Abstract: Intrusion detection methods and apparatus exploit the infrastructure of the building itself. The preferred embodiments use the existing power line infrastructure to provide power, data, and sensor observables to a monitoring system which is simply connected at one point, namely, the connection of the building to the city power grid. Computer network interfaces may also be used. In terms of sensors, impedance, capacitive, inductive, electric field and Radar modalities may be used.

Abstract: Intrusion detection methods and apparatus exploit the infrastructure of the building itself. The preferred embodiments use the existing power line infrastructure to provide power, data, and sensor observables to a monitoring system which is simply connected at one point, namely, the connection of the building to the city power grid. Computer network interfaces may also be used. In terms of sensors, impedance, capacitive, inductive, electric field and Radar modalities may be used.

Abstract: 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.

Abstract: 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;n-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.

Abstract: Broadly, this invention resides in apparatus and methods involving a set of soundfield nulling algorithms providing a localized decrease in sound intensity. Among the benefits of the approach, is that there is little, if any, affect on other important positions such as power or spectral content, insofar as energy is directed to unimportant areas. In the preferred embodiment, two separate algorithms are used, depending upon the frequency range of the acoustic signal. For lower frequencies (for example, less than 300 Hz), the algorithm is based on Cepstral techniques and overtly uses the fact that in an enclosed area, the predominant acoustic influence is in the form of standing waves. At higher frequencies, however, (i.e., 300 Hz and above), the sound is due to free-space propagation. Consequently, single free-space algorithms that are applied across the spectrum have great difficulty in providing useful sound nulls without distortion.

Abstract: 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;n-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.