The Astronomy SE question 2SB mixer in radio astronomy? asked in 2014 in its entirety:
In literature about the instrumentation of radio astronomy, I frequently come across a type of mixer described as "2SB". I'm familiar with single-sideband (SSB) and double-sideband (DSB) mixers, but I have never studied a 2SB mixer.
What is a 2SB mixer and how does it compare to a DSB mixer? Ideally, I would also like to know of formal references that directly address the topic for further reading.
is interesting, but its lone 2014 link-only answer in its entirety:
2SB is Dual Sideband, as opposed to DSB - Double Sideband. Here are a couple of papers you might find relevant and interesting:
leaves me still not really understanding the difference between 2SB and DSB mixers nor exactly when one would choose one over the other.
My impression is that DSB mixers suppress the carrier while allowing both sidebands to pass through a single output, while 2SB mixers further separate each sideband to a separate output.
- Is the separation of the two SBs to two outputs the functional difference between 2SB and DSB? If not, what would it be?
- The abstract of the second linked paper says that 2SB mixers' "main advantages being to avoid spectral confusion and to diminish effective system temperature by a factor two with respect to double sideband (DSB) receivers." Is it possible explain in fairly simple terms what that is so?
1Hesper et al. A Sideband-Separating Mixer Upgrade for ALMA Band 9 from the 20th International Symposium on Space Terahertz Technology, Charlottesville, 20-22 April 2009 2A calibrated digital sideband separating spectrometer for radio astronomy applications
2Finger et al. A Calibrated Digital Sideband Separating Spectrometer for Radio Astronomy Applications also available at Pub. Ast. Soc. Pac.