A New Very Long Baseline Interferometry Method Based on the Uplink Signal

Abstract

Very long baseline interferometry (VLBI) is widely used for astronomical observations and navigation of deep space receivers. To solve the problems of the downlink signal being excessively weak to be received and the excessively large acquisition time, a new VLBI measurement method based on the uplink signal is proposed. Deep space ground stations can provide radio measurement signals for deep space spacecraft via the uplink. The range, Doppler and VLBI can be determined by the spacecraft through signals from multiple ground stations. In this manner, a higher signal to noise ratio (SNR) can be obtained. This study involves the development of a prompt acquisition algorithm for high dynamic deep space signals. Furthermore, the measurement and tracking of the phases of multiple VLBI stations by deep space receiver employing the uplink are analyzed. The use of the algorithms reduce the acquisition time for deep space receiver, and high precision results can be obtained for the VLBI measurement. Compared with the traditional VLBI method, the ranging error on the same distance is effectively improved, and the angle measurement accuracy is better than delta differential one way ranging (DOR). Because multiple spacecraft are not needed, there are fewer limitations than same beam interferometry (SBI). INDEX TERMS Navigation, very long baseline interferometry, acquisition and tracking, interferometry.

Altimeter + INS/Giant LEO Constellation Dual-Satellite Integrated Navigation and Positioning Algorithm Based on Similar Ellipsoid Model and UKF

“…Other error models for the INS and LEO satellites, such as the gyro error, accelerometer error, ephemeris error, ionospheric and tropospheric error models can be found in the References [24,30,31]. For interference models, such as line-of-sight (LOS)/non-line-of-sight (NLOS), multipath interference model, noise and other interference models can refer to the References [20,[32][33][34][35][36][37]. Here, our noise interference model is consistent with the Gaussian noise interference model adopted in Reference [20]; in addition, due to the complexity of multipath modeling, we will not consider it here.…”

Interferometer direction‐finding system with time‐division multiplexing of spread spectrum signals

“…1 Interferometer DF systems have the advantages of high precision and a simple structure that can be adopted in deep space exploration and DF radar. [2][3][4] However, when the length of the baseline is larger than half of the signal wavelength, it is necessary to solve the integer ambiguity of the phase difference. Thus, the focus of this method is how to solve the integer ambiguity correctly.…”

“…Direction‐finding (DF) systems are mainly divided into the following three types: time difference of arrival, spatial spectrum estimation, and phase interferometer 1 . Interferometer DF systems have the advantages of high precision and a simple structure that can be adopted in deep space exploration and DF radar 2–4 . However, when the length of the baseline is larger than half of the signal wavelength, it is necessary to solve the integer ambiguity of the phase difference.…”