Signal processing algorithms and architectures can use dynamic reconfiguration to exploit variations in signal statistics with the objectives of improved performance and reduced power consumption. Parameters provide a simple and formal way to characterize incremental changes to a computation and its computing mechanism. This paper examines five parameterized computations which are typically implemented in hardware for a wireless multimedia terminal: 1) motion estimation, 2) discrete cosine transform, 3) Lempel-Ziv lossless compression, 4) 3D graphics light rendering and 5) Viterbi decoding. Each computation is examined for the capability of dynamically adapting the algorithm and architecture parameters to variations in their respective input signals. Dynamically reconfigurable low-power implementations of each computation are currently underway.

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Water leakage is a significant problem in both developing and developed countries causing water loss in waterdistribution systems. Leakage causes economic loss in the form of wastage of water, damage to pipe networks and foundations of roads and buildings, and also poses risk to public health due to water contamination. The lost or unaccounted amount of water is typically 20-30 percent of production. Some older systems may lose even up to 50 percent. The water pipe networks in houses as well as public places are generally concealed and hence detecting water leakage in the initial stages before an upcoming damage is difficult. The existing technologies for detecting leakage have various limitations such as efficiency being dependent on size, material and depth of pipes, need for manual intervention, dependency on weather and surface conditions and effect of water pressure. In this paper, we propose an automated water leakage detection system using a wireless sensor network created along the distribution pipes based on thermal (IR) imaging. Thermal imaging has the capability to work in low lighting or dark conditions and helps in capturing the contrast between hot and cold areas created due to water leakage. A network of low cost, low power thermal imaging sensors each having its own processing and Radiofrequency (RF) Transreceiver units and operating independent of pipe, weather or surface conditions is proposed in this paper. A central database is updated on a realtime basis, enabling very early leakage detection and initiating subsequent action to address the problem. An example system evaluation is performed and results highlighting the power and cost impact of the sensor network system are presented.

Global Positioning System (GPS) signals are spread spectrum, modulated with very low average power caused by background noise. Signal received is mostly 165 dB down than thermal noise level. Such signals are easily jammed either through intentional noise sources (jammer) or unintentionally from broadcasting stations harmonics or other out of band sources. This study proposes to reveal how a nulling antenna with adaptive spatial filtering technique can efficiently mitigate intentional and non-intentional interference. A beam forming antenna array is an antennas set whose outputs are weighted by complex values and combined form array output. The complex valued weights effect is to steer the array pattern's main lobes to desired directions which may be unknown and hence antenna weights are adjusted adaptively till some array performance measure is improved, revealing proper lobe or null placement. This study proposes a Cuckoo Search (CS) algorithm based new optimization method for multiple interference cancellation design that increases gain to desired signal and improves jamming rejection performance.

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