The amplitude value of the IQ data for nrf5340dk is too low

Question

-21	45
17	-47
-16	45
9	-49
-8	46
11	-47
0	48
-19	-47
25	-54
-45	-25
-30	38
31	37
-8	-59
-52	7
-1	50
45	8
-53	-28
-34	40
35	37
43	-25
-59	-1
1	49
48	4
13	-47
-37	49
39	32
41	-26
-22	-40
-2	59
50	5
9	-52
-45	-15
41	41
41	-30
-22	-45
-46	18
59	5
8	-51
-49	-19
-21	44
49	-35
-29	-42
-41	26
17	46
8	-58
 
 hardware:nrf5340dk 
 The above 45 pairs of IQ data are a set of data that I have received.The maximum amplitude of the IQ data I received seems to be only 128, which means that the quantization of IQ data is only 7 bits, which may result in insufficient accuracy. I would like to know if it is possible to modify the configuration to increase the quantization bit count and thus increase the amplitude value of IQ data? I think the data obtained this way will have higher accuracy. 
 Thank you in advance for your help!

Simonr · Accepted Answer

Hi 
 IQ samples are set with the SAMPLEYPE field in the DFECTRL1 register and is described below (from the nRF52833 and nRF5340 product specification: 
 
 I would recommend that if you require better accuracy would be to use more antennas in your antenna array. Please see the Direction Finding whitepaper for more information. Also, please note that this is raw IQ data, so it must be converted into vector form to be reviewed properly. We don't have have any specific sample code showing this, but you can check out this page for information on the various formulas used to translate IQ data between polar and rectangular form. 
 Best regards, 
 Simon

The amplitude value of the IQ data for nrf5340dk is too low

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