulated signal obtained by modulating an input signal by a reference carrier signal having a predetermined carrier frequency, and transmit a resultant transmission signal; and a second wireless communication apparatus, having an oscillator configured to oscillate a signal having a free-running oscillation frequency, configured to inject a reception signal received from the first wireless communication apparatus into the oscillator, receive the reception signal while variably controlling the free-running oscillation frequency of the oscillator of the second wireless communication apparatus, detect whether the free-running oscillation frequency of the signal of the oscillator of the second wireless communication apparatus has entered the frequency range up to the injection locking to be frequency-locked with a carrier frequency of the injected reception sig

Abstract: A method for establishing a wireless communication link between a first communication device having a beam antenna to be steered to different positions and a second communication device. The method includes transmitting a link request signal from the first communication device to the second communication device via the beam antenna. The link request signal includes information relating to a current position of the beam antenna. The method further includes obtaining, in case the link request signal is received in the second communication device, channel quality information representative of a current transmission path.

Abstract: The present invention relates to a method for transmitting signals in a wireless communication system, in which signals are transmitted from a first communication device to a second communication device, said signals being transmitted in consecutive frames, each frame having a preamble section including preamble information, at least one of said first and said second communication devices having a narrow beam antenna which is adapted to be steered to different positions, each of said different positions corresponding to one of a number of different transmissions paths from said to said second communication device, including the steps of transmitting and receiving a first preamble section including preamble information enabling the estimation of a channel quality of a current transmission path, while said narrow beam antenna is in a current position corresponding to said current transmission path, steering said narrow beam antenna from said current position to a different position corresponding to a candidate

Abstract: A communication system including a first station having at least two first narrow beam antennas and a second station having at least two second narrow beam antennas. The first and second stations establish a first communication path for wireless communication via a pair of first and second narrow beam antennas. When communication via the first communication path is disturbed by obstacles, the first and second stations automatically establish at least one alternative communication path, which is spatially different from the first communication path, for wireless communication using the at least two first narrow beam antennas and the at least two second narrow beam antennas.

Abstract: A communication system including a first station having at least two first narrow beam antennas and a second station having at least two second narrow beam antennas. The first and second stations establish a first communication path for wireless communication via a pair of first and second narrow beam antennas. When communication via the first communication path is disturbed by obstacles, the first and second stations automatically establish at least one alternative communication path, which is spatially different from the first communication path, for wireless communication using the at least two first narrow beam antennas and the at least two second narrow beam antennas.

Abstract: A frequency-shift-keying demodulator including a phase shifter for shifting the phase of an input signal by a predetermined degree and outputting a shifted signal, a combining unit for combining the input signal and the shifted signal and for outputting a corresponding signal, and a low-pass filter for filtering the signal output by the combining unit and outputting a low-pass filtered signal, the bandwidth of the low-pass filter being matched with the bandwidth of a data signal included in the input signal, such that the combining unit includes at least one adder for adding the input signal and the shifted signal, and outputting an added signal, and at least one square law detector for receiving the added signal output by the adder and outputting a squared signal which is the square of the added signal, wherein the combining unit outputs the squared signal to the low-pass filter.

Abstract: The present invention comprises a method for establishing a wireless communication link between a first communication device (1) having a narrow beam antenna (2) adapted to be steered to different positions and a second communication device (10), comprising the steps of transmitting a link request signal from said first communication device (1) to said second communication device (10) via said narrow beam antenna, wherein said link request signal comprises information relating to a current position of the narrow beam antenna, and obtaining, in case said link request signal is received in said second communication device (10), channel quality information representative of a current transmission path. The invention further comprises a transmitting device and a receiving device for executing said method.

Abstract: The present invention relates to a signal generator and signal processor for single carrier wireless communication systems with frequency domain equalizer, which are operable to use pseudorandom-noise sequences as part of a preamble and possibly as cyclic prefix. The different arrangements and examples of said pseudorandom-noise sequences could be used for coarse timing synchronization, channel estimation, carrier synchronization, signal-noise-ratio estimation and channel equalization.

Abstract: The present invention comprises a method for establishing a wireless communication link between a first communication device (1) having a narrow beam antenna (2) adapted to be steered to different positions and a second communication device (10), comprising the steps of transmitting a link request signal from said first communication device (1) to said second communication device (10) via said narrow beam antenna, wherein said link request signal comprises information relating to a current position of the narrow beam antenna, and obtaining, in case said link request signal is received in said second communication device (10), channel quality information representative of a current transmission path. The invention further comprises a transmitting device and a receiving device for executing, said method.

Abstract: The present invention relates to the fields of link adaption, multi-path communication, non-line of sight wireless communication. The present invention especially relates to a communication system, a communication device and a communication method. The problem to be solved by the present invention is to reduce the time which is necessary for the adaption to a specific communication path in a communication system.

