Abstract: A method and system for increasing the effective communications channel bandwidth beyond that of the constrained physical bandwidth of a given channel by orthogonal signal spectrum overlay (OSSO) comprising: decomposing the time-bandwidth product (TBP) of a given symbol in a data stream transmitted through a given bandwidth, expanding the TBP in terms of overlaid orthogonal signals such as Weber-Hermite (WH) functions that constitute the eigensignals of the symbol. The complete data stream is multiplexed to produce a plurality of data channels, each of which is encoded on an orthogonal signal by quadrature amplitude modulation. The overlay of these signals constitutes the OSSO symbol. The OSSO symbols are transmitted in quadrature format (I and Q) and are the result of the addition of orthogonal signals, each of which constitutes a separate overlaid communication channel, occupying the same physical bandwidth.

Abstract: A Radon transform of the image(s) or array(s); and convolution of the Fourier transform of any 1D filter or mask, e.g., wavelet filters, with a 1D Ram-Lak, or other band-limited filter; convolution of the resultant 1D filters with each of the 1D columns of the 2D Radon transform or projection space version of the image; and an inverse Radon transform of the now omnidirectionally filtered projection space version of the image either directly, or after transmission.

Abstract: High data rate inter-satellite communications links method for a plurality of satellites comprising providing, for each satellite, an ultrafast time hopping wireless satellite communications link of an allowed bandwidth in which data is transmitted using individual packets or pulses in a sequence of such packets or pulses, causing the individual packets or pulses to be short in duration so that the individual packets are pulsed and signal energy is spread over the allowed bandwidth substantially simultaneously and instantaneously. A time hopping sequential code is used to position the packets or pulses precisely in sequence thereby providing optimum use of frequency space and also providing noninterfering transmission channels due to the orthogonality of the coding scheme used.

Abstract: Ultrashort pulse time hopping code-division-multiple-access (CDMA) and time-division-multiple-access (TDMA) RF IR and optical communications systems in the time-frequency domain comprises a transmitter including a short duration pulse/packet generator for generating a short duration pulse/packet in the femtosecond to microsecond range and a controller for controlling the generator, code means connected to the controller for varying the time position of each short pulse/packet in frames of pulses/packets in orthogonal superframes of ultrafast time hopping code and time division multiple access format, precise oscillator-clock for controlling such timing, encoding modems for transforming intelligence into pulse/packet position modulation form, antenna/amplifier system. Preferably, the codes are orthogonal codes with the temporal coding of the sequence of ultrafast pulses/packets constituting the carrier for transmission by the antenna system.

Abstract: A system of enhancing target detection in a polarization modulated signaling system for detecting targets through one or more given media. A polarization modulated signal is generated and transmitted in the given medium which is the complex conjugate of the polarization modulated response over time of the combined medium and target. The wave equation for transmission through the medium, reflectance from the target and transmission through the one or more given media, is solved and the polarization modulation of the polarization modulated signal is adjusted to match the polarization response over time for maximum propagation through the one or more given media and maximum reflectance from the target over time.

Abstract: An ultrashort pulse time hopping code-division-multiple-access (CDMA) RF communications system in the time-frequency domain comprises a transmitter including a short duration pulse generator for generating a short duration pulse in the picosecond to nanosecond range and a controller for controlling the generator, code means connected to the controller for varying the time position of each short pulse in frames of pulses in orthogonal superframes of ultrafast time hopping code division multiple access format, precise oscillator-clock for controlling such timing, encoding modems for transforming intelligence into pulse position modulation form, antenna/amplifier system. A homodyne receiver is provided for receiving and decoding the coded broadcast signal, and one or more utilization devices are connected to the homodyne receiver. Preferably, the codes are orthogonal codes with the temporal coding of the sequence of ultrafast, ultrawideband pulses constituting the carrier for transmission by the antenna system.

Abstract: A system for obtaining optimum performance and optimum graceful degradation from Lie algebra descriptions of a spectrum of reconfigurable network architectures, including, neural nets and cellular automata comprised of interconnected nodes. The dynamic performance of the computational process is monitored by continued extraction of Liapounov exponent indicators, reconfiguring said reconfigurable network architecture when said indicators predict non-optimum performance. The reconfigurable networks are reconfigured and compensatory adjustments are made of signal sampling performance and operating system performance of said reconfigurable network architecture, and the operating system architecture is optimized to the computational task by reconfiguration of nodal capabilities and degree of interconnectedness between nodes to obtain any Lie algebra description architectural form between ideal neural net with maximum interconnectedness and ideal cellular automata with maximum nodal capability.

