Abstract: A method and apparatus are described for transmitting/receiving a Gigabit-Ethernet signal by a high capacity point-to-point radio system. The basic idea consists in transmitting a Gigabit Ethernet interface using a single frequency in a channel plan of about 56 MHz bandwidth. The invention is based on a technology that combines forward error correction, cross polarization interference cancellation (XPIC), base-band signal processing, adaptive equalization and antenna's interconnection. In the best configuration, two carrier frequencies, H and V polarized, are selected in order to have the required bandwidth for easily transporting a Gigabit Ethernet. A proper compression rate can be selected according to the available resources; in case of radio channel failure, the compression rate can be changed. Ethernet frames are mapped by a Generic Framing Procedure encapsulation protocol.

Abstract: Described is a method and apparatus for mapping Fast Ethernet data interfaces (in addition to possible data interfaces of different type) into a single VC-4 Virtual Container of a STM-1/OC-3 payload transmitted to a radio-link system. The method is characterized by the steps of: packeting the Fast Ethernet signal and any other signal, mapping the packets into a single (VC-4) Virtual Container of a STM-1/OC-3 payload of a SDH/SONET signal frame, and transmitting said signal frame through the point-to-point radio-link, said radio link being a point-to-point SDH/SONET radio link. All the packets have the same format and are associated to a header for identifying the source. The interfaces of different type are conveniently grouped. Possibly, the VC-4 is filled with null packets to exhaust the maximum available capacity.

Abstract: Described is a method and system for increasing the spectrum efficiency in a radio transmission system. Advantageously, the interference phenomenon is used for transmitting two different signals, by utilizing for each of them carriers at the same frequency, thus obtaining in this way a doubling of the spectrum efficiency. Practically, the same signal is transmitted by two different antennas in order to have two coherent signal sources. On the receiving front, there are points of maximum and minimum of this signal. If the original signal is properly phase shifted with an antenna vis-à-vis the other one, the effect will be to arrange the maxima and minima on the receiving front in a corresponding way. The present invention allows for the use of dual polarization antennas (H and V or any other type of orthogonal polarization) to obtain a still higher spectrum efficiency.

Abstract: A method and device is described for converting an STM-1 signal into a sub-STM-1 signal in synchronous radio transmission. The invention provides for the use of a pure regenerator network element without any multiplexing function. The method according to the invention provides in transmission, for reducing the received STM-1 signal by one third (only the first TUG-3 is considered as valid and is transmitted in the radio link, whereas the second and the third TUG-3 are considered in an unequipped condition and are not transmitted), thus maintaining the STM-1 structure. In reception, the method provides for reconstructing the signal with the complete regenaration of the payload and the correct structure of the AU-4 without incurring any parity control infringement.

Abstract: A method is described for transmitting/receiving STM-4 (SDH) or STS-12 (SONET) digital signals over two RF carriers in a radio regenerator section. The method provides for performing, in transmission, a de-interleaving operation of the standard frame to be transmitted in such a way as to subdivide it by columns into two sub-frames. The RSOH bytes of the standard frame are terminated and transmitted over the two working channels or over one service channel and one working channel so as to be protected in a 1+1 configuration: In reception, a column interleaving operation recombines together the two sub-frames and recovers and correctly rearranges the RSOH bytes so terminated as to obtain the standard frame originally received from the transmitter. The generated sub-frames are synchronized with the standard frame.

Abstract: A method is described for detecting a drop in the power received in an optical receiver for free-space optical telecommunications systems and for identifying the cause of said drop in power received. The method envisages the steps of obtaining a value of power relating to the signal required on the optical axis of the receiver; of obtaining at least two additional values of power in opposite areas in respect of said optical axis; and of calculating a difference in power between said at least two additional values of power. Said difference in power is indicative of the cause of the drop in power. Once the cause of the drop in power has been determined, the appropriate countermeasures will be undertaken.

Abstract: Described is a method and system for increasing the spectrum efficiency in a radio transmission system. Advantageously, the interference phenomenon is used for transmitting two different signals, by utilizing for each of them carriers at the same frequency, thus obtaining in this way a doubling of the spectrum efficiency. Practically, the same signal is transmitted by two different antennas in order to have two coherent signal sources. On the receiving front, there are points of maximum and minimum of this signal. If the original signal is properly phase shifted with an antenna vis-à-vis the other one, the effect will be to arrange the maxima and minima on the receiving front in a corresponding way. The present invention allows for the use of dual polarization antennas (H and V or any other type of orthogonal polarization) to obtain a still higher spectrum efficiency.

Abstract: A method and apparatus are described for transmitting/receiving a Gigabit-Ethernet signal by a high capacity point-to-point radio system. The basic idea consists in transmitting a Gigabit Ethernet interface using a single frequency in a channel plan of about 56 MHz bandwidth. The invention is based on a technology that combines forward error correction, cross polarization interference cancellation (XPIC), base-band signal processing, adaptive equalization and antenna's interconnection. In the best configuration, two carrier frequencies, H and V polarized, are selected in order to have the required bandwidth for easily transporting a Gigabit Ethernet. A proper compression rate can be selected according to the available resources; in case of radio channel failure, the compression rate can be changed. Ethernet frames are mapped by a Generic Framing Procedure encapsulation protocol.

Abstract: Described is a method and apparatus for mapping Fast Ethernet data interfaces (in addition to possible data interfaces of different type) into a single VC-4 Virtual Container of a STM-1/OC-3 payload transmtited to a radio-link system. The method is characterized by the steps of: packeting the Fast Ethernet signal and any other signal, mapping the packets into a single (VC-4) Virtual Container of a STM-1/OC-3 payload of a SDH/SONET signal frame, and transmitting said signal frame through the point-to-point radio-link, said radio link being a point-to-point SDH/SONET radio link. All the packets have the same format and are associated to a header for identifying the source. The interfaces of different type are conveniently grouped. Possibly, the VC-4 is filled with null packets to exhaust the maximum available capacity.

Abstract: A hybrid through-air telecommunication system of a radio/optical type is described which significantly reduces the annual unavailability caused by weather events and/or faults. The hybrid optical and radio system further permits, given an annual availability value, of significantly increasing the maximum link distance if compared with the full radio or full optic systems. The changeover in reception occurs on the basis of the power values of the received signals.

Abstract: A method is described for transmitting/receiving STM-4 (SDH) or STS-12 (SONET) digital signals over two RF carriers in a radio regenerator section. The method provides for performing, in transmission, a de-interleaving operation of the standard frame to be transmitted in such a way as to subdivide it by columns into two sub-frames. The RSOH bytes of the standard frame are terminated and transmitted over the two working channels or over one service channel and one working channel so as to be protected in a 1+1 configuration: In reception, a column interleaving operation recombines together the two sub-frames and recovers and correctly rearranges the RSOH bytes so terminated as to obtain the standard frame originally received from the transmitter. The generated sub-frames are synchronized with the standard frame.

Abstract: A method and device is described for converting an STM-1 signal into a sub-STM-1 signal in synchronous radio transmission. The invention provides for the use of a pure regenerator network element without any multiplexing function. The method according to the invention provides in transmission, for reducing the received STM-1 signal by one third (only the first TUG-3 is considered as valid and is transmitted in the radio link, whereas the second and the third TUG-3 are considered in an unequipped condition and are not transmitted), thus maintaining the STM-1 structure. In reception, the method provides for reconstructing the signal with the complete regenaration of the payload and the correct structure of the AU-4 without incurring any parity control infringement.