def main():
# ==========================================================================
# Telescope element radii
st_radius = 35.0 / 2.0 # Station-radius
ss_radius = st_radius * 3.0 # Super-station radius
# Core ring super-stations
num_rings = 4
ring_counts = [1, 5, 11, 17]
ring_radii = [0.0, 100.0, 190.0, 290.0] # metres
num_super_stations_rings = numpy.array(ring_counts).sum()
ring_start_angle = -360.0 * random(num_rings) + 360.0
ss_ring_petal_angle = -360.0 * random(num_super_stations_rings) + 360.0
# Core arms
num_arms = 3
core_arm_count = 5 # Number of super-stations per core arm
a = 300.0
b = 0.513
delta_theta = 37.0
arm_offsets = [35.0, 155.0, 275.0]
num_super_stations_arms = num_arms * core_arm_count
ss_arm_petal_angle = -360.0 * random(num_super_stations_arms) + 360.0
# Outer arms (same outer 3 * 12 = 36 stations as v4a)
outer_arm_count = 12 # Number of super-stations per outer arm
num_super_stations_outer = num_arms * outer_arm_count
v4a_ss_enu_file = 'v7ska1lowN1v2rev3R.enu.94x4.fixed.txt'
ss_petal_angle_outer = -360.0 * random(num_super_stations_outer) + 360.0
# Stations
num_stations_per_ss = 6
out_dir = 'v4d_layout'
if not os.path.isdir(out_dir):
os.makedirs(out_dir)
# ==========================================================================
# == Super-stations
# Generate core ring super-stations
v4d_ss_x_rings = numpy.zeros(num_super_stations_rings)
v4d_ss_y_rings = numpy.zeros(num_super_stations_rings)
idx = 0
for i, hist in enumerate(ring_counts):
angles = numpy.arange(hist) * (360.0 / hist)
angles += ring_start_angle[i]
x = ring_radii[i] * numpy.cos(numpy.radians(angles))
y = ring_radii[i] * numpy.sin(numpy.radians(angles))
v4d_ss_x_rings[idx:idx+hist] = x
v4d_ss_y_rings[idx:idx+hist] = y
idx += hist
# Generate core spiral arm super-stations
v4d_ss_x_arms = numpy.zeros(num_super_stations_arms)
v4d_ss_y_arms = numpy.zeros(num_super_stations_arms)
for i in range(num_arms):
t = numpy.arange(1, core_arm_count + 1) * delta_theta
t = numpy.radians(t)
x = a * numpy.exp(b * t) * numpy.cos(t + numpy.radians(arm_offsets[i]))
y = a * numpy.exp(b * t) * numpy.sin(t + numpy.radians(arm_offsets[i]))
i0 = i * core_arm_count
i1 = i0 + core_arm_count
v4d_ss_x_arms[i0:i1] = x
v4d_ss_y_arms[i0:i1] = y
# Load super-station outer spiral arms from the v4a config
v4a_ss_enu = numpy.loadtxt(v4a_ss_enu_file)
v4a_ss_enu = v4a_ss_enu[:, 1:]
v4a_ss_r = (v4a_ss_enu[:, 0]**2 + v4a_ss_enu[:, 1]**2)**0.5
sort_idx = numpy.argsort(v4a_ss_r)
v4a_ss_enu = v4a_ss_enu[sort_idx[::-1], :]
v4d_ss_x_outer = v4a_ss_enu[:num_super_stations_outer, 0]
v4d_ss_y_outer = v4a_ss_enu[:num_super_stations_outer, 1]
# == Stations
# Generate core ring stations
v4d_st_x_rings = numpy.zeros((num_super_stations_rings,
num_stations_per_ss))
v4d_st_y_rings = numpy.zeros_like(v4d_st_x_rings)
for i in range(num_super_stations_rings):
angles = 360.0 / (num_stations_per_ss - 1) * \
numpy.arange(num_stations_per_ss - 1)
x = (st_radius * 2.0) * numpy.cos(numpy.radians(angles))
y = (st_radius * 2.0) * numpy.sin(numpy.radians(angles))
x, y = rotate_coords(x, y, ss_ring_petal_angle[i])
v4d_st_x_rings[i, 1:] = x
v4d_st_y_rings[i, 1:] = y
v4d_st_x_rings[i, :] += v4d_ss_x_rings[i]
