Digital filtering by polyphase network:Application to sample-rate alteration and filter banks 论文

详细信息

发表期刊/会议

IEEE Transactions on Acoustics Speech and Signal Processing

发表日期

1976-04-01

发表年份

1976

摘要

The digital filtering process can be achieved by a set of phase shifters with suitable characteristics. A particular set, named polyphase network, is defined and analyzed. It permits the use of recursive devices for efficient sample-rate alteration. The comparison with conventional filters shows that, with the same active memory, a reduction of computation rate approaching a factor of 2 can be achieved when the alteration factor increases. A more substantial gain can be obtained in the direct realization of a uniform bank of recursive filters through combination of the polyphase network with a discrete Fourier transform (DFT) computer; savings in hardware also result from the low sensitivity of the structure to coefficient word lengths.