ISCE_INSAR/components/stdproc/orbit/orbitLib/CalcSchHeightVel.py

296 lines
10 KiB
Python
Executable File

#!/usr/bin/env python3
#~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
# Copyright 2010 California Institute of Technology. ALL RIGHTS RESERVED.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
#
# United States Government Sponsorship acknowledged. This software is subject to
# U.S. export control laws and regulations and has been classified as 'EAR99 NLR'
# (No [Export] License Required except when exporting to an embargoed country,
# end user, or in support of a prohibited end use). By downloading this software,
# the user agrees to comply with all applicable U.S. export laws and regulations.
# The user has the responsibility to obtain export licenses, or other export
# authority as may be required before exporting this software to any 'EAR99'
# embargoed foreign country or citizen of those countries.
#
# Author: Giangi Sacco
#~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
import logging
import math
from iscesys.Compatibility import Compatibility
from isceobj.Planet import Planet
from isceobj import Constants as CN
from iscesys.Component.Component import Component, Port
RANGE_SAMPLING_RATE = Component.Parameter('rangeSamplingRate',
public_name='range sampling rate',
type=float,
default=None,
units='Hz',
mandatory=True,
doc="Sampling rate in range"
)
PRF = Component.Parameter('prf',
public_name='prf',
type=float,
default=None,
units='Hz',
mandatory=True,
doc="Pulse repetition frequency"
)
RANGE_FIRST_SAMPLE = Component.Parameter('rangeFirstSample',
public_name='range to first sample',
type=float,
default=None,
units='meter',
mandatory=True,
doc="Range in meters to the first sample"
)
class CalcSchHeightVel(Component):
parameter_list = (RANGE_SAMPLING_RATE,
PRF,
RANGE_FIRST_SAMPLE)
def calculate(self):
for port in self.inputPorts:
port()
self.b = self.a*math.sqrt(1-self.e2)
ro = self.rangeFirstSample
sol = CN.SPEED_OF_LIGHT
rc = self.b
ra = self.a
fs = self.rangeSamplingRate
dt = 1/self.prf
dr = 1/2.*sol/fs
half = len(self.pos)//2 - 1
xyz = self.pos[half]
vxyz = self.vel[half]
rs = math.sqrt(xyz[0]*xyz[0] + xyz[1]*xyz[1] + xyz[2]*xyz[2])
vs = math.sqrt(vxyz[0]*vxyz[0] + vxyz[1]*vxyz[1] + vxyz[2]*vxyz[2])
rlat = math.asin(xyz[2]/rs)
rlatg = math.atan(math.tan(rlat)*ra*ra/(rc*rc))
st = math.sin(rlatg)
ct = math.cos(rlatg)
arg = (ct*ct)/(ra*ra) + (st*st)/(rc*rc)
re = 1./math.sqrt(arg)
try:
re = self.pegRadCur
except:
pass
# compute the vector orthogonal to both the radial vector and velocity vector */
a = [xyz[0]/rs,xyz[1]/rs,xyz[2]/rs]
b = [vxyz[0]/vs,vxyz[1]/vs,vxyz[2]/vs]
# cross product
c = [(a[1]*b[2]) - (a[2]*b[1]),(-a[0]*b[2]) + (a[2]*b[0]),(a[0]*b[1]) - (a[1]*b[0])]
# /* compute the look angle */
ct = (rs*rs+ro*ro-(re+self.terrainHeight)**2)/(2.*rs*ro)
st = math.sin(math.acos(ct))
# /* add the satellite and LOS vectors to get the new point */
xe = xyz[0]+ro*(-st*c[0]-ct*a[0])
ye = xyz[1]+ro*(-st*c[1]-ct*a[1])
ze = xyz[2]+ro*(-st*c[2]-ct*a[2])
rlat = math.asin(ze/re)
rlatg = math.atan(math.tan(rlat)*ra*ra/(rc*rc))
# /* compute elipse height in the scene */
st = math.sin(rlatg)
ct = math.cos(rlatg)
arg = (ct*ct)/(ra*ra)+(st*st)/(rc*rc)
re = 1./(math.sqrt(arg))
self.height = rs - re
# /* now check range over time */
#jng the original code claims that it uses the center +- 2 sec to compute the velocity. it skips 10000 lines from the beginning and the end, which is about 8000 lines in the center. this is 2.4 sec. default the self.offset to be close to 2.4 sec.