v4d_st_y_rings[i, :] += v4d_ss_y_rings[i]
v4d_st_x_rings = v4d_st_x_rings.flatten()
v4d_st_y_rings = v4d_st_y_rings.flatten()
# Generate core spiral arm stations
v4d_st_x_arms = numpy.zeros((num_super_stations_arms,
num_stations_per_ss))
v4d_st_y_arms = numpy.zeros_like(v4d_st_x_arms)
for i in range(num_super_stations_arms):
angles = 360.0 / (num_stations_per_ss - 1) * \
numpy.arange(num_stations_per_ss - 1)
x = (st_radius * 2.0) * numpy.cos(numpy.radians(angles))
y = (st_radius * 2.0) * numpy.sin(numpy.radians(angles))
x, y = rotate_coords(x, y, ss_arm_petal_angle[i])
v4d_st_x_arms[i, 1:] = x
v4d_st_y_arms[i, 1:] = y
v4d_st_x_arms[i, :] += v4d_ss_x_arms[i]
v4d_st_y_arms[i, :] += v4d_ss_y_arms[i]
v4d_st_x_arms = v4d_st_x_arms.flatten()
v4d_st_y_arms = v4d_st_y_arms.flatten()
# Generate outer arm stations
v4d_st_x_outer = numpy.zeros((num_super_stations_outer, num_stations_per_ss))
v4d_st_y_outer = numpy.zeros((num_super_stations_outer, num_stations_per_ss))
for i in range(num_super_stations_outer):
angles = 360.0 / (num_stations_per_ss - 1) * \
numpy.arange(num_stations_per_ss - 1)
x = (st_radius * 2.0) * numpy.cos(numpy.radians(angles))
y = (st_radius * 2.0) * numpy.sin(numpy.radians(angles))
x, y = rotate_coords(x, y, ss_petal_angle_outer[i])
v4d_st_x_outer[i, 1:] = x
v4d_st_y_outer[i, 1:] = y
v4d_st_x_outer[i, :] += v4d_ss_x_outer[i]
v4d_st_y_outer[i, :] += v4d_ss_y_outer[i]
v4d_st_x_outer = v4d_st_x_outer.flatten()
v4d_st_y_outer = v4d_st_y_outer.flatten()
# Concatenate coords.
v4d_ss_x = numpy.hstack((v4d_ss_x_rings, v4d_ss_x_arms, v4d_ss_x_outer))
v4d_ss_y = numpy.hstack((v4d_ss_y_rings, v4d_ss_y_arms, v4d_ss_y_outer))
v4d_st_x = numpy.hstack((v4d_st_x_rings, v4d_st_x_arms, v4d_st_x_outer))
v4d_st_y = numpy.hstack((v4d_st_y_rings, v4d_st_y_arms, v4d_st_y_outer))
# === Generate layouts ==============================
num_stations = v4d_st_x.shape[0]
v4d_st_enu = numpy.zeros((num_stations, 3))
v4d_st_enu[:, 0] = v4d_st_x
v4d_st_enu[:, 1] = v4d_st_y
numpy.savetxt(join(out_dir, 'v4d_stations_enu.txt'), v4d_st_enu,
fmt='% -16.12f % -16.12f % -16.12f')
num_super_stations = v4d_ss_x.shape[0]
v4d_ss_enu = numpy.zeros((num_super_stations, 3))
v4d_ss_enu[:, 0] = v4d_ss_x
v4d_ss_enu[:, 1] = v4d_ss_y
numpy.savetxt(join(out_dir, 'v4d_super_stations_enu.txt'), v4d_ss_enu,
fmt='% -16.12f % -16.12f % -16.12f')
# ==== Plotting ===========================================================
fig = pyplot.figure(figsize=(8, 8))
ax = fig.add_subplot(111, aspect='equal')
for i in range(num_super_stations_rings):
circle = pyplot.Circle((v4d_ss_x_rings[i], v4d_ss_y_rings[i]),
ss_radius, color='b', fill=True, alpha=0.5,
linewidth=0.0)
ax.add_artist(circle)
arm_colors = ['y', 'g', 'r']
for i in range(num_super_stations_arms):
q = int(i / core_arm_count)
circle = pyplot.Circle((v4d_ss_x_arms[i], v4d_ss_y_arms[i]),
ss_radius, color=arm_colors[q],
fill=True, alpha=0.5, linewidth=0.0)
ax.add_artist(circle)
for q in range(num_arms):
i0 = q * outer_arm_count
i1 = i0 + outer_arm_count
for i in range(i0, i1):
circle = pyplot.Circle((v4d_ss_x_outer[i], v4d_ss_y_outer[i]),
ss_radius, color='c', fill=True, alpha=0.5)
ax.add_artist(circle)
# Plot station positions
for i in range(v4d_st_x.shape[0]):
