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Rice, J. S.

Publications and source records attributed to Rice, J. S..

An interferometer-based phase control system

A system for focusing and pointing the SPS power beam is discussed. The system is ground based and closed loop. One receiving antenna is required on earth. A conventional uplinked data channel transmits an 8-bit phase error correction back to the SPS for sequential calibration of each power module. Beam pointing resolution is better than 140 meters at the rectenna.

Ott, J. H.

A sonic satellite power system microwave power transmission simulation

A simulator is described which generates and transmits a beam of audible sound energy mathematically similar to the SPS power beam. The simulator provides a laboratory means for analysis of ground based closed loop SPS phase control and of ionospheric effects on the SPS microwave power beam.

Ott, J. H.

Sonic simulation of the SPS power beam

A Satellite Power System Microwave Transmission Simulator is described. The simulator generates and transmits a beam audible sound energy which is mathematically similar to the microwave beam which would transmit energy to Earth from a Solar Power Satellite. This allows areas such as power beam formation to be studied in a laboratory environment.

Ott, J. H.

Beat frequency interference pattern characteristics study

The frequency spectra and corresponding beat frequencies created by the relative motions between multiple Solar Power Satellites due to solar wind, lunar gravity, etc. were analyzed. The results were derived mathematically and verified through computer simulation. Frequency spectra plots were computer generated. Detailed computations were made for the seven following locations in the continental US: Houston, Tx.; Seattle, Wa.; Miami, Fl.; Chicago, Il.; New York, NY; Los Angeles, Ca.; and Barberton, Oh.

Ott, J. H.

A theoretical study of microwave beam absorption by a rectenna

The results of a theoretical study of microwave beam absorption by a Rectenna are given. Total absorption of the power beam is shown to be theoretically possible. Several improvements in the Rectenna design are indicated as a result of analytic modeling. The nature of Rectenna scattering and atmospheric effects are discussed.

Ott, J. H.

A theoretical study of microwave beam absorption by a Rectenna

The results of a theoretical study of microwave beam absorption by a rectenna is given. Total absorption of power beam is shown to be theoretically possible. Several improvements in the rectenna design are indicated as a result of analytic modeling. The nature of rectenna scattering and atmospheric effects is discussed.

Ott, J. H.

An interferometer based phase control system

An interferometer based phase control system for focusing and pointing the solar power satellite (SPS) power beam is discussed. The system is ground based and closed loop. One receiving antenna is required on Earth. A conventional uplink data channel transmits an 8 bit phase error correction back to the SPS for sequential calibration of each power module. Beam pointing resolution is better than 140 meters at the rectenna.

Ott, J. H.

A power satellite sonic simulator

A simulator is described which generates and transmits a beam of audible sound energy mathematically similar to the solar power satellite (SPS) power beam. The simulator provides a laboratory means for analysis of ground based closed loop SPS phase control and of ionospheric effects on the SPS microwave power beam.

Ott, J. H.

A theoretical study of microwave beam absorption by a rectenna

The rectenna's microwave power beam absorption limit was theoretically confirmed by two mathematical models descriptive of the microwave absorption process; first one model was based on the current sheet equivalency of a large planar array above a reflector and the second model, which was based on the properties of a waveguide with special imaging characteristics, quantified the electromagnetic modes (field configurations) in the immediate vicinity of a Rectenna element spacing which permit total power beam absorption by preventing unwanted modes from propagating (scattering) were derived using these models. Several factors causing unwanted scattering are discussed.

Ott, J. H.

An interferometer-based phase control system

A system for focusing and pointing the SPS power beam is discussed. The system is ground based and closed loop. One receiving antenna is required on Earth. A conventional uplink data channel transmits an 8-bit phase error correlation back to the SPS for sequential calibration of each power module. Beam pointing resolution is better than 140 meters at the Rectenna.

Ott, J. H.

A sonic satellite power system microwave power transmission simulator

A simulator which generates and transmits a beam of audible sound energy mathematically similar to the SPS power beam is described. The simulator provides a laboratory means for analysis of ground based closed loop SPS phase control and of ionospheric effects on the SPS microwave power beam.

Ott, J. H.

An investigation of the compressive strength of Kevlar 49/epoxy composites

Tests were performed to evaluate the effect of a wide range of variables including matrix properties, interface properties, fiber prestressing, secondary reinforcement, and others on the ultimate compressive strength of Kevlar 49/epoxy composites. Scanning electron microscopy is used to assess the resulting failure surfaces. In addition, a theoretical study is conducted to determine the influence of fiber anisotropy and lack of perfect bond between fiber and matrix on the shear mode microbuckling. The experimental evaluation of the effect of various constituent and process characteristics on the behavior of these unidirectional composites in compression did not reveal any substantial increase in strength. However, theoretical evaluations indicate that the high degree of fiber anisotropy results in a significant drop in the predicted stress level for internal instability. Scanning electron microscope data analysis suggests that internal fiber failure and smooth surface debonding could be responsible for the measured low compressive strengths.

Kulkarni, S. V.

An investigation of the compressive strength of PRD-49-3/Epoxy composites

The development of unidirectional fiber composite materials is discussed. The mechanical and physical properties of the materials are described. Emphasis is placed in analyzing the compressive behavior of composite materials and developing methods for increasing compressive strength. The test program for evaluating the various procedures for improving compressive strength are reported.

Kulkarni, S. V.