Gen Relativ Gravit (2016) 48:73
Jie Luo 1 · Yuan Tian 1 · Dian-Hong Wang 1 ·Cheng-Gang Qin 2 · Cheng-Gang Shao 2
Received: 2 February 2016 / Accepted: 27 April 2016
© Springer Science+Business Media New York 2016
Abstract ：The Beyond Einstein Advanced Coherent Optical Network (BEACON) mission was designed to achieve an accuracy of 10 −9 in measuring the Eddington parameter γ, which is perhaps the most fundamental Parameterized Post-Newtonian parameter. However, this ideal accuracy was just estimated as a ratio of the measure-ment accuracy of the inter-spacecraft distances to the magnitude of the departure from Euclidean geometry. Based on the BEACON concept, we construct a measurement model to estimate the parameter γ with the least squares method. Influences of the measurement noise and the out-of-plane error on the estimation accuracy are evalu-ated based on the white noise model. Though the BEACON mission does not require expensive drag-free systems and avoids physical dynamical models of spacecraft, the relatively low accuracy of initial inter-spacecraft distances poses a great challenge,which reduces the estimation accuracy in about two orders of magnitude. Thus the noise requirements may need to be more stringent in the design in order to achieve the target accuracy, which is demonstrated in the work. Considering that, we have given thelimitsonthepowerspectraldensityofbothnoisesourcesfortheaccuracyof10 −9 .
Keywords： BEACON mission · The Eddington parameter · The measurement noise ·The out-of-plane error