circle = pyplot.Circle((v4d_st_x[i], v4d_st_y[i]),
st_radius, color='k', linewidth=1.0,
fill=True, alpha=0.2)
ax.add_artist(circle)
# circle = pyplot.Circle((0.0, 0.0), 1700.0, color='r', linestyle='--',
# linewidth=1.0, fill=False, alpha=0.5)
# ax.add_artist(circle)
ax.grid(which='both')
ax.grid(which='minor', alpha=0.5)
ax.grid(which='major', alpha=1.0)
ax.set_ylabel('North [m]')
ax.set_xlabel('East [m]')
ax.set_xlim(-1500, 1500)
ax.set_ylim(-1500, 1500)
pyplot.savefig(join(out_dir, 'v4d_station_layout_zoom_1.5km.png'))
ax.set_xlim(-3000, 3000)
ax.set_ylim(-3000, 3000)
pyplot.savefig(join(out_dir, 'v4d_station_layout_zoom_3.0km.png'))
ax.set_xlim(-5000, 5000)
ax.set_ylim(-5000, 5000)
pyplot.savefig(join(out_dir, 'v4d_station_layout_zoom_5.0km.png'))
ax.set_xlim(-50000, 50000)
ax.set_ylim(-50000, 50000)
pyplot.savefig(join(out_dir, 'v4d_station_layout_50.0km.png'))
pyplot.close(fig)
if uvwsim_found:
# TODO-BM make this a function in layout_utils.py
print('generating uv coords...')
x = v4d_st_x
y = v4d_st_y
num_stations = x.shape[0]
z = numpy.zeros_like(x)
lon = radians(116.63128900)
lat = radians(-26.69702400)
alt = 0.0
ra = radians(68.698903779331502)
dec = radians(-26.568851215532160)
mjd_mid = 57443.4375000000
obs_length = 4.0 * 3600.0 # seconds
num_times = int(obs_length / (3 * 60.0))
# print('num_times =', num_times)
dt_s = obs_length / float(num_times)
mjd_start = mjd_mid - (obs_length / 2.0) / (3600.0 * 24.0)
mjd_start = mjd_mid
obs_length = 0.0
dt_s = 0.0
num_times = 1
num_baselines = num_stations * (num_stations - 1) / 2
x, y, z = convert_enu_to_ecef(x, y, z, lon, lat, alt)
uu, vv, ww = generate_baseline_uvw(x, y, z, ra, dec, num_times,
num_baselines, mjd_start,
dt_s)
layout_utils.plot_hist(uu, vv, join(out_dir, 'v4d_hist.png'),
'v4d snapshot-uv')
layout_utils.plot_uv_dist(uu, vv, st_radius,
join(out_dir, 'v4d_snapshot_uv_zenith'))
layout_utils.plot_uv_grid_image(uu, vv, 5.0,
join(out_dir, 'uv_image'))
def main():
"""
1. Generate a large-ish core of stations using random generator.
a. overlap some stations in the core to have a very dense station
region
2. After core area start using arms but generate some randomness in the arms
by placing antennas randomly near the outer stations keeping them along
the spiral
3. Remove radius redundancy in the spiral arms
"""
# =========================================================================
# ====== Core
seed = 1
num_tries = 10
num_core_stations = (1 + 5 + 11 + 17) * 6 + (3 * 6)
core_radius_m = 480.0
inner_core_radius_m = 280.0
station_radius_m = 35.0 / 2.0
sll = -28
# ====== Core arms
num_arms = 3
core_arm_count = 4
stations_per_arm_cluster = 6
arm_cluster_radius = 75.0
# a = 300.0
# b = 0.513
a = 300.0
b = 0.513
delta_theta = math.radians(37.0)
arm_offsets = numpy.radians([35.0, 155.0, 270.0])
a2 = 500.0
b2 = 0.513
delta_theta2 = math.radians(12.0)
arm_offsets2 = numpy.radians([35.0, 155.0, 270.0])
num_core_arm_stations = num_arms * core_arm_count * stations_per_arm_cluster
# ====== Outer arms
outer_arm_count = 12
stations_per_outer_cluster = 6
num_clusters_outer = outer_arm_count * num_arms
v4a_ss_enu_file = 'v7ska1lowN1v2rev3R.enu.94x4.fixed.txt'
