#!/usr/bin/python
import math, sys
from measure import parse_length, parse_freq
#for 50% efficency
k = 0.5
def dish_gain(wlen, diam):
tmp = math.pi * diam / wlen
return 10 * math.log10(tmp * tmp * k)
if (len(sys.argv) != 3):
print "Usage:\n{} <freq> <diam>".format(sys.argv[0])
else:
freq, wlen_in, wlen_m = parse_freq(sys.argv[1], 'frequency')
diam_in, diam_m = parse_length(sys.argv[2], 'diameter')
gain = dish_gain(wlen_m, diam_m)
print "gain: {:f} dB (assuming 50% efficency)\n".format(gain)
#!/usr/bin/python
import math, sys
from measure import parse_length, parse_freq
def loss(wlen, dist):
k = math.pi * 4
tmp = k * dist / wlen
return 20 * math.log10(tmp)
def freq_to_wlen(freq):
return light_speed / freq
if (len(sys.argv) != 3):
print "Usage:\n{} <freq> <distance>".format(sys.argv[0])
else:
dist_in, dist_m = parse_length(sys.argv[2])
freq_hz, wlen_in, wlen_m = parse_freq(sys.argv[1])
atten = loss(wlen_m, dist_m)
print "atten: {:f} dB\n".format(atten)
