/// <summary>
/// Initializes a new instance of the <see cref="Noise"/> class.
/// </summary>
/// <param name="context">The context.</param>
/// <exception cref="ArgumentNullException">Thrown if <paramref name="context"/> is <c>null</c>.</exception>
public Noise(IComponentBindingContext context)
: base(context)
{
_state = context.GetState <INoiseSimulationState>();
_rs = new NoiseThermal("rs", ComplexVariables.Positive, ComplexVariables.PosPrime);
_id = new NoiseShot("id", ComplexVariables.PosPrime, ComplexVariables.Negative);
_flicker = new NoiseGain("flicker", ComplexVariables.PosPrime, ComplexVariables.Negative);
}
/// <summary>
/// Initializes a new instance of the <see cref="Noise"/> class.
/// </summary>
/// <param name="context">The binding context.</param>
/// <exception cref="ArgumentNullException">Thrown if <paramref name="context"/> is <c>null</c>.</exception>
public Noise(IComponentBindingContext context)
: base(context)
{
_state = context.GetState <INoiseSimulationState>();
_properties = context.ModelBehaviors.GetValue <ModelTemperature>().Properties;
var d = Variables.Drain;
var s = Variables.Source;
var dp = Variables.DrainPrime;
var sp = Variables.SourcePrime;
_rd = new NoiseThermal("rd", d, dp);
_rs = new NoiseThermal("rs", s, sp);
_id = new NoiseThermal("id", dp, sp);
_flicker = new NoiseGain("flicker", dp, sp);
}
/// <summary>
/// Integrates the noise density into the total integrated noise figures.
/// It computes the integration assuming that noise = a * frequency^exponent. It
/// automatically tracks the noise density from one point to the next.
/// </summary>
/// <param name="state">The noise simulation state.</param>
/// <exception cref="ArgumentNullException">Thrown if <paramref name="state"/> is <c>null</c>.</exception>
/// <exception cref="ArgumentException">Thrown if the simulation state does not store enough points in history.</exception>
public virtual void Integrate(INoiseSimulationState state)
{
state.ThrowIfNull(nameof(state));
var lnOutputNoiseDensity = Math.Log(Math.Max(OutputNoiseDensity, 1e-38));
var lnFrequency = state.Point.Value.LogFrequency;
var lnLastFrequency = state.Point.GetPreviousValue(1).LogFrequency;
var exponent = (lnOutputNoiseDensity - _lnLastOutputNoiseDensity) / (lnFrequency - lnLastFrequency);
double delta;
// Use simple box integration if the noise contribution doesn't change significantly over the frequency
if (Math.Abs(exponent) < 1e-10)
{
delta = state.Point.Value.Frequency - state.Point.GetPreviousValue(1).Frequency;
TotalOutputNoise += OutputNoiseDensity * delta;
TotalInputNoise += OutputNoiseDensity * state.Point.Value.InverseGainSquared * delta;
return;
}
exponent += 1.0;
// Is the noise ~ 1/f?
if (Math.Abs(exponent) < 1e-10)
{
delta = lnFrequency - lnLastFrequency;
}
else
{
delta = (Math.Exp(exponent * lnFrequency) - Math.Exp(exponent * lnLastFrequency)) / exponent;
}
// Compute total output noise
var a = Math.Exp(lnOutputNoiseDensity - exponent * lnFrequency);
TotalOutputNoise += a * delta;
// Compute total input noise
a = Math.Exp(lnOutputNoiseDensity + state.Point.Value.LogInverseGainSquared - exponent * lnFrequency);
TotalInputNoise += a * (lnFrequency - lnLastFrequency);
_lnLastOutputNoiseDensity = lnOutputNoiseDensity;
}
/// <summary>
/// Initializes a new instance of the <see cref="Noise"/> class.
/// </summary>
/// <param name="context">The context.</param>
/// <exception cref="ArgumentNullException">Thrown if <paramref name="context"/> is <c>null</c>.</exception>
public Noise(IComponentBindingContext context)
: base(context)
{
var complex = context.GetState <IComplexSimulationState>();
_noise = context.GetState <INoiseSimulationState>();
var c = complex.GetSharedVariable(context.Nodes[0]);
var b = complex.GetSharedVariable(context.Nodes[1]);
var e = complex.GetSharedVariable(context.Nodes[2]);
var bp = BasePrime;
var cp = CollectorPrime;
var ep = EmitterPrime;
_rc = new NoiseThermal("rc", c, cp);
_rb = new NoiseThermal("rb", b, bp);
_re = new NoiseThermal("re", e, ep);
_ic = new NoiseShot("ic", cp, ep);
_ib = new NoiseShot("ib", bp, ep);
_flicker = new NoiseGain("1/f", bp, ep);
}
/// <summary>
/// Initializes a new instance of the <see cref="NoiseSimulationState"/> class.
/// </summary>
/// <param name="parent">The parent.</param>
/// <exception cref="ArgumentNullException">Thrown if <paramref name="parent"/> is <c>null</c>.</exception>
public NoiseSimulationState(INoiseSimulationState parent)
{
_parent = parent.ThrowIfNull(nameof(parent));
}