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Colloidal semiconductor nanocrystals (NCs) attract significant interest in recent years due to their narrow and tunable emission wavelength in the visible range, as well as high photoluminescence quantum yield (PLQY), which are highly desired in display technologies. The high-quality NCs have been recognized as vital luminescent materials in realizing next-generation display devices. With further development, NCs with near-unity PLQY have been successfully synthesized through engineering of the core/shell heterostructure. However, as the external quantum efficiency (EQE) of the nanocrystal light-emitting diodes (LEDs) approaches the theoretical limit of about 20%, the low out-coupling factor proposes a challenge of enhancing the performance of a device when using the spherical QDs. Hence, the anisotropic NCs like nanoplatelets (NPLs) are proposed as promising solutions to improve the performance of nanocrystal LEDs. In this review, we will summarize the synthetic strategies of two-dimensional (2D) NPLs at first. Then, we will introduce fundamental concepts of LEDs, the main approaches to realize LEDs based on nanoplatelets, and the recent progress. Finally, the challenges and opportunities of LEDs based on anisotropic NCs are also presented.

Radiation detectors are widely used in physics, material science, chemistry, and biology. Halide perovskites are known for their superior properties including tunable bandgaps and chemical compositions, high defect tolerance, solution-processable...

In order to meet multi-channel, high data rate, intensive computing capacity of modern radar signal processing, a standard, scalable, high-performance general-purpose radar signal processing system platform is proposed. The main processor of this system platform is the DSP and FPGA. In the analysis of different kinds of radar signal processing algorithm, and taking into account the respective advantages and disadvantages of DSP and FPGA, In this paper, a software architecture method for radar signal processing is given to decide how to distribute different algorithm into DSP and FPGA. At last, for a certain type of circular array radar, an implementation of radar signal processing by using the general-purpose radar signal processing system platform is proposed.

As any linear antennas can be considered to be comprised of a large number of dipole antenna, therefore the study of dipole antenna characteristics has a very important significance to the application of the general linear antennas. In this paper, Firstly, the radiation field of the dipole antenna is analyzed, and then the radiation field mathematic model of a specific structural antenna is established. The antenna is composed of two orthogonal half-wavelength dipoles, and the current phase of one dipole is advanced the other by 90°. According to the polarization theory of electromagnetic wave, the polarization of this antenna is discussed. The antenna pattern mathematical formula is deduced in horizontal and perpendicular plane, and the antenna pattern is given in graphics. Finally, a new method is introduced that the directivity of horizontal polarization component can be enhanced by increasing the number of antenna elements in the vertical plane, the simulation result show that this method not only enhance the energy of horizontal direction, but also restrain the radiation of other direction.