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Performing and evaluating Call Trace (CT) or also called Minimization of Drive Test (MDT) measurements entails additional expenses to the operator as well as to the users. However, by using location specific network data obtained from the measurements as additional information for self-organization procedures, we expect these procedures to perform essentially better since they can take their decisions...
We consider a heterogeneous cellular network (HetNet) where a macrocell tier with a large antenna array base station (BS) is overlaid with a dense tier of small cells (SCs). We investigate the potential benefits of incorporating a massive MIMO BS in a TDD-based HetNet and we provide analytical expressions for the coverage probability and the area spectral efficiency using stochastic geometry. The...
Indoor downlink communication contributes to a large part of the data traffic generated in today's world. Enormous high data rate supporting devices are entering todays market. They demand for high rate wireless indoor coverage for their uninterrupted service. The main challenge lies in working with the existing wireless technologies while providing a future proof centralized optical fiber indoor...
This paper presents detailed results of 11 GHz band outdoor transmission experiments employing 8 × 16 MIMO-OFDM for 10 Gbps super high bit rate mobile communications. Super high bit rate mobile communications have been studied for future mobile communications, and to verify the feasibility, outdoor transmission experiments were performed. A mobile station (MS) with 8 transmitter antennas traveled...
This paper proposes a new codebook structure called Kronecker-product based codebook (KPC), where each codeword is the Kronecker product of two oversampled DFT codewords in both the horizontal and vertical domains. The KPC is especially suitable for the three-dimensional (3D) multiuser multi-input multi-output (MU-MIMO) systems. Besides, channel state information feedback based on the best companion...
Spatial spectrum sharing with MIMO cognitive radio is efficient and attractive for wireless systems with limited communication resources. MIMO cognitive radio is a kind of cognitive radios using MIMO beamforming techniques to avoid interference to other nodes. There are many theoretical works on this topic but validation of the algorithm on real hardware has not been realized. Most of these works...
Cellular mobile communication systems reuse the same frequency channel in geographically distant areas to improve the spectrum efficiency. However, co-channel interference among cells remains a critical issue. Mitigating co-channel interference leads to a further improvement in spectrum efficiency. To reduce the co-channel interference we proposed vertical plane beam control using precoding and cooperative...
Indoor coverage is essential to the mobile user experience, because the signal power from the remote macro base stations is seriously weakened after penetrating the walls. Traditional indoor coverage system is a good solution but it can not be deployed in all the buildings. In order to enhance the received signal power inside the building, a relay can be used in a long term evolution (LTE) system...
The impact and information-theoretic limits of infrastructure support with rate-limited wired links are analyzed in hybrid ad hoc networks, where multi-antenna base stations (BSs) are deployed and the rate of each BS-to-BS link scales at an arbitrary rate relative to the number of randomly located wireless nodes. For the operating regimes with respect to the number of BSs and the number of antennas...
Video transmission over long term evolution (LTE) networks is studied. The use of distributed antenna systems (DAS) is proposed to enhance the video quality of experience (QoE). Real time video streaming over both the uplink (UL) and downlink (DL) directions is investigated. LTE dynamic resource allocation is taken into account, and several types of DAS deployments are analyzed and compared. Simulation...
In this paper a switch-stay model is proposed for spectrum access by a secondary user in the presence of a primary user, which considers the impact of spectrum handoff delay. This model is then studied to balance the trade-off between the secondary user's energy efficiency and transmission reliability in light of the probability of collision, throughput and delay constraints. Bounds on the probability...
Small cell networks have recently been proposed as an important evolution path for the next-generation cellular networks. While such approach has the potential of meeting the growing network throughput requirement, the energy efficiency of small cell networks is of great concern as the base station (BS) density will be significantly increased. The objective of this paper is to analyze the energy efficiency...
In this paper, we investigate the coexistence problem between the 802.22 and the 802.11af systems in the TV White Spaces (TVWS). We focus on the design of a co-channel coexistence scheme for the 802.22 customer-premises equipments (CPE) and the 802.11af systems. 802.22 and 802.11af are two typical standards envisioned to be widely adopted in the future. However, these two standards are heterogeneous...
The inter-cell interference problem is a key challenge for the planning of OFDMA-based cellular networks. This paper shows the possible gains that can be obtained by employing a static Inter-Cell Interference Coordination (ICIC) scheme in the downlink. A simplified simulation-based capacity analysis study is performed investigating the correlation between system capacity and the distributions of power...
Heterogeneous network (HetNet) has been studied earlier in the context of LTE. But lately, there are also some discussions about HetNet in HSPA. Cross-tier interference (CTI) is an annoying issue to be investigated in the co-channel HSPA HetNet (CHH) scenario. In this paper, we will focus on the downlink CTI problem in CHH and propose a solution to mitigate it. Our scheme involves the macro muting...
The aim of this paper is to examine the benefit of rapid dynamic antenna tilting on a WCDMA cellular network, where dynamic antenna tilting is applied as either a SON implementation or a MIMO implementation. The potential network performance improvement of this technique is evaluated using a dynamic WCDMA/LTE simulator and the results presented suggest that downlink performance gains of up to 89%...
Cellular structures are to be enhanced by heterogeneous deployments. One type of such deployments is to add outdoor pico evolved NodeBs (PeNBs), formulating a hierarchical cell structure with macro eNBs (MeNBs). The cell selection in such system is facing challenges, including problems of coverage and cross interference. One method is called cell range expansion (RE), typically in which a common fixed...
This paper presents MIMO/CON, a PHY/MAC cross-layer design for multiuser MIMO wireless networks that delivers throughput scalable to many users. MIMO/CON supports concurrent channel access from uncoordinated and loosely synchronized users. This new capability allows a multi-antenna MIMO access point (AP) to fully realize its MIMO capacity gain. MIMO/CON draws insight from compressive sensing to carry...
The DockingAssist system is a centralised, cost-effective, real-time navigation system that provides the necessary centimetre positioning and speed accuracy to ensure efficient and safe manoeuvring within a entire port area, thereby enhancing vessel trajectory and providing constant monitoring of moored/docked vessels. By reducing transit, this system will result in improved port traffic management...
In this paper, we study the multiplexing throughputs of open- and closed-loop multiple-input multiple-output (MIMO) systems with fixed modulation and coding (i.e., fixed maximum data rate). For the open-loop case, we assume the simplest linear decoder, i.e., zero forcing (ZF). For the closed-loop case, we assume singular value decomposition (SVD). Using the threshold receiver model (accounting for...
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