OFDM modulator for block-filtered OFDM transmitter, related block-filtered OFDM transmitter and transceiver system

A block-filtered OFDM transmitter configured to communicate using a variable transmission hand and a numbering that is variable in real time, the OFDM transmitter comprising:

• a serial-to-parallel conversion module configured to convert an incoming serial data stream into NFFT parallel data carriers,
• a set of M OFDM modulators, each OFDM modulator being associated with an index i such that 0≤i≤M−1, M being constant regardless of the numbering and the variable transmission band of the block-filtered OFDM transmitter, each OFDM modulator being configured to receive as input a block of Nc consecutive data carriers of said NFFT parallel data carriers, the blocks of Nc consecutive carriers being processed by each modulator being all disjoint, NFFT being equal to M times Nc, and
• a polyphase filter bank configured to be connected to M outputs of said set of M OFDM modulators, wherein each OFDM modulator further comprises:
• a transformation module configured to apply a discrete inverse Fourier transform IDFT of constant size NIDFT independently of the numbering and the transmission band of the block-filtered OFDM transmitter,
• a filling module, an input of which is connected to an output of the predistortion module, and an output of which is connected to an input of the transformation module, the filling module being configured to insert (NIDFT−Nc) null carriers in succession to the Nc consecutive data carriers independently of a parity of an index i associated with said OFDM modulator, and
• a decimation module, located downstream of the transformation module, the decimation module being configured to decimate time samples obtained from the transformation module by a factor equal to NIDFT/(2Nc).

An OFDM modulator of a set of M OFDM modulators in parallel with a block-filtered OFDM transmitter configured to communicate using a transmission band and a numbering that is variable in real time,

• each OFDM modulator of the set of M OFDM modulators being associated with an index i such that 0≤i≤M−1, M being constant, independently of the numbering and the transmission band of the block-filtered OFDM transmitter,
• the block-filtered OFDM transmitter further comprising a serial-to-parallel conversion module, upstream of the set of M OFDM modulators, configured to convert an incoming serial data stream into NFFT parallel data carriers,
• the OFDM modulator being configured to receive a block of Nc consecutive data carriers of the NFFT parallel data carriers as input,
• the OFDM modulator comprising at least one predistortion module configured to receive the Nc consecutive data carriers and configured to compensate for distortion subsequently introduced by a polyphase filter bank of the block-filtered OFDM transmitter, an output of the OFDM modulator being connectable to an input of the polyphase filter bank,
• wherein the OFDM modulator further comprises:
• a transformation module configured to apply a discrete inverse Fourier transform IDFT of constant size NIDFT independently of the numbering and the transmission band of the block-filtered OFDM transmitter,
• a filling module, an input of which is connected to an output of the predistortion module, and an output of which is connected to an input of the transformation module, the filling module being configured to insert (NIDFT−Nc) null carriers in succession to the Nc consecutive data carriers independently of a parity of an index i associated with the OFDM modulator, and
• a spectrum shifting module configured to apply, to samples, in the order of arrival, a rotation in a time domain of a value of (−1)i+1π/2, where i is the index associated with the OFDM modulator.