Spacecraft VLBI and Doppler tracking: algorithms and implementation

Radiowave Phase Scintillation and Precision Doppler Tracking of Spacecraft

Phase scintillation caused by propagation through irregularities in the solar wind, ionosphere, and troposphere, introduces noise in spacecraft radio science experiments. In precision Doppler tracking observations, scintillation can be the dominant noise source; statistics of this propagation noise are necessary for experiment planning and in design of optimum signal processing procedures. Here...

Low-Frequency Gravitational Wave Searches Using Spacecraft Doppler Tracking

This paper discusses spacecraft Doppler tracking, the current-generation detector technology used in the low-frequency (∼millihertz) gravitational wave band. In the Doppler method the earth and a distant spacecraft act as free test masses with a ground-based precision Doppler tracking system continuously monitoring the earth-spacecraft relative dimensionless velocity 2Δv/c = Δν/ν0, where Δν is ...

Narrow-band Searches for Gravitational Radiation with Spacecraft Doppler Tracking

We discuss a filtering technique for Teducing the two-way Doppler frequency jluctuations of noise sources localized in space (like the troposphere, or the master clock) that aflect the sensitivity of spacecraft Doppler tmcking searches for gravitational mdiation. This method takes advantage of the sinusoidal behavior of the tmnsfer function to the Doppler observable of these noise sources, whic...

Doppler and bearing tracking using fuzzy adaptive unscented Kalman filter

The topic of Doppler and Bearing Tracking (DBT) problem is to achieve a target trajectory using the Doppler and Bearing measurements. The difficulty of DBT problem comes from the nonlinearity terms exposed in the measurement equations. Several techniques were studied to deal with this topic, such as the unscented Kalman filter. Nevertheless, the performance of the filter depends directly on the...

Design Algorithms for Doppler MTI and Filters (Using Chebyshev Approximation)