Design of Tracking, Telemetry, Command (TT&C) and Data Transmission Integrated Signal in TDD Mode

Abstract

For satellite or aircraft networks, tracking, telemetry, and control (TT&C) and data transmission between different nodes are necessary. Traditional measurement mostly adopts the frequency division duplex (FDD) mode and uses a continuous measurement system to achieve high-precision measurement. However, as the number of network nodes increases, the mode suffers from complex frequency domain allocation, and high-cost measurement and data transmission equipment is required. This paper proposes the integrated signal in time division duplex (TDD) mode to improve frequency utilization to address these circumstances. The proposed signal can transmit the TT&C and data at the same frequency. In addition, the high-precision time-frequency synchronization and relative measurement technology in the TDD mode for distributed spacecraft or aircraft networks are studied. The simulation results show that the signal can work normally when the Doppler extrapolation error is less than a quarter of the integration frequency. The distance extrapolation error should be less than a quarter of the length of a chip. The integrated signal reduces the frequency band occupation and realizes the integration of TT&C and data transmission. In addition, the measurement performance is reduced by only 2~3 dB compared with that of the traditional pure TT&C signal.

Multi-Layer Space Information Networks: Access Design and Softwarization

“…Multi-layer SINs to a large extent is different from the traditional terrestrial networks as the former is generally composed of a multitude of satellites and constellations distributed over different orbits to provide differentiated services with various requirements, ranging from high reliability and low-rate for TT&C subsystems to high throughput data collection for nanosats [34]. Current satellite technologies can also allow on-board regeneration and Layer 3 routing that convert satellites to active network elements rather than simple bent pipe relays.…”

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.…”

Multi-layer Space Information Networks: Access Design and Softwarization

“…Multi-layer SINs to a large extent is different from the traditional terrestrial networks as the former is generally composed of a multitude of satellites and constellations distributed over different orbits to provide differentiated services with various requirements, ranging from high reliability and lowrate for TT&C subsystems to high throughput data collection for nanosats [35]. Current satellite technologies can also allow on-board regeneration and Layer 3 routing that convert satellites to active network elements rather than simple bent pipe relays.…”