Version:2.2.8
NumericalData
ResourceID
spase://NASA/NumericalData/ISIS1/SFS/AverageIonogram/Quito/Corrected/PT29S
ResourceHeader
ResourceName
ISIS-1 Topside Sounder Average Ionogram over Quito, Equador, Version 2: QUI, Latitude -1, Longitude 281
ReleaseDate
2020-07-07 21:14:41Z
Description
This Ionogram was digitized from the original ISIS 1 Analog Telemetry Data on 7-Track Tape using the Facilities of the Data Evaluation Laboratory at NASA GSFC, Code 500. This Data Restoration Project is headed by Dr. R.F. Benson, NASA GSFC, Code 692. Ionograms were digitized at the Rate of 40,000 16-bit samples/s. This Sample Rate is higher than the Nyquist Frequency of 30 kHz. The Sample Frequency of 40 kHz provides a Measurement every 25 ms corresponding to an Apparent Range Interval of c*t/2, where c is the Speed of Light, or 3.747 km. Each Ionogram consists of a Fixed Frequency Portion and a Swept Frequency Portion. The Time Resolution is typically 29 s.
Acknowledgement
James H. Whitteker, Robert F. Benson, Dieter K. Bilitza. Please thank James H. Whitteker, Principal Investigator for the ISIS 1 Swept Frequency Sounder, SFS, Instrument and Robert F. Benson, Project Scientist for the Alouette/ISIS Data-Restoration
Contacts
InformationURL
Name
ISIS/Alouette Topside Sounder Data Restoration Project Site
URL
Description
ISIS/Alouette Page maintained by NASA GSFC with Science and Instrument Descriptions, Data Access, Software, and Publication Lists
InformationURL
Name
NSSDC Master Catalog
URL
Description
Information about the Swept Frequency Sounder, SFS, Experiment on Alouette 2
PriorIDs
spase://VSPO/NumericalData/ISIS1/SFS/AverageIonogram/Quito/Corrected/PT29S
AccessInformation
RepositoryID
Availability
Online
AccessRights
Open
AccessURL
Name
FTPS from SPDF (not with most browsers)
URL
Description
Access to Data in CDF Format via ftp from SPDF
AccessURL
Name
HTTPS from SPDF
URL
Description
Access to Data in CDF Format via http from SPDF
Format
CDF
Encoding
None
Acknowledgement
James H. Whitteker, Robert F. Benson, Dieter K. Bilitza. Please thank James H. Whitteker, Principal Investigator for the ISIS 1 Swept Frequency Sounder, SFS, Instrument and Robert F. Benson, Project Scientist for the Alouette/ISIS Data-Restoration. Please acknowledge the data providers and CDAWeb when using these data.
ProcessingLevel
Calibrated
InstrumentIDs
MeasurementType
Spectrum
MeasurementType
Waves.Active
TemporalDescription
TimeSpan
StartDate
1976-01-26 22:51:04
StopDate
1976-07-16 10:49:12
Note
The Cadence is 31 s between Ionograms. The Alouette 2 Ionograms have the slowest Sweep Rate of any of the Alouette/ISIS Topside Sounders sweeping from 0.12 to 14.5 MHz in about 28 s with a Frequency Sweep Rate of 0.13 MHz/s below 2.0 MHz, providing the highest Frequency Resolution of any of the ISIS Program Sounders. The Alouette 2 Frequency Sweep Rate above 2 MHz was 1 MHz/s. Alouette 2 did not have a Fixed Frequency Operation.