offset = int(self.offset*self.prf)
lo = max(half-offset,0)
hi = min(half+offset,2*half)
#lo = 10000
#hi = len(self.pos) - 10000
rng = [0]*(hi-lo)
cnt = 0
for i in range(lo,hi):
rng[cnt] = math.sqrt((xe-self.pos[i][0])*(xe-self.pos[i][0]) + (ye-self.pos[i][1])*(ye-self.pos[i][1]) + (ze-self.pos[i][2])*(ze-self.pos[i][2])) - ro
cnt += 1
sumdr = 0
for i in range(1,len(rng)-1):
sumdr += rng[i+1] + rng[i-1] -2*rng[i]
sumdr /= (len(rng)-2)*dt*dt
self.velocity = math.sqrt(ro*math.fabs(sumdr))
return None
## You need this identity to use Componenet.__call__
calcschheightvel = calculate
def setRangeFirstSample(self,rfs):
self.rangeFirstSample = rfs
def setRangeSamplingRate(self,rsr):
self.rangeSamplingRate = rsr
def setPRF(self,prf):
self.prf = prf
def setPosition(self,pos):
self.pos = pos
def setVelocity(self,vel):
self.vel = vel
def setOffest(self,off):
self.offset = off
def setEllipsoidMajorAxis(self,a):
self.a = a
def setEllipsoidEccentricitySquared(self,e2):
self.e2 = e2
def getHeight(self):
return self.height
def getVelocity(self):
return self.velocity
def addOrbit(self):
orbit = self._inputPorts.getPort('orbit').getObject()
if (orbit):
try:
(time,position,velocity,offset) = orbit._unpackOrbit()
self.pos = position
self.vel = velocity
except AttributeError:
self.logger.error("Object %s requires an _unpackOrbit() method" % (orbit.__class__))
raise AttributeError
def addFrame(self):
frame = self._inputPorts.getPort('frame').getObject()
if (frame):
try:
self.rangeFirstSample = frame.getStartingRange()
instrument = frame.getInstrument()
self.rangeSamplingRate = instrument.getRangeSamplingRate()
self.prf = instrument.getPulseRepetitionFrequency()
except AttributeError as strerr:
self.logger.error(strerr)
raise AttributeError
try:
self.terrainHeight = frame.terrainHeight
self.pegRadCur = frame._ellipsoid.pegRadCur
except:
self.terrainHeight = 0.0
def addPlanet(self):
planet = self._inputPorts.getPort('planet').getObject()
if (planet):
try:
ellipsoid = planet.get_elp()
self.a = ellipsoid.get_a()
self.e2 = ellipsoid.get_e2()
except AttributeError as strerr:
self.logger.error(strerr)
raise AttributeError
logging_name = "CalcSchHeightVel"
def __init__(self):
super(CalcSchHeightVel, self).__init__()
planet = Planet.Planet(pname='Earth')
ellipsoid = planet.get_elp()
self.a = ellipsoid.get_a()
self.e2 = ellipsoid.get_e2()
self.b = None
self.rangeFirstSample = None
self.rangeSamplingRate = None
self.prf = None
self.height = None
self.velocity = None
self.prf = None
self.pos = None
self.vel = None
self.offset = 2.3758
self.terrainHeight = 0.0
# self.logger = logging.getLogger("CalcSchHeightVel")
# self.createPorts()
self.dictionaryOfOutputVariables = {
'HEIGHT' : 'height' ,
'VELOCITY' : 'velocity'
}
# TODO: 'radius' does not exist as an member of this class
# 'RADIUS' : 'radius' \
# }
self.descriptionOfVariables = {}
self.mandatoryVariables = []
self.optionalVariables = []
self.initOptionalAndMandatoryLists()
return None
def createPorts(self):
orbitPort = Port(name='orbit',method=self.addOrbit)
framePort = Port(name='frame',method=self.addFrame)
planetPort = Port(name='planet',method=self.addPlanet)
self._inputPorts.add(orbitPort)
self._inputPorts.add(framePort)
self._inputPorts.add(planetPort)
return None
pass
def main():
import pdb
pdb.set_trace()
with open(sys.argv[1]) as fp:
allL = fp.readlines()
numberOfLines = len(allL)
position = []
velocity = []
for i in range(numberOfLines):
line = allL[i].split()
position.append([float(line[2]),float(line[3]),float(line[4])])
velocity.append([float(line[5]),float(line[6]),float(line[7])])
ch = CalcSchHeightVel()
ch.setPosition(position)
ch.setVelocity(velocity)
ch.setPRF(1741.71924)
ch.setRangeFirstSample(955972.779)
ch.setRangeSamplingRate(19207680.)
ch.calculate()
if __name__ == '__main__':
import sys
sys.exit(main())