Two low-cost phased arrays

In a phased array antenna, the phase shifters (or T/R modules in an active aperture phased array) with their beam-steering control circuitry along with the feed network account for the major hardware cost. This paper presents two antenna array configurations that use simpler feed, simpler phase-shifting and simpler beam-steering control circuitry for realizing low-cost phased arrays. Both are lens configurations. The first one uses a Radant lens, which provides a medium that is loaded with diodes and provides the needed phase shift by switching the diodes on and off. The other configuration employs a ferroelectric dielectric material whose dielectric constant can be varied with an applied DC bias voltage. It is shown that the ferroelectric lens may have further advantages of smaller thickness, simpler beam-steering controls and lower cost     

Study of the Moon and comparative planetology: Problems and perspectives

On the base of the comparative planetologic study of the Moon and terrestrial planets two fundamental features of their history and structure have been established.Firstly, shell-like structure of the terrestrial planets could be understood only in the terms of the heterogeneous accretion theory. At the final stages of major terrestrial planet formation the leading role belonged to the planetosimals of carbonaceous chondritic composition. Secondly, there are two types of the crust on the planetary surface. Their formation are considered to be independent and differing in the geological time. The primary planetary crust of predominantly feldspathic composition is considered to form during the pregeologic period at the final stage of planetary formation due to the impact-explosive processes. The hydrosphere and atmosphere is thought to appear contemporaneously. The basaltic planetary crust is forming later due to the radioactive decay and superimposed on the primary feldspathic crust.     

Jikiken(EXOS-B) observation of siple transmissions

A Japanese magnetospheric satellite Jikiken (EXOS-B) was used to observe Siple transmissions and VLF emissions triggered by the Siple signals. Energetic particle fluxes were also observed at the same time. The first experiments were made during July, August and September in 1979 and the second experiments were made during December in 1979 and January in 1980. The Siple triggered emissions were observed in August. This report reviews the preliminary results.     

Validation of aerosol measurements by the satellite sensors SAM II and SAGE

The satellite sensors SAM II and SAGE have been developing a global data base on stratospheric aerosols since they were launched in October 1978 and February 1979, respectively. The validity of this data base has been tested by numerous comparisons with other measurements made by lidars, balloon-borne particle counters, and aircraft-borne impactors and filters. Because the satellite sensors measure extinction and the correlative sensors measure other properties (e.g., backscatter, number, mass), special techniques are required to convert each measured property to other properties and to quantify conversion uncertainties and measurement uncertainties. Use of these techniques in two major comparative experiments shows that the SAM II and SAGE extinction measurements agree with each other and with values derived from dustsonde, lidar, and filter measurements. In addition, the comparative experiments have highlighted the uncertainties of each type of sensor and stimulated further efforts to reduce these uncertainties.     

Experiments with numerically controlled atomic clocks

Long term timing stability of present atomic clocks can be considerably improved by simple numerical algorithms which correct both the inherent frequency bias and the effects of supply voltage variations and outside temperature. Rubidium units are demonstrated to operate with less than 100 ns errors per week or any sensible longer interval corresponding to relative uncertainties of 10^-13. Often a linear subtraction of frequency offset which can be realized by a microprocessor controlled digital delay line is sufficient. A cesium clock could be run at 10^-15 level, but reliable and reasonable real-time measurement techniques do not yet exist     

Soviet-Indian research of cosmic radiation by high altitude balloons

The report presents some results on the cosmic radiation intensity research carried out with the high-altitude balloons for the period of 1977–1979. The intensity of gamma-radiation with the energy above 40 MeV was measured in two balloon flights at an altitude of 4–7 g/cm² of residual atmosphere in the vicinity of the geomagnetic equator. A temporal analysis of the intensity to discover fluctuations with periods in the range of 4–60 min was made. Quasi-periodic fluctuations of gamma-radiation intensity with 5 min periods, amplitude ～20% and duration of several hours were discovered. Possible mechanisms of such fluctuation appearance are discussed.The report gives the results of measuring downward, upward and horizontal electron fluxes in the vicinity of the equator. The obtained data and the data provided by satellites are compared. The report discusses the prospects of further joint Soviet-Indian research of cosmic gamma-radiation.     

Retrieval of aerosol size distribution from extinction measurements and verification with observations at a tropical station

Aerosol size distributions were retrieved by computing aerosol extinction parameters using extensive measurements of direct solar radiation made in the 0.4 and 0.6 μm wavelengths at Pune with Volz type sunphotometer during winter (November–February), pre-monsoon (March–May), monsoon (June–August) and post-monsoon (September–October) of 1980–1981. The computer aerosol size distributions are compared with the direct measurements made using Anderson eight-stage cascade impactor. There is agreement between the retrieved and measured size distributions. The retrieval method is simple and useful for intensive aerosol measurement programmes.     

Energy deposition rates by charged particles measured during the energy budget campaign

Measurements of the precipitation of electrons and positive ions (in the keV to MeV range) detected aboard eight rockets launched from Northern Scandinavia are reported together with corresponding satellite data. The downgoing integral fluxes indicate the temporal fluctuations during each flight. Height profiles of the energy deposition into the atmosphere at different levels of geomagnetic disturbance are given.     

Instrumentation and data systems for high-time resolution study of space plasma shocks

This paper deals with the principal methods of achieving high-time resolution measurements for the study of fine structure of shocks and other discontinuities in space plasmas. In the measurements of ion energy spectra, we have obtained the time resolution about 1s.In the Soviet-Czechoslovak INTERSHOCK project we will obtain temporal resolution better than 0.1s in the measurement of the main plasma parameters. This will be obtained with the multichannel energy spectrometer and the on-board data acquisition and processing system triggered by the shock signature. This system controls the data sampling rate from some scientific instruments and switches on a high-sampling rate near the shock. The method implies detecting a shock by means of on-board processing of magnetic field and plasma parameters. The algorithm for this detection uses both parameters separately as well as in combinations.