Space system and method for wireless communication by transmitting radiofrequency and optical signals on a return channel

A communication station configured to receive, through an optical transmission channel, an optical signal from a satellite and associated with a plurality of initial data frames T0-q, wherein said communication station comprises:

• a demodulation unit configured to demodulate said received optical signal, thereby providing M demodulated interleaved data frames I*2-m;
• a deinterleaving unit configured to deinterleave the M demodulated interleaved data frames I*2-m, thereby providing a plurality of N deinterleaved data frames B*2-n;
• a decoding unit configured to apply a reciprocal function of an error correction code to said deinterleaved data frames B*2-n, thereby providing a plurality of N decoded data frames B*1-n, each frame B*1-n comprising a set of digitized soft values;
• and
• a decoding unit configured to apply a digitized soft value decoding function to the set of N decoded data frames B*1-n, thereby providing a plurality of N regenerated data frames T*0-n, each regenerated data frame T*0-n corresponding to a reconstituted initial data frame T0-n.

A method for transmitting an optical signal, the method being implemented in a communication satellite connected to an optical transmission channel, the method comprising the following steps:

• receiving at least one modulated and encoded radiofrequency signal;
• applying soft demodulation to said at least one received radiofrequency signal in order to determine a plurality of N intermediate demodulated data frames B1-n, each frame B1-n comprising a set of digitized soft values;
• applying an error correction code to said intermediate demodulated data frames B1-n in order to determine a plurality of N encoded intermediate demodulated data frames B2-n;
• applying an interleaving function to said encoded intermediate demodulated data frames B2-n in order to determine M interleaved data frames I2-m;
• applying optical carrier modulation to each interleaved data frame I2-m, thereby providing said optical signal;
• and
• transmitting said optical signal through said optical transmission channel.

The method for receiving an optical signal from a satellite, the method being implemented by a communication station connected to an optical transmission channel, the method comprising the following steps:

• receiving said optical signal associated with a plurality of initial data frames T0-q, through said optical transmission channel;
• applying demodulation to said received optical signal, thereby providing M demodulated interleaved data frames I*2-m;
• applying a deinterleaving function to said demodulated interleaved data frames I*2-m, thereby providing a plurality of N deinterleaved data frames B*2-n;
• applying a reciprocal function of an error correction code to said deinterleaved data frames B*2-n, thereby providing a plurality of N decoded data frames B*1-n, each frame B*1-n comprising a set of digitized soft values;
• and
• applying a digitized soft value decoding function to the set of N decoded data frames B*1-n in order to determine a plurality of N regenerated data frames T*0-n, each regenerated data frame T*0-n corresponding to a reconstituted initial data frame T0-n.