Filter circuits and associated signal processing methods

A filter circuit, comprising:

• a plurality of registers, each being configured to store an input;
• a switch circuit, configured to adjust arrangement of a series of coefficients according to a count value to generate a series of rearranged coefficients, wherein the count value is accumulated in response to reception of a new input of the filter circuit;
• a plurality of multipliers, coupled to the switch circuit and the registers and configured to receive the inputs from the registers and receive the series of rearranged coefficients from the switch circuit, wherein each multiplier is configured to generate a multiplication result according to the received input and the received coefficient;
• and
• a summation circuit, coupled to the multipliers and configured to sum up the multiplication results to generate an output;
• wherein when the filter circuit receives the new input, the new input is written in one of the registers to replace the oldest input among the inputs currently being stored in the registers.

A signal processing method, for generating at least one output according to a plurality of inputs and a plurality of coefficients, comprising:

• obtaining a series of inputs and a series of coefficients, wherein the series of inputs comprises the plurality of inputs and the series of coefficients comprises the plurality of coefficients;
• adjusting arrangement of the series of inputs or the series of coefficients according to a count value to generate a series of rearranged inputs or a series of rearranged coefficients;
• sequentially multiplying the inputs comprised in the series of rearranged inputs by the coefficients comprised in the series of coefficients or sequentially multiplying the inputs comprised in the series of inputs by the coefficients comprised in the series of rearranged coefficients to generate a plurality of multiplication results;
• summing up the multiplication results to generate the at least one output;
• and
• storing the inputs in a plurality of registers of a filter circuit;
• wherein when the filter circuit receives a new input, the new input is written in the register which stores the oldest input among the inputs currently stored in the registers to replace the oldest input.