Radar Doppler spectroscopy of Mars. I.
Radar measurements of Doppler spectra and power reflectivity of Mars interpreted as surface elevation differences between dark and bright areas
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Radar measurements of Doppler spectra and power reflectivity of Mars interpreted as surface elevation differences between dark and bright areas
Closed-loop range-locked radar system successful in range-tracking planet Venus
Description of two antennas, one with a cw transmitter and the other with a maser receiver, used in the jpl venus radar experiment in 1961
Estimates of permittivity and specular points on lunar surface
Two lunar radars used to measure total integrated electron density between Earth and Moon during three nights and two mornings in December 1964
Muhleman radar scattering law indicates that surface of Mercury is similar to Moon in roughness
International conference on scientific radio propagation - time synchronization by radio frequency standard
Radio propagation in atmosphere, and planetary radio and radar astronomical studies
Bistatic radar imaging techniques for study of planetary surfaces
Two-layer atmosphere model of Venus
Radar methods in lunar probing, discussing data obtained from surface soundings
Cryogenic applications to low noise reception development in radio astronomy, planetary radar and communication with deep space probes
The electrostatically controlled membrane mirror (ECMM) is a way to achieve large, very light reflectors for radar, radio astronomy, radiometry, and optical devices. The concept is that of using electrostatic forces to tension a thin conducting membrane and to maintain it in a precision antenna shape. The ECMM is an adaptive structure which maintains surface quality despite errors in construction, irregularities of materials, solar heating, and onboard disturbances. The combination of high gain and low mass makes the ECMM ideally suited for space applications.
The Deep Space Mission System (DSMS) Science Operations Concept describes the vision for enabling the use of the DSMS, particularly the Deep Space Network (DSN) for direct science observations in the areas of radio astronomy, planetary radar, radio science and VLBI.
All contracts are underway for antennas, associated facilities modifications and new transmitters. High risk CPI 100kW klystron and JPL high power uplink microwave components have been designed, prototyped and successfully tested at GDSCC to support the 80kW transmitter implementation and testing at vendor facility. Open issues, which might affect project delivery date, have plans in place or are being created, to maintain DSS-35 Operational Date. There are no known open issues that affect performance. Overall good progress has been made in all areas (procurements, contracts, design and development) and the project is confident that DSS-35 & 36 antennas and the three 80kW Uplink systems will be delivered according to plan.
The recent development of trapped-ion frequency standards, which offer high stability over long time periods, provides us with a potential new method for detecting unseen matter in the outer solar system.
Improvements in power and sensitivity of radar used for astronomy, listing successful planetary observations from 1961 to 1964
The Deep Space Network (DSN) of 1995 might be described as the evolutionary result of 45 years of deep space communication and navigation, together with the synergistic activities of radio science and radar and radio astronomy. But the evolution of the DSN did not just happen - it was carefully planned and created. The evolution of the DSN has been an ongoing engineering activity, and engineering is a process of problem solving under constraints, one of which is technology. In turn, technology is the knowledge base providing the capability and experience for practical application of various areas of science, when needed. The best engineering solutions result from optimization under the fewest constraints, and if technology needs are well anticipated (ready when needed), then the most effective engineering solution is possible. Throughout the history of the DSN it has been the goal and function of DSN advanced technology development (designated the DSN Advanced Systems Program from 1963 through 1994) to supply the technology needs of the DSN when needed, and thus to minimize this constraint on DSN engineering. Technology often takes considerable time to develop, and when that happens, it is important to have anticipated engineering needs; at times, this anticipation has been by as much as 15 years. Also, on a number of occasions, mission malfunctions or emergencies have resulted in unplanned needs for technology that has, in fact, been available from the reservoir of advanced technology provided by the DSN Advanced Systems Program. Sometimes, even DSN engineering personnel fail to realize that the organization of JPL permits an overlap of DSN advanced technology activities with subsequent engineering activities. This can result in the flow of advanced technology into DSN engineering in a natural and sometimes almost unnoticed way. In the following pages, we will explore some of the many contributions of the DSN Advanced Systems Program that were provided to DSN Engineering and Implementation. These contributions are, for the most part, unique capabilities that have met the requirements of flight projects for 45 years. These unique capabilities include not only the world's best deep-space communications system, but also outstanding competency in the fields of radio metric measurement, radar and radio astronomy, and radio science.