Feat/antenna 1245 fs

sharc/antenna/antenna_f1245_fs.py

@@ -0,0 +1,196 @@
+
+# -*- coding: utf-8 -*-
+"""
+Created on Wed Apr 4 17:08:00 2018
+@author: Calil
+"""
+import matplotlib.pyplot as plt
+from sharc.antenna.antenna import Antenna
+from sharc.parameters.imt.parameters_imt import ParametersImt
+from sharc.parameters.imt.parameters_imt import ParametersImt
+from sharc.parameters.imt.parameters_antenna_imt import ParametersAntennaImt
+from sharc.parameters.parameters_antenna import ParametersAntenna
+import numpy as np
+import math
+
+
+class Antenna_f1245_fs(Antenna):
+    """Class that implements the ITU-R F.1245 antenna pattern for fixed
+    satellite service earth stations."""
+
+    def __init__(self, param: ParametersImt):
+        super().__init__()
+        self.peak_gain = param.gain
+        lmbda = 3e8 / (param.frequency * 1e6)
+        self.d_lmbda = param.diameter / lmbda
+        self.g_l = 2 + 15 * math.log10(self.d_lmbda)
+        self.phi_m = (20 / self.d_lmbda) * math.sqrt(self.peak_gain - self.g_l)
+        self.phi_r = 12.02 * math.pow(self.d_lmbda, -0.6)
+
+    def calculate_gain(self, *args, **kwargs) -> np.array:
+        """
+        Calculate the antenna gain for the given parameters.
+
+        Parameters
+        ----------
+        *args : tuple
+            Positional arguments (not used).
+        **kwargs : dict
+            Keyword arguments, expects 'phi_vec', 'theta_vec', and 'beams_l'.
+
+        Returns
+        -------
+        np.array
+            Calculated antenna gain values.
+        """
+        # phi_vec = np.absolute(kwargs["phi_vec"])
+        # theta_vec = np.absolute(kwargs["theta_vec"])
+        # beams_l = np.absolute(kwargs["beams_l"])
+        off_axis = np.absolute(kwargs["off_axis_angle_vec"])
+        if self.d_lmbda > 100:
+            gain = self.calculate_gain_greater(off_axis)
+        else:
+            gain = self.calculate_gain_less(off_axis)
+            # idx_max_gain = np.where(beams_l == -1)[0]
+            # gain = self.peak_gain
+        return gain
+
+    def calculate_gain_greater(self, phi: float) -> np.array:
+        """
+        For frequencies in the range 1 GHz to about 70 GHz, in cases where the
+        ratio between the antenna diameter and the wavelength is GREATER than
+        100, this method should be used.
+        Parameter
+        ---------
+        phi : off-axis angle [deg]
+        Returns
+        -------
+        a numpy array containing the gains in the given angles
+        """
+        gain = np.zeros(phi.shape)
+        idx_0 = np.where(phi < self.phi_m)[0]
+        gain[idx_0] = self.peak_gain - 2.5e-3 * \
+            np.power(self.d_lmbda * phi[idx_0], 2)
+        phi_thresh = max(self.phi_m, self.phi_r)
+        idx_1 = np.where((self.phi_m <= phi) & (phi < phi_thresh))[0]
+        gain[idx_1] = self.g_l
+        idx_2 = np.where((phi_thresh <= phi) & (phi < 48))[0]
+        gain[idx_2] = 29 - 25 * np.log10(phi[idx_2])
+        idx_3 = np.where((48 <= phi) & (phi <= 180))[0]
+        gain[idx_3] = -13
+        return gain
+
+    def calculate_gain_less(self, phi: float) -> np.array:
+        """
+        For frequencies in the range 1 GHz to about 70 GHz, in cases where the
+        ratio between the antenna diameter and the wavelength is LESS than
+        or equal to 100, this method should be used.
+        Parameter
+        ---------
+        phi : off-axis angle [deg]
+        Returns
+        -------
+        a numpy array containing the gains in the given angles
+        """
+        gain = np.zeros(phi.shape)
+        idx_0 = np.where(phi < self.phi_m)[0]
+        gain[idx_0] = self.peak_gain - 0.0025 * \
+            np.power(self.d_lmbda * phi[idx_0], 2)
+        idx_1 = np.where((self.phi_m <= phi) & (phi < 48))[0]
+        gain[idx_1] = 39 - 5 * \
+            math.log10(self.d_lmbda) - 25 * np.log10(phi[idx_1])
+        idx_2 = np.where((48 <= phi) & (phi < 180))[0]
+        gain[idx_2] = -3 - 5 * math.log10(self.d_lmbda)
+        return gain
+
+    def add_beam(self, phi: float, theta: float):
+        """
+        Add a new beam to the antenna.
+
+        Parameters
+        ----------
+        phi : float
+            Azimuth angle in degrees.
+        theta : float
+            Elevation angle in degrees.
+        """
+        self.beams_list.append((phi, theta))
+
+    def calculate_off_axis_angle(self, Az, b):
+        """
+        Calculate the off-axis angle between the main beam and a given direction.
+
+        Parameters
+        ----------
+        Az : float or np.array
+            Azimuth angle(s) in degrees.
+        b : float or np.array
+            Elevation angle(s) in degrees.
+
+        Returns
+        -------
+        float or np.array
+            Off-axis angle(s) in degrees.
+        """
+        Az0 = self.beams_list[0][0]
+        a = 90 - self.beams_list[0][1]
+        C = Az0 - Az
+        off_axis_rad = np.arccos(
+            np.cos(
+                np.radians(a)) *
+            np.cos(
+                np.radians(b)) +
+            np.sin(
+                np.radians(a)) *
+            np.sin(
+                np.radians(b)) *
+            np.cos(
+                np.radians(C)),
+        )
+        off_axis_deg = np.degrees(off_axis_rad)
+        return off_axis_deg
+
+
+if __name__ == '__main__':
+    off_axis_angle_vec = np.linspace(0.1, 180, num=1001)
+    # initialize antenna parameters
+    param = ParametersAntenna()
+    param.frequency = 2155
+    param_gt = ParametersAntennaImt()
+    param.gain = 33.1
+    param.diameter = 2
+    antenna_gt = Antenna_f1245_fs(param)
+    antenna_gt.add_beam(0, 0)
+    gain_gt = antenna_gt.calculate_gain(
+        off_axis_angle_vec=off_axis_angle_vec,
+    )
+    param.diameter = 3
+    antenna_gt = Antenna_f1245_fs(param)
+    gain_gt_3 = antenna_gt.calculate_gain(
+        off_axis_angle_vec=off_axis_angle_vec,
+    )
+    param.diameter = 1.8
+    antenna_gt = Antenna_f1245_fs(param)
+    gain_gt_18 = antenna_gt.calculate_gain(
+        off_axis_angle_vec=off_axis_angle_vec,
+    )
+
+    fig = plt.figure(
+        figsize=(8, 7), facecolor='w',
+        edgecolor='k',
+    )  # create a figure object
+    plt.semilogx(off_axis_angle_vec, gain_gt, "-b", label="$f = 10.7$ $GHz,$ $D = 2$ $m$")
+    plt.semilogx(off_axis_angle_vec, gain_gt_3, "-y", label="$f = 10.7$ $GHz,$ $D = 3$ $m$")
+    plt.semilogx(off_axis_angle_vec, gain_gt_18, "-g", label="$f = 10.7$ $GHz,$ $D = 1.8$ $m$")
+
+    plt.title("ITU-R F.1245 antenna radiation pattern")
+    plt.xlabel(r"Off-axis angle $\phi$ [deg]")
+    plt.ylabel("Gain relative to $G_m$ [dB]")
+    plt.legend(loc="lower left")
+    # plt.xlim((phi[0], phi[-1]))
+    plt.ylim((-20, 50))
+    # ax = plt.gca()
+    # ax.set_yticks([-30, -20, -10, 0])
+    # ax.set_xticks(np.linspace(1, 9, 9).tolist() + np.linspace(10, 100, 10).tolist())
+    plt.grid()
+    plt.show()

