Source code for pmrf.models.components.ideal

"""
Ideal models, such as ports, grounds and transformers.
"""
import jax.numpy as jnp
from pmrf.frequency import Frequency
from pmrf.models.model import Model
from pmrf.models.components.lumped import MATCH, SHORT



class Port(Model):
    """
    Represents a circuit port.

    This class serves as a placeholder or marker for external connections in a circuit definition.
    Calling an instance returns a matched load model.
    """
    def __call__(self) -> Model:
        """
        Return the equivalent model for a terminated port.

        Returns
        -------
        Model
            A matched load (`MATCH`).
        """
        return MATCH

    


class Ground(Model):
    """
    Represents a ground connection.

    This class serves as a placeholder for a ground node in a circuit definition.
    Calling an instance returns a short circuit model.
    """
    def __call__(self) -> Model:
        return SHORT




class Transformer(Model):
    """
    An ideal, lossless, frequency-independent 4-port 1:1 transformer.

    The S-parameters are constant across all frequencies.
    """


    def s(self, freq: Frequency) -> jnp.ndarray:
        s = 0.5 * jnp.ones((freq.npoints, 4, 4), dtype='complex')
        s = s.at[:, 0, 3].set(-0.5)
        s = s.at[:, 1, 2].set(-0.5)
        s = s.at[:, 2, 1].set(-0.5)
        s = s.at[:, 3, 0].set(-0.5)

        return s


    


class SourceConverter(Model):
    """
    An ideal 3-port source converter.

    This model represents a specific ideal component with a fixed, frequency-independent
    3x3 scattering matrix.
    """


    def s(self, freq: Frequency) -> jnp.ndarray:
        s_one = jnp.array([
            [ 1,  2, -2],
            [ 2,  1,  2],
            [-2,  2,  1]
        ], dtype='complex')
        s_one /= 3.0

        s = jnp.tile(s_one, (freq.npoints, 1, 1))        
        return s