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Jointly building 5G network and sharing network infrastructure is carrying out by a few network operators in the world actively and is regarded as a practical means to expedite the roll-out of commercial 5G with seamless coverage and user experience guarantees but significantly reduced investment. As of 2020, China Telecom and China Unicom have achieved more than 60% of joint construction and sharing gains, saving more than 10 billion yuan in investment. In such a background, and in the process of NSA network evolution to SA, how to bear 5G voice services in the shared network infrastructure gets quite a few technical options. This paper investigates the technical details of 5G network sharing schemes adopted by network operators in China and presents a voice-bearing technology designed for the co-built and shared network. Performance results from a few field tests prove the technical feasibility of voice bearing in the co-built and shared network, which further illustrates the technical competitiveness of the co-built and shared 5G network.

The Cook-Toom algorithm is widely used in short-length linear convolution, which is the building block of large points convolution algorithms. This paper proposes improved parallel finite impulse response (FIR) filter structures for linear-phase FIR filter, which is based on the Cook-Toom algorithm. In the proposed structures, Cook-Toom algorithm is used to reduce the number of sub-filters, and the symmetric properties of the linear-phase FIR filter’s coefficients is used to further reduce the number of multipliers in sub-filters. Compared with the reported FFA and ISCA parallel FIR filter structures, the proposed method can substantially reduce the computational complexity. Specifically, for a 8-parallel 144-tap filter, the proposed design saves 18 multipliers (5%), 45 adders (7.9%) compared with the structure based on Winograd convolution algorithm [7].

The output frequency response for most DACs rolls off according to the sin(x)/x frequency-response envelope [1]. This paper derives a FIR filter which is designed in the minimax sense with the ripple constraints as the design criteria for the frequency response compensation of DACs. The filter order estimation function under the criterion gives a detailed filter design configuration method, which can effectively shorten the design time and provide an accurate resource configuration reference for the top-level system design [2]. The simulation example verifies the advantages of the compensation filter in minimax sense and shows the performance of the compensation filter and the accuracy of the order estimation function.

Sample-and-hold (S/H) mismatches incur undesired error which affects the time-interleaved analog-to-digital converter(TIADC)‘s performance. A few calibration methods have been proposed for S/H mismatches which either need training signals or cannot apply to the signals with narrow frequency range around the center of the Nyquist band. This paper proposes a statistics-based correction algorithm for S/H mismatch in 2-channel TIADCs. The mismatch parameter is identified by assuming the modulo two quasi-stationary property of the input samples, and the mismatch-induced error is reconstructed by employing variable multipliers and differentiators in Richardson iteration. Simulation results illustrate the effectiveness of the proposed method and the advantage to the method based on input-free band (IFB).

In order to effectively overcome the defects of local and global pheromone updating for the basic Ant Colony Algorithm, this paper has proposed a new improved Ant Colony Algorithm based on the dynamic adaptive weight in the updating strategy. The proposed algorithm can update pheromone dynamically and adaptively according to the change of taboo lists and the quality of iteration-best solutions. By the experiments of several typical Traveling Salesman Problems (TSP), the proposed algorithm is clearly better than several other typically Ant Colony Algorithms in the convergence speed and the solution quality. The test results can reflect its effectiveness and feasibility.

Dust aerosol heavily affects air quality of northern China and regional radiation balance. Takelamagan desert emits a lot of dust aerosol every year and Tazhong observation station located in the center of Takelamagan desert supplies an opportunity to observe dust aerosol in a near distance. This paper analyzed annual variability of dust aerosol based on Cimel 318-II sun photometer and further made a correlation analyze of aerosol optic thickness (AOT), visibility, inhalable particulate matter (PM10) concentration, and total suspended particle (TSP) concentration for two years (2003 and 2004). The result indicates that AOT at 440nm in spring is bigger than that in other seasons. PM10 concentration and visibility has a negative relationship of power function. AOT at 440nm and visibility also has a negative relationship of power function. However, AOT at 440nm and PM10 concentration has a positive relationship, which means that an increase of dust concentration will result in an increase of AOT at 440nm.