Major refactor to ease duplicate computations and plotting

This commit is contained in:
Luke 2018-07-20 19:07:01 -07:00
parent d6d75b804f
commit 539c2f7481
4 changed files with 326 additions and 120 deletions

View file

@ -10,25 +10,6 @@ sys.path.append("./pySmithPlot")
import smithplot
from smithplot import SmithAxes
################################################################################
# Define my helper functions.
def dB20(volt_tf):
"""Describe signal gain of a transfer function in dB (i.e. 20log(x))"""
return 20*np.log10(np.abs(volt_tf))
def ang(volt_tf):
"""Describe phase of a transfer function in degrees. Not unwrapped."""
return 180/np.pi*np.angle(volt_tf)
def ang_unwrap(volt_tf):
"""Describe phase of a transfer function in degrees. With unwrapping."""
return 180/np.pi*np.unwrap(np.angle(volt_tf))
def dB10(pwr_tf):
"""Describe power gain of a transfer function in dB (i.e. 10log(x))"""
return 10*np.log10(np.abs(pwr_tf))
def atan(x):
return 180/np.pi*np.arctan(x)
################################################################################
# Override the defaults for this script
rcParams['figure.figsize'] = [10,7]
@ -36,76 +17,57 @@ default_window_position=['+20+80', '+120+80']
################################################################################
# Operating Enviornment (i.e. circuit parameters)
from TankGlobals import *
import TankGlobals
from FreqClass import FreqClass
from tankComputers import *
S=TankGlobals.ampSystem()
f=FreqClass(501, S.f0, S.bw_plt)
################################################################################
# Now generate the sweep of resonance tuning (gamma, and capacitance)
# Linear based gamma spacing
#gamma_swp = np.linspace(-gamma,gamma,gamma_sweep_steps)
# Linear PHASE gamma spacing
# First compute the most extreme phase given the extreme gamma
g1_limit = np.sqrt( g1*g1 - (gamma*gamma) * c1/l1 )
K_limit = np.sqrt(c1/l1)*1/g1_limit
phase_limit = np.mod(np.pi/2 - np.arctan( -1/K_limit * 1/gamma ),np.pi) - np.pi
if abs(phase_limit) < phase_limit_requested:
print("==> WARN: Phase Beyond bounds, leaving at limits. <==")
print("==> %.3f requested, but hardware limit is %.3f <==" % \
(180/np.pi*phase_limit_requested, 180/np.pi*abs(phase_limit)))
sys.exit(-1)
else:
phase_limit = phase_limit_requested
# This gives us our equal phase spacing points
phase_swp = np.linspace(-1,1,gamma_sweep_steps) * phase_limit
# Then use this to compute the gamma steps to produce arbitrary phase given
# our perfect gain constraint.
gamma_swp = np.sign(phase_swp)/np.sqrt(np.power(np.tan(np.pi/2 - phase_swp),2)+1) * g1 / np.sqrt(c1/l1)
# We want a smooth transition out to alpha. So For now assume a squares
# weighting out to the maximum alpha at the edges.
gain_variation = -8*0 # dB
S.alpha_min = dB2Vlt(gain_variation)
# compute correction factor for g1 that will produce common gain at f0
g1_swp = np.sqrt( g1*g1 - (gamma_swp*gamma_swp) * c1/l1 )
# this is defined as the class default
g1_swp = S.g1_swp
# and compute how much of a negative gm this requres, and it's relative
# proportion to the gm of the assumed main amplifier gm.
g1_boost = (g1_swp - g1)
g1_ratio = -g1_boost / gm1
g1_boost = (g1_swp - S.g1)
g1_ratio = -g1_boost / S.gm1
c1_swp = c1 * (1 + gamma_swp)
## Report System Descrption
print(' L1 = %.3fpH, C1 = %.3ffF' % (1e3*l1, 1e6*c1))
print(' Rp = %.3f Ohm' % (1/g1))
print(' Max G1 boost %.2fmS (%.1f%% of gm1)' % \
(1e3*np.max(np.abs(g1_boost)), 100*np.max(g1_ratio)))
y_tank = np.zeros((len(gamma_swp),len(f)), dtype=complex)
tf = np.zeros((len(gamma_swp),len(f)), dtype=complex)
