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 device-to-device (D2D) communication has become one of the most promising methods for alleviating the deficiency of wireless spectrum. In spite of the potential gains brought by activating D2D communications, the problem of severe interference between cellular and D2D users cannot be ignored. In this paper, we introduce the power-control scheme based on interference limited area (ILA) for alleviating...
Non-orthogonal multiple access (NOMA) is a promising multiple access scheme for next generation wireless networks. This paper investigates the sum rate maximization problem for NOMA system over a frequency selective fading channel with its users being paired according to their channel powers. A hierarchical power allocation process is proposed, whereby the users are divided into two groups such that...
Short-term traffic flow forecasting has been a crucial component in the area of intelligent transportation systems (ITS), which plays a significant role in operating traffic management systems and dynamic traffic assignment effectively as well as proactively. In this paper, a novel short-term traffic flow prediction method called Ensemble Real-time Sequential Extreme Learning Machine (ERS-ELM) with...
In this paper, we propose an indoor localization system employing ordered sequence of access points (APs) based on received signal strength (RSS). Unlike existing indoor localization systems, our approach does not require any time-consuming and laborious site survey phase to characterize the radio signals in the environment. To be precise, we construct the fingerprint map by cutting the layouts of...
The selection of nonzero taps for sparse linear equalizer under the criterion of minimum mean square error (MMSE) is investigated. In some applications such as underwater acoustic communications, the computational resource in terms of the number of nonzero channel taps is given in existing channel equalizers. In this context, the joint determination of positions and weights of nonzero taps of sparse...
This paper proposes soft bit estimation methods for high-order amplitude and phase shift keying (APSK) schemes defined in the DVB-S2X system. The proposed method first maps the detected symbol to a limited range in a recursive manner, so that the search ranges to find a symbol with the minimum distances can be greatly reduced. Subsequently, amplitude of the detected symbol automatically determines...
Internet of things (IoT) is widely expected to be an important scenario in the fifth generation (5G) wireless network. Major challenges of IoT include the low cost of devices, low energy consumption, low latency and the ability to support a large number of simultaneous connections. In this article, a new type of non-orthogonal multiple access scheme called multi-user shared access (MUSA) is proposed...
This paper presents a 60 GHz CPW-fed patch antenna on multilayer LTCC- and LCP-based materials with new and compact AMC. The proposed antenna structure consists of top three layers of antenna and bottom three layers of AMC ground plane. First, a new and compact three- layer AMC is designed on both LTCC- and LCP-based substrates. The designed AMC is more compact and provides 37.5% higher in-phase bandwidth...
Rotten bridges and highways, the raised population density and car penetration as well as daily and long-time roadworks are just a few reasons of the modern transportation challenge: the steadily increase of traffic density. This unavoidable trend also comes along with the well-known negative effects such as traffic jams, car accidents and CO2 emissions. Hence, current research approaches aim on generally...
By providing substantial gains in terms of both spectral and energy-efficiency, Massive MIMO is expected to be the promising enabler for the fifth generation (5G) communications. However the performance of massive MIMO is greatly affected by pilot contamination due to the insufficiency of pilot sequences. To overcome this, we propose a linear programming based pilot allocation with the purpose of...
Heterogeneous network is a novel network architecture proposed in Long-Term-Evolution (LTE) which can highly increase the capacity and coverage compared with the conventional networks. However, in order to provide the best possible services, appropriate resource management must be applied. In this paper, we consider the joint optimization of subcarrier and power allocation for downlink transmission...
We propose a novel spatial modulation (SM) scheme, which is a joint of two index modulation schemes. One is the M-ary spatial shift-keying (MSSK) modulation operated in the space domain, while the other one is the M-ary orthogonal shift keying (MOSK) modulation, which usually requires more bandwidth to implement, when its modulation level increases. As both MSSK and MOSK belong to the energy-efficient...
It is generally recognized that efficient multiplexing of users with highly diverse requirements needs a flexible frame structure. For a new 5th generation mobile networks (5G) air interface, the hybrid automatic repeat request (HARQ) solution should also be revised to harvest all possible performance benefits that can be obtained with a flexible frame structure. In this paper, we outline a number...
As a promising downlink multiple access scheme for further cellular enhancements toward 5G, non- orthogonal multiple access (NOMA) improves both cell average and cell-edge user throughput compared to orthogonal multiple access (OMA). Our previous work showed that NOMA can improve system performance compared with OMA even when combined with multiple- input multiple-output (MIMO). However, for NOMA...
For time division duplex systems with increased bandwidth in 5G, the concept of self-contained transmission has been proposed. Aiming at reduced latency and more flexible resource allocation, this concept involves frequent uplink and downlink switching and relatively short transmission in both directions. In this work, we consider single OFDM symbol transmission within self-contained transmission...
Energy-efficient transmission is a hot topic in wireless communication due to the conflict between the booming traffic demand and the limited energy resource. In this paper, an algorithm for downlink power allocation combined with user association is studied to improve the energy efficiency of a software defined cellular network. The problem mentioned above is non- convex but can be solved with QPSO,...
This paper is concerned with the coded orthogonal frequency division multiplexing (OFDM) with index modulation (IM) for highly mobile wireless communication based on block Markov superposition transmission (BMST). In the OFDM-IM scheme, the information bits are not only mapped into the conventional two-dimensional signal points but also into the indices of the subcarriers. For the coded IM system,...
In this paper, codebook design for massive MIMO systems with 32/64Tx transmit branches is investigated. Using the same parameterized codebook framework of LTE Rel-13 for 16Tx, 32/64Tx codebooks are discussed and evaluated through system level simulations. In addition, to deal with the larger feedback overhead, three codebook sub-sampling methods are discussed. These methods aim to achieve a tradeoff...
Universal Filtered Orthogonal Frequency Division Multiplexing (UF-OFDM) is considered as a promising 5G waveform candidate. It requires a relatively simple transceiver structure, while achieving much better spectral properties compared to CP-OFDM. During the early deployment of 5G systems, many frequency bands will still be occupied by 4G systems, using the legacy CP-OFDM waveform. The main focus...
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.