Abstract: The invention relates to a transmitter identification system, which utilizes an identification signal embedded into a digital television signal, enabling the transmitter of origin to be identified at a receiving station. Ideally the identification signal is an orthogonal pseudo-random sequence time synchronized to the signal frame structure of the digital television signal. Particularly designed for single frequency networks, identification of the various transmitted signals enables the network to be tuned to eliminate or minimize multi-path effects at certain locations, which receive transmissions from various transmitters.

Abstract: The invention relates to a transmitter identification system, which utilizes an identification signal embedded into a digital television signal, enabling the transmitter of origin to be identified at a receiving station. Ideally the identification signal is an orthogonal pseudo-random sequence time synchronized to the signal frame structure of the digital television signal. Particularly designed for single frequency networks, identification of the various transmitted signals enables the network to be tuned to eliminate or minimize multi-path effects at certain locations, which receive transmissions from various transmitters.

Abstract: The invention relates to a method and system for tiered digital broadcasting. A plurality of different bit streams representing digital data targeted for different services is received from a data source. Each bit-stream of the plurality of different bit-streams is modulated on a plurality of OFDM sub-carriers. Sub-carriers of different bit streams have different spectral efficiency. The parallel OFDM sub-carriers of each bit-stream are frequency interleaved with the parallel OFDM sub-carriers of the other bit streams of the plurality of different bit streams such that the parallel OFDM sub-carriers of each bit are spread over an entire available frequency spectrum. The interleaved sub-carriers are transformed into time domain for providing a frequency interleaved OFDM signal. The OFDM signal is then upconverted to the frequency of a broadcasting channel and transmitted. The invention enables a broadcasting station to transmit multiple bit streams with different spectral efficiency using one RF channel.

Abstract: The invention relates to a transmitter identification system, which utilizes an identification signal embedded into a digital television signal, enabling the transmitter of origin to be identified at a receiving station. Ideally the identification signal is an orthogonal pseudo-random sequence time synchronized to the signal frame structure of the digital television signal. Particularly designed for single frequency networks, identification of the various transmitted signals enables the network to be tuned to eliminate or minimize multi-path effects at certain locations, which receive transmissions from various transmitters.

Abstract: The invention relates to a transmitter identification system, which utilizes an identification signal embedded into a digital television signal, enabling the transmitter of origin to be identified at a receiving station. Ideally the identification signal is an orthogonal pseudo-random sequence time synchronized to the signal frame structure of the digital television signal. Particularly designed for single frequency networks, identification of the various transmitted signals enables the network to be tuned to eliminate or minimize multi-path effects at certain locations, which receive transmissions from various transmitters.

Abstract: The present invention relates to a method and system for tiered digital broadcasting. A plurality of different bit streams representing digital data targeted for different services is received from a data source. Each bit-stream of the plurality of different bit-streams is modulated on a plurality of OFDM sub-carriers. Sub-carriers of different bit streams have different spectral efficiency. The parallel OFDM sub-carriers of each bit-stream are frequency interleaved with the parallel OFDM sub-carriers of the other bit streams of the plurality of different bit streams such that the parallel OFDM sub-carriers of each bit-stream are spread over an entire available frequency spectrum. The interleaved sub-carriers are transformed into time domain for providing a frequency interleaved OFDM signal. The OFDM signal is then upconverted to the frequency of a broadcasting channel and transmitted.

Abstract: A braking device for a railroad vehicle including traction bars is arranged to apply a braking pad on a braking surface affixed to a wheel of the vehicle. The braking device includes a reaction member, at least one lever arranged to cooperate with the reaction member, connecting devices between the traction bars means and the lever, the braking pad being borne by the lever to be applied on the braking surface by pivoting the lever under the action of the traction bars and of the reaction member.

Abstract: The invention relates a braking device for a railroad vehicle including traction structure (1, 2) arranged to apply a braking pad on a braking surface affixed to a wheel of the vehicle. It includes a reaction member (11, 20), at least one lever (6; 6', 6"; 33, 33') arranged to cooperate with the reaction member, connecting structure (23, 41) between the traction structure and the lever, the braking pad being borne by the lever to be applied on the braking surface by pivoting of the lever under the action of the traction structure and of the reaction member.

Abstract: A process for assembling two facing extremities of members of detachable links and the detachable link formed by the process wherein two facing extremities of members are assembled using two half-shells joined by assembly components according to the following steps:forming reliefs either on the inside surface of the half-shells, or on the outside surface of the member extremities with the other surface remaining smooth;mounting the two half-shells on the member extremities;forging reliefs on the initially smooth components by direct stamping onto the components displaying the reliefs;joining the two half-shells by the said assembly components.