An OFDM modulator (28 0, 28 1,..., 28 i,..., 28 M-1) of a set of M OFDM modulators in parallel with a block filtered OFDM transmitter suitable for communication using a transmission band and a numbering, variable in real time, each OFDM modulator being associated with an index i such that 0 ≤ i ≤ M - 1, M being constant independently of the numbering and transmission band of said transmitter, the block-filtered OFDM transmitter further comprising a serial-to-parallel conversion module upstream of said assembly, configured to convert an incoming serial data stream into N FFT parallel data carriers, the OFDM modulator (28 0, 28 1,..., 28 i,..., 28 M-1) being configured to receive a block of N c consecutive data carriers of said N FFT parallel data carriers as input, the OFDM modulator (28 0, 28 1,..., 28 i,..., 28 M-1) comprising at least one predistortion module configured to receive said N c consecutive data carriers and configured to compensate for distortion subsequently introduced by a polyphase filter bank of said OFDM transmitter, the output of said OFDM modulator being connectable to the input of the polyphase filter bank characterized in that the OFDM modulator (28 0, 28 1,..., 28 i,..., 28 M-1) further comprises: - a transformation module configured to apply a discrete inverse Fourier transform IDFT of constant size N IDFT independently of the numbering and transmission band of said transmitter, - a filling module the input of which is connected to the output of the predistortion module, and the output of which is connected to the input of the transformation module, the filling module being configured to insert ( N IDFT - N c) null carriers in succession to the N c consecutive data carriers independently of the parity of the index i associated with said OFDM modulator each OFDM modulator being associated with an index i such that 0 ≤ i ≤ M - 1, M being constant independently of the numbering and transmission band of said transmitter, the block-filtered OFDM transmitter further comprising a serial-to-parallel conversion module upstream of said assembly, configured to convert an incoming serial data stream into N FFT parallel data carriers, the OFDM modulator (28 0, 28 1,..., 28 i,..., 28 M-1) being configured to receive a block of N c consecutive data carriers of said N FFT parallel data carriers as input, the OFDM modulator (28 0, 28 1,..., 28 i,..., 28 M-1) comprising at least one predistortion module configured to receive said N c consecutive data carriers and configured to compensate for distortion subsequently introduced by a polyphase filter bank of said OFDM transmitter, the output of said OFDM modulator being connectable to the input of the polyphase filter bank characterized in that the OFDM modulator (28 0, 28 1,..., 28 i,..., 28 M-1) further comprises: - a transformation module configured to apply a discrete inverse Fourier transform IDFT of constant size N IDFT independently of the numbering and transmission band of said transmitter, - a filling module the input of which is connected to the output of the predistortion module, and the output of which is connected to the input of the transformation module, the filling module being configured to insert ( N IDFT - N c) null carriers in succession to the N c consecutive data carriers independently of the parity of the index i associated with said OFDM modulator - a transformation module configured to apply a discrete inverse Fourier transform IDFT of constant size N IDFT independently of the numbering and transmission band of said transmitter, - a filling module the input of which is connected to the output of the predistortion module, and the output of which is connected to the input of the transformation module, the filling module being configured to insert ( N IDFT - N c) null carriers in succession to the N c consecutive data carriers independently of the parity of the index i associated with said OFDM modulator