摘要:
A method for localizing a terminal includes transmitting the signal by the terminal; receiving the signal by a first and a second satellite; transmitting the signal from each satellite to a receiving station; demodulating the signal received by the first satellite to determine a signal content and the time of arrival of the signal transmitted by the terminal at the receiving station via the first satellite; determining the time of arrival of the signal transmitted by the terminal at the receiving station via the first and second satellite; determining a position for the terminal by triangulation.
摘要:
A method performed on-board by a satellite for processing a signal received from a terminal during a current time interval, includes receiving, during the current time interval, a main signal containing a message from a terminal, each message having a priority level; sampling the main signal to obtain samples; storing the obtained samples into the satellite memory; first demodulating the messages corresponding to the current time interval contained in the samples stored in memory; when the satellite is in the range of a ground station, transmitting to the ground station the content of the memory. The first demodulating includes, for each message of the messages contained in the samples and by priority order: demodulating and decoding the message; forwarding, using direct link or inter-satellite-link, the demodulated message to a ground station; estimating the number of remaining non-demodulated messages in the samples stored in the memory.
摘要:
A method for recovering content such as an HTML page corresponding to a URL address by a client device, includes, based on a URL address corresponding to the content, the client device checks for the presence of the content of the URL address in a cache memory of the client device; in absence of the content of the URL address in the cache memory, the client device creates a short message including the URL address; the message is transmitted to a server device by a one-way transmission protocol without establishment of a connection; the server device downloads the content corresponding to the URL address from the internet network; the content is transmitted to the client device by the server device via a one-way protocol with coding without acknowledgement; the content is received by the client device; and the content is recovered and stored by the client device in the cache memory.
摘要:
A method for generating a circular polarisation signal from at least two transponders of a satellite able to process linearly polarised signals includes: a transmission of at least two linearly polarised signal components so as to produce a circularly polarised signal by at least two transponders of a satellite; processing signals by the two transponders of the satellite to produce a circular polarisation of the signals transmitted by the satellite; ground receiving by at least one circularly polarised antenna; measuring a physical parameter from the received signals, and determining a correction parameter to be applied to the generation of the components of linearly polarised signals; generating a compensation of the components of linearly polarised signals transmitted to the satellite.
摘要:
A method for localizing a terminal includes transmitting the signal by the terminal; receiving the signal by a first and a second satellite; transmitting the signal from each satellite to a receiving station; demodulating the signal received by the first satellite to determine a signal content and the time of arrival of the signal transmitted by the terminal at the receiving station via the first satellite; determining the time of arrival of the signal transmitted by the terminal at the receiving station via the first and second satellite; determining a position for the terminal by triangulation.
摘要:
A transmission/reception installation for microwave radio signals, including a unit for transmission/reception including a receiver for receiving the electric signals from the conversion of radio signals received via a terrestrial or satellite link, referred to as forward-link signals, a demodulator for demodulating the electric signals using a first modulation/demodulation protocol, a modulator for modulating electric signals using a second modulation/demodulation protocol that is different than the first protocol, the second protocol being a spread-spectrum protocol, the modulator modulating the signals demodulated by the demodulator, and a converter for converting the electric signals modulated using a spread-spectrum protocol into radio signals that can be transmitted via a satellite link. The installation also includes one or more boxes including a modulator for modulating the electric signals using the first modulation/demodulation protocol, and a coaxial cable connecting the unit for transmission/reception to the boxes.
摘要:
A method for recovering content such as an HTML page corresponding to a URL address by a client device, includes, based on a URL address corresponding to the content, the client device checks for the presence of the content of the URL address in a cache memory of the client device; in absence of the content of the URL address in the cache memory, the client device creates a short message including the URL address; the message is transmitted to a server device by a one-way transmission protocol without establishment of a connection; the server device downloads the content corresponding to the URL address from the internet network; the content is transmitted to the client device by the server device via a one-way protocol with coding without acknowledgement; the content is received by the client device; and the content is recovered and stored by the client device in the cache memory.
摘要:
A method for locating a terminal in a coverage area using a telecommunication network, the network including a multi-beam satellite, the area including various cells, each associated with a beam for linking to the satellite to which a frequency band is assigned, the method including: performing the uplink transmission of a message incorporated into a modulated signal to the satellite at a frequency shared by three different uplink beams such that the message is received by the satellite with three different amplitudes; performing the downlink transmission of three modulated signals incorporating the message, the first, second, and third signals each corresponding to a different beam from among the three beams; receiving the first, second, and third signals; determining the amplitudes of the message within the first, second and third signals; and determining the location of the terminal from the amplitudes of the message within the first, second, and third signals.
摘要:
A method performed on-board by a satellite for processing a signal received from a terminal during a current time interval, includes receiving, during the current time interval, a main signal containing a message from a terminal, each message having a priority level; sampling the main signal to obtain samples; storing the obtained samples into the satellite memory; first demodulating the messages corresponding to the current time interval contained in the samples stored in memory; when the satellite is in the range of a ground station, transmitting to the ground station the content of the memory. The first demodulating includes, for each message of the messages contained in the samples and by priority order: demodulating and decoding the message; forwarding, using direct link or inter-satellite-link, the demodulated message to a ground station; estimating the number of remaining non-demodulated messages in the samples stored in the memory.
摘要:
A method of generating interleaved symbols in a multiplexed data steam for a satellite broadcasting application to a plurality of receivers, includes allocating a plurality of data programs to a plurality of primary multiplexers according to a load balancing scheme; encoding in each primary multiplexer a plurality of data programs according to a coding scheme at a predefined code rate for generating encoded frames; and generating super frames in each primary multiplexer.