Transmitter, transmission method and receiver
First Claim
1. Method for simultaneous transmission of modulated waves using a plurality of orthogonal frequencies, in which symbols are transmitted for a period T+Δ
- T, two transmission frequencies being separated by 1/T, T being the useful transmission interval and Δ
T being the transition interval, absorbing the non-stationarities due to the arrival of echoes, in which during each transmission interval of period T+Δ
T a (real part, imaginary part) or (amplitude, phase) pair is transmitted on each frequency, the (real part, imaginary part) or (amplitude, phase) pair being in one-to-one equivalence with information to be transmitted, characterised in that the number of pairs possible is greater than 4, in that the symbols transmitted are constituted periodically by reference signals enabling, at a receiving end, equalization of the transmission channel, and in that synchronisation signals are transmitted enabling, at the receiving end, processing of the signal during the useful transmission intervals of period T so as to recover tie orthogonality of the channels corresponding to the orthogonal frequencies.
6 Assignments
0 Petitions
Accused Products
Abstract
A transmission method and a transmitter and receiver Structure is disclosed which provides for transmission of modulated waves using long pulses with a plurality of frequencies. The method involves two consecutive frequencies being separated by 1/T, where T is the period of the useful transmission intervals. The method and the apparatus are particularly suited to broadcasting and reception of television and radio signals as well as telephone communications between exchanges and between radio telephones and communication stations including terrestrial stations and satellites and local computer networks. Most particularly the method is applicable to high fidelity radio transmissions as well as to high definition television (HDTV).
169 Citations
19 Claims
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1. Method for simultaneous transmission of modulated waves using a plurality of orthogonal frequencies, in which symbols are transmitted for a period T+Δ
- T, two transmission frequencies being separated by 1/T, T being the useful transmission interval and Δ
T being the transition interval, absorbing the non-stationarities due to the arrival of echoes, in which during each transmission interval of period T+Δ
T a (real part, imaginary part) or (amplitude, phase) pair is transmitted on each frequency, the (real part, imaginary part) or (amplitude, phase) pair being in one-to-one equivalence with information to be transmitted, characterised in that the number of pairs possible is greater than 4, in that the symbols transmitted are constituted periodically by reference signals enabling, at a receiving end, equalization of the transmission channel, and in that synchronisation signals are transmitted enabling, at the receiving end, processing of the signal during the useful transmission intervals of period T so as to recover tie orthogonality of the channels corresponding to the orthogonal frequencies. - View Dependent Claims (2, 3, 4, 5, 6)
- T, two transmission frequencies being separated by 1/T, T being the useful transmission interval and Δ
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7. A transmitter system for simultaneous transmission of modulating wave using a plurality of orthogonal frequencies in which symbols are transmitted for a period T+Δ
- T, two transmission frequencies being separated by 1/T, T being the useful transmission interval and Δ
T being the transition interval and in which during each transmission interval of period T+Δ
T a real part-imaginary part pair or amplitude-phase pair is transmitted on each frequency, the real part-imaginary part pair or amplitude-phase pair being in one-to-one equivalence with the information to be transmitted said system comprising;a coding device for receiving said information to be transmitted, said coding device including a shaping means to produce a desired shape of signals and a digital conversion means receiving the output of said shaping device and providing said real part-imaginary part pair or amplitude-phase pair; and a modulation device for enabling the transmission, during a useful transmission interval of said period T+Δ
T for each frequency used, of either a symbol chosen from a large plurality of amplitude, phase pairs, or a reference signal to ensure equalization of the transmission channel. - View Dependent Claims (8, 9, 10, 11)
- T, two transmission frequencies being separated by 1/T, T being the useful transmission interval and Δ
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12. A receiver system for receiving modulated waves transmitted with a plurality of orthogonal frequencies, in which symbols are transmitted for a period T+Δ
- T, two transmission frequencies being separated by 1/T, T being the useful transmission interval and Δ
T being the transmission interval in which, during each transition interval of said period, a real part-imaginary part pair or amplitude-phase pair is transmitted on each frequency, the real part-imaginary part pair or amplitude-phase pair being in one-to-one equivalence with information to be transmitted, said receiver system comprising;means for transposing and sampling which means are synchronous with a signal and wherein said means for transposing and sampling include a means for demodulation of a modulated wave transmission using symbols transmitted during said period T+Δ
T on said plurality of orthogonal frequencies, said means for transposing and sampling further including a servocontrol device ensuring the synchronization of the receiver system with a receive signal using said transition interval Δ
T, said means for transposing and sampling further including a test means using reference signals for equalizing transmission channels. - View Dependent Claims (13, 14, 15, 16, 17, 18, 19)
- T, two transmission frequencies being separated by 1/T, T being the useful transmission interval and Δ
Specification