Altarum Institute

University of Michigan

Michigan Technological University

Joseph W Burns

Christopher Roussi

Nikolas Subotic

Nikola Stevan Subotic

Ronald D Chervin

Vincent Canella

Methods and systems for diagnosing or assessing rapid eye movement sleep behavior disorder (RBD). Muscle tone or activity variance during rapid eye movement (REM) and non-rapid eye movement (NREM) sleep intervals of a polysomnogram are compared. A threshold based on the NREM data is used to identify a subject-specific threshold for abnormality in the REM variance. A metric that includes the percentage of REM variance exceeding the threshold relates to RBD.

Automated polysomnographic assessment for rapid eye movement sleep behavior disorder

A system and method for determining respiratory cycle-related EEG changes (RCREC) for a subject with sleep-disordered breathing are provided. The method includes receiving an EEG signal from the subject using at least one sensor, and defining at least two respiratory cycle segments within each respiratory cycle. The method further includes determining an EEG power of the EEG signal during each of the at least two respiratory cycle segments, and determining RCREC by calculating a difference between a maximum EEG segment power and a minimum EEG segment power.

System and method for analysis of respiratory cycle-related EEG changes in sleep-disordered breathing

A substrate is provided with a multiplicity of electrically conductive elements, and the elements are interconnected to form an antenna structure for desired application. Either the antenna pattern itself may be altered according to the invention, or one or more feed points may be changed, or all of the above. As such, the electrically conductive elements may be interconnected to change the directionality of the antenna pattern, the gain, the frequency response, or other operational characteristics. The electrically conductive elements may be arranged in the form of an inchoate antenna pattern or regular array. Switches at key points of the structure enable the pattern to be changed dynamically. Such switching may be carried out in real time in accordance with transmissions/reception characteristics, or in advance using simulations associated with the switched elements.

Methods and apparatus for reconfiguring antenna array patterns

An approach to antenna design optimizes gain, beam pattern, polarization response, and other qualities through self-replicating patterns based upon iterative transformations and candidate geometric shapes. In the preferred embodiment Hausdorff structures are used to realize &lgr; -arbitrary different radiation patterns, including patterns optimized for multiple frequencies. The most preferred approach applies a sequence of different Hutchinson operators to different geometric subsets, thereby achieving patterns which are not only arbitrary in terms of wavelength/frequency, but also permit variable radiation patterns and variable polarization other desirable criteria. In addition to the use of variable scaling, geometric patterns, and the like, multiple structures may be placed within the same spatial footprint to permit reception over more bands. A dynamic reconfigurable antenna array is provided according to an alternative embodiment, enabling a single device to be simultaneously tuned to different or multiple frequencies or other response criteria. The antenna array may be made directional in its radiation (or reception) pattern either by changing the configuration of the array, changing the feed points in the array, or electrically steering the pattern using standard beam formatting techniques on multiple taps. Once a particular antenna architecture is defined, electrical or micro-mechanical switches are placed at key points of the structure enabling the pattern to be changed dynamically. Alternatively, a reconfigurable multi-dimensional array may be used having an active area optimized to maximize reception for a desired frequency and/or directionality.

Antenna structures based upon a generalized hausdorff design approach

The relative movement of a receiver and transmitter in a communications system is used to advantage by electronically synthesizing a larger apparent antenna aperture, thereby increasing signal-to-noise ratio. The approach may be used regardless of whether the transmitter is fixed and the user or vehicle is moving, or the user or vehicle is fixed and the transmitter is moving. According to the method, the apparent angle between the receiver and transmitter is determined relative to the direction of movement and used to produce time-delayed replicas of the received signaling stream which are coherently added to synthesize the increased apparent receiver antenna aperture. Since only the receiver is modified according to the invention, existing transmitters and infrastructures can be used without modification. Although some data buffering is required, only a few number of beams need to be synthesized, in contrast to more complex military SAR configurations.

Synthetic-aperture communications receivers

An antenna pattern disposed on a three-dimensional object is used to optimize gain, beam pattern, polarization response, or other qualities despite or independently of physical orientation. In the preferred embodiment a fractal array is used on a polyhedron, though non-fractal and other self-replicating antenna patterns may be generated through the use of additional transformations and candidate geometric shapes to achieve patterns which are not only arbitrary in terms of wavelength/frequency, but also permit variable radiation patterns and variable polarization other desirable criteria. In addition to the use of variable scaling, geometric patterns, and the like, multiple structures may be placed within the same spatial footprint to permit reception over more bands. As an alternative to a fixed pattern with switches used to swap elements or change feed points, a reconfigurable multi-dimensional array may be used having an active area optimized to maximize reception for a desired frequency and/or direction. This aspect of the invention may exploit flat-panel technology, wherein, for example, a conductor array face on the object may be mapped to an addressable interconnect back plane to achieve a desired level of reconfigurability.

Growing community of inventors

Ann Arbor, MI, United States of America

Joseph W Burns