Cadence
PT29S
SpectralRange
RadioFrequency
ObservedRegion
Earth.Magnetosphere
ObservedRegion
Earth.Magnetosphere.Polar
ObservedRegion
Earth.NearSurface
ObservedRegion
Earth.NearSurface.AuroralRegion
ObservedRegion
Earth.NearSurface.EquatorialRegion
ObservedRegion
Earth.NearSurface.Ionosphere
ObservedRegion
Earth.NearSurface.PolarCap
Keywords
Ionogram
Topside Sounder
Swept Frequency Sounder
Topside Ionosphere
Ionospheric Reflections
Ground Reflections
Ionospheric Echoes
Ground Echoes
Ducted Echoes
Wave Scattering
Field-Aligned Irregularities, FAI
Plasma Resonance
Plasma Waves
Auroral Kilometric Radiation, AKR
Solar Type III Bursts
Upper Hybrid Noise Band
Parameter #1
Name
Satellite ID
ParameterKey
satellite
Description
Satellite ID: 1=Alouette 1, 2=Alouette 2, 3=ISIS 1, 4=ISIS 2
Cadence
PT29S
RenderingHints
AxisLabel
s/c_ID
ValueFormat
I1
ScaleMin
1
ScaleMax
4
ValidMin
1
ValidMax
4
FillValue
-2147483648
Support
Parameter #2
Name
Telemetry Station Code
ParameterKey
station_id
Description
Two-Digit Telemetry Station Code
Cadence
PT29S
RenderingHints
AxisLabel
station
ValueFormat
I2
ScaleMin
1
ScaleMax
99
ValidMin
1
ValidMax
99
FillValue
-2147483648
Support
Parameter #3
Name
Transmitter Power Code
ParameterKey
power_code
Description
Transmitter Power Code: 1=Primary, 400 W, 2=Secondary, 400 W
Cadence
PT29S
RenderingHints
AxisLabel
T_power
ValueFormat
I1
ScaleMin
1
ScaleMax
2
ValidMin
1
ValidMax
2
FillValue
-2147483648
Support
SupportQuantity
InstrumentMode
Parameter #4
Name
Sounder-Receiver Code
ParameterKey
s/r_code
Description
Sounder-Receiver Code: 0=Off, 1=On
Cadence
PT29S
RenderingHints
AxisLabel
s/r_code
ValueFormat
I1
ScaleMin
0
ScaleMax
1
ValidMin
0
ValidMax
1
FillValue
-2147483648
Support
SupportQuantity
InstrumentMode
Parameter #5
Name
Pulse per Second Code
ParameterKey
pps_code
Description
Pulse per Second Code: 0=30 Pulses/s, 1=60 Pulses/s
Cadence
PT29S
RenderingHints
AxisLabel
pps_code
ValueFormat
I1
ScaleMin
0
ScaleMax
1
ValidMin
0
ValidMax
1
FillValue
-2147483648
Support
SupportQuantity
InstrumentMode
Parameter #6
Name
DMODE Code
ParameterKey
DMODE
Description
DMODE, Transmission On/Off for Alternate Frame Pairs: 0=Off, 1=On
Cadence
PT29S
RenderingHints
AxisLabel
DMODE
ValueFormat
I1
ScaleMin
0
ScaleMax
1
ValidMin
0
ValidMax
1
FillValue
-2147483648
Support
SupportQuantity
InstrumentMode
Parameter #7
Name
GMODE Code
ParameterKey
GMODE
Description
GMODE, Transmission of Alternate Frames of Fixed Frequency Ionograms and Normal Combined Fixed Frequency and Swept Frequency Ionograms: 0=Off, 1=On
Cadence
PT29S
RenderingHints
AxisLabel
GMODE
ValueFormat
I1
ScaleMin
0
ScaleMax
1
ValidMin
0
ValidMax
1
FillValue
-2147483648
Support
SupportQuantity
InstrumentMode
Parameter #8
Name
Sounder Mixed Mode
ParameterKey
mixed_mode
Description
Sounder Mixed Mode, Transmission at a Fixed Frequency while the Sounder-Receiver sweeps over the Swept Frequency Range: 0=Off, 1=On
Cadence
PT29S
RenderingHints
AxisLabel
s_m_mode
ValueFormat
I1
ScaleMin
0
ScaleMax
1
ValidMin
0
ValidMax
1
FillValue
-2147483648