outer_arm_cluster_radius = 80.0
# ===== uvw coordinate generation.
lon = radians(116.63128900)
lat = radians(-26.69702400)
alt = 0.0
ra = radians(68.698903779331502)
dec = radians(-26.568851215532160)
mjd_mid = 57443.4375000000
# obs_length = 0.0
# mjd_start = mjd_mid
# dt_s = 0.0
# num_times = 1
obs_length = 2.0 * 3600.0 # seconds
num_times = int(obs_length / (3.0 * 60.0))
dt_s = obs_length / float(num_times)
mjd_start = mjd_mid - ((obs_length / 2.0) / 3600.0 * 24.0)
print('num times = %i' % num_times)
out_dir = 'v5d-2h'
# =========================================================================
if not os.path.isdir(out_dir):
os.makedirs(out_dir)
# Generate core stations
x_core, y_core, weights, r_weights = \
generate_random_core(num_core_stations, core_radius_m,
inner_core_radius_m, sll, station_radius_m,
num_tries, seed)
# Core arms
x_arm, y_arm, cx_arm, cy_arm = \
generate_core_arms(num_arms, core_arm_count, stations_per_arm_cluster,
arm_cluster_radius, station_radius_m,
a, b, delta_theta, arm_offsets, num_tries)
# Core arms
x_arm_2, y_arm_2, cx_arm_2, cy_arm_2 = \
generate_core_arms_2(num_arms, core_arm_count, stations_per_arm_cluster,
arm_cluster_radius, station_radius_m,
a2, b2, delta_theta2, arm_offsets2, num_tries)
# Outer stations.
x_arm_outer, y_arm_outer, cx_outer, cy_outer = \
generate_outer_arms(v4a_ss_enu_file, num_clusters_outer,
stations_per_outer_cluster,
outer_arm_cluster_radius, station_radius_m,
num_tries)
# Plotting
plot_layout(x_core, y_core,
x_arm, y_arm, x_arm_2, y_arm_2,
x_arm_outer, y_arm_outer,
cx_arm, cy_arm, cx_arm_2, cy_arm_2,
cx_outer, cy_outer, station_radius_m,
inner_core_radius_m, core_radius_m, arm_cluster_radius,
outer_arm_cluster_radius, out_dir)
plot_core_thinning_profile(r_weights, weights, core_radius_m,
inner_core_radius_m, out_dir)
if uvwsim_found:
x = numpy.hstack((x_core, x_arm_2, x_arm_outer))
y = numpy.hstack((y_core, y_arm_2, y_arm_outer))
print('total stations = %i' % x.shape[0])
num_stations = x.shape[0]
z = numpy.zeros_like(x)
num_baselines = num_stations * (num_stations - 1) / 2
x, y, z = convert_enu_to_ecef(x, y, z, lon, lat, alt)
uu, vv, ww = generate_baseline_uvw(x, y, z, ra, dec, num_times,
num_baselines, mjd_start,
dt_s)
plot_hist(uu, vv, join(out_dir, 'uv_hist_%.2fh.png'
% (obs_length/3600.0)),
'v5d %.2f h' % (obs_length/3600.0))
plot_uv_dist(uu, vv, station_radius_m, join(out_dir, 'uv_%.2fh'
% (obs_length/3600.0)))
plot_uv_grid_image(uu, vv, 5.0, join(out_dir, 'uv_image'))
# TODO-BM see ALMA memo for plots?
# TODO-BM Plot of azimuthal variation
# TODO-BM movie of uv coverage histogram improvement with time?
# TODO-BM convolve uv response with station beam?!
print('making image...')
imager = Imager('single')
fov = 1.0
im_size = 2048
freq = 150.0e6
wavelength = 299792458.0 / freq
uu /= wavelength
vv /= wavelength
ww /= wavelength
amp = numpy.ones(uu.shape, dtype='c16')
weight = numpy.ones(uu.shape, dtype='f8')
image = imager.make_image(uu, vv, ww, amp, weight, fov, im_size)
fig = pyplot.figure(figsize=(8, 8))
ax = fig.add_subplot(111, aspect='equal')
ax.imshow(image, interpolation='nearest')
pyplot.show()
cell = math.degrees(imager.fov_to_cellsize(math.radians(fov), im_size))
save_fits_image_2(join(out_dir, 'psf.fits'), image, cell, math.degrees(ra),
math.degrees(dec), freq)