% Generated by roxygen2: do not edit by hand
% Please edit documentation in R/WetDryNearbyLinkApMinMaxRSL.R
\name{WetDryNearbyLinkApMinMaxRSL}
\alias{WetDryNearbyLinkApMinMaxRSL}
\title{Function for classifying wet and dry periods according to the nearby link approach. 
Function also prepares link data for determination of reference signal level and for 
computing corrected received powers.}
\usage{
WetDryNearbyLinkApMinMaxRSL(
  Data,
  InputCoorSystem = InputCoorSystem,
  LocalCartesianCoorSystem = LocalCartesianCoorSystem,
  MinHoursPmin = 6,
  PeriodHoursPmin = 24,
  Radius = 15,
  Step8 = TRUE,
  ThresholdMedian = -1.4,
  ThresholdMedianL = -0.7,
  ThresholdNumberLinks = 3,
  ThresholdWetDry = 2
)
}
\arguments{
\item{Data}{Data frame with microwave link data.}

\item{InputCoorSystem}{Define EPSG code for input coordinate system (e.g., 4326L for WGS84 in degrees).}

\item{LocalCartesianCoorSystem}{Define EPSG code for (local) Cartesian coordinate system (meters).}

\item{MinHoursPmin}{Minimum number of hours in the previous PeriodHoursPmin hours needed 
for computing max(P\eqn{_{\mbox{min}}}) (h).}

\item{PeriodHoursPmin}{Number of hours that is considered for computation of 
max(P\eqn{_{\mbox{min}}}) (h).}

\item{Radius}{Radius in wet-dry classification (km).}

\item{Step8}{If TRUE step 8 in the wet-dry classification is performed, else it is not executed.}

\item{ThresholdMedian}{Threshold value (dB).}

\item{ThresholdMedianL}{Threshold value (dB km\eqn{^{-1}}).}

\item{ThresholdNumberLinks}{Only use data if number of available (surrounding) links is at least larger than this 
threshold for the time interval under consideration. The selected link is also counted.}
}
\value{
Data frame: Should interval be considered dry for reference level.
determination? (0 = wet; 1 = dry)

Values F for filter to remove outliers (dB km\eqn{^{-1}} h)
}
\description{
The received signal powers often decrease during non-rainy periods, 
resulting in non-zero rainfall estimates, e.g. caused by reflection of the beam or dew 
formation on the antennas. To prevent this rainfall overestimation a reliable 
classification of wet and dry periods is needed. This is also beneficial for 
determining an appropriate reference signal level, representative for dry weather. 
In order to define wet and dry periods, we assume that rain is correlated in space, and 
hence that several links in a given area should experience a decrease in minimum received signal 
level in the case of rain. A time interval is labeled as wet if at least half of the links 
in the vicinity (for chosen radius) of the selected link experience such a decrease. This 
so called nearby link approach is applied in this function. The function also prepares 
link data for determination of reference signal level and for computing corrected received 
powers. 

Works for a sampling strategy where minimum and maximum received signal powers
are provided, and the transmitted power levels are constant.

Also works for a sampling strategy where instantaneous transmitted and received signal levels are obtained.
In case of instantaneous signal levels, it does not matter whether transmitted power levels vary or are constant.
The only requirement is that the input data for RAINLINK needs some preprocessing. See ''ManualRAINLINK.pdf''
for instructions. 

Also works for a sampling strategy where average transmitted and received signal levels are obtained.
In case of average signal levels, it does not matter whether transmitted power levels vary or are constant.
The only requirement is that the input data for RAINLINK needs some preprocessing. See ''ManualRAINLINK.pdf''
for instructions. 

The time interval does not have to be an integer but should be equidistant. The minimum time 
interval length in the time series is automatically computed and is employed as the time 
interval length.
}
\examples{
WetDryNearbyLinkApMinMaxRSL(Data=DataPreprocessed,InputCoorSystem=4326L,
LocalCartesianCoorSystem=28992, MinHoursPmin=6,PeriodHoursPmin=24,Radius=15,
Step8=TRUE,ThresholdMedian=-1.4, ThresholdMedianL=-0.7,ThresholdNumberLinks=3,
ThresholdWetDry=2)
}
\references{
''ManualRAINLINK.pdf''

Overeem, A., Leijnse, H., and Uijlenhoet, R., 2016: Retrieval algorithm for rainfall mapping from microwave links in a 
cellular communication network, Atmospheric Measurement Techniques, 9, 2425-2444, https://doi.org/10.5194/amt-9-2425-2016.
}
\author{
Aart Overeem & Hidde Leijnse
}