Abstract: A variety of methods and devices for a low-probability of intercept, low probability of denial (LPI/LPD) method of providing RF signals in denied spaces are disclosed. A phased array antenna converts an omnidirectional communication system into a highly directional system. This factor coupled with the precise timing between the transmit and receive sets, establishes a precise distance measurement between the two sets. Using three or more transceivers enables the composition of an ad hoc network of nodes that can be used to establish an available mesh of position and timing that can be accessed by operators within the radio boundaries of the mesh. Portable transceivers reestablish position, navigation and timing (PNT), thereby forming an ad-hoc network. Where the ad-hoc network PNT mesh can intersect with a GPS signal that is outside of the denied environment, the ad-hoc network mesh can detect the GPS position and timing.

Abstract: Compact bidirectional repeaters are provided for wireless communication systems. Their compact size is realized with repeater structures that include different-polarization antennas, back lobe suppressing structures, circuit feedback paths, antenna-feedback detectors, and automatic gain control.

Abstract: Compact bidirectional repeaters are provided for wireless communication systems. Their compact size is realized with repeater structures that include different-polarization antennas, back lobe suppressing structures, circuit feedback paths, antenna-feedback detectors, and automatic gain control.

Abstract: Local-oscillator systems for wireless communication systems are realized with oscillator networks that are phase locked to a bit timing clock. Two of the networks provide first and second phase coherent local-oscillator signals respectively to a receiver and transmitter of a transceiver. A third oscillator system forms a phase lock loop about one of the other networks and preferably includes a crystal to enhance short term stability. Because they track the bit timing clock, the first and second local-oscillator signals phase track all communication signals in the transceiver's communication system.

Abstract: Wireless communication methods and structures are provided that enhance communication robustness while reducing cost. They communicate downstream data with orthogonal frequency division multiplexing (OFDM) transmission processes and upstream data with single carrier transmission processes. This combination of transmission processes is configured with various signal modulations (e.g., quadrature phase shift keying (QPSK), m-ary phase shift keying (MPSK) and n-quadrature amplitude modulation (QAM)) to provide lower cost upstream communication from customer services equipments (CPEs) and more robust downstream communication from headends than has been achieved in conventional communication systems. Signal diversity is enhanced by receiving communication signals with multiple antennas that are spatially separated and have different polarizations to thereby enhance frequency diversity.

Abstract: Communication systems and methods are provided for communicating data signals over a plurality of different respective communication channels. The systems are realized with sets of signal filters wherein each filter set defines a respective communication channel. The filters of each set are distributed among transceivers which are coupled together with a two-conductor medium. The systems and methods provide communication to a significant number of communication end-users over a substantial number of communication channels without the need for complex modulation and demodulation hardware.

Abstract: Wireless communication methods and structures are provided that enhance communication robustness while reducing cost. They communicate downstream data with orthogonal frequency division multiplexing (OFDM) transmission processes and upstream data with single carrier transmission processes. This combination of transmission processes is configured with various signal modulations (e.g., quadrature phase shift keying (QPSK), m-ary phase shift keying (MPSK) and n-quadrature amplitude modulation (QAM)) to provide lower cost upstream communication from customer services equipments (CPEs) and more robust downstream communication from headends than has been achieved in conventional communication systems. Signal diversity is enhanced by receiving communication signals with multiple antennas that are spatially separated and have different polarizations to thereby enhance frequency diversity.

Abstract: A combination enclosure and electrical apparatus includes an electronic control circuit which provides multiple modes of operation of electrically operated devices connected thereto. The electrical apparatus is connected to a power supply, such as a common residential alternating current power source, and includes receptacles for connecting the electrical apparatus to electrical devices to be controlled thereby. The control circuit is electrically disposed intermediate the power supply and the receptacles and controls the operation of connecting the power supply with the receptacles for powering the connected electrical devices. A rotary switch permits a user to select from multiple preselected modes of operation, which are stored or effected by the control circuit, to effect the desired operation of the connected electrical devices.

Abstract: The invention provides methods and apparatus for atomic emission spectroscopy and for mass spectrometry which make use of an inductively coupled radio-frequency plasma torch. A radio-frequency power supply supplies energy to a plasma induction coil via reflectometer means and a matching network. A signal indicative of reflected power generated by the reflectometer is used to set the frequency of the power supply to the resonant frequency of the matching network and plasma induction coil, thereby ensuring the maximum efficiency of power transfer irrespective of the state of the plasma. Preferably a solid state power amplifier is employed in conjunction with a lower power variable frequency oscillator. Means for ensuring proper ignition of the plasma while maintaining the frequency of the power generator within a governmentally specified frequency band are also provided.

Abstract: The Echographic Suction Cannula and Electronics Therefor provides a display of adipose tissue thickness for the Doctor to observe as he moves the cannula within the patient. The cannula includes a piezoelectric transducer which is pulsed by the electronics as a send pulse, to cause ultrasound to penetrate the adipose tissue and provide a reflected receive pulse. A known value fixed frequency source continuously emits cycles, and the electronics counts the cycles emitted between the send and receive pulses. This number is fed to a computer which generates bars equal in height to the thickness and moving across the CRT as the Doctor moves the cannula so he can determine regions where further Liposuction is necessary to even out the patient's appearance.