<p>When determining the retrieval algorithm for a spectrometer that will be built, it is first done on highly mathematical software platforms.  The software allows to the best curve approximation fitting equations to be derived (across all detected wavelengths) that will work for the proposed optics.  This is important because the diffracted light that is detected will interfere with itself very uniquely, depending on the geometry of your optical setup.   The data from the spectrometer's detector needs to be interpreted with a good curve fitting function so that you can get good wavelength resolution from your instrument.  </p>

<p>When building a spectrometer for operational use on a satellite, it is ideal to be able to process the retrieval algorithm using hardware, rather than software.  The hardware processor allows real time function that isn't dependent on an operating system that requires lot's of computational overhead.  So, you build a breadboard that you can connect to your spectrometer so that your retrieval algorithm is processed using integrated circuits that can be programmed.  You essentially hard-code your algorithm into hardware.</p>

<p>Search for "breadboard spectrometer" in Google and you will find many examples.  </p>

<p>Now, to answer your question.  A breadboard algorithm is developed using software that is used to help engineer the actual breadboards to be built in the future.  The software allows you to predict the response of your proposed circuitry to the spectrometer detector without having to actually build the breadboard yet.  Once your breadboard algorithm is setup properly (confirmed by testing the software version of your needed hardware) you can go about building the actual breadboard spectrometer model.</p>

<p>Once a breadboard spectrometer model is built and passes quality control checks, you can evaluate the spectrometer performance and see if its worth optimizing and fabricating a standalone instrument payload that can be deployed in the field (or in space).</p>

CC BY-SA 3.0
2017-03-30T01:12:55.247Z
I have no clue if this is correct or not :-)  It sounds very interesting and I should read up on it more.
gerrit
CC BY-SA 3.0
2017-03-30T03:55:16.257Z
I could do a better job of describing the different software used, but I think it gives the jist of what you are asking about.
f.thorpe
CC BY-SA 3.0
2017-03-29T23:23:50.603Z
2017-03-30T04:07:20.270Z
2017-03-30T04:07:20.270Z
f.thorpe
<p>This question would probably be better suited to engineering or electronic/electrical engineering.</p>

<p>My guess is that the breadboard will be used to test potential electronic circuits &amp; being for ESA, possibly electronic circuits for satellites or probes.</p>

<p>Breadboards can be used to test different connection geometries of electronic components. These would need to be optimized for weight &amp; energy consumption, particularly if they are to be launched into outer space. Software (algorithms) exist where this can be done using a virtual breadboard rather than a physical one</p>

CC BY-SA 3.0
2017-03-30T08:28:36.933Z
Are you sure? The contexts I could find make no mention of electronics or electrical engineering, but seem to be about algorithm development only.
gerrit
CC BY-SA 3.0
2017-03-30T02:53:59.087Z
2017-03-30T02:53:59.087Z
Fred
<p>In a recent <a href="https://www.lists.rdg.ac.uk/archives/met-jobs/2017-03/msg00090.html" rel="nofollow noreferrer">met-jobs job posting</a> (<a href="http://www.esa.int/content/download/375286/16878272/file/RF-ECSAT(2016)001%20Rev2.pdf" rel="nofollow noreferrer">different version here</a>) for a researcher with a background in <em>climatology/meteorology/hydrology or
environmental sciences</em>, I saw the phrase <em>breadboard retrieval algorithm</em> (emphasis mine):</p>

<blockquote>
  <p>Sentinel-4 Retrieval: This Research Fellow Opportunity aims at
  testing of <strong>breadboard retrieval algorithms</strong>. It is foreseen that
  synthetic satellite data, and possibly also real measurements data from
  airborne and satellite sensors will be used for this purpose. The
  activity might also cover the exploration of alternative retrieval
  approaches depending on the expertise and skills of the candidate.</p>
</blockquote>

<p>What is a breadboard (retrieval) algorithm?  Google Search yields precious few results, mostly from ESA.  Another usage I found</p>

<p><a href="http://envisat.esa.int/workshops/validation_12_02/proceedings/meris/20_albert.pdf" rel="nofollow noreferrer">Albert, Preusker, and Fischer (2012), ENVISAT workshop</a>:</p>

<blockquote>
  <p>Originally, three <strong>breadboard algorithms</strong> were developed at the 
  Freie Universität Berlin, and the knowledge for their creation 
  was  transferred  to  ESA  /  Bomem  for  the  creation  of  the  ESA  algorithms.  In  the  meantime,  the  original  look-up  table approach was replaced for the breadboard algorithms by the use of artificial neural networks, which significantly eases the interpolation  of  the  simulation  results  onto  the  actual  viewing geometry.</p>
</blockquote>

<p>Wikipedia tells me that, in electronics, a <a href="https://en.wikipedia.org/wiki/Breadboard" rel="nofollow noreferrer">breadboard</a> is <em>a construction base for prototyping electronics</em>.  The details of the article do not appear relevant for the algorithm usage, but it makes me guess that the meaning of breadboard is related to prototyping.  However, from context, it is clear that the job ad or the ENVISAT paper has nothing to do with electronics.</p>

<p>What does breadboard mean in the context of Earth observation retrieval algorithm development (which are the only contexts I could find)?  Is it simply a synonym for prototype, or does it have a different meaning?</p>

CC BY-SA 3.0
2017-03-30T08:14:00.653Z
@gansub All uses I have been able to find is about retrieving geophysical parameters from satellite observations.  The quote is straight from the met-jobs mailing list.
gerrit
CC BY-SA 3.0
2017-03-30T08:25:49.563Z
@gansub I disagree.  ESA are using the phrase breadboard algorithm in a use unrelated to electronics, specifically in the context of the retrieval of geophysical parameters.  [Remote sensing is ontopic](https://earthscience.meta.stackexchange.com/a/1403/6) and retrieval is an integral part of it.   I acknowledge that this may not have been sufficiently clear in my initial question formulation.  I'll let the community decide, though.
gerrit
CC BY-SA 3.0
2017-03-30T23:41:30.143Z
Remote sensing of the Earth is on-topic
f.thorpe
<remote-sensing><terminology>
What is a breadboard (retrieval) algorithm in the context of geophysical satellite retrievals/remote sensing?
gerrit
# What is a breadboard (retrieval) algorithm in the context of geophysical satellite retrievals/remote sensing?

