Applying TDI to Hardware-Simulated Data

TL;DR

This paper presents a hardware-in-the-loop testbed for applying realistic delays to signals in LISA-like systems, demonstrating its low noise addition and successful gravitational wave signal extraction using TDI algorithms.

Contribution

It introduces a novel hardware-in-the-loop testbed that simulates realistic delays and noise for LISA data analysis, bridging the gap between instrument development and software simulations.

Findings

Testbed adds minimal noise across LISA spectrum

Successfully injected and extracted gravitational wave signals

Demonstrates feasibility of hardware-in-the-loop approach

Abstract

Many years of development have gone into producing instruments that meet the required noise performance of the LISA interferometric detection system. Concurrently, software simulations have been used to extensively develop the data analysis libraries to be used in the LISA pipeline, not least among which are the Time Delay Interferometry (TDI) algorithms. To bridge the gap between these two, we are developing a hardware-in-the-loop testbed to apply realistic, time-varying delays to signals traveling between phasemeters. We have shown that the testbed adds a sufficiently low amount of noise across the entire relevant LISA spectrum. We have also injected a realistic gravitational wave signal, generated via the LISA Data Challenge codebase, and successfully extracted it using TDI to remove the obscuring frequency noise of the carrier signal. Future efforts will expand the testbed to create a representative simulation of the entire LISA constellation, with an eye towards its use as a tool to aid in the development of the LISA data analysis pipelines.