Support
SupportQuantity
InstrumentMode
Parameter #9
Name
Fixed Frequency Code
ParameterKey
fix_freq
Description
Fixed Frequency Code: 0=Off, 1=0.25 MHz, 2=0.48 MHz, 3=1.00 MHz, 4=1.95 MHz, 5=4.00 MHz, 6=9.303 MHz
Cadence
PT29S
RenderingHints
AxisLabel
f_code
ValueFormat
I1
ScaleMin
0
ScaleMax
6
ValidMin
0
ValidMax
6
FillValue
-2147483648
Support
SupportQuantity
InstrumentMode
Parameter #10
Name
Year
ParameterKey
year
Description
Year of Ionogram Frame Sync
Cadence
PT29S
RenderingHints
AxisLabel
year
ValueFormat
I2
ScaleMin
62
ScaleMax
83
ValidMin
62
ValidMax
84
FillValue
-2147483648
Support
Parameter #11
Name
Day of Year
ParameterKey
doy
Description
Day of Year of Ionogram Frame Sync
Cadence
PT29S
RenderingHints
AxisLabel
DOY
ValueFormat
I3
ScaleMin
1
ScaleMax
366
ValidMin
1
ValidMax
366
FillValue
-2147483648
Support
Parameter #12
Name
Hour of Day
ParameterKey
hr
Description
Hour of Day of Ionogram Frame Sync, UT
Cadence
PT29S
RenderingHints
AxisLabel
Hour
ValueFormat
I2
ScaleMin
0
ScaleMax
24
ValidMin
0
ValidMax
24
FillValue
-2147483648
Support
Parameter #13
Name
Minute of Hour
ParameterKey
min
Description
Minute of Hour of Ionogram Frame Sync, UT
Cadence
PT29S
RenderingHints
AxisLabel
min
ValueFormat
I2
ScaleMin
0
ScaleMax
60
ValidMin
0
ValidMax
60
FillValue
-2147483648
Support
Parameter #14
Name
Second of Minute
ParameterKey
sec
Description
Second of Minute of Ionogram Frame Sync, UT
Cadence
PT29S
RenderingHints
AxisLabel
second
ValueFormat
F7.4
ScaleMin
0.0
ScaleMax
60.0
ValidMin
0.0
ValidMax
60.0
FillValue
-1.0e+31
Support
Parameter #15
Name
Local Mean Time
ParameterKey
LMT
Description
Local Mean Time, LMT, at the Time of Ionogram Frame Sync, Format: HH,MM
Cadence
PT29S
RenderingHints
Structure
Size
2
Element
Name
Element 1
Index
1
Units
h
UnitsConversion
60>s
ValidMin
0
ValidMax
24
RenderingHints
AxisLabel
LMT(hh)
ScaleMin
0
ScaleMax
24
Element
Name
Element 2
Index
2
Units
min
UnitsConversion
3600>s
ValidMin
0
ValidMax
60
RenderingHints
AxisLabel
LMT(mm)
ScaleMin
0
ScaleMax
60
FillValue
-2147483648
Support
Qualifier
DirectionAngle.AzimuthAngle
SupportQuantity
Positional
Parameter #16
Name
Geographic Coordinates
ParameterKey
geo_coord
Description
Geographic Coordinates, GEO, Latitude, Longitude, Height, at the Time of Ionogram Frame Sync
Cadence
PT29S
CoordinateSystem
CoordinateRepresentation
Spherical
CoordinateSystemName
GEO
RenderingHints
Structure
Size
3
Element
Name
Element 1
Index
1
Units
°
UnitsConversion
0.0174532925>rad
ValidMin
-90.0
ValidMax
90.0
RenderingHints
AxisLabel
latitude
ScaleMin
-90.0
ScaleMax
90.0
Element
Name
Element 2
Index
2
Units
°
UnitsConversion
0.0174532925>rad
ValidMin
0.0
ValidMax
360.0
RenderingHints
AxisLabel
longitude
ScaleMin
0.0
ScaleMax
360.0
Element
Name
Element 3
Index
3
Units
km
UnitsConversion
1e3>m
ValidMin
0.0
ValidMax
10000.0
RenderingHints
AxisLabel
height
ScaleMin
0.0
ScaleMax
10000.0
FillValue
-1.0e+31
Support
Qualifier
Vector
SupportQuantity
Positional
Parameter #17
Name
Geomagnetic Local Time
ParameterKey
GMLMT
Description
