Xianbin Wang

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Cognitive small cell networks have been envisioned as a promising technique for meeting the exponentially increasing mobile traffic demand. Recently, many technological issues pertaining to cognitive small cell networks have been studied, including resource allocation and interference mitigation, but most studies assume non-cooperative schemes or perfect(More)
Distributed web servers on the immensely expanding Internet require high scalability and availability to provide efficient services to millions of clients on the web. To provide rapid responses to enormous number of client requests, load balancing is an important technique to evenly distribute the requests to web servers. In this paper, we propose a(More)
This paper investigates advanced energy-efficient wireless systems in orthogonal frequency-division multiple access (OFDMA) downlink networks using coordinated multipoint (CoMP) transmissions between the base stations (BSs) in a heterogeneous network (HetNet), which is adopted by Third-Generation Partnership Project (3GPP) Long-Term Evolution (LTE)-Advanced(More)
Sparsely spread code division multiple access (SCDMA) is a non-orthogonal superposition coding scheme that permits a base station simultaneously communicates with multiple users over a common channel. The detection performance of an SCDMA system is mainly determined by its signature matrix, which should be sparse to guarantee large Euclidean distance for(More)
Due to the broadcast nature of radio propagation, wireless transmission can be readily overheard by unauthorized users for interception purposes and is thus highly vulnerable to eavesdropping attacks. To this end, physical-layer security is emerging as a promising paradigm to protect the wireless communications against eavesdropping attacks by exploiting(More)
The purpose of this letter is to propose a novel carrier frequency offset (CFO) estimator in the presence of DC offset (DCO), based on the pilot's periodicity. The new CFO estimator can achieve satisfactory performance at low complexity, irrespective of the DCO presence. The superiority of the proposed estimator is verified by the subsequent analysis and(More)
A novel non-linear chirp spread spectrum modulation (CSSM) is introduced for binary data transmission in a multi-user (MU) environment. Two subclasses of non-linear signals namely quadratic (Q-CSSM) and exponential (E-CSSM) modulations are described and their properties are given. The chirp rates in these modulations are varied as a function of user in an(More)
The ever-increasing demand for precious radio spectrum along with the inefficient usage of licensed band has led to the advent of the cognitive radio (CR) technology, which aims to provide opportunistic spectrum usage to unlicensed users and thus lead to the co-existence and interference control problem among heterogeneous systems. In this paper, an(More)
This paper considers the classification of digital modulation schemes in the presence of multipath fading channels and additive noise. A novel modulation recognition approach is proposed based on Gaussian Mixture Models (GMM). Our basic procedure involves parameter estimation using GMM to set up an offline database and then to classify the received signal(More)