Philip S Marshall

US Patent:

6834180, Dec 21, 2004

Filed:

May 21, 2001

Appl. No.:

09/988101

Inventors:

Philip J. Marshall - Newton MA

Assignee:

Cellco Partnership - Bedminster NJ

International Classification:

H04B 1700

US Classification:

455 6711, 455446, 4554221, 455423, 455424

Abstract:

A system and method that provides radio field strength modeling useful for determining cellular telephone site coverage. The system and method automate sampling procedures, collecting data at various monitoring points within a radio propagation coverage area. The collected data is then interpolated and spurious samples are eliminated. The resultant radio field strength data and respective location data is then analyzed using either a modified Newton second order gradient or a pseudo-exhaustive search method to modeling the field strength for convex and non-convex models, respectively. An iterative approach is used to facilitate the use of model constraints and to mitigate calibration errors attributable to highly correlated variables. For pseudo-exhaustive searches, noise is introduced into the data analysis routines to avoid convergence on local minimum which would otherwise inhibit convergence towards global solutions.

US Patent:

50834630, Jan 28, 1992

Filed:

Feb 7, 1990

Appl. No.:

7/476175

Inventors:

Philip Marshall - Lexington MA
Paul Ford - Maynard MA

Assignee:

M/RAD Corporation - Woburn MA

International Classification:

G01N 2900
B06B 300

US Classification:

73663

Abstract:

A vibration test fixture assembly for releasably securing a test object to the top surface of a sliptable and for rotatably supporting the test object so that the test object can be repositioned between vibration tests without detaching the test object from the fixture. The assembly comprises a bottom plate, a top plate positioned on top of the bottom plate, and a plurality of spring-loaded bearing assemblies between the top and bottom plates for permitting the top plate to rotate relative to the bottom plate except when a downward force of sufficient magnitude to overcome the spring bias of the bearing assemblies is applied to the top plate. The assembly also comprises a plurality of clamps positioned adjacent the top plate for applying a downward force to the top plate sufficient to overcome the spring bias of the bearing assemblies and cause the top plate to engage the bottom plate. The test object is secured to the top plate and the bottom plate is secured to the top surface of a sliptable.

US Patent:

51996901, Apr 6, 1993

Filed:

Jul 30, 1992

Appl. No.:

7/922650

Inventors:

Philip Marshall - Lexington MA

Assignee:

M/RAD Corporation - Woburn MA

International Classification:

F16F 922
F16F 943

US Classification:

267 6425

Abstract:

An active vibration isolation system which has three groups of airbag springs for supporting a load and isolating the load from vibration, together with a servo-valve system for admitting pressurized air to or exhausting pressurized air from each group of the airbag springs, and a damping system for damping movement of the load. The damping system comprises a plurality of pairs of shock absorbers which are mounted in parallel with and adjacent to the airbag springs. The shock absorbers are arranged so as to provide damping for each of the groups of airbag springs in three mutually-orthogonal directions.

US Patent:

52770664, Jan 11, 1994

Filed:

Aug 28, 1992

Appl. No.:

7/937996

Inventors:

Philip Marshall - Lexington MA

Assignee:

M/RAD Corporation - Woburn MA

International Classification:

G01N 2900

US Classification:

73663

Abstract:

A vibration test apparatus for applying simultaneously three equal mutually-orthogonal vibration forces to each of at least two test objects so that each of said forces extends parallel to a corresponding respective one of mutually-orthogonal X, Y and Z axes of each test object. The apparatus comprises a fixture adapted for attachment to a conventional shaker table or a sliptable that has two or four object-supporting plates disposed in a selected angular relationship with the shaker table or sliptable. This angular relationship is selected so that the input vibration force generated by the shaker table is translated into the three equal forces, each of which extends parallel to a corresponding respective one of the three mutually-orthogonal axes of each test object secured to said fixture.

US Patent:

40697061, Jan 24, 1978

Filed:

Nov 18, 1976

Appl. No.:

5/742872

Inventors:

Philip Marshall - Lexington MA
Albert Paul Laber - Revere MA
Ugo Cauteruccio - West Roxbury MA

Assignee:

MRAD Corporation - Woburn MA

International Classification:

G01N 332
B06B 110

US Classification:

73666

Abstract:

A mechanical complex vibration tester is provided which is capable of simultaneously applying a plurality of discrete frequencies to a workpiece positioned on a test surface of the device to simulate random vibration testing. The vibrations may be varied in amplitude and they may be applied in either the vertical or the horizontal direction. Means are provided for isolating the tester from its environment in order to simulate vibration testing in inertial space.

US Patent:

48481602, Jul 18, 1989

Filed:

Oct 25, 1988

Appl. No.:

7/265310

Inventors:

Philip Marshall - Lexington MA
Jeffrey Marshall - Arlington MA
Paul Ford - Arlington MA
Darryl Huttunen - Malden MA

Assignee:

M/RAD Corporation - Woburn MA

International Classification:

G01M 700

US Classification:

73663

Abstract:

A vibration test fixture system for use with a conventional shaker table. The fixture system includes a cube fixture for supporting an object to be tested and a head expander for supporting the cube fixture and for providing a mechanical and vibration transmissive connection between the cube fixture and the shaker table. The fixture system also includes an index mechanism for automatically repositioning the cube fixture relative to the head expander so that the object may be vibration tested along mutually orthogonal axes of the object.

US Patent:

51560518, Oct 20, 1992

Filed:

Jul 16, 1991

Appl. No.:

7/731372

Inventors:

Philip Marshall - Lexington MA

Assignee:

M/RAD Corporation - Woburn MA

International Classification:

G01N 2900

US Classification:

73663

Abstract:

A vibration test apparatus for applying simultaneously three equal vibration forces which extend along three mutually-orthogonal axes to a test object so that each of the forces extends parallel to a corresponding respective one of three mutually-orthogonal axes of the object. The apparatus comprises a fixture adapted for attachment to a conventional shaker table or a sliptable. The fixture supports the test object in selected angular relationship relative to the shaker table or sliptable. This angular relationship is selected so that the input vibration force generated by the shaker table is translated into the three equal forces, each of which extends parallel to a corresponding respective one of the three mutually-orthogonal axes of the test object.