Geomagnetic Local Time, GMLMT, Format: HH,MM, at the Time of Ionogram Frame Sync
Cadence
PT29S
CoordinateSystem
CoordinateRepresentation
Spherical
CoordinateSystemName
LGM
RenderingHints
Structure
Size
2
Element
Name
Element 1
Index
1
Units
h
UnitsConversion
60>s
ValidMin
0
ValidMax
24
RenderingHints
AxisLabel
GMLMT(hh)
ScaleMin
0
ScaleMax
24
Element
Name
Element 2
Index
2
Units
min
UnitsConversion
3600>s
ValidMin
0
ValidMax
60
RenderingHints
AxisLabel
GMLMT(mm)
ScaleMin
0
ScaleMax
60
FillValue
-2147483648
Support
Qualifier
DirectionAngle.AzimuthAngle
SupportQuantity
Positional
Parameter #18
Name
Geomagnetic Latitude
ParameterKey
GMLAT
Description
Geomagnetic Latitude, MAG, at the Time of Ionogram Frame Sync
Cadence
PT29S
Units
°
UnitsConversion
0.0174532925>rad
CoordinateSystem
CoordinateRepresentation
Spherical
CoordinateSystemName
MAG
RenderingHints
AxisLabel
geom_lat
ValueFormat
F7.2
ScaleMin
-90.0
ScaleMax
90.0
ValidMin
-90.0
ValidMax
90.0
FillValue
-1.0e+31
Support
Qualifier
DirectionAngle.ElevationAngle
SupportQuantity
Positional
Parameter #19
Name
Geomagnetic Longitude
ParameterKey
GMLONG
Description
Geomagnetic Longitude, MAG, at the Time of Ionogram Frame Sync
Cadence
PT29S
Units
°
UnitsConversion
0.0174532925>rad
CoordinateSystem
CoordinateRepresentation
Spherical
CoordinateSystemName
MAG
RenderingHints
AxisLabel
geom_long
ValueFormat
F7.2
ScaleMin
-180.0
ScaleMax
180.0
ValidMin
-180.0
ValidMax
360.0
FillValue
-1.0e+31
Support
Qualifier
DirectionAngle.AzimuthAngle
SupportQuantity
Positional
Parameter #20
Name
Invariant Latitude
ParameterKey
INV_LAT
Description
Invariant Latitude, at the Time of Ionogram Frame Sync
Cadence
PT29S
Units
°
UnitsConversion
0.0174532925>rad
RenderingHints
AxisLabel
inv_lat
ValueFormat
F7.2
ScaleMin
-90.0
ScaleMax
90.0
ValidMin
-90.0
ValidMax
90.0
FillValue
-1.0e+31
Support
Qualifier
DirectionAngle.ElevationAngle
SupportQuantity
Positional
Parameter #21
Name
Magnetic Inclination
ParameterKey
DIP
Description
Magnetic Inclination, Dip Angle of Magnetic Field Direction, at the Time of Ionogram Frame Sync
Cadence
PT29S
Units
°
UnitsConversion
0.0174532925>rad
CoordinateSystem
CoordinateRepresentation
Spherical
CoordinateSystemName
LGM
RenderingHints
AxisLabel
DIP
ValueFormat
I3
ScaleMin
-90
ScaleMax
90
ValidMin
-90
ValidMax
90
FillValue
-2147483648
Field
Qualifier
DirectionAngle.ElevationAngle
FieldQuantity
Magnetic
Parameter #22
Name
Solar Zenith Angle
ParameterKey
CHI
Description
Solar Zenith Angle, SZA, at the Time of Ionogram Frame Sync
Cadence
PT29S
Units
°
UnitsConversion
0.0174532925>rad
RenderingHints
AxisLabel
CHI
ValueFormat
F7.2
ScaleMin
0
ScaleMax
180
ValidMin
0
ValidMax
180
FillValue
-2147483648
Support
Qualifier
DirectionAngle.PolarAngle
SupportQuantity
Positional
Parameter #23
Name
L Shell
ParameterKey
L
Description
L Shell, McIlwain Parameter, at the Time of Ionogram Frame Sync
Cadence
PT29S
RenderingHints
AxisLabel
L
ValueFormat
F7.2
ScaleMin
0.0
ScaleMax
180.0
ValidMin
0.0
ValidMax
180.0
FillValue
-1.0e+31
Support
Parameter #24
Name
Spacecraft Sunlight
