The Deep Space Network (DSN) consists of three complexes located approximately 120 degrees apart on Earth. The three complexes located in Goldstone, California; Madrid, Spain; and Canberra, Australia currently have a 70 meter antenna, one 34 meter High Efficiency (HEF) antenna and one or more 34 meter Beam Wave Guide (BWG) antennas.
The 70 meter antennas were original built as 64 meter antennas in the late 1960's to capture signals from the satellites exploring Venus and Mars. The antennas were upgraded to 70 meters in the mid 1980's when missions were exploring Uranus and Neptune.
The 34 meter High Efficiency (HEF) antennas were built in the 1980's and were the first to support X-band uplink, which was needed for missions exploring the outer planets. The 34 meter Beam Wave Guide (BWG) antennas, the newest of the group, were built in the 1990's. The BWG antenna routes energy between the reflector at the top of the dish and the pedestal room below ground. This allows for multiple feeds and amplifiers at multiple frequencies to be illuminated selectively by a single mirror and remove sensitive electronics from the tipping structure.
Starting in 2002, multiple studies were conducted to determine the most cost effective and technically feasible solution for retiring the 70 meter antennas. These antennas were built over 40 years ago and have begun showing their age. Parts have become difficult to find and maintenance costs are high and continue to increase. These antennas present both physical and technological limitations to potential upgrades needed to support future mission needs.
The Space Communications and Navigation (SCaN) office decided to decommission the 70 meter antennas and replace them with arrays of four 34 meter antennas by 2025. An array of four antennas is easier to maintain and can provide the same/better performance as the 70 meter antenna. The array would consist of four antennas for the receiver function and one 34 meter antenna equipped with an 80 kW for the transmitter function. This plan is called the Deep Space Network (DSN) Aperture Enhancement Project (DAEP).
The first step in the DAEP is to have in three more 34 meter BWG antennas built in Canberra, Australia by 2018. Groundbreaking occurred in February 2010 with US and Australian government officials present.
By 2025, the 70 meter antennas at all three locations will be decommissioned for communications and replaced with the 34 meter BWG antennas arrays. All systems will be upgraded to have X-band uplink capabilities and both X- and Ka-band downlink capabilities.