# -*- coding: utf-8 -*-
"""
Created on Sat Jan 31 14:07:10 2015

@author: mespence
"""

from numpy import linspace, argmin
from pylab import plot, xlabel, ylabel, grid, title

VNP    = 10e-6
vnn    = 1e-6
SNR    = 4
Delta0 = 100e-6
Econv0 = 50e-12
Pamp0  = 1e-6
fs     = 20e3

k = 1.38e-23
T = 310.5
C = 10e-9
gamma = 2/3.0


a = 1-VNP**2/vnn**2/8/SNR
b = gamma*k*T/C/vnn**2
c1 = k*T/C/vnn**2
c2 = Delta0**2/vnn**2/12
print -b/a/2, b**2/a**2/4 -c1/a, -c2/a


def A(B):
    return -b/a/2 + (b**2/a**2/4 -c1/a -c2/a/B**2)**0.5

B = linspace(0.05,4,2000)
Ptot = Pamp0*A(B)+fs*Econv0*B**3
Bopt = B[argmin(Ptot)]
Avopt = A(Bopt)
LSBopt = Delta0/Bopt
Vswopt = VNP*Avopt
print Bopt, Avopt, LSBopt, Vswopt, Vswopt/LSBopt

plot(B,1e6*Ptot)
xlabel("B")
ylabel("Total Power [uW]")
grid('on')
title('Total Power vs. LSB Scaling Factor')