Nanjing University of Posts and Telecommunicatins

Hongbo Zhu

Wenjun Lv

Qi Zhu

Xiaohui Li

Han Wu

Xiaofei Li

Jianyuan Wang

Sijie Li

Zhuang Li

Zhibin Zhao

Longxiang Yang

Yun Shao

Zhifang Wu

Yin Xu

Jun Zhang

Yongjin Wang

Jialei Yuan

Shanshan Gu

Guixia Zhu

Dan Bai

Xiumei Wang

Yin Lu

Kang Liu

Weili Zhang

Yuanyuan Tang

Chuying Yang

Yihuang Qu

Taosen Li

Jiacheng Lu

Shu Cai

Leijie Wang

Hairong Wang

A downlink channel estimation method based on a co-prime array in asymmetric massive MIMO architecture is provided. First, an uplink and downlink asymmetric receiving and transmitting system model based on a co-prime array is established, and a deviation of the frequency domain direction caused by array broadband signals is observed; then, uplink receiving is performed to estimate an uplink channel, and channel parameters such as the number of paths, the angle of arrival and the path gain are recovered; and finally, a downlink channel is reconstructed based on the channel parameters recovered according to the uplink channel. By means of the high angular resolution of the co-prime array, the problem that a recovered uplink channel cannot be directly used for pre-coding of a downlink channel is solved.

Asymmetric massive MIMO channel estimation method based on co-prime array

A user matching and power distribution methods for a MIMO-NOMA downlink communication system is provided. The user matching method includes: dividing all users into a strong user group and a weak user group according to a channel gain sorting result; and sequentially selecting a user in the strong user group, calculating a correlation coefficient between the user and each user in the weak user group, selecting a weak user with the highest correlation coefficient as a weak user in a cluster where the strong user is located, and excluding matched users from respective user groups, until the matching between all strong users and weak users are completed. The present invention enables weak users in a cluster to experience less inter-cluster interference in scenarios where the channel correlation between users is relatively low, thereby improving the total throughput of the communication system.

User matching and power distribution methods for MIMO-NOMA downlink communication system

A method for selecting a content forwarding node in a vehicle ad-hoc network on the basis of service type, comprising the following steps: calculating a bandwidth occupation proportion factor according to the type of requested content information and a bandwidth occupation situation of a neighboring vehicle which can perform forwarding in a one-hop transmission range; defining a virtual arrival time of a candidate forwarding vehicle to an initial request vehicle according to the distance between the neighboring vehicle and the initial request vehicle and a driving speed of the neighboring vehicle; calculating a forwarding node impact factor according to the bandwidth occupation proportion factor and the virtual arrival time; and selecting a forwarding node according to the forwarding node impact factor.

Method for selecting content forwarding node in vehicle ad-hoc network on the basis of service type

The present invention discloses a triple-resonant null frequency scanning antenna, which belongs to the technical fields of the Internet of Things and microwave. The triple-resonant null frequency scanning antenna comprises a circular sector magnetic dipole arranged on a medium substrate, and rectangular notches are symmetrically arranged on a sector patch of the circular sector magnetic dipole. The circular sector magnetic dipole is fixed on the medium substrate by a second shorting pin and third shorting pins, an flared angle of the circular sector magnetic dipole is a first central angle, and two third shorting pins are present and are symmetrically arranged on both sides of the angular bisector of the first central angle.

Triple-resonant null frequency scanning antenna

The present invention discloses a sector dual-resonant dipole antenna. Radiation elements of the antenna are two identical sector patches. Two identical rectangular notches can be symmetrically arranged or two identical tuning stubs can be symmetrically loaded on the sector patches at positions deviating from the central axis of the two sector patches. Exciting points are symmetrically arranged on sides of the sector patches close to a central axis. The present invention realizes a wide beamwidth radiation characteristic through a two-dimensional sectorial resonator, and then the notches are arranged or the tuning stubs are loaded at appropriate positions of two arms of the sectorial resonator, and thereby a dual-resonant characteristic can be realized within a working band.

Sector dual-resonant dipole antenna

The present disclosure provides an adaptive modulation method for a naive Bayes classifier-based energy harvesting relay system. First, a sending end determines its modulation mode based on a status of a data buffer of a relay, so that sent data does not exceed a storage capability of the relay. Then, based on data sent by the sending end, and channel status information and energy harvesting status information within a period of time, the relay determines an optimal modulation mode used by the relay within the period of time. After that, the modulation mode, the channel status information, and the energy harvesting status information are used as training data to obtain a classification model based on a naive Bayes classifier algorithm. In this way, the relay can adaptively select a modulation mode when only knowing of channel information and energy information in a current timeslot.

Adaptive modulation method for Bayes classifier-based energy harvesting relay system

A wide-beam planar backfire and bidirectional circularly-polarized antenna. An entire planar sectorial magnetic dipole is of a semi-closed structure, the planar sectorial magnetic dipole comprises two identical sectorial patches and a vertical short-circuit wall, and the vertical short-circuit wall is connected with straight sides of the two sectorial patches along a radial direction of the planar sectorial magnetic dipole; two sets of concentric annular electric dipoles are respectively used as a top concentric annular radiating element and a bottom concentric annular radiating element, as well as a top concentric annular reflector and a bottom anti-concentric annular reflector; and the top concentric annular radiating element is connected with an upper surface of the planar sectorial magnetic dipole through a top connecting branch, and the bottom concentric annular radiating element is connected with a lower surface of the planar sectorial magnetic dipole through a bottom connecting branch.

Wide-beam planar backfire and bidirectional circularly-polarized antenna

By using various anisotropic silicon etching techniques, a silicon substrate layer () and an epitaxial buffer layer () under the device structure are removed to obtain a monolithic photonic integration of silicon substrate suspended light-emitting diode (LED) with optical waveguide, and an ultra-thin device monolithically integrated with a suspended LED and an optical waveguide is obtained by further using the nitride back thinning etching technique. Therefore, internal loss of the LED is reduced and light emitting efficiency is improved. In the device according to the present disclosure, the light source and the optical waveguide are integrated on the same wafer, which solves the problem of monolithic integration of planar photons, enables the light emitted by the LED to be transmitted along the optical waveguide, addresses the problem of transmission of light in the optical waveguide, and implements the function of transmitting light within a plane.

Integrated photonic device comprising hollowed silicon substrate-based LED and optical waveguide and manufacturing method thereof

Growing community of inventors

Nanjing, China

Hongbo Zhu