Abstract: The invention relates to an AIS data transmission method using AIS standard-compliant AIS signals. The AIS data (5) to be transmitted is converted into AIS signals on the transmitter side and transmitted via a main channel (41). The AIS signals are received in an AIS receiver (2, 3) and converted back into received AIS data (6, 7). Error-correcting redundancy data is generated from the AIS data (5) to be transmitted or from parts of said data on the transmitter side, and the redundancy data can be used on the receiver side to correct errors of the received AIS data (6, 7). The redundancy data is converted into redundancy signals on the transmitter side and transmitted via an auxiliary channel (42) provided in addition to the main channel (41). The invention further relates to a corresponding AIS transmitter, a corresponding AIS receiver, and an AIS transceiver. The invention further relates to a system consisting of AIS transmitters and AIS receivers and to a computer program.

Abstract: The invention relates to an AIS data transmission method using AIS standard-compliant AIS signals. The AIS data (5) to be transmitted is converted into AIS signals on the transmitter side and transmitted via a main channel (41). The AIS signals are received in an AIS receiver (2, 3) and converted back into received AIS data (6, 7). Error-correcting redundancy data is generated from the AIS data (5) to be transmitted or from parts of said data on the transmitter side, and the redundancy data can be used on the receiver side to correct errors of the received MS data (6, 7). The redundancy data is converted into redundancy signals on the transmitter side and transmitted via an auxiliary channel (42) provided in addition to the main channel (41). The invention further relates to a corresponding AIS transmitter, a corresponding AIS receiver, and an AIS transceiver. The invention further relates to a system consisting of AIS transmitters and AIS receivers and to a computer program.

Abstract: The Method for transmitting a signal from a transmitter in an area around the transmitter via a satellite comprising the steps of transmitting a first signal having a first frequency from the transmitter to a satellite having a retrodirective antenna array comprising receiving antennas and transmitting antennas, receiving the signal transmitted from the transmitter by the receiving antennas of the retrodirective antenna array as first signals wherein the first signals received by the receiving antennas have a phase relation among each other defined by the geometric arrangement of the receiving antennas, and retrodirectively re-transmitting second signals from the transmitting antennas of the antenna array of the satellite in the direction towards the transmitter in the form of a beam with the transmitter located substantially in the center of the beam wherein the second signal has a second frequency different from the first frequency and wherein the phase relations among the second signal transmitted from

Abstract: The Method for transmitting a signal from a transmitter in an area around the transmitter via a satellite comprising the steps of transmitting a first signal having a first frequency from the transmitter to a satellite having a retrodirective antenna array comprising receiving antennas and transmitting antennas, receiving the signal transmitted from the transmitter by the receiving antennas of the retrodirective antenna array as first signals wherein the first signals received by the receiving antennas have a phase relation among each other defined by the geometric arrangement of the receiving antennas, and retrodirectively re-transmitting second signals from the transmitting antennas of the antenna array of the satellite in the direction towards the transmitter in the form of a beam with the transmitter located substantially in the center of the beam wherein the second signal has a second frequency different from the first frequency and wherein the phase relations among the second signal transmitted from

Abstract: Disclosed is a communication system (1) for advantageous use in a global emergency call/warning system, comprising at least one communication device (20, 21, 22) and a central device (10) that is connected to said communication device (20, 21, 22) in order to exchange text data. The connection between the communication device (20, 21, 22) and the central device (10) is established via at least one satellite (30). Data transmitted by the communication device (20, 21, 22) contains additional information about the current position of the communication device (20, 21, 22), or data transmitted by the central device (10) contains additional information about the local relevance of the text data.