Small Deep Space Transponder

From Wikipedia, the free encyclopedia
  (Redirected from Small deep space transponder)
Jump to: navigation, search
Small Deep Space Transponder

The Small Deep Space Transponder is a transponder designed by JPL specifically for deep space probes.[1] It unifies a number of communication functions - receiver, command detector, telemetry modulator, exciters, beacon tone generator, and control functions - into one 3-kg package. The SDST is designed to handle X band uplink and both X band and Ka band downlink. JPL estimates that performing the same functions with separate units (as was done previously) requires over twice the mass and 4 or 5 individual subassemblies.[2]

Functions[edit]

The capabilities of the SDST include:[3]

  • X-band receiver/downconverter capable of carrier tracking at or below −156 dBm.
  • Command detector unit function.
  • Telemetry modulation function.
  • X- and Ka-band exciters.
  • Beacon mode operation.
  • Coherent and noncoherent operation choice.
  • X- and Ka-band ranging.
  • Differential one-way ranging (DOR) for both X-band and Ka-band.
  • Command and Data Handling (C&DH) communication via MIL-STD-1553.
  • Data interface via EIA-422 (also known as RS-422).
  • External ports for temperature sensors.
  • External port for an analog signal.

Missions[edit]

SDST has been used in the following missions:[4]

As do many tightly constrained, high-performance systems, the SDST has a number of idiosyncrasies in operation.[5] However, as the Dawn telecom 'lessons learned' section points out, the use of common hardware such as the SDST allows knowledge of these characteristics from previous projects.[5]

References[edit]

  1. ^ Sam Zingales. "Small Deep-Space Transponder Development". JPL. 
  2. ^ "Technology: SMALL DEEP SPACE TRANSPONDER". JPL. 
  3. ^ Chien-Chung Chen, Shervin Shambayati, Andrew Makovsky, F. H. Taylor, Martin I. Herman, Samuel H. Zingales, Carl Nuckolls, Keith Siemsen. "Small Deep Space Transponder (SDST) DS1 Technology Validation Report". 
  4. ^ "NMP (New Millennium Program) Scorecard". 
  5. ^ a b c Jim Taylor (August 2009). "Dawn Telecommunications". JPL. 
  6. ^ Jim Taylor, Stan Butman, Chad Edwards, Peter Ilott, Richard Kornfeld, Dennis Lee, Scott Shaffer, Gina Signori (August 2010). "Phoenix Telecommunications". JPL. 
  7. ^ Andre Makovsky, Peter Ilott, Jim Taylor (2009). "Mars Science Laboratory Telecommunications System Design". JPL.