lockin: cleanup
This commit is contained in:
parent
1e3e46242d
commit
2d43b8970b
99
Cargo.lock
generated
99
Cargo.lock
generated
@ -348,8 +348,7 @@ dependencies = [
|
||||
"criterion",
|
||||
"libm",
|
||||
"ndarray",
|
||||
"ndarray-stats",
|
||||
"rand 0.8.3",
|
||||
"rand",
|
||||
"serde",
|
||||
]
|
||||
|
||||
@ -426,17 +425,6 @@ dependencies = [
|
||||
"version_check",
|
||||
]
|
||||
|
||||
[[package]]
|
||||
name = "getrandom"
|
||||
version = "0.1.16"
|
||||
source = "registry+https://github.com/rust-lang/crates.io-index"
|
||||
checksum = "8fc3cb4d91f53b50155bdcfd23f6a4c39ae1969c2ae85982b135750cccaf5fce"
|
||||
dependencies = [
|
||||
"cfg-if 1.0.0",
|
||||
"libc",
|
||||
"wasi 0.9.0+wasi-snapshot-preview1",
|
||||
]
|
||||
|
||||
[[package]]
|
||||
name = "getrandom"
|
||||
version = "0.2.2"
|
||||
@ -445,7 +433,7 @@ checksum = "c9495705279e7140bf035dde1f6e750c162df8b625267cd52cc44e0b156732c8"
|
||||
dependencies = [
|
||||
"cfg-if 1.0.0",
|
||||
"libc",
|
||||
"wasi 0.10.2+wasi-snapshot-preview1",
|
||||
"wasi",
|
||||
]
|
||||
|
||||
[[package]]
|
||||
@ -627,30 +615,6 @@ dependencies = [
|
||||
"rawpointer",
|
||||
]
|
||||
|
||||
[[package]]
|
||||
name = "ndarray-stats"
|
||||
version = "0.4.0"
|
||||
source = "registry+https://github.com/rust-lang/crates.io-index"
|
||||
checksum = "22c95a780960082c5746f6bf0ab22d4a3b8cee72bf580acfe9f1e10bc5ea8152"
|
||||
dependencies = [
|
||||
"indexmap",
|
||||
"itertools 0.9.0",
|
||||
"ndarray",
|
||||
"noisy_float",
|
||||
"num-integer",
|
||||
"num-traits",
|
||||
"rand 0.7.3",
|
||||
]
|
||||
|
||||
[[package]]
|
||||
name = "noisy_float"
|
||||
version = "0.1.13"
|
||||
source = "registry+https://github.com/rust-lang/crates.io-index"
|
||||
checksum = "a14c16cde392a1cd18084ffd8348cb8937525130e62f0478d72dcc683698809d"
|
||||
dependencies = [
|
||||
"num-traits",
|
||||
]
|
||||
|
||||
[[package]]
|
||||
name = "num-complex"
|
||||
version = "0.3.1"
|
||||
@ -775,19 +739,6 @@ version = "0.2.2"
|
||||
source = "registry+https://github.com/rust-lang/crates.io-index"
|
||||
checksum = "e2a38df5b15c8d5c7e8654189744d8e396bddc18ad48041a500ce52d6948941f"
|
||||
|
||||
[[package]]
|
||||
name = "rand"
|
||||
version = "0.7.3"
|
||||
source = "registry+https://github.com/rust-lang/crates.io-index"
|
||||
checksum = "6a6b1679d49b24bbfe0c803429aa1874472f50d9b363131f0e89fc356b544d03"
|
||||
dependencies = [
|
||||
"getrandom 0.1.16",
|
||||
"libc",
|
||||
"rand_chacha 0.2.2",
|
||||
"rand_core 0.5.1",
|
||||
"rand_hc 0.2.0",
|
||||
]
|
||||
|
||||
[[package]]
|
||||
name = "rand"
|
||||
version = "0.8.3"
|
||||
@ -795,19 +746,9 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
|
||||
checksum = "0ef9e7e66b4468674bfcb0c81af8b7fa0bb154fa9f28eb840da5c447baeb8d7e"
|
||||
dependencies = [
|
||||
"libc",
