Trait ModulationParams 

pub trait ModulationParams:
    Copy
    + Default
    + 'static {
    const NTONES: u32;
    const BITS_PER_SYMBOL: u32;
    const NSPS: u32;
    const SYMBOL_DT: f32;
    const TONE_SPACING_HZ: f32;
    const GRAY_MAP: &'static [u8];
    const GFSK_BT: f32;
    const GFSK_HMOD: f32;
    const NFFT_PER_SYMBOL_FACTOR: u32;
    const NSTEP_PER_SYMBOL: u32;
    const NDOWN: u32;
    const LLR_SCALE: f32 = 2.83;
}

Baseband modulation parameters (tones, symbol rate, Gray mapping, Gaussian shaping and the tunable DSP ratios the pipeline reads per protocol).

All constants are evaluated at compile time; the trait carries no data so implementors are typically zero-sized types.

Required Associated Constants

const NTONES: u32

Number of FSK tones (M in M-ary FSK).

const BITS_PER_SYMBOL: u32

Information bits carried per modulated symbol (= log2(NTONES)).

const NSPS: u32

Samples per symbol at the 12 kHz pipeline sample rate.

const SYMBOL_DT: f32

Symbol duration in seconds (= NSPS / 12000).

const TONE_SPACING_HZ: f32

Spacing between adjacent tones, in Hz.

const GRAY_MAP: &'static [u8]

Gray-code map: GRAY_MAP[tone_index] returns the NATURAL-bit pattern for that tone. The map covers at least the data alphabet (2^BITS_PER_SYMBOL entries) and at most the full tone set (NTONES entries). Protocols whose sync tones are part of the data alphabet (FT8 / FT4 / FST4 / WSPR) have len() == NTONES == 2^BITS_PER_SYMBOL; protocols that reserve additional sync-only tones (JT9, JT65, Q65) either trim the map to the data alphabet (JT9: 8 entries for 9 tones) or extend it with identity over the sync slots (JT65 / Q65). Pinned by tests/protocol_invariants.rs.

const GFSK_BT: f32

Gaussian bandwidth-time product. FT8 = 2.0, FT4 = 1.0, FST4 ≈ 1.0.

const GFSK_HMOD: f32

Modulation index h — the phase increment per symbol is 2π · h. FT8 and FT4 both use 1.0 (orthogonal tones at 1/T spacing).

const NFFT_PER_SYMBOL_FACTOR: u32

Per-symbol FFT size = NSPS * NFFT_PER_SYMBOL_FACTOR. FT8 = 2 (window is 2·NSPS), FT4 = 4 (window is 4·NSPS) — trade-off between frequency resolution and time localisation.

const NSTEP_PER_SYMBOL: u32

Coarse-sync time-step = NSPS / NSTEP_PER_SYMBOL. FT8 = 4 (quarter-symbol resolution), FT4 = 1 (symbol-granular).

const NDOWN: u32

Downsample decimation factor: baseband rate = 12 000 / NDOWN Hz. FT8 = 60 (→200 Hz), FT4 = 18 (→667 Hz). Proportional to tone spacing.

Provided Associated Constants

const LLR_SCALE: f32 = 2.83

LLR scale factor applied after standard-deviation normalisation. FT8 uses 2.83 (empirical, from WSJT-X ft8b.f90). Different bits-per-symbol counts may shift the optimum — FT4’s 2-bit LLR dynamics are not identical to FT8’s 3-bit case.

Dyn Compatibility

This trait is not dyn compatible.

In older versions of Rust, dyn compatibility was called "object safety", so this trait is not object safe.

Implementors

impl ModulationParams for Fst4s60

const NTONES: u32 = 4

const BITS_PER_SYMBOL: u32 = 2

const NSPS: u32 = 3_840

const SYMBOL_DT: f32 = 0.32

const TONE_SPACING_HZ: f32 = 3.125

const GRAY_MAP: &'static [u8]

const GFSK_BT: f32 = 1.0

const GFSK_HMOD: f32 = 1.0

const NFFT_PER_SYMBOL_FACTOR: u32 = 2

const NSTEP_PER_SYMBOL: u32 = 2

const NDOWN: u32 = 192

impl ModulationParams for Ft4

const NTONES: u32 = 4

const BITS_PER_SYMBOL: u32 = 2

const NSPS: u32 = 576

const SYMBOL_DT: f32 = 0.048

const TONE_SPACING_HZ: f32 = 20.833

const GRAY_MAP: &'static [u8]

const GFSK_BT: f32 = 1.0

const GFSK_HMOD: f32 = 1.0

const NFFT_PER_SYMBOL_FACTOR: u32 = 4

const NSTEP_PER_SYMBOL: u32 = 2

const NDOWN: u32 = 18

impl ModulationParams for Ft8

const NTONES: u32

const BITS_PER_SYMBOL: u32 = 3

const NSPS: u32

const SYMBOL_DT: f32 = params::SYMBOL_DT

const TONE_SPACING_HZ: f32 = 6.25

const GRAY_MAP: &'static [u8]

