beam_profile: Calculate vertical radiation profile

In adokter/birdRad: Biological Analysis and Visualization of Weather Radar Data

Calculate vertical radiation profile

Description

Calculates for a set of beam elevations (elev) the altitudinal normalized distribution of radiated energy by those beams. Is a function of altitude (height) at a given distance (distance) from the radar, assuming the beams are emitted at antenna level

Usage

beam_profile(
  height,
  distance,
  elev,
  antenna = 0,
  beam_angle = 1,
  k = 4/3,
  lat = 35,
  re = 6378,
  rp = 6357
)

Arguments

height	Numeric. Height in m.
distance	Numeric. Distance from the radar as measured along sea level (down range), in m.
elev	Numeric vector. Beam elevation(s), in degrees.
antenna	Numeric. Height of the centre of the radar antenna, in m.
beam_angle	Numeric. Beam opening angle in degrees, typically the angle between the half-power (-3 dB) points of the main lobe.
k	Numeric. Standard refraction coefficient.
lat	Numeric. Geodetic latitude of the radar, in degrees.
re	Numeric. Earth equatorial radius, in km.
rp	Numeric. Earth polar radius, in km.

Details

Beam profile is calculated using beam_height and beam_width. Returns a beam profile as a function of height relative to ground level.

Returns the normalized altitudinal pattern of radiated energy as a function of altitude at a given distance from the radar, assuming the beams are emitted at antenna level.

Value

Numeric vector. Normalized radiated energy at each of the specified heights.

See Also

Other beam_functions: beam_distance(), beam_height(), beam_profile_overlap(), beam_range(), beam_width(), gaussian_beam_profile()

Examples

# Plot the beam profile, for a 0.5 degree elevation beam at 50 km distance
# from the radar:
plot(beam_profile(height = 0:4000, 50000, 0.5), 0:4000,
  xlab = "normalized radiated energy",
  ylab = "height [m]", main = "beam elevation: 0.5 deg, distance=50km"
)

# Plot the beam profile, for a 2 degree elevation beam at 50 km distance
# from the radar:
plot(beam_profile(height = 0:4000, 50000, 2), 0:4000,
  xlab = "normalized radiated energy",
  ylab = "height [m]", main = "beam elevation: 2 deg, distance=50km"
)

# Plot the combined beam profile for a 0.5 and 2.0 degree elevation beam
# at 50 km distance from the radar:
plot(beam_profile(height = 0:4000, 50000, c(0.5, 2)), 0:4000,
  xlab = "normalized radiated energy",
  ylab = "height [m]", main = "beam elevations: 0.5,2 deg, distance=50km"
)

adokter/birdRad documentation built on Nov. 5, 2024, 10:27 p.m.