(Asked by: username_0 on 2017-03-29)

In a recent [met-jobs job posting](https://www.lists.rdg.ac.uk/archives/met-jobs/2017-03/msg00090.html) ([different version here](http://www.esa.int/content/download/375286/16878272/file/RF-ECSAT(2016)001%20Rev2.pdf)) for a researcher with a background in *climatology/meteorology/hydrology or
environmental sciences*, I saw the phrase *breadboard retrieval algorithm* (emphasis mine):

> Sentinel-4 Retrieval: This Research Fellow Opportunity aims at
> testing of **breadboard retrieval algorithms**. It is foreseen that
> synthetic satellite data, and possibly also real measurements data from
> airborne and satellite sensors will be used for this purpose. The
> activity might also cover the exploration of alternative retrieval
> approaches depending on the expertise and skills of the candidate.

What is a breadboard (retrieval) algorithm? Google Search yields precious few results, mostly from ESA. Another usage I found

[Albert, Preusker, and Fischer (2012), ENVISAT workshop](http://envisat.esa.int/workshops/validation_12_02/proceedings/meris/20_albert.pdf):

> Originally, three **breadboard algorithms** were developed at the
> Freie Universität Berlin, and the knowledge for their creation
> was transferred to ESA / Bomem for the creation of the ESA algorithms. In the meantime, the original look-up table approach was replaced for the breadboard algorithms by the use of artificial neural networks, which significantly eases the interpolation of the simulation results onto the actual viewing geometry.

Wikipedia tells me that, in electronics, a [breadboard](https://en.wikipedia.org/wiki/Breadboard) is *a construction base for prototyping electronics*. The details of the article do not appear relevant for the algorithm usage, but it makes me guess that the meaning of breadboard is related to prototyping. However, from context, it is clear that the job ad or the ENVISAT paper has nothing to do with electronics.

What does breadboard mean in the context of Earth observation retrieval algorithm development (which are the only contexts I could find)? Is it simply a synonym for prototype, or does it have a different meaning?

**Tags:** remote-sensing, terminology

> **Comments:**
> **username_0**: @gansub All uses I have been able to find is about retrieving geophysical parameters from satellite observations.  The quote is straight from the met-jobs mailing list.  
> **username_0**: @gansub I disagree.  ESA are using the phrase breadboard algorithm in a use unrelated to electronics, specifically in the context of the retrieval of geophysical parameters.  [Remote sensing is ontopic](https://earthscience.meta.stackexchange.com/a/1403/6) and retrieval is an integral part of it.   I acknowledge that this may not have been sufficiently clear in my initial question formulation.  I'll let the community decide, though.  
> **username_1**: Remote sensing of the Earth is on-topic  

---

## 2 answers

### Answer by username_1 on 2017-03-29. Score: 4

When determining the retrieval algorithm for a spectrometer that will be built, it is first done on highly mathematical software platforms. The software allows to the best curve approximation fitting equations to be derived (across all detected wavelengths) that will work for the proposed optics. This is important because the diffracted light that is detected will interfere with itself very uniquely, depending on the geometry of your optical setup. The data from the spectrometer's detector needs to be interpreted with a good curve fitting function so that you can get good wavelength resolution from your instrument.

When building a spectrometer for operational use on a satellite, it is ideal to be able to process the retrieval algorithm using hardware, rather than software. The hardware processor allows real time function that isn't dependent on an operating system that requires lot's of computational overhead. So, you build a breadboard that you can connect to your spectrometer so that your retrieval algorithm is processed using integrated circuits that can be programmed. You essentially hard-code your algorithm into hardware.

Search for "breadboard spectrometer" in Google and you will find many examples.

Now, to answer your question. A breadboard algorithm is developed using software that is used to help engineer the actual breadboards to be built in the future. The software allows you to predict the response of your proposed circuitry to the spectrometer detector without having to actually build the breadboard yet. Once your breadboard algorithm is setup properly (confirmed by testing the software version of your needed hardware) you can go about building the actual breadboard spectrometer model.

Once a breadboard spectrometer model is built and passes quality control checks, you can evaluate the spectrometer performance and see if its worth optimizing and fabricating a standalone instrument payload that can be deployed in the field (or in space).

> **Comments:**
> **username_0**: I have no clue if this is correct or not :-)  It sounds very interesting and I should read up on it more.  
> **username_1**: I could do a better job of describing the different software used, but I think it gives the jist of what you are asking about.  

---

### Answer by username_2 on 2017-03-30. Score: 1

This question would probably be better suited to engineering or electronic/electrical engineering.

My guess is that the breadboard will be used to test potential electronic circuits & being for ESA, possibly electronic circuits for satellites or probes.

Breadboards can be used to test different connection geometries of electronic components. These would need to be optimized for weight & energy consumption, particularly if they are to be launched into outer space. Software (algorithms) exist where this can be done using a virtual breadboard rather than a physical one

> **Comments:**
> **username_0**: Are you sure? The contexts I could find make no mention of electronics or electrical engineering, but seem to be about algorithm development only.  

---

