Digital filter circuit having plural FIR filter circuits based on predefined filter parallelisms

A digital filter circuit, comprising:

• a digital filter input configured to receive a digital input signal set having a data parallelism;
• at least two finite impulse response (FIR) filter circuits configured to process the digital input signal set at least partially;
• and
• a connection circuit configured to selectively connect the at least two FIR filter circuits based on the data parallelism of the digital input signal set,
• wherein the at least two FIR filter circuits comprise a pre-adder sub-circuit, a convolution sub-circuit, and a post-adder sub-circuit, respectively,
• wherein the at least two FIR filter circuits have a predefined filter parallelism, respectively,
• wherein the connection circuit is configured to selectively connect the at least two FIR filter circuits based on the predefined filter parallelisms of the at least two FIR filter circuits,
• wherein the connection circuit is configured to connect the at least two FIR filter circuits if the data parallelism of the digital input signal set is bigger than the predefined filter parallelism of at least two FIR filter circuits, and wherein the connection circuit is configured to disconnect the at least two FIR filter circuits from each other if the data parallelism of the digital input signal set is smaller than or equal to the predefined filter parallelism of the at least two FIR filter circuits,
• wherein a combined structure of the pre-adder sub-circuit, of the convolution sub-circuit, and of the post-adder sub-circuit resembles a matrix decomposition or a transposed matrix decomposition,
• wherein the connection circuit is configured to selectively connect the post-adder sub-circuits of the at least two FIR filter circuits if said combined structure of the pre-adder sub-circuit, of the convolution sub-circuit, and of the post-adder sub-circuit resembles the matrix decomposition, and
• wherein the connection circuit is configured to selectively connect the pre-adder sub-circuits of the at least two FIR filter circuits if said combined structure of the pre-adder sub-circuit, of the convolution sub-circuit, and of the post-adder sub-circuit resembles the transposed matrix decomposition.