The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
The base station (BS) density configuration is a key factor to improve energy efficiency (EE) performances. In this paper, BS density configurations for achieving the optimal EE performance in two-tier cellular networks are analyzed, where the Poisson point process (PPP) is used to model the BS spatial distribution. To make the EE performances trackable and analyzable, the BS density optimization...
The heterogeneous cloud radio access networks (H-CRANs) are presented in this paper as a promising new paradigm for future heterogeneous converged networks. To maintain low traffic queue congestion and make the sum utility of average throughput arbitrarily close to the optimum, the dynamic optimization problem of traffic admission control, heterogeneous processing node (HPN)/remote radio head (RRH)...
The cloud radio access network (C-RAN) is an emerging network architecture that holds the promise of coping with the explosive growth of mobile wireless data. In this paper, by considering the stochastic traffic arrivals and time-varying channel conditions, we address the stochastic optimization of joint remote radio head (RRH) activation and linear beamforming to maintain delay performance and minimize...
Characterizing user access methods in heterogeneous cloud radio access networks (H-CRANs)is critical for performance optimization. Different from the user access in cloud radio access networks, the inter-tier interference from macro base station has a great impact on user access in H-CRANs. In this paper, after considering the inter-tier interference, the ergodic rates of downlink H- CRANs for two...
This paper investigates the problem of resource and power allocation in device-to-device (D2D) underlays given a specific secrecy rate constraint. The objective is to optimize the pairing of D2D links with cellular user equipment (CUE) uplink channel resources, and to allocate their respective powers to combat against eavesdroppers for secrecy rate improvement. The proposed method first determines...
To realize an efficient utilization of harvested energy and improve throughput with the help of a battery, a harvest-use-store power splitting (PS) relaying strategy with distributed beamforming is proposed for the wireless-powered multi-relay scenario in this paper. To this end, harvested energy via PS can be accumulated and stored for future usage, which affects throughput at subsequent time slots...
Todays wireless networks are mostly dominated by multimedia content, which poses much pressure on the macrocell networks. In such a case, underlaid small cells deployment is considered promising to off-load the traffic from the overburdened macrocell network and meet the applications' quality of service (QoS). However, the interference management among dense deployment of small cells remains a technical...
This paper investigates the effect of channel estimation errors on the capacity of full-duplex amplify-and-forward relay networks. We first derive the lower bound of the capacity in the presence of channel estimation errors and residual self-interference due to full-duplex relaying. Accordingly, the optimal power allocation schemes in maximizing the capacity with joint power constraints are proposed...
Small cell networks (SCNs) have been presented as an efficient way to improve the capacity of wireless networks. However, dense deployment of small cell base stations (SBSs) can cause severe intra-tier interference which prevents the system from achieving high spectrum efficiency. Therefore, the investigation on interference coordination in SCNs is essential. In this paper, we formulate the interference...
The speed of user equipment (UE) is significant in improving the performance of orthogonal frequency division multiplexing (OFDM) systems. Estimating the speed can help in adaptively allocating resources to users, reducing call drop rate in handoff, selecting the optimal radiation pattern, etc. The Doppler spread caused by the relative movement between transmitter and receiver can be utilized to estimate...
Nested lattice code is a practical technique to approach the Shannon capacity upper bound. However, the performance of compute-and-forward (CF) relaying is blocked by the channel output residuals that the decoding process of nested lattice codeword cannot remove completely. In this paper, an interference truncation scheme is designed for CF relaying in multiple access channels to minimize the channel...
The deployment of small cell base stations (SCBSs) overlaid on existing macro cellular networks can potentially improve the coverage and capacity of cellular wireless systems. However, a massive deployment of SCBSs also leads to an undesirable increase in energy consumption and severe intratier and inter-tier interference. In this paper, the joint design of discontinuous transmission (DTX) and power...
Spectrum sharing for cognitive two-way relaying is considered in this paper. A secondary relay is used to assist two-way communications between two primary users, and as a return, the secondary relay is allowed to transmit its own secondary signal by using some of the licensed primary spectrum. Three different spectrum sharing strategies are studied in this paper. In the baseline superposition coding...
Small cells have recently emerged as an effective technology in meeting the increased demand for cellular network capacity. Cloud radio access networks (C-RANs), composed of baseband units (BBU), remote radio heads (RRH) and the optical transport network, have been introduced to harness the capacity benefits of small cells at reduced capital and operational expenses. However, dense deployment of RRHs...
Considering environment protection and cost-efficiency, cloud radio access network (C-RAN) has received considerable attention. In C-RAN, centralized baseband units (BBUs) are composed of high-capacity processing units and realtime virtualization, so the BBU can control resource allocation according to the distribution of users, which will keep the system work with the highest bandwidth efficiency...
Driven by the surging mobile data traffic demands, the cloud radio access network (Cloud-RAN) of small cells has attracted intense interest in both academia and industry. In practice, the capacity-limited backhaul may eventually restrict the performance potential of cooperative multipoint transmission in Cloud-RAN. In this paper, we consider the delay-aware cooperative beamforming control for delay-sensitive...
Cognitive two-way relaying is studied in this paper. A secondary relay is used to assist bidirectional communication between a pair of primary users. As a return, the secondary relay is allowed to transmit its own secondary signal on the licensed primary spectrum. For this purpose, superposition coding is employed at the relay to superimpose the secondary signal on the primary signals. Three typical...
In this paper, we study a cognitive two-way relay network in which orthogonal frequency division multiplexing (OFDM) technique is adopted within the secondary system and a pair of secondary source nodes communicate with each other through a relay node by using amplify-and-forward two-way relaying strategy. We propose an optimal power allocation scheme to maximize the smaller data rate of the secondary...
Energy harvesting is necessary to make the wireless network self-sustaining and self-organizing regardless of the traditional power grid. How to allocate the limited radio resources in the energy harvesting wireless network is a challenging work. This paper focuses on optimizing the time and power related resources in the multi-cell scenario to maximize the throughput constraining of the changeable...
Device-to-Device (D2D) technology provides a potential way to improve cellular network throughputs. However, severe interference is introduced with universal frequency reuse, which significantly degrades the network performance. In this paper, we investigate distributed power control strategies in a D2D underlaid cellular network. An enhanced single-leader-multiple-followers Stackelberg game model...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.