multistaticIntegrationTimes: Incoherent integration time estimation

In ilkkavir/ISgeometry: ISgeometry

Incoherent integration time estimation

Description

Incoherent integration time required to reach a given ACF noise level in given points in space.

The radar beams are modelled as 3D normal distributions to enable fast calculations.

See references for definition of the ACF noise level.

Usage

       multistaticIntegrationTimes(
        refPoint = SKI,
        locTrans = SKI,
          locRec = list(SKI,KAR,KAI),
           locxy = FALSE,
       fwhmTrans = c(2.2),
         fwhmRec = c(1.3,1.8,1.8),
       fwhmRange = c(1),
               x = seq(-300,300,by=25),
               y = seq(-300,300,by=25),
         heights = c(300),
        infinity = defaultInfinity(),
           resNS,
           resEW,
            resH,
            resR,
              Pt = c(3.5e6),
              Ne = 1e11,
     fwhmIonSlab = 100,
          Tnoise = c(300),
          fradar = 233e6,
            tau0 = 100,
      phArrTrans = TRUE,
        phArrRec = TRUE,
targetNoiseLevel = .01,
       dutyCycle = .25,
          RXduty = 1,
            gdev = NULL,
            zlim = c(0,5),
           zlimv = c(2,7),
      iso.levels = c(.1,.3,.7,1,3,7,10,33,67,100,333,667,1000,3333,6667,10000,33333,666667,1000000,3333333,6666667,1e7,3e7,7e7,1e8,3e8,7e8,1e9),
      vel.levels = c(.1,.3,.7,1,3,7,10,33,67,100,333,667,1000,3333,6667,10000,33333,666667,1000000,3333333,6666667,1e7,3e7,7e7,1e8,3e8,7e8,1e9),
       printInfo = FALSE,
  plotResolution = FALSE,
           NScut = 0,
          horCut = TRUE,
         verbose = FALSE,
     mineleTrans = 30,
       mineleRec = 30,
       useRaster = FALSE
       )

Arguments

refPoint	c(lat,lon) reference point from which the distance x and y are measured
locTrans	list(c(lat,lon)) or list(c(lat,lon,height)) latitudes, longitudes (and heights) of the transmitter antennas. Angles in degrees. OR list(c(x,y)) position of the transmitter, IF locxy=T
locRec	list(c(lat,lon)) or list(c(lat,lon,height)) latitudes, longitudes (and heights) of the receiver antennas. Angles in degrees. OR list(c(x,y)) IF locxy=T
locxy	logical, if T, the positions of the transmitter and receiver are given in cartesian coordinates, otherwise in latitudes and longitudes
fwhmTrans	c(fwhmTrans1,fwhmTrans2,...) full width at half maximum of the transmitter beams when pointed to zenith, in degrees. If only one value is given, it is used for all transmitters.
fwhmRec	c(fwhmRec1,fwhmRec2,...) full width at half maximum of the receiver beams when pointed to zenith, in degrees. If only one value is given, it is used for all receivers.
fwhmRange	c(fwhmRange1,fwhmRange2,...) full width at half maximum of the gaussian range ambiguity function [km]. If only one value is given, it is used for all transmitters.
x	vector of grid points in West-East direction, relative to the reference point.
y	vector of grid points in North-South direction, relative to the reference point.
heights	vector of grid points in vertical direction, in kilometers. Separate maps are plotted for each height.
infinity	a large value used as standard deviation along the beam direction
resNS	(optional) north-south resolution of the integrated resolution cells [km]
resEW	(optional) east-west resolution of the integrated resolution cells [km]
resH	(optional) height resolution of the integrated resolution cells [km]
resR	(optional) integrated range resolution [km], used if some of the above three is not given. If missing, the resolution is matched with fwhmRange
Pt	c(Pt1,Pt2,...) transmitter powers [W]. If only one value is given, it is used for all transmitters.
Ne	electron density [m^-3]
fwhmIonSlab	Slab thickness of the ionosphere. Used in self-noise estimation
Tnoise	system noise temperatures of the receivers [K]. If only one value is given, it is used for all receivers.
fradar	radar carrier frequency [Hz]
tau0	ACF time-scale [us]
phArrTrans	logical, if TRUE, phased-array antennas with beam widening as function of tilt angle are assumed, otherwise beam width does not depend on pointing direction. If only one value is given, it is used for all transmitters.
phArrRec	logical, if TRUE, phased-array antennas with beam widening as function of tilt angle are assumed, otherwise beam width does not depend on pointing direction. If only one value is given, it is used for all receivers.
targetNoiseLevel	target noise level value, same target value used for both isotropic and velocity integration times
dutyCycle	transmitter duty cycle
RXduty	"Receiver duty cycle"
gdev	graphics device used for plotting; default for Mac OS X is 'quartz', for Unix/Linux 'X11' and for Windows 'windows'.
zlim	zlim for the plots of isotropic parameter integration times
zlimv	zlim for the plots of velocity integration times
iso.levels	contour line levels for isometric parameter plot
vel.levels	contour line levels for velocity plot
printInfo	logical; if T, plots used parameters below the map plot
plotResolution	logical; if T,plots resolution map in addition to the isotropic and velocity integration time maps.
plotResolution	logical; if T, plots resolution map in addition to the isotropic and velocity integration time maps.
NScut	a vector of indices of north-south directed vertical slices to plot. nothing will be plotted if NScut <= 0
horCut	if FALSE, the plots of horisontal cuts will not be produced. Useful e.g. when producing only a single vertical cut with x=c(0).
verbose	optional printing of average SNR / power etc.
mineleTrans	mimimum allowed elevation for transmitter(s) in degrees [0 90]
mineleRec	minimum allowed elevation for receiver(s) in degrees [0 90]
useRaster	rasterize images? Works only with regular grids!

