Today high bandwidth, capacity and responsiveness are very important in wireless networks. This has led to increased research in the areas of frequency diversity, wideband technologies and cognitive radios. SSCH [1] proposes to improve capacity by leveraging frequency diversity by having nodes communicate on different channels of the available spectrum. The idea of SWIFT [2] is to weave togethe...

For ground-to-air and air-to-air communications, clouds form a main element of the communication channel. In wireless optical communications, clouds induce temporal and spatial dispersion, causing power loss and bandwidth constraints; critical parameters for reliable communication system design. In this paper, we focus on the temporal dispersion induced by the clouds, and provide a statistical ...

In recent years, Multi-Input Multi-Output (MIMO) communications are introduced as an emerging technology to offer significant promise for high data rates and mobility required by the next generation wireless communication systems. Using multiple transmit as well as receive antennas, a MIMO system exploits spatial diversity, higher data rate, greater coverage and improved link robustness without...

Abstract We present a systematic study of quantum receivers and modulation methods enabling resource efficient quantum-enhanced optical communication. introduce quantum-inspired schemes that theoretically yield better efficiency than legacy protocols. Experimentally, we demonstrate below the shot-noise limit symbol error rates for M ≤ 16 communication alphabets using software-configurable time-...

Distributed antennas can be used to provide a mean to combat fading with a similar flavor as that of space diversity. This kind of reliability obtained by the creation of virtual antennas is referred to as cooperative diversity because the terminals share their resources to get the information across to the destination. Such schemes have attracted significant attention recently, and a variety o...

This study evaluates the impact of underwater ambient noise using seven real noise samples; Dolphin, Rain, Ferry, Sonar, Bubbles, Lightning, and Outboard Motor in three frequency ranges in extremely low frequency (ELF) band. The ELF band is the most significant bandwidth for underwater long-range communication. ELF band which is extended from 3 to 3000 Hz clearly, faces bandwidth limitation. Me...

Abstract— Wideband communications are impossible with signals that are spread over a very large band and are transmitted over multipath channels unknown ahead of time. This work exploits the I-mmse connection to bound the achievable datarate of spreading signals in wideband settings, and to conclude that the achievable data-rate diminishes as the bandwidth increases due to channel uncertainty. ...

Network covert channels enable a policy-breaking network communication (e.g., within botnets). Within the last years, new covert channel techniques occurred which are based on the capability of protocol switching. There are currently no means available to counter these new techniques. In this paper we present the first approach to effectively limit the bandwidth of such covert channels by intro...