Huawei

About: Huawei is a company organization based out in Shenzhen, China. It is known for research contribution in the topics: Terminal (electronics) & Node (networking). The organization has 41417 authors who have published 44698 publications receiving 343496 citations. The organization is also known as: Huawei Technologies & Huawei Technologies Co., Ltd..

On/off macrocells and load balancing in heterogeneous cellular networks

Abstract: The rate distribution in heterogeneous networks (HetNets) greatly benefits from load balancing, by which mobile users are pushed onto lightly-loaded small cells despite the resulting loss in SINR. This offloading can be made more aggressive and robust if the macrocells leave a fraction of time/frequency resource blank, which reduces the interference to the offloaded users. We investigate the joint optimization of this technique - referred to in 3GPP as enhanced intercell interference coordination (eICIC) via almost blank subframes (ABSs) - with offloading in this paper. Although the joint cell association and blank resource (BR) problem is nominally combinatorial, by allowing users to associate with multiple base stations (BSs), the problem becomes convex, and upper bounds the performance versus a binary association. We show both theoretically and through simulation that the optimal solution of the relaxed problem still results in an association that is mostly binary. The optimal association differs significantly when the macrocell is on or off; in particular the offloading can be much more aggressive when the resource is left blank by macro BSs. Further, we observe that jointly optimizing the offloading with BR is important. The rate gain for cell edge users (the worst 3–10%) is very large - on the order of 5–10x - versus a naive association strategy without macrocell blanking.

Spatial spectrum holes for cognitive radio with relay-assisted directional transmission

Abstract: Spectrum hole (SH) is defined as a spectrum band that can be utilized by unlicensed users, which is a basic resource for cognitive radio (CR) systems Most of existing contributions detect SHs by sensing whether a primary signal is present or absent and then try to access them so that the CR and primary users use the spectrum band either at different time slots or in different geographic regions In this paper, we propose a novel scheme with relays or directional relays for CR users to exploit new spectrum opportunity, called spatial SH It can provide higher spectrum efficiency by coexistence of primary and CR users at the same region, time, and spectrum band In particular, when the spectrum opportunity of a direct link from a CR transmitter to a CR receiver does not appear, our scheme may still establish the communication through indirect links, ie, other CR users act as relay stations to assist the communication by using other spatial domains Furthermore, we analyze the successful communication probabilities of CR users and demonstrate that the spectrum efficiency can be considerably improved by our scheme

Controller placement and flow based dynamic management problem towards SDN

Abstract: The SDN architecture decouples the control plane and data plane, and multiple controllers are adopted to solve the scalability and reliability problem in SDN. However, most of the researches are focused on the control architecture and ignore the controller placement problem. Moreover, the mapping between the switches and controllers are static in current proposals, which will lead to the load unbalance of controllers under dynamic flow variations. In this paper, we define a new controller placement metric considering the node weight for a single domain at first, and then propose a dynamic switch migration algorithm to adapt to the flow dynamics and realize controller load balance in multiple SDN domains. Finally, a simple simulation platform is built to verify the proposed scheme.

Multi-Panel MIMO in 5G

Abstract: Massive MIMO is one of the key enabling technologies in 5G wireless communications. A large number of antenna elements bring extra degrees of freedom for increasing the throughput and considerable beamforming gains for improving the coverage. In practice, a large number of antenna elements can be assembled into multiple antenna panels for the purpose of cost reduction and power saving. Multi-panel MIMO is expected to become promising for millimeter-wave massive MIMO systems. This article gives an overview of multi-panel MIMO systems, including downlink, uplink, and non-coherent transmissions, and discuss research challenges and future directions of multi-panel MIMO. We also propose new multi-panel codebook design and corresponding CSI feedback design for 5G systems as well as non-coherent MIMO transmission.