Filtering of subtractive discrete dither in quantizers: Some new results

Subtractive dither in quantizers is examined as a means to mitigate quantizer non-linearity. The effects of filtering the dither signal to shape its spectral content outside the signal band while maintaining its benefits are studied in detail. Design strategies for finite impulse response (FIR) filters that accomplish spectral shaping as well as allay quantizer non-linearity are derived theoretically. Simulation results for low/medium resolution quantizers are presented to validate the derived conditions on the filter structures.