Lgc Wireless, Inc.

Other

University of California

John B Georges

Kam Y Lau

David M Cutrer

Adam L Schwartz

Simon P Yeung

A support system for providing support to a ladder. The support system includes at least one support arm, at least one support leg, at least one support base, and at least one support bracket. The support leg is removably attached to a lower end of the at least one support arm. The support base is coupled to the at least one support leg and has a plurality of ridge on its lower surface. The support bracket is removably attached to the upper end of the at least one support arm. Altogether, the components of the support system are configured to provide support and relative stability to a ladder.

Ladder support apparatus, system, and method

A system and method for transmitting a radio frequency (RF) signal in a RF bandwidth over a low bandwidth medium, e.g., in-building cabling, which has a transmission bandwidth below the RF bandwidth. The system has a unit for intercepting the RF signal and a global reference oscillator for distributing a global reference tone of high stability to the entire system. Local oscillators are controlled by adjustment signals derived from this global reference tone to deliver RF reference tones of high stability required for mixing the RF signal to obtain an intermediate frequency (IF) signal which is fed through the low bandwidth medium. The global reference tone is preferably delivered through the same low bandwidth medium to desired locations, such as remote coverage sites in a network for cellular communications, cordless telephony, local RF communications, interactive multi-media video, high bit-rate local communications. A modified RF signal is generated at the desired location by mixing the IF signal and a local reference signal controlled by the global reference signal.

Distribution of radio-frequency signals through low bandwidth

A system and method is disclosed for distributing a radio frequency (RF) signal within a building structure or other structure not readily transparent to radio frequencies. The RF signal originates at a wireless local loop (WLL) base station and is intercepted by a main antenna on the building structure. The intercepted RF signal, which is contained in a RF bandwidth, is distributed throughout the building structure over a low bandwidth medium, e.g., in-building cabling, which has a transmission bandwidth below the RF bandwidth. In order to accomplish this, the system has a global reference oscillator for distributing a global reference tone of high stability to the entire system. Local oscillators controlled by this global reference tone deliver RF reference tones of high stability required for mixing the RF signal to obtain an intermediate frequency (IF) signal which is fed through the low bandwidth medium to remote sites. At the remote sites the RF signal recovered from the IF signal by mixing with the RF reference tone and re-transmitted, often to WLL communication units. When the WLL base station has a connection to the Public Switch Telephone Network (PSTN), the WLL communication units provide users with wireless telephone services.

Method and system providing RF distribution for fixed wireless local

A system and method for transmitting a radio frequency (RF) signal in a RF bandwidth over a low bandwidth medium, e.g., in-building unshielded twisted pair (UTP) cabling, which has a transmission bandwidth below the RF bandwidth. The system has a unit for receiving the RF signal and a global reference oscillator for distributing a global reference tone of high stability to the entire system. Local oscillators controlled by this global reference tone deliver RF reference tones of high stability required for mixing the RF signal to obtain an intermediate frequency (IF) signal which is fed through the low bandwidth medium to remote sites. A 10 base T cable network, often pre-existing in many building structures, provides a suitable, cost effective low bandwidth medium for such RF communication. Two of the four twisted pair cables of a UTP cable are sufficient to support bi-directional communication. The remaining twisted pair cables are used to control remote site antenna functions or support other types of communication services such as data LAN, video, wired voice, or other wireless services such as PCS or wireless LAN.

Method and system providing increased antenna functionality in a RF

Individual channels are centrally and tunably selected for emission in a distributed wireless communications system. A high-frequency signal received at a central antenna is down-converted such that a selected channel corresponds to a predetermined frequency range. Non-selected channels are filtered out. The selected channel is transmitted to remote locations over commonly available transmission lines, up-converted, and re-emitted. The transmitted channel is chosen by tuning the frequency of the local oscillator used for down-conversion. A high-stability global tuning signal is used to tune and stabilize the local oscillators used for up-conversion. The global tuning signal is generated by frequency-dividing the down-conversion local oscillator signal by a fixed number, while the up-conversion local oscillator signals are generated by frequency-multiplying the global tuning signal by the same fixed number. Phase-locked loops are used for frequency multiplication and stabilization. Applications include cellular communications, cordless telephony, local RF communications, interactive multimedia video, and high bit-rate local communications.

Centralized channel selection in a distributed RF antenna system

A system and method for transmitting a radio frequency (RF) signal in a RF bandwidth over a low bandwidth medium, e.g., in-building cabling, which has a transmission bandwidth below the RF bandwidth. The system has a unit for receiving the RF signal and a global reference oscillator for distributing a global reference tone of high stability to the entire system. Local oscillators are controlled by adjustment signals derived from this global reference tone to deliver RF reference tones of high stability required for mixing the RF signal to obtain an intermediate frequency (IF) signal which is fed through the low bandwidth medium. The global reference tone is preferably delivered through the same low bandwidth medium to desired locations, such as remote coverage sites in a network for cellular communications, cordless telephony, local RF communications, interactive multi-media video, high bit-rate local communications.

The placement of repeater or base station antennas in an in-building or urban wireless RF communications network is optimized using field measurements. Test antennas are placed at a number of sites within the coverage area, and the signal from each test antenna is measured at different locations within the coverage area. The measurement allows the simulation of the coverage provided by different arrangements of antennas. An optimum arrangement can then be chosen. The optimum arrangement of antennas is chosen by maximizing a utility function that depends on the quality of the coverage within the area and on the cost of installing an arrangement. A database of architectural categories (building plans) and measurement results for each category is built by a method of the present invention. A new building is then matched to the closest component categories in the database, thus allowing the optimization of coverage in a coverage area without the measurement of signals from nest antennas in the new building.

Measurement-based method of optimizing the placement of antennas in a RF

The invention discloses a method and an apparatus for optically transmitting a narrow-band optical signal beam having a sub-carrier frequency in the 20 to 300 GHz range. The apparatus has a semiconductor laser with a lasing cavity of length L. The length L preferably ranges from less than 1 mm to 10 mm, thereby defining the round-trip resonance frequency according to the following equation c/2 nL. The apparatus has a signal source for generating an electrical modulating signal having a modulation frequency contained in a narrow band containing the round-trip resonance frequency. An in-coupling means delivers the electrical modulating signal to the semiconductor laser which produces a sub-carrier modulated signal beam whose sub-carrier modulation frequency lies within a response band and corresponds to the modulation frequency. The apparatus further includes a biasing device for providing a biasing voltage for tuning the response band and the sub-carrier modulated signal beam. According to the method of the invention the biasing voltage is used to set the width of the response band and to set a phase shift in the sub-carrier modulated optical signal beam. Varying the biasing voltage thus allows to phase-modulate the sub-carrier modulated optical signal beam.

Apparatus and method for optically transmitting electrical signals in

Disclosed is an optical communication system which uses the self-pulsating frequency of a self-pulsating laser diode as a microwave subcarrier to transmit digital information. The system has a transmitter comprising a self-pulsating laser diode and a modulating mechanism for encoding the laser's self-pulsating microwave sub-carrier. In one embodiment, the modulating mechanism employs frequency-shift keying for digitally encoding the sub-carrier. Furthermore, the optical communication system has a receiver including a photodetector and a signal decoder.

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Berkeley, CA, United States of America

John B Georges