Abstract: A wide bandwidth radio wave communication system having a dual feed pair of cross-polarized antennas having a common axis and being at orthogonal angles to each other. A source of RF signals is coupled to the antennas and a shifter device is between at least one of the pair of cross-polarized antennas and the source of RF signals for modulating the polarization of RF signals launched by the pair of cross-polarized antennas.

Abstract: The present invention provides passive networks which act as the host to nonlinear and parametric interactions, with energy inputs to said networks being caused to "bleed off" auxiliary, and time-delayed conditioning flows resulting in phase modulations to the main input and which achieve, e.g., RF phase conjugation with cancellation of the noise modulation after two-way passage of beams between transmitter and receiver and when used in duplex arrangements. Also, passive networks for noise reduction in communications transmission due to conditioning of electromagnetic fields in higher order group symmetry form. Because a transmitted wave from a network of the present invention is in higher-order group symmetry form, and fields of such higher-order symmetry have a low probability of occurrence naturally, then environmental noise, which is of lower group symmetry form (usually, U(1) symmetry) and has a high probably of natural occurrence, will be excluded from a receiver matched to higher-order symmetry waves.

Abstract: A signalling system in time-frequency space for detecting targets in the presence of clutter and for penetrating media, includes a transmitter antenna system, receiver and processor system. The transmitter antenna system generates and launches into a medium containing the targets an energy pulse (wave packet) having a predetermined duration and frequency characteristic, and which energy pulse matches at least one of the following: 1) the time-frequency reflection characteristics of the target(s) but not the clutter, or 2) the penetration time-frequency dielectric window of the medium, or 3) the time-frequency characteristics of the window of the receiver. Preferably, the time-frequency wave packet is the complex conjugate of the impulse response of the combined medium and target.

Abstract: In an external lasing dye sensor system, a stream of lasing dye free-flows cross an open area inside a chamber. An air sample comprising chemical vapor contaminants is pumped or drawn into the chamber. A laser beam is introduced into the chamber intersecting the lasing dye. A chemical reaction between the contaminants and the lasing dye result in a change in the emission spectra of the lasing dye. The change in emission spectra is detected and thus provides an improved apparatus for detecting low concentrations of chemical vapors in an air sample.

Abstract: In a lasing dye sensor system, a stream of lasing dye freeflows across an ea open to the atmosphere. A chemical reaction between contaminants in the atmosphere and the lasing dye result in the change of emission spectra of the lasing dye. The change in emission spectra is detected and provides an improved apparatus and method for detecting low concentrations of chemical vapors in the atmosphere.

Abstract: A laser for generating a coherent output beam with a frequency equal to the um or difference of the frequencies of two input pumping beams or the harmonics thereof. The laser includes a lasing medium of the type with an inverse Faraday effect resonance frequency f.sub.1, a laser cavity with the lasing medium positioned therein, two coherent light sources for generating pumping beams at frequency f.sub.1 and f.sub.2, where the f.sub.1 beam is circularly polarized, and an optical system for directing the pumping beams into the lasing medium.

Abstract: An optical device for obtaining a 3-dimensional signature or a plurality of 2-dimensional signatures for a given sample in order to detect predetermined chemical agents. The device comprises a light channel with a first sensing optical fiber with a coating thereon which changes its absorptive and refractive properties in the presence of a predetermined chemical agent, and a second light channel with a reference optical fiber isolated from the sample. A scanning monochromator is utilized to apply light beams to the sensing and reference fibers, and an optical detector is used to cross-correlate the outputs from the sensing and reference fibers. A variable optical delay line is disposed in one of the fiber channels in order to scan from 0.degree. to 360.degree. in phase shift for each light frequency. A 2-dimensional cross-correlation is obtained for this scan at this frequency. The scanning monochromator is set to run through a series of light frequencies in a given bandwidth.

Abstract: A method and apparatus for detecting the wavelength of singlet state resonance fluorescence of a sample, wherein the sample is illuminated sequentially with various incident wavelengths. For each wavelength, linearly polarized and circularly polarized components are allowed to pass sequentially by a first polarizer to the sample. The sample emits light as a result of spontaneous molecular energy transitions. Four components of the emitted light are allowed to sequentially pass to a detector by a second polarizer. The intensities of these components are then detected, and these values can be employed to obtain a new ratio for each wavelength. The wavelength at which this ratio equals one is selected as the wavelength of resonance fluorescence. In one example, a computer is provided to control the illumination of the sample and the two polarizers, and also may be utilized to compute the above ratios.