Struct idsp::Dsm

pub struct Dsm<const K: usize> { /* private fields */ }

Delta-sigma modulator

• MASH-(1)^K architecture
• 0 <= K <= 8 (K=0 is valid but the output will be the constant quantized 0)
• The output range is 1 - (1 << K - 1)..=(1 << K - 1).
• Given constant input x0, the average output is x0/(1 << 32).
• The noise goes up as K * 20 dB/decade.

let mut d = Dsm::<3>::default();
let x = 0x87654321;
let n = 1 << 20;
let y = (0..n).map(|_| d.update(x) as f32).sum::<f32>() / n as f32;
let m = x as f32 / (1u64 << 32) as f32;
assert!((y / m - 1.0).abs() < (1.0 / n as f32).sqrt(), "{y} != {m}");

Implementations

impl<const K: usize> Dsm<K>

pub fn update(&mut self, x: u32) -> i8

Ingest input sample, emit new output.

Arguments

• x: New input sample

Returns

New output

Trait Implementations

impl<const K: usize> Clone for Dsm<K>

fn clone(&self) -> Dsm<K>

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl<const K: usize> Debug for Dsm<K>

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl<const K: usize> Default for Dsm<K>

fn default() -> Self

Returns the “default value” for a type.

impl<const K: usize> PartialEq for Dsm<K>

fn eq(&self, other: &Dsm<K>) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl<const K: usize> PartialOrd for Dsm<K>

fn partial_cmp(&self, other: &Dsm<K>) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

fn lt(&self, other: &Rhs) -> bool

Tests less than (for self and other) and is used by the < operator.

fn le(&self, other: &Rhs) -> bool

Tests less than or equal to (for self and other) and is used by the <= operator.

fn gt(&self, other: &Rhs) -> bool

Tests greater than (for self and other) and is used by the > operator.

fn ge(&self, other: &Rhs) -> bool

Tests greater than or equal to (for self and other) and is used by the >= operator.

impl<const K: usize> Copy for Dsm<K>

impl<const K: usize> Eq for Dsm<K>

impl<const K: usize> StructuralPartialEq for Dsm<K>