[evlatests] More 3-bit stats ...

[Bryan Butler]

rick has pointed out that what i'm really interested in is the 
difference between A1C1 and A2C2.  he already showed the difference 
between A1C1 and B0D0.  sorry for my confusion!

	-bryan


Bryan Butler wrote, On 12/7/11 11:12 AM:
>
> did you do a ratio of A1C1 to B0D0?  my recollection is that one was
> quite a bit better for the 3-bit than the other, and we didn't
> understand why...
>
> 	-bryan
>
>
> Rick Perley wrote, On 12/7/11 9:54 AM:
>>       My report yesterday on the 3-bit noise yesterday for the various bit
>> levels was incomplete, as I had not compared the 3-bit noise levels to
>> the 8-bit 'truth'.  This is now done, but there are no surprises.  A
>> couple of perhaps interesting trends, however ...
>>
>>       To simplify the effort, I compared the histogram noises for the 012
>> and 345 bit selections to the 8-bit noises, taken at the same time, and
>> in the same frequency subband.  These two observations were taken at
>> different elevations (10 degrees different) and at different times (80
>> minutes).  There are four ratios of interest:
>>
>>       1) A1C1/B0D0 at the low elevation
>>       2) A1C1/B0D0 at the higher elevation
>>       3) A1C1(high)/A1C1(low)
>>       4) B0D0(high)/B0D0(low)
>>
>>       Results:
>>
>>       1) This shows the usual degradation of the 3-bit system, compared to
>> the 8-bit.  The ratios are a little higher than expected -- ranging from
>> 1.09 to 1.28.  However, the higher ratios are all associated with
>> specific antenna-polarizations:  26A1 is easily the worst (average
>> 1.25), and 23C1 a close second (1.17 average).  06C1 is also poor (1.14
>> average).
>>       2) This is the 3bit/8bit degradation ratio at the higher elevation.
>> Curiously, the values average a little less than those in (1) at the
>> lower elevation, ranging from 1.03 to 1.30.  The same antenna-IF
>> dependency noted in (1) is seen here also, but (for example), ea26A1 is
>> now 1.15, rather than 1.25, while ea06C1 is 1.20, rather than 1.14.  'It
>> goes both ways'.
>>       3) This is the ratio reported yesterday:  The average ratio is 0.98,
>> with a dispersion of .05.  The high end of the distribution is dominated
>> by ea06C1, with an average of 1.07.  (This is reflected in the ratios
>> given above in (1) and (2)).
>>       4) This average is  1.01, with a dispersion of .04.  The difference
>> in the averages in (4) and (3) reflect the difference between those in
>> (1) and (2).
>>
>>       My bottom line:  There's no salvation here.  The noise is the same
>> for any of these 3-bit selections, to within the measurement errors.
>>
>>
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