Signal processing device, signal processing method, and signal level display device

A signal processing method, comprising the steps of:

• previously generating a look-up table storage unit that represents a relationship between parallel bit patterns prepared by aligning sequentially received input 1-bit digital signals in chronological order and resulting values of a filtering arithmetic operation on the basis of said bit patterns;
• receiving input 1-bit digital signals generated by ΔΣ modification;
• aligning bits of said input 1-bit digital signals in a chronological order to output parallel bit pattern;
• indexing said bit patterns output from said bit-pattern output unit;
• and using said indexes to output the resulting values of said filtering arithmetic operation corresponding to sad bit patterns listed in said look-up table stored in said look-up table storage unit.

A signal level display device comprising:

• a bit-pattern output unit for receiving input 1-bit digital signals generated by ΔΣ modification and aligning bits of said input 1-bit digital signals in a chronological order to output parallel bit pattern;
• a look-up table storage unit for storing a look-up table that represents a relationship between said bit patterns output from said bit pattern output unit and resulting values of a filtering arithmetic operation on the basis of said bit patterns;
• a signal level generator for using said bit patterns output from said bit-pattern output unit as indexes to output the resulting values of said filtering arithmetic operation corresponding to said bit patterns listed in said look-up table stored in said look-up table storage unit;
• and a signal level display unit for displaying a signal level based on said resulting values of said filtering arithmetic operation output from said signal level generator.