for itune,gamma_tune in enumerate(gamma_swp):
c1_tune = c1_swp[itune]
g1_tune = g1_swp[itune]
K = np.sqrt(c1/l1)/g1_tune
y_tank_tmp = g1_tune + jw*c1_tune + 1/(jw * l1)
y_tank[itune,:] = y_tank_tmp
tf_tmp = gm1 / g1_tune * \
1j*(1+delta) / \
( 1j*(1+delta) + K*(1 - (1+gamma_tune)*np.power(1+delta,2)) )
tf[itune,:] = tf_tmp
tf = tf.T
################################################################################
# Generate a reference implementation
(y_tank, tf) = S.compute_block(f)
(_, tf_ref) = S.compute_ref(f)
# double to describe with perfect inversion stage
tf = np.column_stack((tf,-tf))
ref_index = int(gamma_swp.shape[0]/2)
tf_r = tf / (tf[:,ref_index]*np.ones((tf.shape[1],1))).T
y_tank = y_tank.T
# compute the relative transfer function thus giving us flat phase, and
# flat (ideally) gain response if our system perfectly matches the reference
tf_r = tf / (tf_ref*np.ones((tf.shape[1],1))).T
# We will also do a direct angle comparison
tf_r_ang_ideal = wrap_rads(np.concatenate((-S.phase_swp, -np.pi - S.phase_swp)))
tf_r_ang = np.angle(tf_r)
tf_r_ang_rms = np.sqrt(np.mean(np.power(tf_r_ang-tf_r_ang_ideal,2),0))
y_tank = y_tank.T
################################################################################
# Compute RMS phase error relative to ideal reference across plotting bandwidth
(bw_ang, rms_ang_swp)=rms_v_bw(tf_r_ang-tf_r_ang_ideal, S.bw_plt)
(bw_mag, rms_gain_swp)=rms_v_bw(tf_r, S.bw_plt)
print(ang(tf[f==28,:]))
################################################################################
h1 = pp.figure()
h2 = pp.figure(figsize=(5,7))
h3 = pp.figure(figsize=(5,7))
mgr = pp.get_current_fig_manager()
################################################################################
ax1 = h1.add_subplot(2,2,1, projection='smith')
@ -115,14 +77,19 @@ ax4 = h1.add_subplot(2,2,4)
ax1.plot(y_tank, datatype=SmithAxes.Y_PARAMETER, marker="None")
ax2.plot(np.angle(tf), dB20(tf))
ax3.plot(f,dB20(tf))
ax4.plot(f,ang_unwrap(tf))
ax3.plot(f.hz,dB20(tf))
ax4.plot(f.hz,ang_unwrap(tf))
################################################################################
ax8 = h2.add_subplot(2,1,1)
ax9 = h2.add_subplot(2,1,2)
ax8.plot(f,dB20(tf_r))
ax9.plot(f,ang_unwrap(tf_r.T).T)
ax6 = h2.add_subplot(2,1,1)
ax7 = h2.add_subplot(2,1,2)
ax6.plot(f.hz,dB20(tf_r))
ax7.plot(f.hz,ang_unwrap(tf_r.T).T)
ax8 = h3.add_subplot(2,1,1)
ax9 = h3.add_subplot(2,1,2)
ax8.plot(bw_mag,dB20(rms_gain_swp))
ax9.plot(bw_ang,rms_ang_swp*180/np.pi)
ax1.set_title('Tank Impedance')
ax2.set_title('Transfer Function')
@ -131,20 +98,31 @@ ax3.set_title('TF Gain')
ax3.set_ylabel('Gain (dB)')
ax4.set_title('TF Phase')
ax4.set_ylabel('Phase (deg)')
ax8.set_title('TF Relative Gain')
ax8.set_ylabel('Relative Gain (dB)')
ax9.set_title('TF Relative Phase')
ax9.set_ylabel('Relative Phase (deg)')
for ax_T in [ax3, ax4, ax8, ax9]:
ax6.set_title('TF Relative Gain')
ax6.set_ylabel('Relative Gain (dB)')
ax7.set_title('TF Relative Phase')
ax7.set_ylabel('Relative Phase (deg)')
for ax_T in [ax3, ax4, ax6, ax7]:
ax_T.grid()
ax_T.set_xlabel('Freq (GHz)')
ax_T.set_xlim(( np.min(f), np.max(f) ))
ax_T.set_xlim(f.hz_range)
ax8.set_title('RMS Gain Error')
ax8.set_ylabel('RMS Gain Error (dB)')
ax9.set_title('RMS Phase Error')
ax9.set_ylabel('RMS Phase Error (deg)')
for ax_T in [ax8, ax9]:
ax_T.grid()
ax_T.set_xlim((0,S.bw_plt))
ax_T.set_xlabel('Bandwidth (GHz)')
################################################################################
h1.tight_layout()
h2.tight_layout()
h3.tight_layout()
mgr.window.geometry(default_window_position[0])
h1.show()
mgr.window.geometry(default_window_position[1])
h2.show()
h3.show()