Value

Plots integration time maps for isotropic parameters and velocity. Optionally, if plotResolution is TRUE, also plots the resolution map. If called with a return variable, returns a list of noise levels, integration times, resolutions, etc. at the grid points.

Author(s)

Ilkka Virtanen (University of Oulu, Finland) [e-mail]

References

1. Matti Vallinkoski, Statistics of incoherent scatter multiparameter fits, Journal of Atmospheric and Terrestrial Physics, 50 (9), 839-851, 1988, https://doi.org/10.1016/0021-9169(88)90106-7

2. Markku Lehtinen, Ilkka I. Virtanen, and Mikko R. Orispää, EISCAT_3D Measurement Methods Handbook, 2014, http://urn.fi/urn:isbn:9789526205854

Examples

## EISCAT 3D system with the default values
multistaticIntegrationTimes()

## Four remotes plus a core transmit/receive site at Kiruna. Positions
## given in the xy-coordinate system:

multistaticIntegrationTimes(x=seq(-300,300,by=25),y=seq(-300,300,by=25),locTrans=c(0,0),locRec=list(c(0,0),c(-200,0),c(200,0),c(0,-200),c(0,200)),refPoint=KIR,locxy=T,Tnoise=c(100,40,40,40,40,40),heights=c(100,300,500),fwhmTrans=.6,fwhmRec=.6)


## save figure number 3 as pdf file "figure3.pdf"

savepdf(3,'figure3.pdf')


## evalution of the EISCAT UHF system assuming 10 x 10 x 10 km
## resolution cells
multistaticIntegrationTimes(x=seq(-300,300,by=25),y=seq(-300,300,by=25),locTrans=TRO,locRec=list(TRO,KIR,SOD),refPoint=KIR,locxy=F,Tnoise=c(100,40,40),heights=c(100,300,500),fwhmTrans=.6,fwhmRec=.6,phArr=F,resNS=10,resEW=10,resH=10)


## Using both steerable and phased arrays
multistaticIntegrationTimes(locTrans=list(KIR,SOD,KIL,JAR,KAU),locRec=list(MUO,OVE,KIR,SOD,KIL),phArrTrans=c(T,T,T,F,F),phArrRec=c(F,F,T,F,T),locxy=FALSE)

ilkkavir/ISgeometry documentation built on Jan. 19, 2025, 5:26 p.m.