ParameterKey
sun
Description
Spacecraft Sunlight: 0=Out, 1=In, at the Time of Ionogram Frame Sync
Cadence
PT29S
RenderingHints
AxisLabel
sun
ValueFormat
I1
ScaleMin
1
ScaleMax
2
ValidMin
1
ValidMax
2
FillValue
-2147483648
Support
Parameter #25
Name
CEP, Instrument Status
ParameterKey
CEP
Description
Cylindrical Electrostatic Probe, CEP, Instrument Status: 0=Off, 1=On
Cadence
PT29S
RenderingHints
AxisLabel
CEP
ValueFormat
I1
ScaleMin
0
ScaleMax
1
ValidMin
0
ValidMax
1
FillValue
-2147483648
Support
SupportQuantity
InstrumentMode
Parameter #26
Name
VLF, Instrument Status
ParameterKey
VLF
Description
Very Low Frequency, VLF, 0.05 to 30 kHz Receiver, Instrument Status: 0=Off, 1=On
Cadence
PT29S
RenderingHints
AxisLabel
VLF
ValueFormat
I1
ScaleMin
0
ScaleMax
1
ValidMin
0
ValidMax
1
FillValue
-2147483648
Support
SupportQuantity
InstrumentMode
Parameter #27
Name
SEA, Instrument Status
ParameterKey
SEA
Description
Spherical Electrostatic Analyzer, SEA, Instrument Status: 0=Off, 1=On
Cadence
PT29S
RenderingHints
AxisLabel
SEA
ValueFormat
I1
ScaleMin
0
ScaleMax
1
ValidMin
0
ValidMax
1
FillValue
-2147483648
Support
SupportQuantity
InstrumentMode
Parameter #28
Name
IMS1, Instrument Status
ParameterKey
IMS1
Description
Ion Mass Spectrometer 1, IMS1, Instrument Status: 0=Off, 1=On
Cadence
PT29S
RenderingHints
AxisLabel
IMS-1
ValueFormat
I1
ScaleMin
0
ScaleMax
1
ValidMin
0
ValidMax
1
FillValue
-2147483648
Support
SupportQuantity
InstrumentMode
Parameter #29
Name
IMS2, Instrument Status
ParameterKey
IMS2
Description
Ion Mass Spectrometer 2, IMS1, Instrument Status: 0=Off, 1=On
Cadence
PT29S
RenderingHints
AxisLabel
IMS-2
ValueFormat
I1
ScaleMin
0
ScaleMax
1
ValidMin
0
ValidMax
1
FillValue
-2147483648
Support
SupportQuantity
InstrumentMode
Parameter #30
Name
SPS, Instrument Status
ParameterKey
SPS
Description
Soft Particle Spectrometer, SPS, Instrument Status: 0=Off, 1=On
Cadence
PT29S
RenderingHints
AxisLabel
SPS
ValueFormat
I1
ScaleMin
0
ScaleMax
1
ValidMin
0
ValidMax
1
FillValue
-2147483648
Support
SupportQuantity
InstrumentMode
Parameter #31
Name
EPD, Instrument Status
ParameterKey
EPD
Description
Energetic Particle Detector, EPD, Instrument Status: 0=Off, 1=On
Cadence
PT29S
RenderingHints
AxisLabel
EPD
ValueFormat
I1
ScaleMin
0
ScaleMax
1
ValidMin
0
ValidMax
1
FillValue
-2147483648
Support
SupportQuantity
InstrumentMode
Parameter #32
Name
Start of Swept Frequency Portion
ParameterKey
swept_start
Description
Scan Line Number of the Start of Swept Frequency Portion of the Ionogram, this seperates the Fixed Frequency and Swept Frequency Portions of the Ionogram
Caveats
seperates the fixed and swept portions
Cadence
PT29S
RenderingHints
AxisLabel
swept_start
ValueFormat
I5
ScaleMin
0
ScaleMax
10000
ValidMin
0
ValidMax
10000
FillValue
-2147483648
Support
Parameter #33
Name
Times of Ionogram Frequency Markers
ParameterKey
Time_mark
Description
Times of Ionogram Frequency Markers, Milliseconds after Frame Sync
Caveats
time of frequency markers This parameter exhibits an increasing monotonic progression.
