# Estimation

State estimation filters and measurement models for orbit determination.

The estimation module provides sequential filters for processing measurements and refining spacecraft state estimates. It includes built-in measurement models for GPS-like observations and supports user-defined custom models.

## See Also

- [Estimation Guide](../../learn/estimation/index.md) - Concepts, workflows, and examples
- [Common Types](common_types.md) - Configuration and data structures
- [Extended Kalman Filter](extended_kalman_filter.md) - EKF class reference
- [Measurement Models](measurement_models.md) - Built-in model reference