Beijing University of Posts and Telecommunications

About: Beijing University of Posts and Telecommunications is a education organization based out in Beijing, Beijing, China. It is known for research contribution in the topics: MIMO & Quality of service. The organization has 39576 authors who have published 41525 publications receiving 403759 citations. The organization is also known as: BUPT.

3-D MIMO: How Much Does It Meet Our Expectations Observed From Channel Measurements?

Abstract: By taking advantage of the elevation domain, three-dimensional (3-D) multiple input and multiple output (MIMO) with massive antenna elements is considered as a promising and practical technique for the fifth Generation mobile communication system. So far, 3-D MIMO is mostly studied by simulation and a few field trials have been launched recently. It still remains unknown how much does the 3-D MIMO meet our expectations in versatile scenarios. In this paper, we answer this based on measurements with $56\times 32$ antenna elements at 3.5 GHz with 100-MHz bandwidth in three typical deployment scenarios, including outdoor to indoor (O2I), urban microcell (UMi), and urban macrocell (UMa). Each scenario contains two different site locations and 2–5 test routes under the same configuration. Based on the measured data, both elevation and azimuth angles are extracted and their stochastic behaviors are investigated. Then, we reconstruct two-dimensional and 3-D MIMO channels based on the measured data, and compare the capacity and eigenvalues distribution. It is observed that 3-D MIMO channel which fully utilizes the elevation domain does improve capacity and also enhance the contributing eigenvalue number. However, this gain varies from scenario to scenario in reality, O2I is the most beneficial scenario, then followed by UMi and UMa scenarios. More results of multiuser capacity varying with the scenario, antenna number and user number can provide the experimental insights for the efficient utilization of 3-D MIMO in future.

6–100 GHz research progress and challenges from a channel perspective for fifth generation (5G) and future wireless communication

Abstract: Radio frequency is a valuable resource for wireless communication systems. The high-frequency band from 6 GHz up to 100 GHz, where continuous and broad spectra exist, is promising to meet the high spectrum requirement of fifth generation (5G) mobile communication systems by 2020. To date, many groups from academia and industry have contributed to devising approaches to allocate and utilize frequency resources from 6 GHz to 100 GHz for 5G and future wireless communication systems. In this paper, we present global efforts to allocate potential frequency bands and field trial progress from 6 GHz to 100 GHz for 5G. From a channel perspective, we summarize research progress and challenges, including channel measurement platforms and channel parameter analysis, both of which are important to extract the inherent channel characteristics and use a high-frequency band for 5G and future wireless communication systems.

Soliton interaction in the higher-order nonlinear Schrödinger equation investigated with Hirota's bilinear method.

Abstract: The soliton interaction is investigated based on solving the higher-order nonlinear Schr\"odinger equation with the effects of third-order dispersion, self-steepening, and stimulated Raman scattering. By using Hirota's bilinear method, the analytic one-, two-, and three-soliton solutions of this model are obtained. According to those solutions, the relevant properties and features of physical and optical interest are illustrated. The results of this paper will be valuable to the study of signal amplification and pulse compression.

Bound vector solitons and soliton complexes for the coupled nonlinear Schrödinger equations

Abstract: Dynamic features describing the collisions of the bound vector solitons and soliton complexes are investigated for the coupled nonlinear Schrodinger (CNLS) equations, which model the propagation of the multimode soliton pulses under some physical situations in nonlinear fiber optics. Equations of such type have also been seen in water waves and plasmas. By the appropriate choices of the arbitrary parameters for the multisoliton solutions derived through the Hirota bilinear method, the periodic structures along the propagation are classified according to the relative relations of the real wave numbers. Furthermore, parameters are shown to control the intensity distributions and interaction patterns for the bound vector solitons and soliton complexes. Transformations of the soliton types (shape changing with intensity redistribution) during the collisions of those stationary structures with the regular one soliton are discussed, in which a class of inelastic properties is involved. Discussions could be expected to be helpful in interpreting such structures in the multimode nonlinear fiber optics and equally applied to other systems governed by the CNLS equations, e.g., the plasma physics and Bose-Einstein condensates.