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.
In the near future some of mobile communication prime objectives need to be improved, including increased capacity, higher data rate, low latency, and better quality of service. To respond to these growing demands, a modification should be done at the physical layer in terms of waveforms adopted. Flexible waveforms have been proposed to meet the challenges faced in current generation systems such...
Recent advances in chaotic communications have paved the way for the implementation of matched filter based receivers to detect chaotic signals generated by hybrid-chaotic oscillators. These oscillators offer an exact analytic solution given their fixed basis function. This paper extends the hybrid-chaotic oscillator concept and presents a novel hybrid-chaotic oscillator for multilevel chaotic modulation...
In this work, we present an acoustic modem system that transmits data using multicarrier modulation through the air interface. The choice for this type of modulation over single carrier modulation arises from the need for an efficient use of the limited bandwidth, the minimization of multipath effects as frequency fading. The system transmits data using sound waves resting on the output and input...
The demand for more data with an optimal use of spectrum in next generation mobile networks is driving researchers to invent a new physical waveforms, Filter Bank MultiCarrier (FBMC) and Filtered-Orthogonal Frequency Division Multiplexing (F-OFDM) are among the potential modulation schemes for the next generation. In this paper we present a comparative analysis of FBMC scheme after a quick review...
Power Line Communication (PLC) channel is a very challenging environment, this is due to the fact that severe impairments adhering this medium. A more realistic and accurate noise model based symmetric alpha-stable distribution (SαS) is considered in this paper to better fit the properties of real noise inherent in power grid system. In this paper we study the impact of the degree of impulsiveness...
Due to the low out-of-band emission and robustness against asynchronous transmissions, generalized frequency division multiplexing (GFDM) has potential to be a new modulation scheme for the foreseeable applications. In this paper, a novel precoding scheme with tunable band sizes is proposed for GFDM systems. The precoder and equalizer are jointly designed aiming at minimizing the system total mean...
The emerging market of the Internet of Things (IoT) requires new energy-efficient and low-complexity Multiple-Input-Multiple-Output (MIMO-) aided radio access technologies. This trend will have a profound impact on both the theory and practice of future communication networks, which will not be purely optimized for approaching the attainable capacity anymore, but will explicitly include the energy...
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...
Chirp slope keying (CSK) modulation based on linear frequency modulation signal (LFM) and hyperbolic frequency modulation signal (HFM) combined with passive time reversal (PTR) for mobile underwater acoustic communication is proposed in this paper. For CSK modulation, the carriers are LFM and HFM signals, and the bit information is represented by different signals. A PTR processor is designed at the...
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...
The LoRa technology has emerged as an interesting solution for low power, long range loT applications by proposing multiple “degrees of freedom” at the physical layer. This flexibility provides either a long range at the cost of a lower data rate or higher throughput at the cost of low sensitivity, so a shorter range. In this paper, we analyze the flexibility of LoRa and propose various strategies...
Recently, automatic modulation classification techniques using convolutional neural networks on raw IQ samples have been investigated and show promise when compared to more traditional likelihood-based or feature-based techniques. While likelihood-based and feature-based techniques are effective, making classification decisions directly on the raw IQ samples allows for reduced system complexity and...
In the conventional directional modulation (DM) system without relay aiding, when the eavesdropper locates within the main-beam of the desired direction, it can intercept the confidential message from source Alice. In this paper, we propose a strategy to enhance physical-layer security of direction modulation in wireless transmission with the help of multi-relay cooperation. In this scenario, the...
This work is motivated by the need for the fundamental increase of spectral efficiency with the transmissions on the Transmission Control Protocol and the Internet Protocol (TCP/IP). To emphasize the work in physical layer, we define a bit-unit (BU) that is conceptually similar to an IP packet containing sufficient information for its destination node to identify the address and interpret the contents...
NarrowBand Waveforms (NBWF) are often used in VHF or UHF tactical communications. For these kinds of waveforms, low latency and robust data rates result in short codeword lengths that are challenging in terms of channel coding. Usually, serially concatenated convolutional code and continuous phase modulation (CC-CPM) schemes are considered in the context of NBWF. When evaluating the achievable rates,...
The High Performance Waveform (HPW) was developed before parallel concatenated codes (PCCC) and serial concatenated codes (SCCC) were in wide use and so it makes sense to take advantage of the advancements in communication theory and processor computation speed that have taken place since its inception. In its current form, HPW transmits a Raised-Cosine Continuous Phase Modulation (1RC CPM) modulation...
The SATURN Enhanced Data Rate (SEDR) waveform has been introduced by Line Of Sight (LOS) NATO standardization group as the new coalition standard for military airborne Ultra High Frequency (UHF) communications. However, the current design of its physical layer presents several shortcomings since it is a straightforward transposition of SATURN definition to wider channels. Indeed, new generation wide-band...
Most practical visible light communication (VLC) systems being currently deployed with image sensor receivers use intensity modulation and direct detection scheme for outdoor and indoor applications. A number of modulation and coding techniques that are used for image sensor-based VLC systems are presented.
In this paper, an enhanced scheme of Index Modulation for Orthogonal Frequency Division Multiplexing (IM-OFDM), called Repeated IM-OFDM with Diversity Reception (ReIM-OFDM) is proposed. ReIM-OFDM achieves performance improvement over the convetional IM-OFDM at the same spectral efficiency by providing additional space and frequency diversity. Similar to IM-OFDM, the proposed ReIM-OFDM also activates...
ISDB-T defines the so-called Broadcast Transport Stream, an MPEG transport stream adapted to carry hierarchical information. This BTS is created in the transmission side, but it has to be perfectly recovered in reception. To that end there is an algorithm defined in the standard which we found not clear regarding the implementation. We also found the bibliography regarding this algorithm was poor...
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.