MICHAEL J. LA FEMINA, MD
Osteopathic Medicine at De Soto Ave, Woodland Hills, CA

4575693, Mar 11, 1986

May 9, 1983

6/492513

Michael de la Chapelle - Canoga Park CA
Frank A. Wilhelmi - Simi CA

Hughes Aircraft Company - El Segundo CA

H04B 304, H03K 507

333 20

A pulse modulator including a pulse forming network comprising a multiple section ladder network of series inductors and shunt capacitors. The series inductors are flat, spiral inductors etched on microstrip. The pulse forming network is charged negatively through an IMPATT diode, and is switched to ground by a set of p-channel VMOS power FETs. By switching off the FET switches before the pulse forming network is completely dicharged, the fall time of the current pulse is reduced. The shape of the current pulse can be adjusted by varying the impedance of the section or sections of the pulse forming network whose position in the network corresponds to the position in the current pulse which it is desired to change. The variation in impedance is realized by bringing metallic slugs, mounted in the housing of the pulse forming network, into proximity with the flat, spiral inductors.

4832433, May 23, 1989

Dec 31, 1986

6/948339

Michael de La Chapelle - Canoga Park CA
Hui-Pin Hsu - Canoga Park CA
Gib F. Lewis - Manhattan Beach CA
John E. Mantele - Laguna Niguel CA

Hughes Aircraft Company - Los Angeles CA

G02B 642

350 9615

The corporate feed network employs light emitting opto-electronic components, such as laser diodes (12), connected together in a string (14) for distributing RF, microwave, MMW, digital signals, and pulse modulated light. Each diode provides two ports or facets which are coupled to optical fibers (16, 18) to connect to an active phased array antenna, for example. The diodes are selected in number and impedance to provide a good wideband impedance match to the RF/microwave/MMW/digital driving source. Multiple series strings of diodes may be employed, connected in parallel for larger corporate feed structures.

5029240, Jul 2, 1991

Jun 26, 1989

7/371567

Michael de La Chapelle - Canoga Park CA
Hui-Pin Hsu - Canoga Park CA

Hughes Aircraft Company - Los Angeles CA

H04B 1006

455619

The optical receiver has a photodiode (10) which is reverse biased by a voltage supply (14). The voltage supply provides a variable bias voltage determined by a control unit (16) and the photodiode is matched to the load (22) by an impedance matching circuit (12). The photodiode exhibits large capacitance changes over a range of bias voltages and may be implemented using a Schottky barrier or P. sup. + N photodiode. By changing the bias voltage, the photodiode capacitance changes to vary the tuned frequency of the receiver. The matching circuit cancels the reactive component of the photodiode impedance and matches the resistive component to the load. The photodiode may have a doping profile in which an intrinsic or lightly doped region of width greater than the average photon penetration depth is located next to the junction. After the intrinsic region, the doping profile may be selected to achieve linear tuning. This doping profile gives linear tuning without sacrificing photodiode conversion efficiency.

5013971, May 7, 1991

Jul 21, 1989

7/360491

Michael de La Chapelle - Canoga Park CA

Hughes Aircraft Company - Los Angeles CA

H05B 4136, H03F 304

315149

The optical power emitted from a light energy producing diode is stabilized over temperature using a simple bias circuit consisting of a voltage source with a series resistance or a current source with a shunt resistance. The bias circuit resistance is equal to the slope of the bias line formed by the constant optical power bias points of the diode plotted on a voltage versus current graph. The voltage source or current source value in the bias circuit is equal to the zero current or zero voltage intercept value, respectively.

5055810, Oct 8, 1991

Aug 29, 1990

7/576140

Michael de La Chapelle - Canoga Park CA
Hui-Pin Hsu - Canoga Park CA

Hughes Aircraft Company - Los Angeles CA

H01P 115

333262

The RF/microwave switch/modulator uses an optically controlled diode 20. The reactance of the diode may be varied by varying the illumination intensity. In this fashion, the photodiode in conjunction with an external circuit can switch or modulate a microwave signal by varying the reactance of the diode using a laser light source or the like. The bias voltage may be varied to electronically tune the diode so that the microwave frequency of operation can be electronically controlled.