|
||||
"rand_chacha 0.3.0",
|
||||
"rand_core 0.6.1",
|
||||
"rand_hc 0.3.0",
|
||||
]
|
||||
|
||||
[[package]]
|
||||
name = "rand_chacha"
|
||||
version = "0.2.2"
|
||||
source = "registry+https://github.com/rust-lang/crates.io-index"
|
||||
checksum = "f4c8ed856279c9737206bf725bf36935d8666ead7aa69b52be55af369d193402"
|
||||
dependencies = [
|
||||
"ppv-lite86",
|
||||
"rand_core 0.5.1",
|
||||
"rand_chacha",
|
||||
"rand_core",
|
||||
"rand_hc",
|
||||
]
|
||||
|
||||
[[package]]
|
||||
@ -817,16 +758,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
|
||||
checksum = "e12735cf05c9e10bf21534da50a147b924d555dc7a547c42e6bb2d5b6017ae0d"
|
||||
dependencies = [
|
||||
"ppv-lite86",
|
||||
"rand_core 0.6.1",
|
||||
]
|
||||
|
||||
[[package]]
|
||||
name = "rand_core"
|
||||
version = "0.5.1"
|
||||
source = "registry+https://github.com/rust-lang/crates.io-index"
|
||||
checksum = "90bde5296fc891b0cef12a6d03ddccc162ce7b2aff54160af9338f8d40df6d19"
|
||||
dependencies = [
|
||||
"getrandom 0.1.16",
|
||||
"rand_core",
|
||||
]
|
||||
|
||||
[[package]]
|
||||
@ -835,16 +767,7 @@ version = "0.6.1"
|
||||
source = "registry+https://github.com/rust-lang/crates.io-index"
|
||||
checksum = "c026d7df8b298d90ccbbc5190bd04d85e159eaf5576caeacf8741da93ccbd2e5"
|
||||
dependencies = [
|
||||
"getrandom 0.2.2",
|
||||
]
|
||||
|
||||
[[package]]
|
||||
name = "rand_hc"
|
||||
version = "0.2.0"
|
||||
source = "registry+https://github.com/rust-lang/crates.io-index"
|
||||
checksum = "ca3129af7b92a17112d59ad498c6f81eaf463253766b90396d39ea7a39d6613c"
|
||||
dependencies = [
|
||||
"rand_core 0.5.1",
|
||||
"getrandom",
|
||||
]
|
||||
|
||||
[[package]]
|
||||
@ -853,7 +776,7 @@ version = "0.3.0"
|
||||
source = "registry+https://github.com/rust-lang/crates.io-index"
|
||||
checksum = "3190ef7066a446f2e7f42e239d161e905420ccab01eb967c9eb27d21b2322a73"
|
||||
dependencies = [
|
||||
"rand_core 0.6.1",
|
||||
"rand_core",
|
||||
]
|
||||
|
||||
[[package]]
|
||||
@ -1183,12 +1106,6 @@ dependencies = [
|
||||
"winapi-util",
|
||||
]
|
||||
|
||||
[[package]]
|
||||
name = "wasi"
|
||||
version = "0.9.0+wasi-snapshot-preview1"
|
||||
source = "registry+https://github.com/rust-lang/crates.io-index"
|
||||
checksum = "cccddf32554fecc6acb585f82a32a72e28b48f8c4c1883ddfeeeaa96f7d8e519"
|
||||
|
||||
[[package]]
|
||||
name = "wasi"
|
||||
version = "0.10.2+wasi-snapshot-preview1"
|
||||
|
||||
@ -12,7 +12,6 @@ serde = { version = "1.0", features = ["derive"], default-features = false }
|
||||
criterion = "0.3"
|
||||
rand = "0.8"
|
||||
ndarray = "0.14"
|
||||
ndarray-stats = "0.4"
|
||||
|
||||
[[bench]]
|
||||
name = "micro"
|
||||
|
||||
@ -8,6 +8,7 @@ pub struct Lockin {
|
||||
}
|
||||
|
||||
impl Lockin {
|
||||
/// Create a new Lockin with given IIR coefficients.
