Efficient Halfband FIR Filter Structures for RF and IF Data Converters

Halfband filters used in multi-gigasample-per-second radio frequency/intermediate frequency data converters to interpolate or decimate the signal are responsible for a considerable portion of the power consumption. We now know that the sensitivity of halfband filters to coefficient quantization can be systematically reduced. This can be exploited in the filter-design process to yield halfband filters with reduced hardware complexity, leading to lower power consumption and/or higher operating speeds. The general derivation of such desensitized halfband structures and the relationship between their coefficients and those of conventional halfband filters are presented. Cadence implementation results show significant improvements.