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: n : int
the number of optimized zeros to return
opt : int, optional
flag for optimized zeros, defaults to 1 0 -> not optimized 1 -> optimized 2 -> optimized with at least one zero at band-center
Returns: zeros : ndarray 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 [R7]
[R7] Richard Schreier, Gabor C. Temes, “Understanding Delta-Sigma Data Converters,” IEEE Press and Wiley Interscience, 2005.