China Mobile Research Institute

About: China Mobile Research Institute is a based out in . It is known for research contribution in the topics: MIMO & Wireless network. The organization has 579 authors who have published 542 publications receiving 13897 citations.

Distributed optimization for downlink broadband small cell networks

Abstract: Small cell networks have been recognized as a promising technology to realize high spectrum and energy efficiency communications in future wireless networks. However, the capacity of small cell networks is limited by the interference among the links communicating simultaneously. Efficient resource allocation and effective interference management is definitely imperative for small cells. In this paper, we propose an algorithm to optimize the power and subcarrier allocation jointly in order to maximize the weighted sum rate for dense small cell networks. Facing with a large amount of small cells, the optimization problem is in nature a large scale optimization problem. Using advanced decomposition theory, the proposed algorithm can effectively decompose the considered optimization problem into a series of much simpler subproblems which can be efficiently solved in parallel. Finally, simulation results demonstrate that the proposed algorithm enjoys greater performance gain and faster convergence as compared to the existing schemes.

A novel dynamic soft frequency reuse combined with power re-allocation in LTE uplinks

Abstract: In this paper, we propose a novel dynamic soft frequency reuse scheme (ND-SFR) to deal with the inter-cell interference in LTE uplinks under unbalanced traffic loads. The scheme comprises two parts: edge reuse algorithm (ER) and power re-allocation (PR) algorithm. With ER, we can exploit the positions of the cell-edge users to coordinate the inter-cell interference so as to reuse more physical resource blocks (PRB) than previously reported schemes. With PR, we re-allocate the transmission power of users, so as to coordinate the inter-cell interference between cell-edge users and cell-center users in two adjacent cells. The simulation results demonstrate that ND-SFR will improve the capacity or energy efficiency of cell-edge users and meanwhile do little harm to the cell-center users in the neighboring cells.

Preliminary feature and performace comparision between 3GPP LTE Release 8 and IEEE 802.16m

Abstract: This paper presents a feature comparison between the 3rd Generation Partnership Project (3GPP) Long Term Evolution (LTE) Release 8 and Institute of Electrical and Electronics Engineers (IEEE) 802.16m and preliminary system performance comparison. As Orthogonal Frequency Division Multiple Access (OFDMA) mobile broadband air interfaces, LTE and IEEE 802.16m are both International Mobile Telecommunications-Advanced (IMT-Advanced) technologies. LTE and IEEE 802.16m, which both make use of Multiple-Input Multiple-Output (MIMO) channels, have their own features and advantages. This paper compares some features between LTE and IEEE 802.16m in terms of frame structure, effective bandwidth, Hybrid Automatic Retransmission Request (HARQ) and Modulation and Coding Scheme (MCS), which is a valuable replenishment to the former work. The system simulation results show that LTE and IEEE 802.16m achieve similar performance although they are different communication evolution systems from different specification work groups.

A sensing layer network resource allocation model based on trusted groups

Abstract: There are many heterogeneous sensing nodes in the sensing layer of the Internet of Things, and the amount of data transmission is huge, which puts high requirements on the allocation of network bandwidth. At the same time, untrusted sensing nodes maliciously invade network resources. Therefore, how to confirm whether a sensing node is trusted and reasonably allocate network resources is an urgent problem to be solved. To resolve this issue, this paper proposes a sensing network resource allocation model based on trusted groups. Through the sensing node computing environment and behavior measurement, we can identify and exclude untrusted nodes, so the trusted group can be built. Then the network resources are distributed from a global perspective. Based on the available bandwidth of the link, a network resource fusion model of IPv4 and IPv6 is proposed. On this basis, a global network resource allocation model is further proposed. Afterwards, real-time monitoring of data transmission behavior ensures data security during transmission. Simulation experiments show that this mechanism can effectively optimize the bandwidth allocation in the data transmission process and has little effect on the running efficiency of existing network applications. At the same time, it can effectively guarantee the trust of nodes and achieve trusted data transmission.

ORB-SLAM based semi-dense mapping with monocular camera

Abstract: In recent years, Simultaneous Localization And Mapping (SLAM) has been more and more popular especially in the field of unmanned vehicles and augmented reality (AR) applications. The existing feature based SLAM systems such as ORB-SLAM can only estimate sparse mapping and the direct methods such as LSD-SLAM have poor robustness on variety of light intensity. In this paper, we combine the advantages of direct method and indirect method, to accomplish semi-dense mapping based on ORB-SLAM. Our method has two key novelties: (1) when performing epipolar search, we compare the hamming distance of binary descriptor along the epipolar line, and thus the influence of illumination change can be reduced (2) we propose modified bilateral filter to smooth depth estimation. Experimental results show that a denser mapping can be obtained using our system.