Abstract: A method for transmitting information by radio over a wide bandwidth comprises the steps of: inputting a data signal into a time varying filter modulator; spreading the data signal in time and in frequency to produce a wideband signal; modulating the wideband signal onto an RF carrier to provide an RF output signal; and transmitting the RF output signal. The step of spreading includes performing a series of linear transformations to the data signal.

Abstract: A tunable laser produces laser emission at at least two wavelengths simuleously. The tunable laser includes at least two gain elements, where each gain element generates a different wavelength. Means for optically exciting each laser gain element is appropriately disposed for either end pumping or side pumping to produce a laser emission within a preselected range of wavelengths. A wavelength dispersing element such as a prism is disposed in the laser resonator cavity for dispersing the wavelengths operating simultaneously within the laser resonator cavity and to create separate regions for each laser gain element. Laser gain elements may be tunable laser gain elements or discrete emitting laser gain elements. Arbitrarily large wavelength separations between the wavelengths operating simultaneously may be achieved in this manner producing stable cw or pulsed output, Q-switched or line narrowed depending on the means disposed within the laser resonator cavity.

Abstract: A band-pass sigma-delta modulator includes a translator for tuning to a selected signal passband within the tuning range of the modulator. In a network implementation, the translator is integral with each integrator associated with the sigma-delta modulator(s). The translator can comprise a network having a transfer function defined in the Z-domain as (Z.alpha.-1)/(Z-.alpha.), where -1.ltoreq..alpha..ltoreq.1 defines the tuning. The value of .alpha. is defined as .alpha..tbd.cos(2.pi.f.sub.gm /f.sub.s), where f.sub.gm is the geometric mean frequency of the passband and f.sub.s is the input sample frequency of the sigma-delta modulator(s). The invention can benefit many signal processing applications such as, for example, A/D, D/A and D/D converters; and digital communication systems including digital radio and digital TV. In digital communications (e.g., radio, TV, etc.

Abstract: A thermal neutron detector comprises an enclosure containing a helium-xenon gas mixture, an optical fiber, and an electrode arranged to detect ion particles. The optical fiber detects photons generated by a reaction of the gas mixture with neutrons passing through the enclosure. The reaction also generates ion particles that are detected by the electrode. A coincidence detector generates an output signal corresponding to the correlation of ion detections from the electrode with photon detections from the optical fiber, rejecting signals generated from the electric field that are not correlated with photon detections.

Abstract: A fastener retainer removal tool comprises a handle, a shank extending from he handle, and a tip at the distal end of the shank. The tip has a narrow portion and a wide portion divided by a slot that is tapered outward on one side. The other end of the slot is enlarged to hold a workpiece inside the slot. The narrow portion of the tip is used for guiding safety wire and cotter keys into the slot. The wide portion of the tip is used as a lever to assist in bending thick cotter keys.

Abstract: A superconducting transformer comprises a superconducting primary layer arranged to conduct an externally supplied primary electric current around a primary core to establish a magnetic flux through the primary core. The superconducting primary layer is formed on a primary substrate of electrically insulating, non-magnetic material. A superconducting secondary layer is arranged to conduct a secondary electric current around a secondary core. The superconducting secondary layer is formed on a secondary substrate of electrically insulating, non-magnetic material. The primary and secondary cores are made of a non-saturating material. The secondary electric current is generated by stacking the layers to couple the magnetic flux from the primary core to the secondary core. Superconducting vias are formed through the primary, isolation, and secondary layers for making external connections to the transformer.

Abstract: A method is described for fabricating a complementary, vertical bipolar sconducting structure. An N+ silicon island and a P+ silicon island separated by a first oxide layer are formed on a sapphire substrate. An NPN junction device is formed on the N+ silicon island by epitaxially growing an N-type silicon layer on the N+ silicon island. Then, a P region is created in the N-type silicon layer. An N+ region created in the P region completes the NPN junction device. Similarly, a PNP junction device is formed by epitaxially growing a P-type silicon layer on the P+ silicon island. Then, an N region is created in the P-type silicon layer. A P+ region created in the N region completes the PNP junction device.

