Method for transmitting a multi-carrier signal, a receiving method, devices, and associated computer programs

A device for transmitting a multicarrier signal implementing an Offset Quadrature Amplitude Modulation (OQAM)-type modulation intended for transmission via a channel transmission system, formed by a temporal succession of symbols comprising a set of data elements comprising:

• real-value informative elements of data, and
• for at least some of said symbols, elements of reference data, so-called pilots, known by at least one receiver designed for receiving the multi-carrier signal,
• as each of said data elements modulates a carrier frequency of said signal, a carrier frequency modulated by one of said data elements being called a carrier,
• wherein the device comprises:
• a transmitter unit, wherein a set of carriers is allocated to the transmitter unit, and
• an insertion unit, which inserts a sequence of pilots specific to said transmitter unit at a given time (TS) into the multi-carrier signal on said allocated set of carriers, said sequence of pilots comprising:
• a sequence of non-zero complex values, inserted on odd or even carriers, alternating with zero values, inserted on the other carriers, respectively even or odd-numbered,
• non-zero complex values of the sequence of pilots, their frequency transforms and inverse frequency transforms being with a constant envelope, and
• a sequence of zero values modulating the carriers of the set of carriers allocated at the following time (TS+τ0).

A method for receiving a signal corresponding to at least one multi-carrier signal implementing an Offset Quadrature Amplitude Modulation (OQAM)-type modulation, transmitted by at least one transmitter unit via a transmission channel, said signal being formed of a temporal succession of symbols comprising a set of data elements comprising:

• real-value informative elements of data, and
• for at least some of said symbols, elements of reference data, so-called pilots, known by at least one receiver designed for receiving the multi-carrier signal,
• as each of said data elements modulates a carrier frequency of said signal, a carrier frequency modulated by one of said data elements being called a carrier,
• a set of carriers being allocated to a transmitter unit,
• wherein, a sequence of pilots specific to said transmitter unit having been. inserted into the multi-carrier signal on said allocated set of carriers, said sequence of pilots comprising:
• a sequence of non-zero complex values, inserted on odd or even carriers, alternating with zero values, inserted on the other carriers, respectively even or odd-numbered, at a given time (TS),
• non-zero complex values of the sequence of pilots, their frequency transforms and inverse frequency transforms being with a constant envelope, and
• a sequence of zero values modulating the carriers of the set of carriers allocated at the following time (TS+τ0),
• wherein the receiving method comprises the following acts performed by a receiving device:
• receiving the multi-carrier signal from the transmission channel;
• extracting complex values corresponding to non-zero values of the sequence of pilots on the odd or even carriers, after passing through the transmission channel,
• estimating a frequency response of said transmission channel on the odd or even carriers from the complex values extracted, and
• estimating a frequency response of said transmission channel on the other carriers, respectively even or odd by frequency interpolation of the channel response, estimated on the even or odd carriers.

A device for receiving a signal corresponding to at least one multi-carrier signal implementing an Offset Quadrature Amplitude Modulation (OQAM)-type modulation, transmitted by at least one transmitter unit via a transmission channel, said signal being formed of a temporal succession of symbols comprising a set of data elements comprising:

• real-value informative elements of data, and
• for at least some of said symbols, elements of reference data, so-called pilots, known by at least one receiver designed for receiving the multi-carrier signal,
• as each of said data elements modulates a carrier frequency of said signal, a carrier frequency modulated by one of said data elements being called a carrier,
• a set of carriers being allocated to said transmitter unit,
• wherein, a sequence of pilots specific to said transmitter unit having been inserted at a given time into the multi-carrier signal on said allocated set of carriers, said sequence of pilots comprising:
• a sequence of non-zero complex values, inserted on odd or even carriers, alternating with zero values, inserted on the other carriers,
• non-zero complex values of the sequence of pilots, their frequency transforms and inverse frequency transforms being with a constant envelope, and
• a sequence of zero values modulating the carriers of the set of carriers allocated at a following time (TS+τ0),
• wherein said receiving device comprises the following units:
• a unit which extracts complex values corresponding to non-zero values of the sequence of pilots on the odd or even carriers, after passing through the transmission channel,
• a unit which estimates a frequency response of said transmission channel on the odd or even carriers from the complex values extracted, and
• a unit which estimates a frequency response of said transmission channel on the other carriers, respectively even or odd by frequency interpolation of the channel response, estimated on the even or odd carriers.

A non-transitory computer-readable medium comprising program code instructions stored thereon for implementing a method of transmitting a multi-carrier signal when the instructions are executed by a processor of a transmission device, the multi-carrier signal implementing an Offset Quadrature Amplitude Modulation (OQAM)-type modulation intended for transmission via a channel transmission system, formed by a temporal succession of symbols comprising a set of data elements comprising:

• real-value informative elements of data, and
• for at least some of said symbols, elements of reference data, so-called pilots, known by at least one receiver designed for receiving the multi-carrier signal,
• as each of said data elements modulates a carrier frequency of said signal, a carrier frequency modulated by one of said data elements being called a carrier,
• a set of carriers being allocated to a transmitter unit,
• wherein said instructions configure the transmission device to perform acts comprising:
• inserting a sequence of pilots specific to said transmitter unit at a given time (TS) into the multi-carrier signal on said allocated set of carriers,
• said sequence of pilots comprising:
• a sequence of non-zero complex values, inserted on odd or even carriers, alternating with zero values, inserted on the other carriers, respectively even or odd numbered,
• non-zero complex values of the sequence of pilots, their frequency transforms and inverse frequency transforms being with a constant envelope, and
• a sequence of zero values modulating the carriers of the set of carriers allocated at a following time (TS+τ0);
• and
• transmitting the multi-carrier signal to the channel transmission system.

A non-transitory computer-readable medium comprising program code instructions stored thereon for implementing a method of receiving a signal when the instructions are executed by a processor of a receiving device, the signal corresponding to at least one multi-carrier signal implementing an Offset Quadrature Amplitude Modulation (OQAM)-type modulation, transmitted by at least one transmitter unit via a transmission channel, said signal being formed of a temporal succession of symbols comprising a set of data elements comprising:

• real-value informative elements of data, and
• for at least some of said symbols, elements of reference data, so-called pilots, known by at least one receiver designed for receiving the multi-carrier signal,
• as each of said data elements modulates a carrier frequency of said signal, a carrier frequency modulated by one of said data elements being called a carrier,
• a set of carriers being allocated to a transmitter unit,
• wherein, a sequence of pilots specific to said transmitter unit having been inserted into the multi-carrier signal on said allocated set of carriers, said sequence of pilots comprising:
• a sequence of non-zero complex values, inserted on odd or even carriers, alternating with zero values, inserted on the other carriers, respectively even or odd-numbered, at a given time (TS),
• non-zero complex values of the sequence of pilots, their frequency transforms and inverse frequency transforms being with a constant envelope, and
• a sequence of zero values modulating the carriers of the set of carriers allocated at a following time (TS+τ0),
• wherein the instructions configure the receiving device to perform acts comprising:
• receiving the multi-carrier signal from the transmission channel;
• extracting complex values corresponding to non-zero values of the sequence of pilots on the odd or even carriers, after passing through the transmission channel,
• estimating a frequency response of said transmission channel on the odd or even carriers from the complex values extracted,
• estimating a frequency response of said transmission channel on the other carriers, respectively even or odd by frequency interpolation of the channel response, estimated on the even or odd carriers.