Impact of tone errors on gravity field solutions in NGGM concepts

In order to meet the upcoming challenges of climate change, it is necessary to understand the different Earth system processes in more detail and to monitor them. With satellite gravity missions it is possible to continuously measure and observe mass transport processes on Earth globally.  For the current study on Next Generation Gravity Missions (NGGMs) which is called Mass Change and Geosciences International Constellation study (MAGIC) various parameters are subject of the investigation. One aspect is the instrument behavior and its impact on gravity field performance. Besides stochastic noise sources, deterministic errors are present in the instrument measurements, mainly caused by environmental variations on the satellites. These disturbances are generated by temperature variations that occur when passing through sun illuminated and shadow areas, as well as magnetic field variations. As a consequence, periodic errors occur at integer multiples of the orbital frequency.           
In this contribution we want to analyze the impact of the errors on gravity field solutions and provide the findings generated within the MAGIC study. In detail we want to present the results for GRACE-like and Bender-type constellation for scenarios considering an instrument only-case and a full-noise case including temporal gravity field. Depending on the amplitude of the tone errors, they can affect the complete spherical harmonic spectrum of the solutions. To mitigate the effect of tone errors, it is possible to encounter them in data processing e.g. by applying notch filters on the integer multiple of the orbital frequency. As a result of this approach, tone errors affect only the very low harmonic coefficients, but the remaining coefficients can be estimated with good quality.