arXiv subjects

Miguel Dovale-Álvarez

Publications and source records attributed to Miguel Dovale-Álvarez.

4 recordsLinked to original sources

arXiv2026

Fundamental Limitations of Absolute Ranging via Deep Frequency Modulation Interferometry

Deep frequency modulation interferometry (DFMI) resolves phase ambiguity in absolute distance measurements by jointly estimating two length-encoding parameters: the coarse and unambiguous effective modulation depth ($m$), and the fine but ambiguous interferometric phase ($ϕ$). We establish a comprehensive framework quantifying the fundamental precision limits and practical accuracy constraints of this technique. A Fisher-information analysis defines the intrinsic estimator precision for $m$ and $ϕ$, while the contribution of carrier frequency drift introduces an additional, time-dependent source of random error. Numerical simulations reveal a structured error landscape with previously unrecognized ``valleys of robustness,'' where systematic biases from common hardware imperfections are suppressed by orders of magnitude. An analytical model based on signal orthogonality explains their origin and predicts their locations. The results yield a consolidated error budget accounting for both random and systematic errors, providing a quantitative design paradigm for absolute length metrology via DFMI.

physics.optics↗

arXiv2025

The DeepFMKit Python package: A toolbox for simulating and analyzing deep frequency modulation interferometers

Deep Frequency Modulation Interferometry (DFMI) is an emerging laser interferometry technique for high-precision metrology, offering picometer-level displacement measurements and the potential for absolute length determination with sub-wavelength accuracy. However, the design and optimization of DFMI systems involve a complex interplay between interferometer physics, laser technology, multiple noise sources, and the choice of data processing algorithm. To address this, we present DeepFMKit, a new open-source Python library for the end-to-end simulation and analysis of DFMI systems. The framework features a high-fidelity physics engine that rigorously models key physical effects such as time-of-flight delays in dynamic interferometers, arbitrary laser modulation waveforms, and colored noise from user-defined $1/f^α$ spectral densities. This engine is coupled with a suite of interchangeable parameter estimation algorithms, including a highly-optimized, parallelized frequency-domain Non-linear Least Squares (NLS) for high-throughput offline analysis, and multiple time-domain Extended Kalman Filter (EKF) implementations for real-time state tracking, featuring both random walk and integrated random walk (constant velocity) process models. Furthermore, DeepFMKit includes a high-throughput experimentation framework for automating large-scale parameter sweeps and Monte Carlo analyses, enabling systematic characterization of system performance. DeepFMKit's modular, object-oriented architecture facilitates the rapid configuration of virtual experiments, providing a powerful computational tool for researchers to prototype designs, investigate systematic errors, and accelerate the development of precision interferometry.

physics.ins-det↗

arXiv2025

Complete Catalog of Laser Locking Configurations for LISA

The Laser Interferometer Space Antenna (LISA) will enable direct observations of low-frequency gravitational waves, offering unprecedented insight into astrophysical and cosmological phenomena. LISA's heterodyne interferometric measurement system requires phase-locking five of its six onboard lasers with tunable frequency offsets to ensure that all beatnotes remain within the metrology system's operational range, despite Doppler-induced frequency shifts. The selection of these offset frequencies -- collectively forming a frequency plan -- is a complex optimization problem constrained by the spacecraft's orbital dynamics and instrument limitations. While previous work established an algorithmic solution for deriving time-dependent frequency plans, this study takes a complementary approach by systematically analyzing and cataloging all possible laser locking configurations. We present an automated method to explore, validate, and classify viable locking schemes, identifying 36 unique non-frequency-swapping configurations and 72 additional frequency-swapping configurations for an arbitrary choice of primary laser. This exhaustive classification provides a foundation for frequency planning across the full range of operational scenarios.

physics.ins-det↗

arXiv2024

Frequency planning for LISA

The Laser Interferometer Space Antenna (LISA) is poised to revolutionize astrophysics and cosmology in the late 2030's by unlocking unprecedented insights into the most energetic and elusive astrophysical phenomena. The mission envisages three spacecraft, each equipped with two lasers, on a triangular constellation with 2.5 million-kilometer arm-lengths. Six inter-spacecraft laser links are established on a laser-transponder configuration, where five of the six lasers are offset-phase-locked to another. The need to determine a suitable set of transponder offset frequencies precisely, given the constraints imposed by the onboard metrology instrument and the orbital dynamics, poses an interesting technical challenge. In this paper we describe an algorithm that solves this problem via quadratic programming. The algorithm can produce concrete frequency plans for a given orbit and transponder configuration, ensuring that all of the critical interferometric signals stay within the desired frequency range throughout the mission lifetime, and enabling LISA to operate in science mode uninterruptedly.

physics.ins-det↗