guidelines for band code assignment
Sleeman, Reinoud (KNMI)
During the preparation for the next WG II meeting in Melbourne I noticed
the following request made by Doug Neuhauser, upon which our WG never
took
further action (?).
A pragmatic solution would be to keep the current band code in place for
the
seismometers and define new ones for accelerometers and other
geophysical instruments
based on the sample rate only, for example:
I sr >= 1000 Hz
J sr: 250 Hz - 1000 Hz
K sr: 100 Hz - 250 Hz
N sr: 1 Hz - 10 Hz
P sr: ~ 1 Hz
W sr: ~ 0.1 Hz
X sr: ~ 0.01 Hz
Y sr < 0.01 Hz
Please let me know your thoughts.
I will send you a draft agenda for the WG II meeting today or tomorrow.
Cheers,
Reinoud
> From: Doug Neuhauser <doug at seismo.berkeley.edu>
> Date: December 24, 2008 12:36:07 PM PST
> Subject: SEED band code clarification requested
>
> The SEED manual (Appendix A) provides some guidelines for band code
> assignment based on sample rate, and for higher sampling rate, based
> on corner frequency. These have recently been extended to define
> band codes for higher sample rates based on the same corner frequency
> guidelines.
>
> Band Band type Sample rate Corner period
> code (sec)
> ---------------------------------------------------------------------
> B Broad band >= 10 to < 80 >= 10 sec
> H High Broad Band >= 80 to < 250 >= 10 sec
> C ... >= 250 to < 1000 >= 10 sec
> F ... >= 1000 to < 5000 >= 10 sec
>
> S Short Period >= 10 to < 80 < 10 sec
> E Extreme Short Period >= 80 to < 250 < 10 sec
> D ... >= 250 to < 1000 < 10 sec
> G ... >= 1000 to < 5000 < 10 sec
>
> I and others in the SEED community would like some clarification and
guidance
> on what the term "Corner period (sec)" refers to. Specifically, it is
not
> clear into which of the above "corner period" categories data from
> accelerometers and other geophysical instruments such as electric and
magnetic
> field sensors should be classified.
>
> For traditional accelerometers:
> If the "corner period in seconds" refers to the lower corner of the
flat
> passband of the measured observation (eg acceleration for an
accelerometer),
> then I would infer that accelerometers should be classified along with
> "broadband" sensors in the first group of band codes where the corner
period
> of >= 10 seconds, since the response of acceleromters is flat to ~DC
(0 Hz ~=
> infinity seconds). However, if the corner period in seconds refers to
the
> natural period of the actual sensor, most accelerometers have a
natural period
> of several Hz (< 1 second), from which I would infer that they should
be
> classified with "short period" on the second group of band codes with
a corner
> period of < 10 seconds. If the corner period is based on the
characteristics
> of the physical sensor, and not of the property of the data produced
by the
> sensor, it is unclear how this may change for non-traditional sensors
such as
> silicon-based or fluid sensors.
>
> It sould be extremely helpful to have additional guidelines to help
> the SEED community standardize on channel names. Currently, I have
> seen both E and H bandcodes uses for 100 Hz accelerometer data,
> and the same confusion exists for higher sample rates.
>
> For other geophysical data channels such as electric and magentic
field
> sensors, the same question arises. For both electric and magnetic
field data
> channels, the response of data channels are often flat to close to DC,
so I
> would infer that they should be classified along with the broad band
sensors.
> However, if the classification is based on the senor characteristics,
it is is
> not clear what characteristics of the actual sensor you would use for
classification.
>
Winfried Hanka
according to the SEED manual it looks like band code P is already taken for
sr :"on the order of 0.1 to 1 day* ≥ 0.00001 to < 0.0001"
I am not sure if anybody is using it though. Otherwise I have no objections.
Regards,
Winfried
On 06/21/11 15:05, Sleeman, Reinoud (KNMI) wrote:
> Dear WG II members,
>
>
>
> During the preparation for the next WG II meeting inMelbourne I noticed
>
> the following request made by Doug Neuhauser, upon which our WG never took
>
> further action (?).
>
>
>
> A pragmatic solution would be to keep the current band code in place for the
>
> seismometers and define new ones for accelerometers and other geophysical instruments
>
> based on the sample rate only, for example:
>
>
>
> I sr>= 1000 Hz
>
> J sr: 250 Hz– 1000 Hz
>
> K sr: 100 Hz– 250 Hz
>
> N sr: 1 Hz– 10 Hz
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