2.5.0
spase://NASA/NumericalData/MMS/2/FIELDS/DSP/Fast/Level2/ElectricFieldPowerSpectralDensity/PT2S
MMS 2 Digital Signal Processor (DSP) Double Probe (ADP, SDP), Electric Field Power Spectral Density, Level 2 (L2), Fast Mode, 2 s Data
MMS2_DSP_FAST_L2_EPSD
https://doi.org/10.48322/41kp-mn45
2023-03-04T12:34:56.789
2021-04-27T15:38:11
Only known prior ReleaseDate of the metadata
2022-08-04T12:34:56.789
Added DOI and PublicationInfo minted by LFB, updated the RepositoryID, updated the SPDF MetadataContact Person to Robert M. Candey, metadata updated to SPASE 2.4.1, reviewed by LFB 20220803
2023-03-04T12:34:56.789
Standardized the ResourceName Format, Set AlternateName equal to the ProductKey, Revised the Acknowledgement, PublicationInfo Authors, and Contact Person list per request of the MMS DSP/EDP team, metadata updated to SPASE 2.5.0, reviewed by LFB 20230304
The MMS electric field power spectral density (EPSD) is computed onboard by the Digital Signal Processor (DSP). The fast Fourier transform (FFT) calculation is performed on a digitized version of analog signals from the Axial Double Probe (ADP) and Spin-Plane Double Probe (SDP). This data product is computed in space from individual components that are not synchronized to the 1 second pulse. Therefore, the timing between channels can be inaccurate by a fraction of a second. The samples times are interval start times taken from the x component. The spectra are calculated via a 1024-point FFT algorithm on piecewise continuous sets of waveform data. Nine signals can be processed simultaneously. Six of the twelve DC-coupled E, DC-coupled V, or SCM signals (16384 samples/s) are selected for spectral processing at 100% duty cycle. In addition, the three AC-coupled signals (262,144 kS/s) each can be processed at 6.25% duty cycle. Each of the nine signals has 16, 1024-point FFT operations every second; the field-programmable gate array (FPGA) performs 144 FFTs per second. The FFT is performed by an arithmetic logic unit (ALU), which is controlled by a state machine. Both are hard-coded into the FPGA. The operation starts by applying a 1024-point Hanning window onto a waveform. Next, an FFT is implemented. The FFT is broken into a series of "butterfly" operations performed by the ALU. The result has real and imaginary data. Power spectra are calculated by taking the sum of squares of real and imaginary values (the ALU includes a multiplier), which produces a power spectrum with 512 frequency bins. The frequency bins are then combined to give pseudo-logarithmic frequency spacing (del f)/f. The spectra are reduced to 56 frequency bins with (del f)/f between 6% and 12% when possible. Narrow-band emissions can be fit to an accuracy of (del f)/f ~3%, allowing for an accurate determination of plasma density. The spectra can be averaged in time. The fastest reporting rate of any signal is 16 spectra per second. Reporting rates can be as slow a one spectra every 16 s (averaging 256 spectra). The averaging process has 48-bit accuracy to maximize the dynamic range. The amplitudes undergo a pseudo-logarithmic compression to an 8-bit number representing over 120 dB of dynamic range at ~5% precision.
Please acknowledge R.E. Ergun, P.-A. Lindqvist, R.B. Torbert, N. Ahmadi, D.B. Graham, and J.L. Burch for use of these data
Ergun, Robert, E.; Lindqvist, Per-Arne; Torbert, Roy, B.; Ahmadi, Narges; Graham, Daniel, Bruce; Burch, James, L.
2022-01-01T00:00:00
NASA Space Physics Data Facility
spase://SMWG/Person/Robert.E.Ergun
InstrumentLead
CoInvestigator
spase://SMWG/Person/Per-Arne.Lindqvist
InstrumentLead
CoInvestigator
spase://SMWG/Person/Roy.B.Torbert
InstrumentLead
CoInvestigator
spase://SMWG/Person/Narges.Ahmadi
CoInvestigator
spase://SMWG/Person/Daniel.Bruce.Graham
CoInvestigator
spase://SMWG/Person/James.L.Burch
PrincipalInvestigator
spase://SMWG/Person/MMS_SDC_POC
HostContact
spase://SMWG/Person/Robert.M.Candey
MetadataContact
spase://SMWG/Person/Lee.Frost.Bargatze
MetadataContact
The Magnetospheric Multiscale (MMS) Mission home page at Goddard Space Flight Center (GSFC)
https://mms.gsfc.nasa.gov/
The Magnetospheric Multiscale (MMS) Mission Home Page hosted by the Goddard Space Flight Center (GSFC).
