DEREK P FITZGERALD
Accountancy in Lincoln Center, MA
License number
Massachusetts 25091
Issued Date
Oct 18, 2007
Expiration Date
Jun 30, 2017
Type
Certified Public Accountant
Address
Address
Lincoln Center, MA 01773
Professional information
Voltage Variable Attenuator
US Patent:
5349312, Sep 20, 1994
Filed:
May 28, 1993
Appl. No.:
8/068911
Inventors:
Steven E. Huettner - Billerica MA
Maureen A. Daly - Pelham NH
Derek J. Fitzgerald - Lincoln MA
Maureen A. Daly - Pelham NH
Derek J. Fitzgerald - Lincoln MA
Assignee:
Raytheon Company - Lexington MA
International Classification:
H01P 122
US Classification:
333 81A
Abstract:
A voltage variable attenuator is described including a quadrature hybrid coupler having an input port, an output port, a first reflective port and a second reflective port. The voltage variable attenuator further includes a first and a second impedance network, the first impedance network connected to the first reflective port of the quadrature hybrid coupler, the second impedance network connected to the second reflective port of the quadrature hybrid coupler, each impedance network including a first RF propagation network having a first end connected to the respective reflective port of the quadrature hybrid coupler. Each impedance network further includes a second end of the first RF propagation network connected to a field effect transistor having a drain electrode, a source electrode and a gate electrode, the drain electrode connected to the second end of the first RF propagation network. Completing each impedance network is a second RF propagation network having a first end connected to the source electrode and a second electrode connected to a ground through a plated via hole.