Citation
Abstract
NASA is interested in using the technique of arraying smaller-diameter antennas to increase effective aperture in order to replace aging monolithic 70-m structures of the Deep Space Network (DSN). Downlink arraying using the 34-m-diameter and 70-m-diameter antennas is routinely performed by the DSN for certain missions. Future scenarios will include extending the technique to uplink arraying where a downlink signal may not necessarily be available for phasing the signals at the individual stations of the array. Atmospheric decorrelation degrades the arrayed signal, and it becomes more severe in high-frequency bands such as the uplink allocations near 34 GHz and 40 GHz. This article provides sufficient information for a flight project to statistically account for this effect in the design of a telecommunications link involving arrayed antennas in the DSN. The annual and monthly cumulative distributions of expected phasing loss have been derived from the data acquired by site test interferometers at the Goldstone and Canberra complexes. These phasing loss statistics have then been mapped into two-element and three-element amplitude fade (dB loss) statistics referenced at the DSN uplink frequencies of 7.15 GHz and 34.5 GHz and at an elevation angle of 20 deg for both Goldstone and Canberra DSN sites. We also discuss validation tests that ensure the integrity of the data.
Details
- Volume
- 42-196
- Published
- February 15, 2014
- Pages
- 1–23
- File Size
- 1.3 MB