SMA 12.4 GHz Phase Monitor

Documentation

Calibration of A/D gain

Time scales of structures in DSM

Array index PHASE_STRUCT_V10_V19_F RMS_PHASE_V10_V12_D
0 1 1
1 2 2
2 4 4
3 8 8
4 16 16
5 32 32
6 64 64
7 128 128
8 256 256
9 512 512
10 768 1024
11 1024 2048
12 1280 -
13 1536 -
14 1792 -
15 2048 -
16 2304 -
17 2560 -
18 2816 -

For the phase structure function data the intervals for a single baseline are calculated for Bob's structure function with the following:
for (t = 1, nsfp = 0; t < ANALYZE_LEN / 2 && nsfp < NUMSFP - 1;) {

              sf[nsfp].span = t;
              t = (t < 256) ? t * 2 : t + 256;
	      nsfp++;
}

Where ANALYZE_LEN = 6000 (10 minutes of data) and NUMSFP = 21;

so the intervals are 1, 2, 4, 8, 16, 32, 64, 128, 256, 512, 768, 1024, 1280, 1536, 1792, 2048, 2304, 2560, 2816

The call to Bob's structure function is:
strfn(phase_struct_points, NPOINTS, sf, nsfp, baseline);
phase_struct_points = array of 6000 atmospheric phase points
NPOINTS = 100
sf = pointer to structure function
nsfp = 19 from above for loop
baseline = baseline

Bob Wilson's description of strfn.c

'> /* strfn calculates the structure function of an array of phase points.
'> * Each call to strfn should pass npoints of new phase data in the array
'> * points. The new points will be put in the local buffer. If at least
'> * ANALYZE_LEN points have been acquired, strfn returns true, calculates the
'> * structure function and puts the results in the array of sfp structures.
'> * nsfp is the number of spans to be calculated. The spans to be calcualted
'> * must be passed to strfn in the sfp array. After the first call,
'> * structure function will be calculated incrementally unless nsfp is
'> * changed, so the array of nsf structures should not be changed between
'> * calls unless nsfp is also changed forcing a complete recalculation.
'> * If fewer than ANALYZE_LEN points have been acquired, strfn returns
'> * zero and does no calculation.
'> */

-- ToddHunter - 2011-02-13
Topic attachments
I Attachment Action Size Date Who Comment
26193.1321558836.txt.report.pdfpdf 26193.1321558836.txt.report.pdf manage 1 MB 2011-11-17 - 16:08 ToddHunter Oct 19-23, 2011 solutions
Estimating_the_noise_floor_of_an_API_given_the_signal_to_noise_of_the_received_satellite_signal.pdfpdf Estimating_the_noise_floor_of_an_API_given_the_signal_to_noise_of_the_received_satellite_signal.pdf manage 29 K 2012-03-12 - 16:31 ToddHunter Kim's sensitivity derivation
fitsix.py.txttxt fitsix.py.txt manage 22 K 2017-12-04 - 12:53 ToddHunter script to take up to 10 baselines of data (correlated amplitude, unwrapped phase, temperature) and determine I/Q gain factor model and the subsequent temperature dependence of the residual from the model
phaseErrorByBobWilson.pdfpdf phaseErrorByBobWilson.pdf manage 1 MB 2012-03-08 - 09:40 ToddHunter Bob Wilson's writeup on the expected sensitivity
plotJuly2010.py.txttxt plotJuly2010.py.txt manage 1 K 2012-03-09 - 18:17 ToddHunter script that creates Figure 5 of the API paper
solutionsEXT solutions manage 874 bytes 2011-02-14 - 00:08 ToddHunter fitted solutions from July 2010
strfn.cc strfn.c manage 3 K 2012-01-05 - 12:56 ToddHunter Bob's phase structure function subroutine
Topic revision: r8 - 2017-12-04, ToddHunter
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