KEVIN T ANDERSON
Electrician in Plano, TX

2001001, Aug 9, 2001

Mar 11, 1998

09/038518

MONTY M. SHELTON - CARROLLTON TX, US
KEVIN ANDERSON - PLANO TX, US

H04Q001/00, H04B001/00

340/825490, 340/005640

A wireless personnel locator system includes a plurality of low power, compact, radio frequency (RF) transmitters adapted to continuously transmit narrow band modulated or spread spectrum modulated signals, including a transmitter identification code or serial number. Designated public areas such as retail merchant complexes, exhibit halls, and entertainment complexes have identified RF receivers at designated locations, such as entrance and exit portals, for receiving transmitter signals and transmitting related information to a control center processing unit which correlates the received signals with a subscriber or authorized person for each of the transmitters. The transmitters may be incorporated in easily carried devices such as key chain fobs, integrated into pager devices or cellular phones or encapsulated in an elastic band worn by the user. The processing unit may be in communication with a security department for providing information regarding the whereabouts of persons about to make unauthorized exits from or entrances into particular areas. A communication unit may be available to subscribers at particular locations in the designated areas for accessing information as to the whereabouts of a person carrying a transmitter.

4658440, Apr 14, 1987

Jul 27, 1984

6/635093

Anthony M. Pavio - Plano TX
Kevin J. Anderson - Plano TX

Texas Instruments Incorporated - Dallas TX

H04B 126

455324

A single balanced self-oscillating dual gate FET mixer includes two dual-gate FETs, a dielectric resonator, two transmission lines inductively coupled to the resonator and connected to the second gates of the two dual-gate FETs, an RF input, two RF matching networks connected to the RF input and to the first gates of the two dual-gate FETs, a 180 degree power combiner, and two IF matching networks connected between the drains of the two dual-gate FETs and to the power combiner. The output of the power combiner is the IF output. The two dual-gate FETs comprise the active device of the oscillator and are used as a nonlinear mixing amplifier. The resonator network provides series feedback with gate 1 of each FET to produce the local oscillator signal and controls the frequency of oscillation. Single balancing of the local oscillator signals injected into gate 1 of each FET is accomplished by mutually coupling the resonator to the two transmission lines, thus providing the required 180 degree phase difference between signals. Finally, the 180 degree power combiner incorporates the phase change necessary for constructive addition of the IF signals originating from each drain port of each FET.