added "Filter" Component

README.md

@@ -7,3 +7,8 @@ The current Documentation is found under this link : <https://rf-linkbudget.read
 ## Abstract
 RF-LinkBudget is a software package to aid RF Hardware Developer in defining and comparing LinkBudget’s of RF Ciruits.
 It calculates key parameter’s like cumulative Noise Figure, cumulates Gain, Intermodulation Signal Amplitudes and so on.
+
+## Changelog
+
+# 1.0.2
+Added `Filter` Component

docs/rf_linkbudget_circuit.rst

@@ -292,6 +292,23 @@ As we see in this example, we set the attenuator to 15.6dB for all input powers
 The function **setAttenuation** will set it to the nearest attenuation value defined in the constructor.
 In this case the zero value will get set to effectively 1.0dB and the 15.6dB will be rounded up to 16.0dB.
 
+
+Filter
+^^^^^^^^^^^^^^
+
+An filter is a classical two port device.
+It has a frequency response
+
+.. code-block:: python
+    :linenos:
+
+    filter = rf.Filter("Filter 1",
+                          Att=[(100, 1.5),(200, 4.5),(300, 55)])
+
+
+As we see, we can define the frequency response like the frequency response of an Amplifier.
+
+
 SPDT
 ^^^^^^^^^^^^^^
 

rf_linkbudget/__init__.py

@@ -11,6 +11,7 @@
 
 from .circuit import Amplifier
 from .circuit import Attenuator
+from .circuit import Filter
 from .circuit import SPDT
 from .circuit import Mixer
 #from .circuit import ADC

rf_linkbudget/circuit.py

@@ -530,7 +530,7 @@ class genericTwoPort(AbstractDevice):
         device name
     Gain : list of [f, Gain]
         Gain representation in [dB], frequency in [Hz]
-    Tn : list of [Tn @ Port 1, Tn @ Port 2]
+    Tn : list of [Tn @ Port 1, Tn @ Port 2] : Tn np.float or list of [f, Tn]
         noisetemperature of object, represented at the "target" port [°K]
     P1 : list of [P1 @ Port 1, P1 @ Port 2]
         Signal Compression Point of object, represented at the "target" port in [dB]
@@ -593,7 +593,7 @@ def fromSParamFile(cls, name, filename, Tn, P1, IP3, patchString='S12DB'):
         sparam = rf.touchstone.Touchstone(filename)
         sparam = sparam.get_sparameter_data(format='db')
 
-        Gain = [[f, [s21]] for f, s21 in zip(sparam['frequency'], sparam[patchString])]
+        Gain = [(f, s21) for f, s21 in zip(sparam['frequency'], sparam[patchString])]
 
         return cls(name, Gain=Gain, Tn=Tn, P1=P1, IP3=IP3)
 
@@ -627,18 +627,48 @@ def calcCurrentEdge(self, start, end, data):
 
         if start == self.ports[0] and end == self.ports[1]:
 
-            Gain = np.interp(data['f'], *zip(*self.Gain))                 # interpolate Gain value
+            # Gain = np.interp(data['f'], *zip(*self.Gain))                 # interpolate Gain value
+            Gain = self.interpolateIfListOfFreqValTuple(data['f'], self.Gain)
+            Tn = self.interpolateIfListOfFreqValTuple(data['f'], self.Tn[1])
+            P1 = self.interpolateIfListOfFreqValTuple(data['f'], self.P1[1])
+            IP3 = self.interpolateIfListOfFreqValTuple(data['f'], self.IP3[1])
+
             out['Gain'] = data['Gain'] + Gain                             # calc cumulative Gain
-            out['Tn'] = RFMath.calc_Tn(data['Tn'], self.Tn[1], Gain)      # calc output NoiseTemperature
+            out['Tn'] = RFMath.calc_Tn(data['Tn'], Tn, Gain)              # calc output NoiseTemperature
             out['p'] = RFMath.calc_Pout(data['p'], Gain)                  # calc output signal power
-            out['P1'] = RFMath.calc_P1(data['P1'], self.P1[1], Gain)      # calc output P1dB point
-            out['IP3'] = RFMath.calc_IP3(data['IP3'], self.IP3[1], Gain)  # calc output IP3 point (simple)
+            out['P1'] = RFMath.calc_P1(data['P1'], P1, Gain)              # calc output P1dB point
+            out['IP3'] = RFMath.calc_IP3(data['IP3'], IP3, Gain)          # calc output IP3 point (simple)
             # calc other values...
             return out
 
         else:
             raise ValueError('this should not happen')
 
+    def interpolateIfListOfFreqValTuple(self, freq, value):
+        """
+        if value is of the form: [(f,val)] then interpolate, otherwise ignore this function
+
+        Parameters
+        ----------
+        freq : np.float
+            frequency of interest
+        value : float, or [(f,val)]
+            value which might get interpolated
+
+        Returns
+        -------
+        data : np.float
+            value or interpolated value
+        """
+
+        if type(value) != list:
+            return value
+        if len(value) == 0:
+            raise ValueError('value does not contain any values... thats shouldn\'t happen')
+        if type(value[0]) == tuple:
+            # Good thats what we expect and want to interpolate
+            return np.interp(freq, *zip(*value))
+
 # ============================================================================ #
 
 
@@ -823,6 +853,38 @@ def setAttenuation(self, Att):
 # ============================================================================ #
 
 
+class Filter(genericTwoPort):
+    """
+    | A filter device.
+
+    Parameters
+    ----------
+    name : str
+        device name
+    Att : list of (f, Att)
+        Attenuation representation in [dB]
+    """
+
+    def __init__(self, name, Att, OP1dB=None):
+        """
+        Parameters
+        ----------
+        name : str
+            device name
+        Att : list of (f, Att)
+            Attenuation representation in [dB]
+        OP1dB : numpy.float
+            Output Signal Compression Point in [dB]
+        """
+
+        Tn = [(f, 10**(att/10) * RFMath.T0 - RFMath.T0) for f, att in Att]
+        Gain = [(f, -att) for f, att in Att]
+        super().__init__(name, Gain=Gain, Tn=[0, Tn], P1=[0, OP1dB], IP3=[0, None])
+
+
+# ============================================================================ #
+
+
 class SPDT(AbstractDevice):
     """
     | An spdt device.

setup.py

@@ -4,7 +4,7 @@
     long_description = fh.read()
 
 setuptools.setup(name='rf-linkbudget',
-                 version='1.0.1',
+                 version='1.0.2',
                  description='A simple rf-linkbudget calculation tool',
                  url='https://github.com/hwengineer/rf_linkbudget',
                  author='Alexander Ott',