Abstract: An angular domain channel estimation method based on matrix reconstruction for a symmetrical nonuniform array is a combined two-stage channel estimation and channel equalization scheme provided based on an SNLA model. In a first stage, a matrix reconstruction method is used to estimate a path AOA, and compared with traditional channel estimation based on ULA, the matrix reconstruction method achieves a higher resolution ratio. In a second stage, an LS method is used to obtain a path gain. According to the angular domain channel estimation method, a mean square error of channel estimation, a bit error of data transmission and complexity of a traditional scheme are significantly reduced. A simulation result indicates that compared with the traditional method, the angular domain channel estimation method can achieve a lower MSE and BER.

Abstract: A method for preparing an ultrathin two-dimensional (2D) monocrystalline nanosheet, the method including: 1) placing BiX3 powder where X=I, Br, or Cl in a crucible, and putting the crucible on a first heating zone of a furnace disposed at a gas inlet of a quartz tube; placing substrates covered with metal sheets on a second heating zone of the furnace disposed at a gas outlet of the quartz tube; 2) vacuumizing the quartz tube; pumping Ar gas into the quartz tube until the air pressure is 101.325 kPa; pumping a carrier gas into the quartz tube; and 3) heating and maintaining the second heating zone; heating the first heating zone for BiX3 evaporation until producing chemical reaction between BiX3 and the metal sheets, and preparing ultrathin 2D nanosheets on the substrates simultaneously; and cooling the substrate naturally to 15-30° C.

Abstract: A method for preparing an ultrathin two-dimensional (2D) monocrystalline nanosheet, the method including: 1) placing BiX3 powder where X=I, Br, or Cl in a crucible, and putting the crucible on a first heating zone of a furnace disposed at a gas inlet of a quartz tube; placing substrates covered with metal sheets on a second heating zone of the furnace disposed at a gas outlet of the quartz tube; 2) vacuumizing the quartz tube; pumping Ar gas into the quartz tube until the air pressure is 101.325 kPa; pumping a carrier gas into the quartz tube; and 3) heating and maintaining the second heating zone; heating the first heating zone for BiX3 evaporation until producing chemical reaction between BiX3 and the metal sheets, and preparing ultrathin 2D nanosheets on the substrates simultaneously; and cooling the substrate naturally to 15-30° C.

Abstract: An exemplary barcode decoding chip includes a scan module, a boundary identification module, a direction identification module, a bar space boundary processing module, a symbol parameter identification module, a symbol character extraction module, and a decoding module.

Abstract: An exemplary QR barcode decoding chip includes a characteristic searching unit configured for searching for a characteristic pattern in the barcode image to determine pixel coordinates of the characteristic pattern; a barcode parameter acquiring unit configured for acquiring a barcode parameter according to the pixel coordinates of the characteristic pattern; a version/format parameter acquiring unit configured for acquiring a version/format parameter; a correction characteristic acquiring unit configured for searching for a characteristic position in the barcode image and acquiring a correction characteristic according to the characteristic position; a module information processing unit configured for calculating a grayscale value corresponding to a module according to the version/format parameter, the barcode parameter and the correction characteristic; a binarizing unit configured for binarizing the module; a codeword extracting unit configured for extracting a codeword according to the binarized module; a

Abstract: An exemplary barcode decoding chip includes a scan module, a boundary identification module, a direction identification module, a bar space boundary processing module, a symbol parameter identification module, a symbol character acquisition module, and a decoding module.

Abstract: An exemplary QR barcode decoding chip includes a characteristic searching unit configured for searching for a characteristic pattern in the barcode image to determine pixel coordinates of the characteristic pattern; a barcode parameter acquiring unit configured for acquiring a barcode parameter according to the pixel coordinates of the characteristic pattern; a version/format parameter acquiring unit configured for acquiring a version/format parameter; a correction characteristic acquiring unit configured for searching for a characteristic position in the barcode image and acquiring a correction characteristic according to the characteristic position; a module information processing unit configured for calculating a grayscale value corresponding to a module according to the version/format parameter, the barcode parameter and the correction characteristic; a binarizing unit configured for binarizing the module; a codeword extracting unit configured for extracting a codeword according to the binarized module; a