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.
Linear coding schemes for noiseless feedback channels have been well studied. These schemes have been shown to display favorable properties for a broad class of Gaussian noise processes. However, the design of linear codes for noisy feedback channels is much less developed. In this work, an analytical expression for the optimal linear code for the additive white Gaussian noise feedback channel is...
In recent years, hybrid-automatic repeat request (ARQ) protocol has become one of the most popular packet transmission schemes. Hybrid-ARQ aims to combine the advantages of forward error correction codes with the traditional ARQ scheme to increase the reliability and throughput of the network. In this paper, we look at improving upon this performance for block fading channels (e.g., Rayleigh, Rician,...
Air and fuel mixtures for diesel combustion can be enhanced by using a pulsed millisecond electrical discharge. The current and voltage of such a discharge needs to be measured in this type of experiment using a standard pulsed measurement technology based on a high voltage probe and current transformer. The experimental data and data evaluation of breakdown threshold voltages for mixed air and diesel...
Using an information theoretical perspective, we explore quantitative methods for exploiting the spatial diversity offered by multiple widely separated antennas for radar imaging applications. While decomposing the operation of multistatic radar into multiple bistatic components, we proceed to characterize relevant conditional mutual information quantities between the underlying channel and bistatic...
Allowing the receiver in a multiple antenna wireless system to send a limited amount of channel state information (CSI) feedback is an effective way to enable channel adaptive signaling. This paper addresses the problem of controlling the feedback update period and feedback rate of limited feedback multiple antennas systems in temporally correlated channels. The challenge in our problem is how to...
We present an innovation value chain analysis for a representative sample of new technology based firms (NTBFs) in the UK. This involves determining which factors lead to the usage of different knowledge sources and the relationships that exist between those sources of knowledge; the effect that each knowledge source has on innovative activity; and how innovation outputs affect the performance of...
Advanced cooperation strategies in multi-user multi-input multi-output (MU-MIMO) wireless communication systems could be facilitated by knowledge of global channel state information (CSI). Obtaining global knowledge of CSI in such MU-MIMO systems, where each user knows the CSI between every pair of users, would enhance cooperation amongst users and also improve the performance of such systems. In...
The design of beamformers using limited channel state feedback at the transmitter for multiple-input single-output (MISO) fading channels has been extensively studied in the literature. It has been established that the limited feedback of channel state can lead to significant capacity enhancement. In this paper, it is demonstrated that the use of channel output feedback in addition to limited channel...
The availability of a noiseless feedback channel can allow for simplistic transmission schemes with very high reliability; such advantages were solidified by a linear feedback scheme developed by Schalkwijk and Kailath (S-K). However, the S-K scheme and related techniques rely on the presence of a noiseless feedback channel which is not practical. In this paper, we look at introducing the notion of...
Communications systems operating over additive Gaussian noise channels with no feedback or ideal channel output feedback are now well studied. However, these set-ups model extreme cases and fail to provide much insight into more practical feedback systems. Therefore, in this paper, a noisy feedback communication system is considered. We study the application of linear multi-dimensional coding of the...
This paper concerns a simple limited feedback scheme taking temporal correlation into account during the feedback design in slow fading environment. In this method, the transmitter and the receiver reuse the past channel state information (CSI) as side information. Feedback, that is designed to leverage the side information, is sent from the receiver to the transmitter using a predetermined update...
In certain communications systems, it is a reasonable to assume the presence of a noisy feedback channel. The ability to send data from receiver back to transmitter opens new doors in the way of modulation schemes. In this paper, we investigate the class of linear feedback encoding schemes in which the transmitter linearly encodes the feedback information along with the message to be sent. Given a...
The integration of the feedback channel into a coding scheme cannot increase capacity but still has many benefits such as higher reliability and lower complexity. In the class of linear feedback coding schemes, one of the most well-known is the Schalkwijk-Kailath coding scheme. Using the same framework, an optimized coding scheme is produced using linear algebraic tools, and this scheme is compared...
We study the problem of quantizing an M dimensional beamforming vector with M relatively large. Using a conventional beamforming vector codebook to quantize beamforming vectors incurs a complexity that scales exponentially with M, making it unsuitable when M is large. In, we proposed to use a trellis-based quantization scheme to tackle the complexity problem, and we present two enhancements in this...
It is shown that pure bend loss from an LED-excited multimode slab waveguide in the classical geometric optics limit of zero wavelength has a simple analytical solution that readily exhibits all the parametric dependence of the problem.
The Collaborative Sensing Language (CSL) is a high-level feedback control language for mobile sensor networks (MSN). It specifies MSN controllers to accomplish network objectives with a dynamically changing ad-hoc resource pool. Furthermore, CSL is designed to allow the updating of controllers during execution (patching). This enables hierarchical control with simpler controllers at lower levels....
For multicasting applications over multiple-input multiple-output (MIMO) channels with certain kind of QoS requirement, it is more suitable to design a strategy that minimizes the number of the dropped users during one multicasting session. The immediate benefit of this strategy would be to effectively improve the outage capacity of each receiver. The major contribution of our paper is a precoded...
A new type of optical probe, based on a fractal fibre which is a special class of photonic crystal fibre (PCF), is introduced to directly address the issue of increasing the optical throughput in SNOM probes.
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.