signal_deconvolve function

Deconvolve a signal vector.

The function removes the instrument response from a signal vector.

signal_deconvolve(
  data,
  xml,
  sensor = "TC120s",
  logger = "Cube3BOB",
  gain = 1,
  use_metadata = FALSE,
  dt,
  url,
  xml_use,
  p = 10^-6,
  waterlevel = 10^-6,
  na.replace = FALSE,
  verbose = FALSE
)

Arguments

• data: eseis object, numeric vector or list of objects, data set to be processed.

• xml: station XML file to use, either an obspy object or path to a XML file. If provided, all other station parameters will be ignored and the station XML file will be used. Currently, the station XML approach is only supported through Obspy and when eseis objects are provided. In that case, lists of eseis cannot be supported.

• sensor: Character value or list object, seismic sensor name. Must be present in the sensor library (list_sensor) or parameters must be added manually (see examples). Default is "TC120s".

• logger: Character value, seismic logger name. Must be present in the logger library (list_logger) or parameters must be added manually. Default is "Cube3extBOB".

• gain: Numeric value, signal gain level of the logger. Default is 1.

• use_metadata: Logical value, option to take keywords for sensor, logger and gain from eseis object meta data element instead of using explicitly provided arguments. Default is FALSE.

• dt: Numeric value, sampling rate. Only needed if data

  is not an eseis object

• url: Character value, URL of the FDSN data provider. Should be of the form "http://service.iris.edu", i.e., without further URL parts. URLs can be submitted as a vector. See aux_getxml for further details. Only needed when XML file is to be downloaded.

• xml_use: Logical value, only needed internally, will be set automatically.

• p: Numeric value, proportion of signal to be tapered. Default is10^-6.

• waterlevel: Numeric value, waterlevel value for frequency division, default is 10^-6.

• na.replace: Logical value, option to replace NA values in the data set by zeros. Default is FALSE. Attention, the zeros will create artifacts in the deconvolved data set. However, NA values will result in no deconvolution at all.

• verbose: Logical value, option to allow messages and warnings to be shown. Default is FALSE.

Returns

Numeric vector or list of vectors, deconvolved signal.

Details

The function requires a set of input parameters, apart from the signal vector. These parameters are contained in and read from the function list_sensor() and list_logger(). Poles and zeros are used to build the transfer function. The value s is the generator constant in Vs/m. The value k is the normalisation factor. AD is the analogue-digital conversion factor n Volts per count. If the signal was recorded with a gain value other than 1, the resulting signal needs to be corrected for this, as well. As of v. 0.8.0, the function also supports deconvolution using the station XML scheme. However, that feature is implemented through the python toolbox Obspy, which needs to be installed separately.

Examples

## load example data set
data(rockfall)

## deconvolve signal with minimum effort
rockfall_decon <- signal_deconvolve(data = rockfall_eseis)

## plot time series
plot_signal(data = rockfall_decon, 
     main = "Rockfall, deconvolved signal", 
     ylab = "m/s")
 
## add new logger manually
logger_new <- list_logger()[[1]]

## add logger data
logger_new$ID <- "logger_new"
logger_new$name <- "logger_new"
logger_new$AD <- 2.4414e-07

## deconvolve signal with new logger
rockfall_decon <- signal_deconvolve(data = rockfall_eseis,
                                    sensor = "TC120s", 
                                    logger = logger_new)

## Change the setup of a logger, here: Centaur AD is changed due to 
## other than default Vpp value, according to AD = V / (2^24).

## extract default Centaur logger
Centaur_10V <- list_logger()[[2]]

## replace AD value
Centaur_10V$AD <- 20/(2^24)

## Not run:

## working with station XML files:

## download and import example data set
s <- read_fdsn(start = "2023-06-10", 
               duration = 600, 
               station = "DAVA", 
               network = "OE",
               component = "BHZ")

## download and save station XML file
xml <- aux_getxml(xml = "OE.DAVA.XML",
                  start = "2023-06-10",
                  duration = 600,
                  network = "OE",
                  station = "DAVA",
                  component = "BHZ",
                  url = "http://service.iris.edu")

## deconvolve data set with downloaded XML file
s_d <- signal_deconvolve(data = s, 
                         xml = "OE.DAVA.XML")
                         
## alternatively, deconvolve data set by online XML file (no saving)
s_d <- signal_deconvolve(data = s, 
                         xml = TRUE,
                         url = "http://service.iris.edu")
## End(Not run)

Author(s)

Michael Dietze