|
||||
pub fn new(ba: &iir_int::IIRState) -> Self {
|
||||
let mut iir = iir_int::IIR::default();
|
||||
iir.ba.0.copy_from_slice(&ba.0);
|
||||
@ -17,9 +18,10 @@ impl Lockin {
|
||||
}
|
||||
}
|
||||
|
||||
pub fn update(&mut self, signal: i32, phase: i32) -> Complex<i32> {
|
||||
/// Update the lockin with a sample taken at a given phase.
|
||||
pub fn update(&mut self, sample: i32, phase: i32) -> Complex<i32> {
|
||||
// Get the LO signal for demodulation.
|
||||
let m = Complex::from_angle(phase);
|
||||
let lo = Complex::from_angle(phase);
|
||||
|
||||
// Mix with the LO signal, filter with the IIR lowpass,
|
||||
// return IQ (in-phase and quadrature) data.
|
||||
@ -27,15 +29,18 @@ impl Lockin {
|
||||
Complex(
|
||||
self.iir.update(
|
||||
&mut self.iir_state[0],
|
||||
((signal as i64 * m.0 as i64) >> 32) as _,
|
||||
((sample as i64 * lo.0 as i64) >> 32) as _,
|
||||
),
|
||||
self.iir.update(
|
||||
&mut self.iir_state[1],
|
||||
((signal as i64 * m.1 as i64) >> 32) as _,
|
||||
((sample as i64 * lo.1 as i64) >> 32) as _,
|
||||
),
|
||||
)
|
||||
}
|
||||
|
||||
/// Feed an iterator into the Lockin and return the latest I/Q data.
|
||||
/// Initial stample phase and frequency (phase increment between samples)
|
||||
/// are supplied.
|
||||
pub fn feed<I: IntoIterator<Item = i32>>(
|
||||
&mut self,
|
||||
signal: I,
|
||||
@ -46,131 +51,10 @@ impl Lockin {
|
||||
|
||||
signal
|
||||
.into_iter()
|
||||
.map(|s| {
|
||||
.map(|sample| {
|
||||
phase = phase.wrapping_add(frequency);
|
||||
self.update(s, phase)
|
||||
self.update(sample, phase)
|
||||
})
|
||||
.last()
|
||||
}
|
||||
}
|
||||
|
||||
#[cfg(test)]
|
||||
mod test {
|
||||
use crate::{
|
||||
iir_int::IIRState,
|
||||
lockin::Lockin,
|
||||
rpll::RPLL,
|
||||
testing::{isclose, max_error},
|
||||
Complex,
|
||||
};
|
||||
|
||||
use std::f64::consts::PI;
|
||||
use std::vec::Vec;
|
||||
|
||||
/// ADC full scale in machine units (16 bit signed).
|
||||
const ADC_SCALE: f64 = ((1 << 15) - 1) as _;
|
||||
|
||||
struct PllLockin {
|
||||
harmonic: i32,
|
||||
phase: i32,
|
||||
lockin: Lockin,
|
||||
}
|
||||
|
||||
impl PllLockin {
|
||||
pub fn new(harmonic: i32, phase: i32, iir: &IIRState) -> Self {
|
||||
PllLockin {
|
||||
harmonic,
|
||||
phase,
|
||||
lockin: Lockin::new(iir),
|
||||
}
|
||||
}
|
||||
|
||||
pub fn update(
|
||||
&mut self,
|
||||
input: Vec<i16>,
|
||||
phase: i32,
|
||||
frequency: i32,
|
||||
) -> Complex<i32> {
|
||||
let sample_frequency = frequency.wrapping_mul(self.harmonic);
|
||||
let mut sample_phase =
|
||||
self.phase.wrapping_add(phase.wrapping_mul(self.harmonic));
|
||||
input
|
||||
.iter()
|
||||
.map(|&s| {
|
||||
let input = (s as i32) << 16;
|
||||
let signal =
|
||||
self.lockin.update(input, sample_phase.wrapping_neg());
|
||||
sample_phase = sample_phase.wrapping_add(sample_frequency);
|
||||
signal
|
||||
})
|
||||
.last()
|
||||
.unwrap_or(Complex::default())
|
||||
}
|
||||
}
|
||||
|
||||
/// Single-frequency sinusoid.
