Band pass filtering of time series data
Hello, I am trying to replicate this study that filters the time series of the H-component of the magnetic field in the period range of 10-45 seconds to see ultralow frequency variations around the time of an earthquake or volcanic event, so may I ask anyone how to use the bandpass function in MATLAB right in this case?
Here’s my silly attempt
fs = 1/60; %since the data is per minute
bandpass(T.DAVH,[0.022 0.1],fs); % period range of 10-45 seconds to frequency in Hz
but it returns
Warning: Specified passband frequency is beyond the Nyquist range so signal has been
filtered with an allstop filter.
> In highpass>designFilter (line 129)
In highpass (line 97)
In bandpass>performHighpassFiltering (line 149)
In bandpass (line 116)
Attached the data below where T.DAVH is the H-component of the magnetic field measured in Davao station.
The description of the data is as follows:
Format IAGA-2002 |
Source of Data Kyushu University (KU) |
Station Name Davao |
IAGA CODE DAV (KU code) |
Geodetic Latitude 007.000 |
Geodetic Longitude 125.400 |
Elevation 8888.88 |
Reported HDZF |
Sensor Orientation HDZ |
Digital Sampling 1 seconds |
Data Interval Type Averaged 1-minute (00:30 – 01:29) |
Data Type Provisional
Thank you to anyone who can help!Hello, I am trying to replicate this study that filters the time series of the H-component of the magnetic field in the period range of 10-45 seconds to see ultralow frequency variations around the time of an earthquake or volcanic event, so may I ask anyone how to use the bandpass function in MATLAB right in this case?
Here’s my silly attempt
fs = 1/60; %since the data is per minute
bandpass(T.DAVH,[0.022 0.1],fs); % period range of 10-45 seconds to frequency in Hz
but it returns
Warning: Specified passband frequency is beyond the Nyquist range so signal has been
filtered with an allstop filter.
> In highpass>designFilter (line 129)
In highpass (line 97)
In bandpass>performHighpassFiltering (line 149)
In bandpass (line 116)
Attached the data below where T.DAVH is the H-component of the magnetic field measured in Davao station.
The description of the data is as follows:
Format IAGA-2002 |
Source of Data Kyushu University (KU) |
Station Name Davao |
IAGA CODE DAV (KU code) |
Geodetic Latitude 007.000 |
Geodetic Longitude 125.400 |
Elevation 8888.88 |
Reported HDZF |
Sensor Orientation HDZ |
Digital Sampling 1 seconds |
Data Interval Type Averaged 1-minute (00:30 – 01:29) |
Data Type Provisional
Thank you to anyone who can help! Hello, I am trying to replicate this study that filters the time series of the H-component of the magnetic field in the period range of 10-45 seconds to see ultralow frequency variations around the time of an earthquake or volcanic event, so may I ask anyone how to use the bandpass function in MATLAB right in this case?
Here’s my silly attempt
fs = 1/60; %since the data is per minute
bandpass(T.DAVH,[0.022 0.1],fs); % period range of 10-45 seconds to frequency in Hz
but it returns
Warning: Specified passband frequency is beyond the Nyquist range so signal has been
filtered with an allstop filter.
> In highpass>designFilter (line 129)
In highpass (line 97)
In bandpass>performHighpassFiltering (line 149)
In bandpass (line 116)
Attached the data below where T.DAVH is the H-component of the magnetic field measured in Davao station.
The description of the data is as follows:
Format IAGA-2002 |
Source of Data Kyushu University (KU) |
Station Name Davao |
IAGA CODE DAV (KU code) |
Geodetic Latitude 007.000 |
Geodetic Longitude 125.400 |
Elevation 8888.88 |
Reported HDZF |
Sensor Orientation HDZ |
Digital Sampling 1 seconds |
Data Interval Type Averaged 1-minute (00:30 – 01:29) |
Data Type Provisional
Thank you to anyone who can help! signal processing, bandpass filtering, bandpass MATLAB Answers — New Questions