spase://VSPO/NumericalData/MMS/2/FIELDS/DSP/Fast/Level2/ElectricFieldPowerSpectralDensity/PT2S
spase://SMWG/Repository/UCOLO/LASP/MMS_SDC
Online
Open
FTPS from the MMS SDC (not with most browsers)
ftps://lasp.colorado.edu/mms/sdc/public/data/mms2/dsp/fast/l2/epsd/
In CDF via ftp from the MMS Science Data Center
HTTPS from the MMS SDC
https://lasp.colorado.edu/mms/sdc/public/data/mms2/dsp/fast/l2/epsd/
In CDF via http from the MMS Science Data Center
CDF
None
Please acknowledge R.E. Ergun, P.-A. Lindqvist, R.B. Torbert, N. Ahmadi, D.B. Graham, and J.L. Burch. Also please acknowledge the data providers and CDAWeb when using these data.
spase://SMWG/Repository/NASA/GSFC/SPDF/CDAWeb
Online
Open
FTPS from SPDF (not with most browsers)
ftps://spdf.gsfc.nasa.gov/pub/data/mms/mms2/dsp/fast/l2/epsd/
In CDF via ftp from SPDF
HTTPS from SPDF
https://spdf.gsfc.nasa.gov/pub/data/mms/mms2/dsp/fast/l2/epsd/
In CDF via http from SPDF
CDAWeb
https://cdaweb.gsfc.nasa.gov/cgi-bin/eval2.cgi?dataset=MMS2_DSP_FAST_L2_EPSD&index=sp_phys
MMS2_DSP_FAST_L2_EPSD
Access to ASCII, CDF, and plots via NASA/GSFC CDAWeb
CDF
None
Please acknowledge R.E. Ergun, P.-A. Lindqvist, R.B. Torbert, N. Ahmadi, D.B. Graham, and J.L. Burch. Also please acknowledge the data providers and CDAWeb when using these data.
spase://SMWG/Repository/NASA/GSFC/SPDF/CDAWeb
Online
Open
CDAWeb HAPI Server
https://cdaweb.gsfc.nasa.gov/hapi
MMS2_DSP_FAST_L2_EPSD
Web Service to this product using the HAPI interface
CSV
Please acknowledge R.E. Ergun, P.-A. Lindqvist, R.B. Torbert, N. Ahmadi, D.B. Graham, and J.L. Burch. Also please acknowledge the data providers and CDAWeb when using these data.
Calibrated
spase://SMWG/Instrument/MMS/2/FIELDS/ADP
spase://SMWG/Instrument/MMS/2/FIELDS/DSP
spase://SMWG/Instrument/MMS/2/FIELDS/SDP
ElectricField
Waves.Passive
2015-03-17T00:00:00.000
-P2M
PT2S
Earth.Magnetosheath
Earth.Magnetosphere
Earth.Magnetosphere.Magnetotail
Earth.Magnetosphere.Main
Earth.Magnetosphere.RadiationBelt
Earth.NearSurface.EquatorialRegion
Earth.NearSurface.Plasmasphere
Heliosphere.NearEarth
Epoch
Epoch
Epoch
This parameter exhibits an increasing monotonic progression.
PT2S
ns
1.0e-9>s
Epoch
LinearScale
2000-01-01T00:00:00.000000000
2030-01-01T00:00:00.999000000
9999-12-31T23:59:59.999999999
Temporal
Epoch_timetag
Epoch_timetag
Epoch Time Tag
This parameter exhibits an increasing monotonic progression.
