The efficiency and noise temperature characteristics of the DSN 64 m antenna network prior to its upgrading to 70 m configuration are documented. The DSS 14 (Goldstone, California) is the last of the three large antennas to be upgraded, and the test results presented document its performance just prior to its downtime during the end of 1987. Antenna area efficiency was found to be somewhat higher at DSS 14 than at DSS 43 (Australia) and DSS 63 (Spain). The peak X-band efficiency was determined to be 49.8 percent (without atmosphere), compared with 45.4 and 45.1 percent for DSS 43 and DSS 63, respectively. The X-band zenith system noise temperature was found to be 1 to 3 Kelvins higher than at the other two stations, depending on which maser was chosen for the measurements. Ascribing efficiency differences to small-scale antenna surface roughness, DSS 14 may be regarded as having a 1.5 to 1.6 mm rms surface as compared to the other two antennas with 1.7 to 1.8 mm rms surfaces.

/pdf/dss-14-64-meter-antenna-s-and-x-band-efficiency-and-system-4jzqtmzl13.pdf

DSS 14 64-meter antenna S- and X-band efficiency and system noise temperature calibrations, September 1987

Over the last 7 years, more than 35,000 correlated flux density observations, accurate to ∼20 percent, of 290 extragalactic radio sources have been conducted at S-band (2.3 GHz) and X-band (8.4 GHz) using the MkIII very long baseline interferometry (VLBI) system of the Deep Space Network (DSN). These ongoing observations, with typical 5σ detection limits of ∼45 mJy at S-band and ∼30 mJy at X-band, have been taken as part of the high-accuracy reference frame catalog required for the VLBI tracking of Galileo, Cassini, and future missions. A total flux density catalog, also accurate to ∼20 percent, with 1440 observations on 190 sources and typical detection limits of 0.8 Jy at S-band and 0.4 Jy at X-band, also has been created. We present here summary tables of these observations and discuss a few examples of variable sources.

/pdf/vlbi-dsn-flux-density-observations-from-1989-to-1996-of-290-imk29p3z2r.pdf

VLBI DSN Flux Density Observations From 1989 to 1996 of 290 Extragalactic Radio Sources

Correlated flux densities of extragalactic radio sources in the very long baseline interferometry (VLBI) astrometric catalog are required for the VLBI tracking of Galileo, Mars Observer, and future missions. A system to produce correlated and total flux density catalogs was developed to meet these requirements. A correlated flux density catalog of 274 sources, accurate to about 20 percent, was derived from more than 5000 DSN VLBI observations at 2.3 GHz (S-band) and 8.4 GHz (X-band) using 43 VLBI radio reference frame experiments during the period 1989-1992. Various consistency checks were carried out to ensure the accuracy of the correlated flux densities. All observations were made on the California-Spain and California-Australia DSN baselines using the Mark 3 wideband data acquisition system. A total flux density catalog, accurate to about 20 percent, with data on 150 sources, was also created. Together, these catalogs can be used to predict source strengths to assist in the scheduling of VLBI tracking passes. In addition, for those sources with sufficient observations, a rough estimate of source structure parameters can be made.

https://ntrs.nasa.gov/api/citations/19930009720/downloads/19930009720.pdf

Correlated Flux Densities From VLBI Observations With the DSN

The X- and S-band system operating noise temperatures of the Deep Space Network (DSN) 70-m antennas are presented. Models of atmosphere and ground noise temperature contributions, as they affect the antenna calibrations, are given for future use in telecommunications link modeling. The measured 70-m antenna network gain/system noise temperature (G/T) performance is presented. Compared with the earlier 64-m antenna network, G/T improvements of from 1.8 dB to 2.5 dB, depending on elevation angle, were achieved. G/T comparisons are made with the DSN/Flight Project Design Handbook and the Voyager telecommunications design control table. Actual Voyager telecommunications link performance is compared with predictions made by TPAP (the Voyager telecommunications prediction and analysis program) and with measured performance of the individual 70-m antennas. A modification in the use of antenna gain, system noise temperature, and atmospheric attenuation in existing telecommunications design control tables is suggested.

P. H. Richter

Papers

DSN 70-meter antenna X- and S-band calibration. Part 2: System noise temperature measurements and telecommunications link evaluation