pydsm.delsig.ds_optzeros

pydsm.delsig.ds_optzeros(n, opt=1)

Zeros which minimize the in-band noise of a delta-sigma modulator

Helper function for synthesizeNTF, that returns the zeros as normalized angular frequencies

Parameters

nint

the number of optimized zeros to return

optint, optional

flag for optimized zeros, defaults to 1 0 -> not optimized 1 -> optimized 2 -> optimized with at least one zero at band-center

Returns

zerosndarray of reals

the zeros for the modulator as normalized angular frequencies.

Notes

The zeros are always located on the complex unit circle. As such, they are returned as frequencies, not as complex values.

The zero’s frequencies are normalized with respect to the signal bandwidth. See also Sec. 4.3.1 in [1]

1

Richard Schreier, Gabor C. Temes, “Understanding Delta-Sigma Data Converters,” IEEE Press and Wiley Interscience, 2005.