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In this perspective, we outline that a space borne gravitational wave detector network combining LISA and Taiji can be used to measure the Hubble constant with an uncertainty less than 0.5% in ten years, compared with the network of the ground based gravitational wave detectors which can measure the Hubble constant within a 2% uncertainty in the next five years by the standard siren method. Taiji is a Chinese space borne gravitational wave detection mission planned for launch in the early 2030 s. The pilot satellite mission Taiji-1 has been launched in August 2019 to verify the feasibility of Taiji. The results of a few technologies tested on Taiji-1 are presented in this paper. Gravitational wave astronomy has opened the door to test general relativity and the effect of gravity in the Universe. The authors present the capabilities of an overlap between space gravitational wave detectors LISA and Taiji to constrain the Hubble constant to 0.5%, in 10 years, and what can be learned from the satellite pilot Taiji-1 launched in 2019.

The error correction capability of BCH is very strong, especially for the short and medium length of codes, which performance reaches the theory value. Besides, it has a strict algebraic structure, which plays an important role in the encode theory. But traditional serial BCH has a low throughput, so it cannot satisfy high speed communication. This paper designed a parallel synchronization encode and decode algorithm, and used FPGA to simulate. Experiment result shows that the proposed algorithm can satisfy the requirement of code rate and hardware resources consumption, so the algorithm has a very useful practical value.

We need to achieve real-time parameter control and process a large number of complex numerical calculations in the research of satellite mobile communications fading channel. MATLAB has powerful numerical calculation functions and graphing display characteristics, VC++ has powerful functions to make program interface and can achieve port operation, real-time processing. MATLAB and VC++ mixed programming combines the advantages of both languages and provides strong technical support to the research of satellite mobile communications fading channel. This paper introduces the calculation model of satellite mobile communications fading channel and presents the process of mixed programming. The complex calculation of fading channel is completed and the results are presented.

This paper proposes an adaptive power allocation in multiple-input multiple-output (MIMO) spatial multiplexing slow fading channels, which improves spectral efficiency and reduces the complexity of systems at the same time. Under the constraint of the same signal-to-interference and noise ratio (SINR) at each receive antenna, an iteration formula of power allocation algorithm for transmit antennas is derived. Besides, for a certain channel gain matrix, the same SINR value at each receive antenna is proved to have the limit value. The simulations of the proposed adaptive power allocation show that the algorithm is effective and can reach the convergence fast.