/**
 * Convert sensor confidence (0-1) to measurement noise variance for EKF.
 *
 * High confidence (1.0) → low noise → measurement trusted more
 * Low confidence (0.1) → high noise → measurement trusted less
 *
 * The returned value is suitable for use as the R (measurement noise) parameter
 * in a Kalman filter update step.
 *
 * @param confidence - Confidence score from 0 to 1
 * @param baseAccuracy - Base accuracy in meters (e.g., GPS reported accuracy)
 * @returns Measurement noise variance (higher = less trust in measurement)
 *
 * @example
 * ```ts
 * // High confidence GPS reading with 5m accuracy
 * const noise1 = confidenceToNoise(0.9, 5); // Low noise
 *
 * // Low confidence GPS reading with 5m accuracy
 * const noise2 = confidenceToNoise(0.1, 5); // High noise (9x more)
 * ```
 */
export declare function confidenceToNoise(confidence: number, baseAccuracy: number): number;