Abstract: A buried, gate insulator field effect transistor is disclosed. It comprises source, drain, substrate, gate, and a gate insulator layer separating the gate from the source, drain and substrate; and a protective silicon dioxide covering layer. Windows are excised into this covering layer to allow electrical connection to the source, substrate, drain, and gate. The substrate and gate are vertically aligned in the resulting structure. The source, drain and gate are fabricated from a doped, semiconductor of one polarity while the substrate is fabricated from doped semiconductor of the opposite polarity. The gate insulator layer is fabricated by implanting an element or elements selected from Group V, VI or VII into the semiconductor to form a semiconductor-compound insulator. Methods of fabricating this device are also disclosed. In one embodiment the device is fabricated on an insulating base layer. The gate is formed next to the base. In a second embodiment, no base is used.

Abstract: Transmitted signals are used to accurately and remotely determine the veral distance of an earth-based receiving antenna above a surface, and hence can be used to determine the tide condition of a water surface. A signal is transmitted from a signal source as it moves either through air or space. An antenna whose height is to be determined with respect to a reflecting surface, such as water, receives the signal directly from the signal source and indirectly from the signal source by reflection of the signal from the reflecting surface. The sum of the directly and indirectly received signals form an interference pattern as the signal source is moved. Points on the interference pattern are selected at identical phase angle for each cycle of the pattern. The points are assigned reference numbers and the numbers are plotted with respect to a measurement indicative of the distance between the signal source and the antenna whose height with respect to the reflecting surface is to be determined.

Abstract: Signals are processed along two paths, one determining the optimum freque band from which atmospheric noise will be analyzed and the other which performs statistical analysis of the frequency band found to be optimum. The band-setting path may include broadband filtering to limit a search to a desired band. A fast Fourier transform (FFT) sorts the analog-to-digitally converted signals into consecutive frequency bands identified herein as frequency bins. The magnitude of the signals falling within each frequency bin is determined and the average frequency bin magnitude is ascertained. Broadband peaks are searched by noting which frequency bin magnitudes are a predetermined amount over the average frequency bin magnitude. These frequency bins are "marked" and the bins are then searched to determine the longest series of frequency bins between marks, thereby determining the widest frequency band bounded by broadband signals.

Abstract: The invention provides a method for detecting signals in non-Gaussian background clutter, comprising the steps of: 1) filtering input data to partition Gaussian input data from non-Gaussian input data; 2) estimating the intensity level of the Gaussian input data; 3) determining the probability distributions of the non-Gaussian input data; 4) determining the background noise level of the input data; 5) estimating noise parameters of the input data; 6) estimating the residual intensity of the input data using the noise parameters; 7) determining a detection statistic M from the input data, estimated noise parameters, and the residual intensity of the input data; 8) determining a standard deviation N.sub.i of the detection statistic, M.sub.i ; 9) determining a normalized detection statistic Si, where S.sub.i =M.sub.i /N.sub.i,; 10) determining a maximum value, S.sub.imax of S.sub.i ; 11) determining a mean value S.sub.Mean and standard deviation S.sub.Std dev of all S.sub.i excluding S.sub.

Abstract: A method for manufacturing an optical RF bandpass filter comprises the st of: (1) mounting an optical fiber having first and second ends in a fiber support structure having first and second surfaces so that the first end is exposed at the first surface and the second end is exposed at the second surface; (2) forming a first layered mirror structure on a first substrate to create a first mirror wafer structure having a first reflective surface; (3) forming a second layered mirror structure on a second substrate to create a second mirror wafer structure having a second reflective surface; (4) affixing the first reflective surface of the first mirror wafer structure to the first surface of the fiber support structure; and (5) affixing the second reflective surface of the second mirror wafer structure to the second surface of the fiber support structure.

Abstract: An automatic medical monitor of the present invention comprises medical s sensors for collecting a time-ordered set of values representative of medical signs such as pulse, respiration, and blood pressure. The medical sign sensors are coupled to a medical sign data processor that forms statistics from the medical sign data and forms a modified Fast Initial Response (FIR) Shewhart cumulative sum and a variance cumulative sum to detect changes in health state. When a change in health state is detected, the medical sign data processor displays the statistics on a display and logs them on a printer.

