Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Precision measurement of gravitational frequency shift of radio signals
  using Rao-Cramer estimates   A method has been developed for precision measurement of the gravitational
frequency shift of communication radio signals between the spacecraft and the
ground tracking station based on the maximum likelihood principle, using the
Rao-Cramer limit estimates for the kinematic parameters associated with orbital
motion. Numerical illustrations of the efficiency of the method are presented
using the example of data obtained in experiments with the Spectr-R satellite
as part of the VLBI system in the "Radioastron" mission. A compensatory
"on-line" technique for suppressing Doppler and atmospheric noise has been
implemented due to the presence of two modes of communication in gravity
sessions: unidirectional (1w) and looped (2w). Recipes for reducing the
magnitude of systematic errors are discussed.

31
The categories of this paper are: ao-sci
37
The categories of this paper are: supr-con
12
The categories of this paper are: nucl-th
26
The categories of this paper are: bayes-an
34
The categories of this paper are: chem-ph
1
The categories of this paper are: cs
20
The categories of this paper are: acc-phys
29
The categories of this paper are: funct-an
14
The categories of this paper are: math-ph
36
The categories of this paper are: cmp-lg
4
The categories of this paper are: cond-mat
16
The categories of this paper are: stat
11
The categories of this paper are: hep-lat
30
The categories of this paper are: q-alg
9
The categories of this paper are: nlin
18
The categories of this paper are: econ