Hewlett-packard Company

Lucent Technologies Inc.

National Semiconductor Corporation

Dieter Scherer

Bassel Hage Daoud

Ivan Pawlenko

Richard Franklin Schwartz

Michael J Wheeler

William E Strasser

Thomas L Grisell

Christopher E Gayle

A tuning circuit for adjusting an oscillation frequency of an oscillator circuit. The tuning circuit comprises a film bulk acoustic wave resonator (FBAR) having a series resonance frequency and a parallel resonance frequency, and an inductor coupled in series or parallel with the film bulk acoustic wave resonator. The series connection of the inductor and FBAR decreases the series resonance frequency. The parallel connection of the inductor and the FBAR increases the parallel resonance frequency. The tuning circuit further comprises a varactor coupled in series or parallel with the inductor and the FBAR combination. The varactor tunes the oscillation frequency over the increased tuning range.

Apparatus and method for extending tuning range of electro-acoustic film resonators

The invention is directed to techniques and mechanisms for measuring transmission loss of a cable comprising the steps of disabling an antenna connected to a second end of the cable, feeding an input signal having an energy level into a first end of the cable for transmission of the input energy toward the second end of the cable, measuring a reflected energy, reflected back toward the first end of the cable from the second end of the cable, and comparing the reflected energy to a input energy to determine a cable loss. Directional couplers may be used to sample the input and reflected energy to be measured. The information derived from the comparison of input and reflected energy measurements can then be used to calibrate a transmitter thereby optimizing performance.

Method and apparatus for measuring the transmission loss of a cable

An LMDS system including a base station, subscriber units and subscriber modems. Transmission frequencies between the base station and the subscriber units are specified by the Federal Frequency Commission. Signal frequencies between the subscriber units and the subscriber modems are specified by industry standards. The subscriber units couple and frequency translate modulated signals between the base stations and the subscriber modems. The frequency translation requires an intermediate transmit oscillator and a local oscillator. The intermediate transmit oscillator, however, can also be used to frequency translate a local oscillator signal within each subscriber unit down to a lower frequency which allows a low cost phase locked loop chip to be used to phase lock the local oscillator in each subscriber unit to a reference source. A pilot tone can be coupled onto modulated signals transmitted from the base station to the subscriber units. The pilot tone can be summed into the local oscillator phase locked loop within each subscriber unit to reduce the effects of signal transmission on the phase noise of the modulated signals. Furthermore, dual pilot tones can be coupled onto the modulated signal transmitted from the base station to the subscriber units. The dual pilot tones can be used to generate a reference signal within each subscriber unit.

Low-cost phaselocked local oscillator for millimeter wave transceivers

Transmit and receive programmable band select/transfer modules provide low cost means for selecting and translating spectral segments within sectors of a LMDS basestation. The modules are programmable to select spectral segments and translate the frequency of the selected segments to designated spectral positions in the sector's output signal. Each module shifts the frequency of an applied uwave signal to dispose a predetermined spectral segment about an IF frequency. The predetermined spectral segment is then selected using a fixed frequency filter at the IF frequency. The spectral segment has one of several bandwidths, selected by one of multiple fixed frequency filters in the modules. The module translates the frequency of the filtered spectral segment to dispose the selected spectral segment about an output frequency to provide the sector's output signal. An optional pilot signal or service channel may be summed with the filtered spectral segment prior to the frequency translation.

Programmable band select and transfer module for local multipoint

Apparatus and method for extending the effective dynamic range of pulse measure and pulse display devices by providing dynamic gain switching, with an associated gain or attenuation coefficient that assumes one of a plurality of two or more values, depending on the instantaneous magnitude of the signal received or upon the choice of an external controller. The amplification path may be one of a plurality of mutually exclusive parallel paths. Alternatively, the amplification path may be a serial combination of an arbitrary subset of a collection of amplification paths. The choice of amplification path may be made automatically by a fast-acting sensor such as a signal comparator or may be made by an external control provided by a human operator or computer and may be overridden by an externally produced control override signal.

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Palo Alto, CA, United States of America

Dieter Scherer