Other

Morgan State University

Richard A Dean

Tharold Eugene Northup

Tasmeer Alam

Matin Dinca

Wondimu K Zegeye

Clem Abrams

Farzad Moazzami

Systems and methods are provided for reducing peak-to-average power ratio ('PAPR') in an orthogonal frequency division multiplexing ('OFDM') signal having reference tones by introducing modified pilot tones to cancel peaks in OFDM symbols in the OFDM signal array. The modified pilot tones are added to the original OFDM signal, which in turn conditions the OFDM symbols of the signal to effectively reduce the PAPR. Such systems and methods provide PAPR reduction for OFDM signals generated by an OFDM Signal Processor through the addition of tone reservation PAPR reduction methods, which use reserved tones such as pilot tones to improve PAPR. Such methods offer an advantage of improving the PAPR without introducing distortion to the signal.

Systems and methods for peak-to-average power ratio (PAPR) reduction in OFDM signals

Systems and methods are provided for transmitting OFDM signals through a communication channel exhibiting frequency selective fading, such as an aeronautical 2-ray channel, using a signal modulation scheme at the transmitter that is selected based on a measurement of signal to distortion ratio (SDR) at the receiver. The SDR measurement at the receiver is used to generate an estimated best modulation scheme based on the real-time detection and measurement of SDR at the receiver, and provide feedback to the transmitter through a feedback channel of the newly selected modulation scheme. In certain configurations, the selected modulation scheme is one of multiple possible quadrature amplitude modulation (QAM) schemes, which enables adaptation of the transmitted OFDM signal to optimize throughput based on distortion of individual tones of the OFDM signal received at the receiver.

Systems and methods for OFDM performance enhancement on frequency selective fading channels

Disclosed herein are methods and systems that apply a multi-layer Hidden Markov Model (HMM) for intrusion detection. The methods and systems employ a dimension reduction technique to extract only important features from network packet data and apply a decomposition algorithm to lower levels of data to construct lower level HMMs (representing partial solutions), which lower level HMMs are then combined to form a final, global solution. The multi-layer approach can be expanded beyond the exemplary case of 2 layers in order to capture multi-phase attacks over longer spans of time. A pyramid of HMMs can resolve disparate digital events and signatures across protocols and platforms to actionable information where lower layers identify discrete events (such as network scan) and higher layers identify new states which are the result of multi-phase events of the lower layers.

Method and system for intrusion detection

A keyboard with a thumb-controlled curser. In a preferred embodiment a circular aperture about one centimeter in diameter is provided in the spacebar of the keyboard. A keyboard user controls the position of the computer curser by moving a portion of his thumb across the port. A light source illuminates an exposed surface of the user's thumb as it moves across the port. Light patterns reflected from the user's thumb are focused on a sensor. The output from the sensor is transmitted to the computer processor where the thumb movements monitored by the sensor are turned into control signals for controlling the position of the curser on a computer monitor.

Keyboard with thumb operated spacebar curser controller

A container body has a main opening large enough to permit passage of large paintbrushes or sprayer suction lines and filters. This opening is covered with a large cap that comprises a bayonet-type seal. Special features in the cap and in the body combine to provide a swivel pour valve permitting contents of the container to be poured from the can in a controlled manner with no spillage or mess. The cap has a close position, a remove-replace position and a pour position. A sealed-closed position is achieved with cap rotation in a first rotation direction from a first cap remove-replace position and the pour position is achieved by cap rotation in the same rotation direction from a second cap remove-replace position. Preferably a pour vent is provided. It could be covered with a threaded screw or snap-on cover.

Clean container for paint and other fluids

A can for holding paint and similar products. The can has a rectangular bottom, preferably square, and rectangular sides providing a space savings of about 20 percent as compared to round cans. It has a main opening large enough to permit passage of large paint brushes or sprayer suction lines and filters. This opening is covered with a large cap. A swivel pour valve permits paint to be poured from the can in a controlled manner with no spillage or mess. In a preferred embodiment, the swivel pour valve is an integral part of the large cap covering the large opening. The can is preferably made of plastic which eliminates problems of rust and other corrosion problems.

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Baltimore, MD, United States of America

Richard A Dean