simulateSNR

R2026b

SNR for delta-sigma modulator from simulations

Since R2026a

Syntax

[snr,amp] = simulateSNR(ntf,osr,amp,f0,nlev,f,k,quadrature)

[snr,amp] = simulateSNR(ABCD,osr,amp,f0,nlev,f,k,quadrature)

Description

[snr,amp] = simulateSNR(ntf,osr,amp,f0,nlev,f,k,quadrature) simulates an delta-sigma modulator with sine wave inputs of various amplitudes specified by an ntf and calculates the signal-to-noise ratio in dB for each input.

[snr,amp] = simulateSNR(ABCD,osr,amp,f0,nlev,f,k,quadrature) calculates the SNR from inputs specified by the state-space description of the loop filter.

Input Arguments

ntf — Noise transfer function of delta-sigma modulator

object

Noise transfer function of the delta-sigma modulator in pole zero form, specified as a zpk object.

Note

Poles of NTF must match those of STF to realize STF without the addition of extra state variables.

ABCD — Loop filter of delta-sigma modulator

matrix

State space description of the loop filter of the delta-sigma modulator, specified as a matrix.

Data Types: double

osr — Oversampling ratio

real scalar

Oversampling ratio of the delta-sigma modulator, specified as a real scalar. It is the ratio of the delta-sigma modulator sampling rate to the Nyquist rate.

Data Types: double

amp — Amplitudes used to calculate SNR

row vector

Amplitudes used to calculate SNR, specified as a row vector in dB.

Data Types: double

f0 — Center frequency of binary delta-sigma modulator

real scalar

Center frequency of the binary delta-sigma modulator, specified as a real scalar.

Data Types: double

nlev — Number of levels in quantizer

real scalar | real-valued vector

Number of levels in the quantizer, specified as a real scalar for a single quantizer or real-valued vector for multiple quantizers.

f — Input signal frequency bin

real scalar

Input signal frequency adjusted to be an FFT bin, specified as a real scalar.

Data Types: double

k — Determines number of time points used for FFT

real scalar

Determines the number of time points used for FFT, specified as a real scalar. The function uses 2^k time points for FFT.

Data Types: double

quadrature — Flag to indicate is modulator is quadrature

0 | 1

A flag to indicate if the modulator being simulated is quadrature. The flag is automatically set to 1 if ntf or ABCD is complex.

Data Types: double

Output Arguments

snr — Calculated SNR values

row vector

Calculated SNR values, returned as a row vector in dB.

amp — Amplitudes used to calculate SNR

row vector

Amplitudes used to calculate SNR, returned as a row vector in dB.

Version History

Introduced in R2026a