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We investigate the error performance of both multilevel polarization shift keying (MPOLSK) and spatial modulation based MPOLSK (SM-MPOLSK) architectures for multiple-input-multiple-output (MIMO) communication over atmospheric turbulence channels. We first show that bit groups corresponding to each signalling dimension of these architectures are affected unequally from the turbulence induced scintillation...
We investigate the error performance of both multilevel polarization shift keying (MPOLSK) and spatial modulation based MPOLSK (SM-MPOLSK) architectures for multiple-input-multiple-output (MIMO) communication over atmospheric turbulence channels. We first show that bit groups corresponding to each signalling dimension of these architectures are affected unequally from the turbulence induced scintillation...
In conventional space shift keying (SSK) and generalized SSK (GSSK), the symbols are transmitted only by the active antennas indices, while the inactive antennas remain unexploited; this limits the spectral efficiency. In order to combat this limitation, we propose a direct-code for SSK (DC-SSK) modulation technique. In DC-SSK, the transmitter is allowed to use 0,1,…, Nt antennas for each symbol,...
Long Term Evolution (LTE) developed by Third Generation Partnership Project (3GPP), is the access part of the Evolved Packet System (EPS). LTE physical layer is based on Orthogonal Frequency Division Multiple Access (OFDMA) with Quadrature Amplitude Modulation (QAM). Although there has been lots of enhancements in the LTE physical layer, yet higher order modulation schemes were not introduced in the...
Fed up of slow speed networks, sharing your hotspot, then here's a solution which involves the use of LEDs at your place because of which speed of the networks get increased with a secured connection. Light has been a source of life and many more stuff, so here comes a new concept Li-Fi, as it is dubbed i.e., Light Fidelity. Chairperson of mobile communication at University of Edinburgh, Herald Haas,...
Due to the exploding evolution of wireless communication systems, energy efficiency (EE) becomes the concern of many researches. In this context, we examine this metric into multiband orthogonal frequency division multiplexing ultra wideband (MB-OFDM UWB) systems. Indeed, the focus is about investigating a cross-layer design based on the joint combination between data link layer through the hybrid...
In this paper, we present a throughput optimized cross-layer design for multiple-input multiple-output (MIMO) wireless systems. The proposed design efficiently combines power control (PC), adaptive modulation and coding (AMC) and MIMO technology at the physical layer, with an automatic repeat request (ARQ) protocol at the data-link layer. Both basic ARQ and type-I hybrid ARQ are considered. More specifically,...
We investigate the application of network coding to file transfers from a single source to multiple destinations in a two-hop ad hoc relay network that consists of half-duplex packet radios. Our network-coded file distribution techniques make simultaneous use of a pair of relay nodes. All transmissions by the source and the relay nodes employ packet-by-packet adaptive modulation and channel coding...
This paper gives an insight into IEEE 802.11ac by analysing its performance in terms of system throughput taking into consideration the key features of MAC and PHY layers. Throughput at MAC layer is calculated from transmission probability, contention window and transmission stage. Likewise, the new critical attributes of 802.11ac PHY (i.e. modulation and coding schemes, spatial streams, and channel...
One of the major factors which degrades the Free Space Optics (FSO) link performance is the atmospheric turbulence. Turbulence manifests in increased Bit Error Rate (BER) leading to degradation in the link performance. Adaptive Coding and Modulation (ACM) technique is used to mitigate this effect. This technique is an adaptive transmission scheme wherein transmission parameters such as modulation...
This paper is concerned with an attractive multi-antenna multi-carrier modulation scheme, termed as {\em generalized space-frequency index modulation (GSFIM)}, which is a promising modulation scheme for next generation wireless systems. GSFIM uses both spatial domain and frequency domain to encode bits through {\em indexing}. In GSFIM, information bits are mapped through antenna indexing in the spatial...
To realize the autonomous adjustment function of the system parameters of the anti-jamming decision engine, a kind of swarm intelligence optimization algorithm- binary artificial bee colony (BABC) algorithm was used for reference. Decision method of communication anti- jamming based on binary artificial bee colony was proposed. In order to realize the autonomous choice of communication parameters,...
Recently, Digital Video Broadcasting (DVB) has evolved to improve the spectrum efficiency of current multimedia communications. This paper summarizes the main features and presents the error performance for the second generation of satellite DVB (DVB-S2) utilizing an upgraded MATLAB simulation model. In addition, the paper makes a validation of the developed simulation model by comparing between model...
With the growing popularity of mobile applications such as voice over IP (VoIP) and real-time conversational video, and due to the scarcity of the available radio spectrum, increasing the spectral efficiency of wireless systems under quality of service (QoS) constraints becomes increasingly important. Accordingly, in this paper we investigate the maximum achievable rate of incremental redundancy type...
With the increase in camera resolution or usage of SAR payload in remote sensing satellite, demand for high data rate transmission has increased in a given bandwidth. This has also forced to use higher modulation like 8 PSK over QPSK to accommodate higher data rate in the same bandwidth. A typical usage is 1.2Gbps data rate transmission scheme using 8PSK dual polarization in x-Band, having bandwidth...
Continuous phase modulation (CPM) is a family of bandwidth-efficient signaling schemes with memory. In this paper we introduce a simulation-based method to compute a lower bound, namely the dependence testing (DT) bound, on the maximum achievable rate of general CPM schemes under finite blocklength, probability of error, and equiprobable input distribution constraints. The proposed method utilizes...
Spectral efficiency and energy efficiency are fundamental trade-off in wireless communications. Spectral efficiency (SE), defined as the average data rate per unit bandwidth, quantifies how efficiently the available spectrum is utilized. Energy efficiency (EE), defined as the successful transmitted information bits per unit energy from transmitter to receiver, quantifies how efficiently the energy...
Direct application of spatial modulation (SM) for orthogonal frequency division multiplexing (OFDM) systems does not realize the inherent frequency diversity gain since information symbols are not spread over independently-faded subcarriers. This paper investigates a new transmission scheme that employs spatial modulation (SM) for each group of subcarriers in OFDM. Specifically, OFDM symbols in each...
Combining the Alamouti space-time block code with spatial modulation (STBC-SM) was recently demonstrated as an effective way to increase the spectral efficiency and achieve a transmit diversity order of two as compared to the original spatial modulation (SM). This paper investigates a new transmission scheme that is based on a high-rate space-time block code rather than the Alamouti STBC. A simplified...
A new transmission scheme is designed to maximize average spectral efficiency in a MIMO link considering instantaneous bit error rate (BER) and total power constraints. Discrete link adaptation using adaptive modulation and coding (AMC) is utilized to combat multipath fading which is implementable in practical systems. ZF receiver is employed by which MIMO channel becomes equivalent to several parallel...
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