Cadence
PT29S
Units
ms
UnitsConversion
1e-3>s
RenderingHints
ValueFormat
F10.3
ScaleMin
3000.0
ScaleMax
30000.0
Structure
Size
22
Element
Element
Element
Element
Element
Element
Element
Element
Element
Element
Element
Element
Element
Element
Element
Element
Element
Element
Element
Element
Element
Element
ValidMin
3000.0
ValidMax
30000.0
FillValue
-1.0e+31
Support
Parameter #34
Name
Values of Ionogram Frequency Markers
ParameterKey
freq_mark
Description
Ionogram Frequency Marker Valuess
Cadence
PT29S
Units
MHz
UnitsConversion
1e6>Hz
RenderingHints
ValueFormat
E11.2
ScaleMin
0.1
ScaleMax
20.0
Structure
Size
22
Element
Element
Element
Element
Element
Element
Element
Element
Element
Element
Element
Element
Element
Element
Element
Element
Element
Element
Element
Element
Element
Element
ValidMin
0.0
ValidMax
25.0
FillValue
-1.0e+31
Support
Parameter #35
Name
Number of Delay Times per Ionogram Scan Line
ParameterKey
vh_num
Description
Number of Delay Times per Ionogram Scan Line. Each Sounder Pulse Transmission is followed by a Scan of the Sounder-Receiver Video Amplitude Output Values for each Delay Time monitored after the transmitted Pulse. These Scans are called Scan Lines. There are two Types of ISIS 1 Binary Ionogram Files, one designated as Full and the other designated as Average. The Full File has 1340 Delay Times, one every 0.025 ms. The Average Files are derived from the Full Files by averaging the Amplitude Values in four Delay Time Bins. Thus, the Average Binary Files contain 335 Time Delay Bins within each Scan Line. The CDF Files were made from these Average Binary Files.
Cadence
PT29S
RenderingHints
AxisLabel
N_vh
ValueFormat
I3
ScaleMin
0
ScaleMax
335
ValidMin
0
ValidMax
350
FillValue
-2147483648
Support
Parameter #36
Name
Number of Ionogram Scan Line Frequencies
ParameterKey
f_num
Description
Number of Ionogram Scan Line Frequencie Steps. Ionogram Files can be of different Lengths. In some the Swept Frequency Portion covers the Range from 0.1 Mhz to 10 MHz, in others from 0.1 Mhz to 20 MHz. Also, the proper Start of each Ionogram File, marked by a Frame Sync Pulse, was not always detected during the Analog to Digital, A/D, Conversion. In such cases, a Frame Sync was inserted to limit the File Size. Thus the Number of Sounder-Receiver Video Amplitude versus Delay Time Scan Lines per Ionogram can vary.
Cadence
PT29S
RenderingHints
AxisLabel
N_f
ValueFormat
I6
ScaleMin
0
ScaleMax
4000
ValidMin
0
ValidMax
4000
FillValue
-2147483648
Support
Parameter #37
Name
Delay Time Values
ParameterKey
delay_time
Description
Delay Time Values used in each Scan Line
Cadence
PT29S
Units
ms
UnitsConversion
1e-3>s
RenderingHints
ValueFormat
F9.2
ScaleType
LinearScale
Structure
FillValue
-1.0e+31
Support
Parameter #38
Name
Apparent Range Values
ParameterKey
v_height
Description
Virtual Height Values corresponding to Delay Times used in each Scan Line
Cadence
PT29S
Units
km
UnitsConversion
1e3>m
RenderingHints
ValueFormat
F9.2
ScaleType
LinearScale
Structure
FillValue
-1.0e+31
Support
Qualifier
Magnitude
SupportQuantity
Other
Parameter #39
Name
Epoch Time
ParameterKey
Epoch
Description
Caveats
This parameter exhibits an increasing monotonic progression.
