Title: Benefit of enhanced electrostatic and optical accelerometry for future gravimetry missions Show Chinese title

Title: 增强静电和光学加速度计对未来重力任务的好处

Abstract: Twenty years of gravity observations from various satellite missions have provided unique data about mass redistribution processes in the Earth system. This paper studies the benefit of enhanced electrostatic and novel optical accelerometers and gradiometers for the future gravimetry missions. One of the limiting factors in the current space gravimetry missions is the drift of the Electrostatic Accelerometers (EA). This study focuses on the modeling of enhanced EAs with laser-interferometric readout, so called 'optical accelerometers', and on evaluating their performance for gravity field recovery in future satellite missions. In this paper, we simulate gravimetry missions in multiple scopes, applying the various software modules for satellite dynamics integration, accelerometer (ACC) and gradiometer simulation and gravity field recovery. The total noise budget of the modeled enhanced Electrostatic and optical ACCs show a similar sensitivity as the ACC concepts from other research groups. Parametrization w.r.t. ACCs test mass (TM) weight and the gap between the test mass and surrounding electrode housing confirmed previously known results that an ACC with a heavier TM and larger gap will have better performance. Our results suggest that the anticipated gain of novel ACCs might at some point be potentially limited by noise from the inter-satellite laser ranging interferometry. In order to present the advantage of the novel sensors, time-variable background models and associated aliasing errors were not considered in our simulations. Utilization of enhanced EA and optical ACC show a significant improvement of accuracy w.r.t. current GRACE-like EA. Also, their benefit in double satellite pairs in a so called 'Bender' constellations as well as in the combination of low-low satellite-to-satellite tracking with cross-track gradiometry has been investigated. Show Chinese abstract

Abstract: 二十年来，来自各种卫星任务的重力观测提供了关于地球系统质量再分布过程的独特数据。 本文研究了增强型静电和新型光学加速度计和梯度计对未来重力任务的好处。 当前空间重力任务的一个限制因素是静电加速度计（EA）的漂移。 本研究重点在于增强型EA的建模，采用激光干涉读出，称为“光学加速度计”，并评估其在未来的卫星任务中恢复重力场的性能。 在本文中，我们在多个范围内模拟重力任务，应用各种软件模块进行卫星动力学积分、加速度计（ACC）和梯度计模拟以及重力场恢复。 所建模的增强型静电和光学ACC的总噪声预算显示出与其它研究小组的ACC概念相似的灵敏度。 相对于ACC测试质量（TM）重量和测试质量与周围电极外壳之间的间隙的参数化确认了之前已知的结果，即具有更重的TM和更大间隙的ACC将具有更好的性能。 我们的结果表明，新型ACC的预期增益可能在某种程度上受到星间激光测距干涉仪噪声的限制。 为了展示新型传感器的优势，在我们的模拟中未考虑时间变化的背景模型和相关的混叠误差。 使用增强型EA和光学ACC显示了相对于当前GRACE-like EA的显著精度改进。 此外，还研究了它们在所谓的“Bender”星座中的双卫星对以及低低卫星间跟踪与横轨梯度计组合中的优势。