PT2S
ns
1.0e-9>s
Epoch_timetag
e14.8
LinearScale
1970-01-01T00:00:00.000000000
2030-01-01T00:00:00.999999999
9999-12-31T23:59:59.999999999
Temporal
mms2_dsp_epsd_x
Time series defined by using: EPOCH
mms2_dsp_epsd_x
EPSD, X-Component
Average Type: standard
PT2S
(V/m)^2/Hz
Cartesian
SC
Spectrogram
e13.6
LogScale
88
1
1
8.0
2
2
24.0
3
3
40.0
4
4
56.0
5
5
72.0
6
6
88.0
7
7
104.0
8
8
120.0
9
9
136.0
10
10
152.0
11
11
168.0
12
12
184.0
13
13
200.0
14
14
216.0
15
15
232.0
16
16
248.0
17
17
272.0
18
18
304.0
19
19
336.0
20
20
368.0
21
21
400.0
22
22
432.0
23
23
464.0
24
24
496.0
25
25
544.0
26
26
608.0
27
27
672.0
28
28
736.0
29
29
800.0
30
30
864.0
31
31
928.0
32
32
992.0
33
33
1088.0
34
34
1216.0
35
35
1344.0
36
36
1472.0
37
37
1600.0
38
38
1728.0
39
39
1856.0
40
40
1984.0
41
41
2176.0
42
42
2432.0
43
43
2688.0
44
44
2944.0
45
45
3200.0
46
46
3456.0
47
47
3712.0
48
48
3968.0
49
49
4352.0
50
50
4864.0
51
51
5376.0
52
52
5888.0
53
53
6400.0
54
54
6912.0
55
55
7424.0
56
56
7936.0
57
57
8704.0
58
58
9728.0
59
59
10752.0
60
60
11776.0
61
61
12800.0
62
62
13824.0
63
63
14848.0
64
64
15872.0
65
65
17408.0
66
66
19456.0
67
67
21504.0
68
68
23552.0
69
69
25600.0
70
70
27648.0
71
71
29696.0
72
72
31744.0
73
73
34816.0
74
74
38912.0
75
75
43008.0
76
76
47104.0
77
77
51200.0
78
78
55296.0
79
79
59392.0
80
80
63488.0
81
81
69632.0
82
82
77824.0
83
83
86016.0
84
84
94208.0
85
85
102400.0
86
86
110592.0
87
87
118784.0
88
88
126976.0
0.0
2.0e-05
-1.0e+31
PlasmaWaves
Component.I
Intensity
mms2_dsp_epsd_y
Time series defined by using: EPOCH
mms2_dsp_epsd_y
EPSD, Y-Component
Average Type: standard
PT2S
(V/m)^2/Hz
Cartesian
SC
Spectrogram
e13.6
LogScale
88
1
1
8.0
2
2
24.0
3
3
40.0
4
4
56.0
5
5
72.0
6
6
88.0
7
7
104.0
8
8
120.0
9
9
136.0
10
10
152.0
11
11
168.0
12
12
184.0
13
13
200.0
14
14
216.0
15
15
232.0
16
16
248.0
17
17
272.0
18
18
304.0
19
19
336.0
20
20
368.0
21
21
400.0
22
22
432.0
23
23
464.0
24
24
496.0
25
25
544.0
26
26
608.0
27
27
672.0
28
28
736.0
29
29
800.0
30
30
864.0
31
31
928.0
32
32
992.0
33
33
1088.0
34
34
1216.0
35
35
1344.0
36
36
1472.0
37
37
1600.0
38
38
1728.0
39
39
1856.0
40
40
1984.0
41
41
2176.0
42
42
2432.0
43
43
2688.0
44
44
2944.0
45
45
3200.0
46
46
3456.0
47
47
3712.0
48
48
3968.0
49
49
4352.0
50
50
4864.0
51
51
5376.0
52
52
5888.0
53
53
6400.0
54
54
6912.0
55
55
7424.0
56
56
7936.0
57
57
8704.0
58
58
9728.0
59
59
10752.0
60
60
11776.0
61
61
12800.0
62
62
13824.0
63
63
14848.0
64
64
15872.0
65
65
17408.0
66
66
19456.0
67
67
21504.0
68
68
23552.0
69
69
25600.0
70
70
27648.0
71
71
29696.0
72
72
31744.0
73
73
34816.0
74
74
38912.0
75
75
43008.0
76
76
47104.0
77
77
51200.0
78
78
55296.0
79
79
59392.0
80
80
63488.0
81
81
69632.0
82
82
77824.0
83
83
86016.0
84
84
94208.0
85
85
102400.0
86
86
110592.0
87
87
118784.0
88
88
126976.0
0.0
2.0e-05
-1.0e+31
PlasmaWaves
Component.J
Intensity
mms2_dsp_epsd_z
Time series defined by using: EPOCH
mms2_dsp_epsd_z
EPSD, Z-Component
Average Type: standard
PT2S
(V/m)^2/Hz
Cartesian
SC
Spectrogram
e13.6
LogScale
88
1
1
8.0
2
2
24.0
3
3
40.0
4
4
56.0
5
5
72.0
6
6
88.0
7
7
104.0
8
8
120.0
9
9
136.0
10
10
152.0
11
11
168.0
12
12
184.0
13
13
200.0