|
||||
#[derive(Copy, Clone)]
|
||||
struct Tone {
|
||||
// Frequency (in Hz).
|
||||
frequency: f64,
|
||||
// Phase offset (in radians).
|
||||
phase: f64,
|
||||
// Amplitude in dBFS (decibels relative to full-scale).
|
||||
// A 16-bit ADC has a minimum dBFS for each sample of -90.
|
||||
amplitude_dbfs: f64,
|
||||
}
|
||||
|
||||
/// Convert dBFS to a linear ratio.
|
||||
fn linear(dbfs: f64) -> f64 {
|
||||
10f64.powf(dbfs / 20.)
|
||||
}
|
||||
|
||||
impl Tone {
|
||||
fn eval(&self, time: f64) -> f64 {
|
||||
linear(self.amplitude_dbfs)
|
||||
* (self.phase + self.frequency * time).cos()
|
||||
}
|
||||
}
|
||||
|
||||
/// Generate a full batch of samples with size `sample_buffer_size` starting at `time_offset`.
|
||||
fn sample_tones(
|
||||
tones: &Vec<Tone>,
|
||||
time_offset: f64,
|
||||
sample_buffer_size: u32,
|
||||
) -> Vec<i16> {
|
||||
(0..sample_buffer_size)
|
||||
.map(|i| {
|
||||
let time = 2. * PI * (time_offset + i as f64);
|
||||
let x: f64 = tones.iter().map(|t| t.eval(time)).sum();
|
||||
assert!(-1. < x && x < 1.);
|
||||
(x * ADC_SCALE) as i16
|
||||
})
|
||||
.collect()
|
||||
}
|
||||
|
||||
/// Total maximum noise amplitude of the input signal after 2nd order lowpass filter.
|
||||
/// Constructive interference is assumed.
|
||||
///
|
||||
/// # Args
|
||||
/// * `tones` - Noise sources at the ADC input.
|
||||
/// * `frequency` - Frequency of the signal of interest.
|
||||
/// * `corner` - Low-pass filter 3dB corner cutoff frequency.
|
||||
///
|
||||
/// # Returns
|
||||
/// Upper bound of the total amplitude of all noise sources in linear units full scale.
|
||||
fn sampled_noise_amplitude(
|
||||
tones: &Vec<Tone>,
|
||||
frequency: f64,
|
||||
corner: f64,
|
||||
) -> f64 {
|
||||
tones
|
||||
.iter()
|
||||
.map(|t| {
|
||||
let df = (t.frequency - frequency) / corner;
|
||||
// Assuming a 2nd order lowpass filter: 40dB/decade.
|
||||
linear(t.amplitude_dbfs - 40. * df.abs().max(1.).log10())
|
||||
})
|
||||
.sum::<f64>()
|
||||
.max(1. / ADC_SCALE / 2.) // 1/2 LSB from quantization
|
||||
}
|
||||
}
|
||||
|
||||
@ -84,7 +84,6 @@ impl RPLL {
|
||||
mod test {
|
||||
use super::RPLL;
|
||||
use ndarray::prelude::*;
|
||||
use ndarray_stats::QuantileExt;
|
||||
use rand::{prelude::*, rngs::StdRng};
|
||||
use std::vec::Vec;
|
||||
|
||||
@ -254,7 +253,7 @@ mod test {
|
||||
h.shift_frequency = 10;
|
||||
h.shift_phase = 9;
|
||||
|
||||
h.measure(1 << 16, [5e-7, 3e-2, 3e-2, 2e-2]);
|
||||
h.measure(1 << 16, [5e-7, 3e-2, 2e-5, 2e-2]);
|
||||
}
|
||||
|
||||
#[test]
|
||||
|
||||
Loading…
Reference in New Issue
Block a user