Auto Correlation Spectrometers



The Highly Integrated Full-custom Autocorrelation Spectrometer, or HIFAS, is the next generation digital correlator ASIC developed by Omnisys. Just as the earlier chip generations, it is a full-custom design, processing signals in real time at very high speeds.

The chip is made in a 180 nm BiCMOS process and, unlike the earlier ASICs, both the A/D converter and the correlator are integrated on the same chip. Omnisys has many years of experience developing digital autocorrelation spectrometers, DACS, for space and ground use. Some past projects include spectrometers for the ODIN research satellite and the TeraHertz Limb Sounder, or Telis, mission. The heart of the DACS is the digital correlator back-end that processes signals in real time, at very high speeds. The objective is to develop full-custom ASICs to perform this task at maximum speed using a minimal amount of power.


  • When finished, the chip will set a new world record in auto correlator performance which will open for a range of new possibilities in radiometry on both space and ground.
  • The major advantage of the autocorrelator over other types of spectrometers is that the real-time signal processing can be implemented using relatively simple digital logic, which allows for compact implementations with very high clock speeds and corresponding bandwidths. Or, where that is preferred, low bandwidth and low power implementations.


Autocorrelation spectrometers are employed for radio astronomy and atmospheric research applications, due to their high bandwidth and stability.