# Configuration

`ReceiverConfig` owns RF, acquisition, tracking, front-end, and fixed-point
dataclasses. YAML loading is strict: a misspelled field is an error.

Important validation rules include positive sampling/loop rates, a real IF
strictly below Nyquist, integer sample counts per integration interval,
ordered correlator tap spacing, explicit FFT length when requested, E1B
bit-transition protection beyond 4 ms, and E1C secondary-code handling beyond
4 ms. E1B tracking is conservatively limited to 4 ms until navigation-symbol
synchronization is implemented.

`intermediate_frequency_hz` may be nonzero for either real or analytic input.
The front end always outputs complex baseband and divides the effective sample
rate by the integer decimation factor. Acquisition/tracking must use that output
rate.

Acquisition parallelism fields expose future hardware/software scheduling but
do not change numerical results. `zero_padding_mode: none` provides the exact
N-sample circular correlation. A longer FFT changes the sampled numerical
correlation/edge convention; it is not additional physical delay information.

Default YAML files:

- `e1_default.yaml`: requested 16.368 MHz nominal defaults.
- `acquisition_example.yaml`: faster 4.092 MHz executable search.
- `tracking_example.yaml`: 4.092 MHz tracking defaults.