An obvious approach to image enhancement is to sharpen bright regions of an image more than darker regions. One very simple method to accomplish this is to weight the amount of highpass filtering proportional to the local mean. This gives rise to a class of nonlinear image enhancement filters known as mean-weighted highpass filters. We propose a ...

This paper presents a general framework for designing optimal transmit spectra for communication services dominated by crosstalk --- for example Digital Subscriber Lines (DSLs) and wireless LANs. Using the channel, noise, and interference transfer functions, we set up and solve an optimization problem to maximize the joint channel capacity. We employ ...

We describe a new imaging method that uses single-cycle pulses of terahertz (THz) radiation. This technique emulates data-collection and image-processing procedures developed for geophysical prospecting and is made possible by the availability of fiber-coupled THz receiver antennas. We use a simple migration procedure to solve the inverse problem; ...

High capacity data transfers over the Internet routinely fail to meet end-to-end performance expectations. The default transport control protocol for best effort data traffic is currently TCP, which does not scale well to 100 Mbps and higher networks over long distances. In congestion avoidance, TCP is not swift enough to fully utilize resources over ...

The discrete wavelet transform (DWT) gives a compact multiscale representation of signals and provides a hierarchical structure for signal processing. It has been assumed the DWT can fairly well decorrelate real-world signals. However a residual dependency structure still remains between wavelet coefficients. It has been observed magnitudes of wavelet ...

In wireless sensor networks, energy and communication bandwidth are precious resources. Traditionally, layering has been used as a design principle for network stacks; hence routing protocols assume no knowledge of the application behavior in the sensor node. In resource-constrained sensor-nodes, there is simultaneously a need and an opportunity to ...

We study the problem of locating in space and over time a network pathâ s tight link, that is the link with the least available bandwidth on the path. Tight link localization benefits network-aware applications, provides insight into the causes of network congestion and ways to circumvent it, and aids network operations. We present STAB, a light-weight ...

We present several methods for implementing optimal HDSL2 transmit spectra that, at activation, adapt to the surrounding interference and noise. The methods are based around either a set of fixed transmit filters or a single adaptive transmit filter that uses the optimal transmit spectrum. Designing optimal spectra with minimum required power can ...

Dense networks of wireless, battery-powered sensors are now feasible thanks to recent hardware advances, but key issues such as power consumption plague widespread deployment. Fortunately, in a dense network of sensors, cross-sensor correlation can be exploited to reduce the communication power consumption. In this thesis, we examine a novel technique ...

The recently introduced theory of Compressed Sensing (CS) enables the reconstruction or approximation of sparse or compressible signals from a small set of incoherent projections; often the number of projections can be much smaller than the number of Nyquist rate samples. In this paper, we show that the CS framework is information scalable to a wide ...