The formats are as follows. Please note that if a pulse terminates
during an FFT, the final entry may be truncated. So yes, you may not
always get an integer multiple of the relevant frame length.
Note that you shift each of the readings by max_exp to get a total
reading. max_index and max_magnitude I think are just derived from the
existing dataset; they're just a shortcut for software so it doesn't
have to parse the whole frame looking for the peak.
Static 20 mode:
0 bin -28 magnitude[7:0] = (|i| + |q|) >> max_exp
1 bin -27 magnitude[7:0] = (|i| + |q|) >> max_exp
2 - 53 …
54 bin 26 magnitude[7:0] = (|i| + |q|) >> max_exp
55 bin 27 magnitude[7:0] = (|i| + |q|) >> max_exp
56 [7:0]: all bins {max_magnitude[1:0], bitmap_weight[5:0]}
57 [7:0]: all bins max_magnitude[9:2]
58 [7:0]: all bins {max_index[5:0], max_magnitude[11:10]}
59 [3:0]: max_exp (shift amount to size max bin to 8-bit unsigned)
Dynamic 20/40 mode:
0 bin -64 magnitude[7:0] = (|i| + |q|) >> max_exp or power (in dBm)
1 bin -63 magnitude[7:0] = (|i| + |q|) >> max_exp or power (in dBm)
2 - 125 …
126 bin 62 magnitude[7:0] = (|i| + |q|) >> max_exp or power (in dBm)
127 bin 63 magnitude[7:0] = (|i| + |q|) >> max_exp or power (in dBm)
128 [7:0]: lower bins {max_magnitude[1:0], bitmap_weight[5:0]}
Baseband DFS 2 (Radar) Micro-Architecture
129 [7:0]: lower bins max_magnitude[9:2]
130 [7:0]: lower bins {max_index[5:0], max_magnitude[11:10]}
131 [7:0]: upper bins {max_magnitude[1:0], bitmap_weight[5:0]}
132 [7:0]: upper bins max_magnitude[9:2]
133 [7:0]: upper bins {max_index[5:0], max_magnitude[11:10]}
134 [3:0]: max_exp (shift amount to size max bin to 8-bit unsigned)
Ok, now for radar it's a tad different. There's a bit that is set if
the signal is above a certain threshold. If so, the bit is set to 1.
There's also a 3 bit magnitude value which is calculated against the
maximum magnitude value (floor(m(i) * 8 / max magnitude.)
This is optimised for digestion by radar code looking to identify
whether a longer pulse is a radar chirp (moving in frequency over
time) or not.
Static 20:
0 [3:0]: bin -28 {bitmap, quantized magnitude[2:0]}
[7:4]: bin -27 {bitmap, quantized magnitude[2:0]}
1 [3:0]: bin -26 {bitmap, quantized magnitude[2:0]}
[7:4]: bin -25 {bitmap, quantized magnitude[2:0]}
2 - 25 …
26 [3:0]: bin 24 {bitmap, quantized magnitude[2:0]}
[7:4]: bin 25 {bitmap, quantized magnitude[2:0]}
27 [3:0]: bin 26 {bitmap, quantized magnitude[2:0]}
[7:4]: bin 27 {bitmap, quantized magnitude[2:0]}
28 [7:0]: all bins {max_magnitude[1:0], bitmap_weight[5:0]}
29 [7:0]: all bins max_magnitude[9:2]
30 [7:0]: all bins {max_index[5:0], max_magnitude[11:10]}
Dynamic 20/40:
0 [3:0]: bin -64 {bitmap, quantized magnitude[2:0]}
[7:4]: bin -63 {bitmap, quantized magnitude[2:0]}
1 [3:0]: bin -62 {bitmap, quantized magnitude[2:0]}
[7:4]: bin -61 {bitmap, quantized magnitude[2:0]}
2 - 61 …
62 [3:0]: bin 60 {bitmap, quantized magnitude[2:0]}
[7:4]: bin 61 {bitmap, quantized magnitude[2:0]}
63 [3:0]: bin 62 {bitmap, quantized magnitude[2:0]}
[7:4]: bin 63 {bitmap, quantized magnitude[2:0]}
64 [7:0]: lower bins {max_magnitude[1:0], bitmap_weight[5:0]}
65 [7:0]: lower bins max_magnitude[9:2]
66 [7:0]: lower bins {max_index[5:0], max_magnitude[11:10]}
67 [7:0]: upper bins {max_magnitude[1:0], bitmap_weight[5:0]}
68 [7:0]: upper bins max_magnitude[9:2]
69 [7:0]: upper bins {max_index[5:0], max_magnitude[11:10]}
There you are. Please, go forth, write some open source code that
grabs this data and plots it in meaningful ways.
Adrian
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