14
14
216.0
15
15
232.0
16
16
248.0
17
17
272.0
18
18
304.0
19
19
336.0
20
20
368.0
21
21
400.0
22
22
432.0
23
23
464.0
24
24
496.0
25
25
544.0
26
26
608.0
27
27
672.0
28
28
736.0
29
29
800.0
30
30
864.0
31
31
928.0
32
32
992.0
33
33
1088.0
34
34
1216.0
35
35
1344.0
36
36
1472.0
37
37
1600.0
38
38
1728.0
39
39
1856.0
40
40
1984.0
41
41
2176.0
42
42
2432.0
43
43
2688.0
44
44
2944.0
45
45
3200.0
46
46
3456.0
47
47
3712.0
48
48
3968.0
49
49
4352.0
50
50
4864.0
51
51
5376.0
52
52
5888.0
53
53
6400.0
54
54
6912.0
55
55
7424.0
56
56
7936.0
57
57
8704.0
58
58
9728.0
59
59
10752.0
60
60
11776.0
61
61
12800.0
62
62
13824.0
63
63
14848.0
64
64
15872.0
65
65
17408.0
66
66
19456.0
67
67
21504.0
68
68
23552.0
69
69
25600.0
70
70
27648.0
71
71
29696.0
72
72
31744.0
73
73
34816.0
74
74
38912.0
75
75
43008.0
76
76
47104.0
77
77
51200.0
78
78
55296.0
79
79
59392.0
80
80
63488.0
81
81
69632.0
82
82
77824.0
83
83
86016.0
84
84
94208.0
85
85
102400.0
86
86
110592.0
87
87
118784.0
88
88
126976.0
0.0
2.0e-05
-1.0e+31
PlasmaWaves
Component.K
Intensity
mms2_dsp_epsd_omni
Time series defined by using: EPOCH
mms2_dsp_epsd_omni
EPSD, Omni-directional
Average Type: standard
PT2S
(V/m)^2/Hz
Spectrogram
e13.6
LogScale
88
1
1
8.0
2
2
24.0
3
3
40.0
4
4
56.0
5
5
72.0
6
6
88.0
7
7
104.0
8
8
120.0
9
9
136.0
10
10
152.0
11
11
168.0
12
12
184.0
13
13
200.0
14
14
216.0
15
15
232.0
16
16
248.0
17
17
272.0
18
18
304.0
19
19
336.0
20
20
368.0
21
21
400.0
22
22
432.0
23
23
464.0
24
24
496.0
25
25
544.0
26
26
608.0
27
27
672.0
28
28
736.0
29
29
800.0
30
30
864.0
31
31
928.0
32
32
992.0
33
33
1088.0
34
34
1216.0
35
35
1344.0
36
36
1472.0
37
37
1600.0
38
38
1728.0
39
39
1856.0
40
40
1984.0
41
41
2176.0
42
42
2432.0
43
43
2688.0
44
44
2944.0
45
45
3200.0
46
46
3456.0
47
47
3712.0
48
48
3968.0
49
49
4352.0
50
50
4864.0
51
51
5376.0
52
52
5888.0
53
53
6400.0
54
54
6912.0
55
55
7424.0
56
56
7936.0
57
57
8704.0
58
58
9728.0
59
59
10752.0
60
60
11776.0
61
61
12800.0
62
62
13824.0
63
63
14848.0
64
64
15872.0
65
65
17408.0
66
66
19456.0
67
67
21504.0
68
68
23552.0
69
69
25600.0
70
70
27648.0
71
71
29696.0
72
72
31744.0
73
73
34816.0
74
74
38912.0
75
75
43008.0
76
76
47104.0
77
77
51200.0
78
78
55296.0
79
79
59392.0
80
80
63488.0
81
81
69632.0
82
82
77824.0
83
83
86016.0
84
84
94208.0
85
85
102400.0
86
86
110592.0
87
87
118784.0
88
88
126976.0
0.0
2.0e-05
-1.0e+31
PlasmaWaves
Total
Intensity
mms2_dsp_seqcnt_lfe
Time series defined by using: EPOCH_TIMETAG
mms2_dsp_seqcnt_lfe
Sequence Count
PT2S
TimeSeries
i6
LinearScale
0
65535
65535
Other
mms2_e_freq
mms2_e_freq
EPSD, Frequency Midpoints
PT2S
e10.6
88
1
1
2
2
3
3
4
4
5
5
6
6
7
7
8
8
9
9
10
10
11
11
12
12
13
13
14
14
15
15
16
16
17
17
18
18
19
19
20
20
21
21
22
22
23
23
24
24
25
25
26
26
27
27
28
28
29
29
30
30
31
31
32
32
33
33
34
34
35
35
36
36
37
37
38
38
39
39
40
40
41
41
42
42
43
43
44
44
45
45
46
46
47
47
48
48
49
49
50
50
51
51
52
52
53
53
54
54
55
55
56
56
57
57
58
58
59
59
60
60
61
61
62
62
63
63
64
64
65
65
66
66
67
67
68
68
69
69
70
70
71
71
72
72
73
73
74
74
75
75
76
76
77
77
78
78
79
79
80
80
81
81
82
82
83
83
84
84
85
85
86
86
87
87
88
88
8.0
126976.0
-1.0e+31
Other