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A non-orthogonal multicarrier signal, termed spectrally efficient frequency division multiplexing (SEFDM), is investigated in this work. It improves spectral efficiency by compressing sub-carrier spacing below the symbol rate at the cost of self-created inter carrier interference (ICI). Sphere decoding (SD) is an efficient method to recover signals approaching maximum likelihood (ML) performance....
Electromagnetic interference can cause severe performance degradation on wireless communication systems. In modern military platforms there are many closely located electronic systems, which could potentially cause interference. The performance degradation is largely affected by the characteristics of the interference. With knowledge of the actual interference environment, radio receivers can be adapted...
Dynamic spectrum access (DSA) has been envisioned to become the key to solving worldwide spectrum shortage. However, the open nature of wireless medium brings severe threats to the DSA system resulting from unauthorized access. Specifically, unauthorized secondary user (SU) utilizes the licensed spectrum by faking/replaying the spectrum permit, which will not only introduce severe interference to...
Dynamic Spectrum Access (DSA) has been proposed to increase the spectrum utilization efficiency and to solve the spectrum scarcity problem. However, due to the spectrum sharing and opportunistic access nature of the DSA networks, they are more vulnerable to security threats like jammers. In this paper, we propose an anti-jamming technique in which the secondary network coordinator groups the secondary...
4G Long Term Evolution (LTE) mobile system adopts Adaptive Modulation and Coding (AMC) as a link adaption mechanism that is based on the User Equipment (UE) periodically reporting channel condition summarised through Channel Quality Indicator (CQI) which, in turn, is based on Signal-to-Interference-plus-Noise Ratio (SINR) and Reference Signal Received Power (RSRP). Although CQI has a predominant role...
In next generation communication systems high data rate, and higher transmission capacity through wireless channel are important for researchers. Filter bank based multicarrier (FBMC) modulation with offset quadrature amplitude modulation (OQAM) makes researchers interested due to its advantages over orthogonal frequency division multiplexing (OFDM). The paper indicates that OFDM, FBMC-QAM, multiple-input...
In this paper, a joint cross-layer design of adaptive modulation and coding (AMC) and cooperative automatic repeat request (C-ARQ) scheme is proposed for a secondary user in a shared-spectrum environment. First, based on the statistical descriptions of the channel, closed-form expressions of the average spectral efficiency (SE) and the average packet loss rate (PLR) are presented. Then, the cross-layer...
We introduce a novel concept for anomalous surface-wave (SW) guiding on penetrable omega-bianisotropic metasurfaces, designed to guide a pair of SWs on each of their facets. The eigenmode is thus a quadruple of SWs, exchanging power via the metasurface while propagating along it. Full-wave simulations verify that these eigenmodes can be efficiently excited by a localized source, and the SW interference...
Although the base station processing and the majority of the protocols of the wireless systems are standardized by 3GPP, the receiver architecture and implementation remain vendor-dependent. The receiver design should fulfill computational efficiency requirements, and be evaluated in practical simulators or emulators that are compliant with real-world wireless standards. In this paper, we provide...
As in-line interference between geostationary(GEO) and Non-Geostationary(NGEO) systems is becoming more and more serious. We propose an efficient utilisation of the adaptive modulation and coding (AMC) scheme for spectral coexistence of GEO and NGEO satellites to mitigate in-line interference. Results of Simulation show that the proposed scheme can improve the performance of the NGEO system in comparison...
Optical coherence tomography (OCT) is an emerging optical technology that is capable of non-invasive cross-sectional imaging of biological tissues at high-speed, highresolution, and high sensitivity. OCT has been proven to be a potential tool for medical diagnostics and biomedical researches. One important parameter that governs an imaging depth of spectrometer-based spectral domain OCT (SD-OCT) is...
The growing requirements of mobile broad band services like MIMO, combined with OFDM involved in 4g wireless networks were met by Long Term Evolution (LTE).OFDM is used in communication systems to provide high data rates, and is more immune to intercarrier interference, and intersymbol interference. OFDM has become the core of LTE system. In this paper the performance of the system is evaluated interms...
In recent years, power line communication technology has seen a rapid development. However, due to the unsteadiness of the power line channels, the communication attenuation and bit error rate is still a big problem. Based on the previous research of spread spectrum communication and orthogonal frequency division multiplexing (OFDM), in this paper, we studies the method to eliminate attenuation using...
Ambient backscatter is a promising solution for future Internet of Things (IoT) composed of massive low-power wireless devices without external power sources. It is challenging to accommodate these devices with high throughput and long range because of the low efficiency inherent in ambient backscatter. To tackle the challenging issue, we propose an optimum modulation and coding scheme (MCS) for ambient...
Although Orthogonal Frequency Division Multiplexing (OFDM) technology has been widely used in LTE and other systems, the problem of large band leakage caused by the Doppler effect restricts the further improvement of performance when the user moves at high speed. The Filter bank based multi-carrier (FBMC) technology is one of the effective techniques which could replace OFDM in 5G communication systems...
Pattern Division Multiple Access (PDMA) is a novel non-orthogonal multiple access scheme proposed to meet the demand of massive connection in the future 5G communications. PDMA is based on the joint design of transmitter and receiver. The multiuser signals are superposed on the multiple signal domains based on different characteristic patterns at the transmitter side, and the successive interference...
5G systems aim to achieve extremely high data rates, low end-to-end latency and ultra-low power consumption. Recently, there has been considerable interest in the design of 5G physical layer waveforms. One important candidate is Generalised Frequency Division Multiplexing (GFDM). In order to evaluate its performance and features, system- level studies should be undertaken in a range of scenarios....
This paper aims to evaluate the system level performance of the newly proposed non-orthogonal multiple access scheme sparse code multiple access (SCMA) with uplink grant-free transmissions for 5G massive machine-type communication (mMTC) scenario. The challenge lies in the modeling and abstraction of physical layer actions as the link-to-system interface, including the features of overloading, grant-free...
Non-Orthogonal Multiple Access (NOMA) has been suggested as one of the technologies to be implemented in the fifth generation - 5G - mobile networks. NOMA helps increasing the capacity by offering a more effective use of the available resources, but it also intentionally introduces interference in the transmitted signal. This means that higher signal-to-interference-plus-noise ratio (SINR) values...
Hydrogen sulfide (H2S) is a highly toxic gas that can be frequently found in the vicinity of industrial sites such as petroleum refineries, natural gas plants, or waste water treatment facilities. Its open-path detection with sensitivities at single ppm (parts-per-million) levels is critical for safety reasons. Laser-based H2S sensing typically relies on a quartz-enhanced photo-acoustic spectroscopy...
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