Abstract: In an umbrella top-loaded monopole (UTLM) antenna, the charge distribution on top-load radials increases approximately linearly from the top of the antenna because the activated wires are separating from the tower and each other at the same time they are getting closer to ground. The UTLM antenna of the invention incorporates a top-load configuration in which top-load elements, whether they be radiating or receiving, are arranged in the shape of frames that originate at the top of the antenna and that extend away from the antenna towards the antenna's base where, at those points of the configuration furthest from the antenna tower and closest to ground at least two top-load elements converge to shield each other and hence reduce charge density. The top-load frames may be arranged contiguously such as in a rosette configuration. The self-shielding effect of the invention permits an antenna to operate at considerably higher voltage.

Abstract: An elongate towed acoustic array is improved by the inclusion of a speciflly configured tensile load bearing strength member disposed within a hose-shaped sheath. The member has a plurality of longitudinally extending high strength cords formed of braids or strands of high tensile strength fibers. The cords are held in a longitudinal juxtaposed relationship by a transverse weave to define a hollow interior for non-compressively containing sensor elements. Thusly configured, the strength member possess a softness and flexibility that does not create damage inducing crimps while not overly interfering with the sensors' acoustic sensing capabilities. The hose-shaped sheath contains the tubular-shaped strength member in a non-compressive relationship to reduce the problems normally associated with flow noise. The cords are braided together in an eye-splice where they are wrapped about towing pins so that the cords' tensile strength is not compromised at the point of attachment.

Abstract: A dielectric power transformer comprises a tuning inductor having a nonmatic core connected in parallel with a capacitive voltage divider. The dielectric power transformer transforms the voltage of an alternating current power source connected across the inductor into a voltage across a load connected to the capacitive voltage divider. The dielectric power transformer has a resonant frequency substantially equal to the frequency of the power source.

Abstract: A buoyed sensor array communications system comprises multiple sensor syss electrically connected to a signal transmission line which are positioned at predetermined locations along the signal transmission line to form a linear sensor array. Each of the sensor systems generates a data signal in response to receiving an address signal. The system further includes; a processor system electrically connected to the signal transmission line for transmitting address signals to enable any one of the sensor systems at a time in a selectively accessed order and has a data storage memory for storing the data signal from each of the sensor systems as stored data. A radio frequency transmitting system is coupled to the data processor and transmits the stored data at a predetermined time. A negatively buoyant structure connected to the signal transmission line pulls the communications system to the bottom of a body of water upon deployment.

Abstract: An acoustic communication system comprises: a voice processing circuit wh generates a first signal representing a voice message; a noise sensor channel which generates a second signal in response to detecting background noise in an environment; a microcomputer which receives the first and second signals, and provides a third signal to a selected one of first and second output ports of the microcomputer, where the amplitude of the third signal is functionally related to the value of the second signal; an ultrasonic output channel coupled to the first output port and which generates an ultrasonic output signal representing the voice message in response to receiving the third signal; a pubic address channel coupled to the second output port which generates an audible signal representing the voice message in response to receiving the third signal; and an ultrasonic receiving system which generates an audible output representing the voice message in response to receiving the ultrasonic output signal.

Abstract: Electroluminescent devices are formed on a transparent sapphire substrate follows. Crystalline silicon is formed on the sapphire substrate and patterned into a mesa. An electrode of, for example, titanium silicide, is formed in the silicon around the mesa, and an electrically insulating layer is formed over the electrode. The crystalline silicon is exposed on the mesa, and a porous silicon layer is formed on the crystalline silicon. An electrode made of aluminum, for example, is formed on the porous silicon layer. This electrode need not be transparent. An outer insulating layer may be formed on the aluminum electrode and additional electrodes may be formed on and through the outer insulating layer to make electrical contact with the titanium silicide and aluminum electrodes, respectively. A voltage source may be connected to the electrodes to pass a current through the porous silicon to cause light to be emitted from the porous silicon through the sapphire substrate.

Abstract: A system for controlling multiple computer directed devices, comprises: a supervisor computer which receives input data serving as operand inputs to a set of logical operators implemented in the supervisor, where the logical operators provide output results; assignable resources, including an m number of planner computers, where m is a positive integer, and an operator station computer; a link server computer; a local area network operably coupled to provide data communications among the supervisor computer, planner computers, operator station computer, and link server computer; and a p number of the devices communicatively linked to the link server computer; wherein the supervisor computer assigns a subset of the assignable resources to direct the operation of at least one of the devices in accordance with the output results.