International Business Machines Corporation

Peracom Networks, Inc.

William Burrell Nunnery

Mark John Lawrence

Charles R Hoffman

Modest M Oprysko

Alexander G MacInnis

Saila Ponnapalli

John M Dinwiddie

Brian Scott Oakley

Jack S Chorpenning

Frank J Canora

Apparatus for distributing radio frequency (RF) modulated broadcast television signals from a broadcast signal source to networked appliances connected to the source through a plurality of single conductor coaxial cables, simultaneously with distributing unmodulated digital signals and RF modulated video signals exchanged between the networked appliances over the same network coaxial cables.

Entertainment and computer coaxial network and method of distributing signals therethrough

A radio frequency (RF) local area network (LAN) adapter card for a personal computer conforms to the Personal Computer Memory Card International Association (PCMCIA) standard 2.0 (extended), providing a credit-card sized RF LAN communications terminal that plugs into the side of a personal computer, a laptop computer, a palmtop computer, and the like. The RF LAN adapter card includes a minimum height, broadband integrated antenna that provides a vertically polarized RF signal with good horizontal range. The combination of the antenna and its surrounding radome provide a high gain, omnidirectional radiation pattern that overcomes the parasitic distortions imposed by the close proximity of the personal computer housing. The adapter card housing includes internal RF shielding structures that shield the antenna from noise radiated by radio frequency signal circuits within the housing. A conductive adhesive coating is provided on the conductive layer of the ground plane of the antenna, for mechanically and electrically connecting the ground plane to the adapter card housing. This enables the antenna to be assembled to the housing at a later time after testing of the internal circuits in the adapter card.

Radio frequency LAN adapter card structure and method of manufacture

Radio frequency local area network adapter card structure and method of

The antenna is a hybrid microstrip and reflector antenna having a planar patch antenna mounted to an upper surface of an insulated planar substrate. The substrate is coupled to a ground plane by one or more insulated couplers so as to form an airgap therebetween. A coaxial cable connectable to a transceiver is coupled to the bottom surface of the ground plane at the outer conductor thereof and the inner conductor is coupled to a feed pin which passes through the ground plane and protrudes through the surface of the patch. The feed pin is secured to the patch by soldering.

High gain broadband planar antenna

A method and apparatus for controlling a power supply which includes a power transformer having primary and secondary windings and switching transistors for switching current through the windings. The apparatus includes circuitry for generating a composite signal representative of the flux and magnetizing current (I.sub.m) in the power transformer. The composite signal is correlated with a multiphase clocking signal to generate a pulsewidth modulated (PWM) signal which is used to drive the switching transistors.

Flux centering and power control for high frequency switching power

The invention covers an amplifier circuit in which the output is limited in either polarity. Normally, a part of the output voltage is fed back to the input to maintain linearity but when the output reaches a maximum or minimum value, any further departure is amplified and fed back to the input circuit to neutralize the part of input signals which is outside of the range to be amplified. The feedback amplifier can be designed to initiate limiting at any desired output voltages and the positive and negative output limit voltages can be asymmetric with respect to the quiescent output voltage.

Growing community of inventors

Cary, NC, United States of America

William Burrell Nunnery