Abstract: The present invention relates to a method for transmitting signals in a wireless communication system, in which signals are transmitted from a first communication device to a second communication device, said signals being transmitted in consecutive frames, each frame having a preamble section including preamble information, at least one of said first and said second communication devices having a narrow beam antenna which is adapted to be steered to different positions, each of said different positions corresponding to one of a number of different transmissions paths from said to said second communication device, including the steps of transmitting and receiving a first preamble section including preamble information enabling the estimation of a channel quality of a current transmission path, while said narrow beam antenna is in a current position corresponding to said current transmission path, steering said narrow beam antenna from said current position to a different position corresponding to a candidate

Abstract: The invention relates to a wireless optical data transmission system and a method for wireless optical transmission of data. The system comprises a data stream generator for generating at least two parallel data streams (18.1, 18.2, 18.3). The parallel data streams are transmitted by a number of separate optical transmitting devices (8, 9, 10) separately by emitting first optical signals. The system further comprises a corresponding number of detectors (19, 20, 21) for detecting the first optical signals and converting them into respective second signals (26.1, 26.2, 26.3) and an error correction unit (31) for correcting the amended second signals. Within a predistortion (29) unit each second signal (26.1, 26.2, 26.3) is amended individually with respect to a transmission channel used.

Abstract: The present invention provides a short-range wireless mobile communication system with a first terminal and a mobile terminal that are each adapted for transmitting and receiving an information carrying signal wave, whereby at least the first terminal or the mobile terminal comprise a directional signal wave converter for transmitting and/or receiving the information carrying signal wave with a directional characteristic and a control means for controlling the directional characteristic according to a position of the mobile terminal relative to the first terminal.

Abstract: The present invention relates to a method for transmitting signals in a wireless communication system, in which signals are transmitted from a first communication device to a second communication device, said signals being transmitted in consecutive frames, each frame having a preamble section comprising preamble information, at least one of said first and said second communication devices having a narrow beam antenna which is adapted to be steered to different positions, each of said different positions corresponding to one of a number of different transmission paths from said first to said second communication device, comprising the steps of transmitting and receiving a first preamble section comprising preamble information enabling the estimation of a channel quality of a current transmission path, while said narrow beam antenna is in a current position corresponding to said current transmission path, steering said narrow beam antenna from said current position to a different position corresponding to a ca

Abstract: The present invention relates to a signal generator and signal processor for single carrier wireless communication systems with frequency domain equalizer, which are operable to use pseudorandom-noise sequences for cyclic prefix. The different arrangements and examples of said pseudorandom-noise sequences could be used for coarse timing synchronization, channel estimation, carrier synchronization, signal-noise-ration estimation and channel equalization.

Abstract: The present invention relates to a method for transmitting signals in a wireless communication system, in which signals are transmitted from a transmitting device (1) to a receiving device (10), at least one of said devices (1, 10) having a narrow beam antenna (2, 11) which is adapted to be steered to different positions, each of said different positions corresponding to a number of different transmission paths from said transmitting device (1) to said receiving device (10), said signals comprising a beam steering frame enabling the estimation of a channel quality of the current transmission path, comprising the steps of a) transmitting and receiving said signals subsequently via each of the plurality of transmission paths thereby allowing an estimation of channel quality of each of the plurality of transmission paths, b) selecting on basis of the estimated channel quality several transmission paths out of the plurality of transmission paths as candidates for a communication channel, c) repeating step a) at

Abstract: Wireless communication systems are provided with an adaptive subcarrier loading function for a mobile receiver in a wireless communication system based on Orthogonal Frequency Division Multiplexing (OFDM) that can advantageously be applied to predict the channel transfer function of a multipath propagation channel being severely impaired by frequency-selective fading and an extremely time-variant behavior by detecting the position and/or movement of zero points of the transfer function, thereby reducing the probability of incorrect assignment of the modulation scheme for each subcarrier caused by mobile terminals moving at high velocity. The zero points of the estimated channel transfer function are determined by detecting the position of deep notches on the associated amplitude response of the measured channel transfer function caused by frequency-selective fading whose depths are larger than a predefined threshold.

Abstract: The present invention comprises a method for establishing a wireless communication link between a first communication device (1) having a narrow beam antenna (2) adapted to be steered to different positions and a second communication device (10), comprising the steps of transmitting a link request signal from said first communication device (1) to said second communication device (10) via said narrow beam antenna, wherein said link request signal comprises information relating to a Current position of the narrow beam antenna, and obtaining, in case said link request signal is received in said second communication device (10), channel quality information representative of a current transmission path. The invention further comprises a transmitting device and a receiving device for executing, said method.

Abstract: The present invention relates to a method for transmitting signals in a wireless communication system, in which signals are transmitted from a first communication device to a second communication device, said signals being transmitted in consecutive frames, each frame having a preamble section comprising preamble information, at least one of said first and said second communication devices having a narrow beam antenna which is adapted to be steered to different positions, each of said different positions corresponding to one of a number of different transmission paths from said first to said second communication device, comprising the steps of transmitting and receiving a first preamble section comprising preamble information enabling the estimation of a channel quality of a current transmission path, while said narrow beam antenna is in a current position corresponding to said current transmission path, steering said narrow beam antenna from said current position to a different position corresponding to a ca

Abstract: It is proposed a receiver comprising receiving means for receiving a preamble signal (26) that comprises a long PN sequence (33) being a combination of a plurality of short PN sequences (29, 30, 31,32), wherein said short PN sequences (29, 30, 31,32) are selected on the basis of their auto-correlation and/or cross-correlation properties. At least one of said short PN sequences (29, 30, 31,32) referred to as a coarse timing short PN sequence (PN1) is adapted to perform a coarse timing synchronization, extracting means (41) for extracting said coarse timing short PN sequence (PN1) from said long PN sequence (33), first auto-correlating means (42, 43, 44, 45) for performing a coarse timing synchronization using said coarse timing short PN sequence (PN1), and second auto-correlating means (52, 53, 54, 55) for performing a fine timing synchronization using said long PN sequence (33).