Cadence
PT29S
Units
ms
UnitsConversion
1e-3>s
RenderingHints
AxisLabel
Epoch
ScaleMin
6.2135661819904e+13
ScaleMax
6.3113882619904e+13
ValidMin
01-Jan-1969 00:00:00.000
ValidMax
01-Jan-2000 00:00:00.000
FillValue
-1.0e+31
Support
Parameter #40
Name
Sounder Amplitude
Set
Time series defined by using: EPOCH
ParameterKey
ampl
Description
Sounder Amplitude at 335 Virtual Heights for Fixed Frequency and Swept Frequency, Ionogram. The Sounder-Receiver Linear Video Amplitude, from 0 to 255 Telemetry Units, in each Apparent Range Bin of each Scan Line covering the Fixed Frequency and Swept Frequency Regions. This Range corresponds to a Linear Sounder-Receiver Video Amplitude Output Range from 0 V to 4.5 V. This Calibration is based on the Video Calibration Pulse, of 3.0 V or 170 Telemetry Units, at the End of the Line Scan following each Sounder Pulse. The Combined Calibration Pulses from all of the Line Scans produces a Colored Stripe at the Bottom of the Digital Ionograms. In order to derive an Input Power Level corresponding to the Receiver Video Output, it is necessary to know the Sounder-Receiver Automatic Gain Control, AGC, Voltage. This Voltage was obtained from the Pulse Code Modulation, PCM, Data and thus is only available if PCM Data were available. The AGC Voltage, which ranges from 0 V to 5.12 V, is obtained from a Linear Interpolation between the AGC Trace displayed between the 4005 km Apparent Range, at 26.7 ms Delay Time, as 5.12 V and the 4395 km, at 29.3 ms Delay Time, as 0 V. On the Full Ionograms these Numbers are 4001.250 km or 26.675 ms and 4398.750 km or 29.325 ms. On the Average Ionograms, which are available as either CDF or Binary Files from the SPDF or the NSSDC, the Range Resolution is 0.1 ms, corresponding to a Virtual Range Resolution of 15 km. There are 27 Rows an thus 26 Intervals covering the 0 V to 5.12 V Range; thus each Row in Virtual Range above, i.e. decreasing Delay Time, the Zero Level at 29.3 ms Delay Time corresponds to an Increase of 5.12/26 V of AGC with a Quantization Uncertainty of approximately Plus or Minus 0.1 V. Two Rows have Zero Video Output Amplitude Values on the Average Ionograms in order that a clear AGC Trace is visible on the Ionograms. The Row with the greatest Virtual Range corresponds to the actual AGC Value. On the Full Ionograms, which are only available as Binary Files from the NSSDC, the Range Resolution is 0.025 ms, corresponding to a Virtual Range Resolution of 3.75 km, and three Rows have Zero Video Output Amplitude Values; the middle Row corresponds to the actual AGC Value.
Cadence
PT29S
RenderingHints
Structure
FillValue
-128
Wave
WaveType
PlasmaWaves
Qualifier
Magnitude
Qualifier
Pseudo
WaveQuantity
Intensity
Parameter #41
Name
Interpolated Frequencies
Set
Time series defined by using: EPOCH
ParameterKey
freq
Description
Interpolated Fixed and Swept Frequencies for each Scan Line, in the Swept Frequency Portion of the Ionogram they correspond to interpolated Values between the Frequency Markers
Caveats
This variable could be used as x-axis on amplitude spectrograms if fixed part is subtracted.
Cadence
PT29S
Units
MHz
UnitsConversion
1e6>Hz
RenderingHints
DisplayType
TimeSeries
AxisLabel
Frequency
ValueFormat
E11.2
ScaleMin
0.1
ScaleMax
25.0
ValidMin
0.1
ValidMax
25.0
FillValue
-1.0e+31
Wave
WaveType
PlasmaWaves
Qualifier
Scalar
WaveQuantity
Frequency
Parameter #42
Name
Height
Set
Time series defined by using: EPOCH
ParameterKey
height
Description
Caveats
Virtual variable. This parameter is virtual. It is calculated by calling the function HEIGHT_ISIS with the following input parameters: geo_coord.
Cadence
PT29S
Units
km
UnitsConversion
1e3>m
RenderingHints
DisplayType
TimeSeries
AxisLabel
Satellite Altitude
ValueFormat
F6.1
ScaleMin
0.0
ScaleMax
4000.0
ValidMin
0.0
ValidMax
4000.0
FillValue
-1.0e+31
Support
Qualifier
Magnitude
SupportQuantity
Positional
Parameter #43
Name
Electron Local Gyrofrequency
Set
Time series defined by using: EPOCH
ParameterKey
FH
Description
Electron Local Gyrofrequency, at the Time of Ionogram Frame Sync
Cadence
PT29S
Units
MHz
UnitsConversion
1e6>Hz
RenderingHints
DisplayType
TimeSeries
AxisLabel
Electron Gyrofrequency
ValueFormat
F7.3
ScaleMin
0.0
ScaleMax
100.0
ValidMin
0.0
ValidMax
100.0
FillValue
-1.0e+31
Particle
ParticleType
Electron
ParticleQuantity
Gyrofrequency