const GFSK_BT: f32 = 2.0

const GFSK_HMOD: f32 = 1.0

const NFFT_PER_SYMBOL_FACTOR: u32 = 2

const NSTEP_PER_SYMBOL: u32 = 4

const NDOWN: u32 = 60

impl ModulationParams for Jt9

const NTONES: u32 = 9

const BITS_PER_SYMBOL: u32 = 3

const NSPS: u32 = 6912

const SYMBOL_DT: f32

const TONE_SPACING_HZ: f32

const GRAY_MAP: &'static [u8]

const GFSK_BT: f32 = 0.0

const GFSK_HMOD: f32 = 1.0

const NFFT_PER_SYMBOL_FACTOR: u32 = 2

const NSTEP_PER_SYMBOL: u32 = 2

const NDOWN: u32 = 8

impl ModulationParams for Jt65

const NTONES: u32 = 66

const BITS_PER_SYMBOL: u32 = 6

const NSPS: u32 = 4460

const SYMBOL_DT: f32

const TONE_SPACING_HZ: f32

const GRAY_MAP: &'static [u8]

const GFSK_BT: f32 = 0.0

const GFSK_HMOD: f32 = 1.0

const NFFT_PER_SYMBOL_FACTOR: u32 = 2

const NSTEP_PER_SYMBOL: u32 = 2

const NDOWN: u32 = 4

impl ModulationParams for Q65a30

const NTONES: u32 = 65

const BITS_PER_SYMBOL: u32 = 6

const NSPS: u32 = 3600

const SYMBOL_DT: f32

const TONE_SPACING_HZ: f32

const GRAY_MAP: &'static [u8]

const GFSK_BT: f32 = 0.0

const GFSK_HMOD: f32 = 1.0

const NFFT_PER_SYMBOL_FACTOR: u32 = 2

const NSTEP_PER_SYMBOL: u32 = 2

const NDOWN: u32 = 3

impl ModulationParams for Q65a60

const NTONES: u32 = 65

const BITS_PER_SYMBOL: u32 = 6

const NSPS: u32 = 7200

const SYMBOL_DT: f32

const TONE_SPACING_HZ: f32

const GRAY_MAP: &'static [u8]

const GFSK_BT: f32 = 0.0

const GFSK_HMOD: f32 = 1.0

const NFFT_PER_SYMBOL_FACTOR: u32 = 2

const NSTEP_PER_SYMBOL: u32 = 2

const NDOWN: u32 = 3

impl ModulationParams for Q65b60

const NTONES: u32 = 65

const BITS_PER_SYMBOL: u32 = 6

const NSPS: u32 = 7200

const SYMBOL_DT: f32

const TONE_SPACING_HZ: f32

const GRAY_MAP: &'static [u8]

const GFSK_BT: f32 = 0.0

const GFSK_HMOD: f32 = 1.0

const NFFT_PER_SYMBOL_FACTOR: u32 = 2

const NSTEP_PER_SYMBOL: u32 = 2

const NDOWN: u32 = 3

impl ModulationParams for Q65c60

const NTONES: u32 = 65

const BITS_PER_SYMBOL: u32 = 6

const NSPS: u32 = 7200

const SYMBOL_DT: f32

const TONE_SPACING_HZ: f32

const GRAY_MAP: &'static [u8]

const GFSK_BT: f32 = 0.0

const GFSK_HMOD: f32 = 1.0

const NFFT_PER_SYMBOL_FACTOR: u32 = 2

const NSTEP_PER_SYMBOL: u32 = 2

const NDOWN: u32 = 3

impl ModulationParams for Q65d60

const NTONES: u32 = 65

const BITS_PER_SYMBOL: u32 = 6

const NSPS: u32 = 7200

const SYMBOL_DT: f32

const TONE_SPACING_HZ: f32

const GRAY_MAP: &'static [u8]

const GFSK_BT: f32 = 0.0

const GFSK_HMOD: f32 = 1.0

const NFFT_PER_SYMBOL_FACTOR: u32 = 2

const NSTEP_PER_SYMBOL: u32 = 2

const NDOWN: u32 = 3

impl ModulationParams for Q65e60

const NTONES: u32 = 65

const BITS_PER_SYMBOL: u32 = 6

const NSPS: u32 = 7200

const SYMBOL_DT: f32

const TONE_SPACING_HZ: f32

const GRAY_MAP: &'static [u8]

const GFSK_BT: f32 = 0.0

const GFSK_HMOD: f32 = 1.0

const NFFT_PER_SYMBOL_FACTOR: u32 = 2

const NSTEP_PER_SYMBOL: u32 = 2

const NDOWN: u32 = 3

impl ModulationParams for Wspr

const NTONES: u32 = 4

const BITS_PER_SYMBOL: u32 = 2

const NSPS: u32 = 8192

const SYMBOL_DT: f32

const TONE_SPACING_HZ: f32

const GRAY_MAP: &'static [u8]

const GFSK_BT: f32 = 1.0

const GFSK_HMOD: f32 = 1.0

const NFFT_PER_SYMBOL_FACTOR: u32 = 1

const NSTEP_PER_SYMBOL: u32 = 16

const NDOWN: u32 = 32