sharc/antenna/antenna_factory.py

@@ -12,6 +12,7 @@
 from sharc.antenna.antenna_s580 import AntennaS580
 from sharc.antenna.antenna_s1528 import AntennaS1528
 from sharc.antenna.antenna_s1855 import AntennaS1855
+from sharc.antenna.antenna_f1245_fs import Antenna_f1245_fs
 from sharc.antenna.antenna_s1528 import AntennaS1528, AntennaS1528Leo, AntennaS1528Taylor
 from sharc.antenna.antenna_beamforming_imt import AntennaBeamformingImt
 
@@ -49,6 +50,8 @@ def create_antenna(
                 return AntennaS465(antenna_params.itu_r_s_465_modified)
             case "ITU-R S.1855":
                 return AntennaS1855(antenna_params.itu_r_s_1855)
+            case "ITU-R F.1245_fs":
+                return Antenna_f1245_fs(antenna_params.itu_r_f_1245_fs)
             case "ITU-R Reg. RR. Appendice 7 Annex 3":
                 return AntennaReg_RR_A7_3(antenna_params.itu_reg_rr_a7_3)
             case "MSS Adjacent":

sharc/parameters/parameters_antenna.py

@@ -29,7 +29,8 @@ class ParametersAntenna(ParametersBase):
         "ITU-R-S.1528-Taylor",
         "ITU-R-S.1528-Section1.2",
         "ITU-R-S.1528-LEO",
-        "MSS Adjacent"]
+        "MSS Adjacent",
+        "ITU-R F.1245_fs"]
 
     # chosen antenna radiation pattern
     pattern: typing.Literal["OMNI",
@@ -44,7 +45,8 @@ class ParametersAntenna(ParametersBase):
                             "ITU-R-S.1528-Taylor",
                             "ITU-R-S.1528-Section1.2",
                             "ITU-R-S.1528-LEO",
-                            "MSS Adjacent"] = None
+                            "MSS Adjacent",
+                            "ITU-R F.1245_fs"] = None
 
     # antenna gain [dBi]
     gain: float = None
@@ -94,6 +96,45 @@ class ParametersAntenna(ParametersBase):
         default_factory=ParametersAntennaS672,
     )
 
+    @dataclass
+    class ParametersAntennaRF1245(ParametersBase):
+        """
+        Parameters for ITU-R F.1245 antenna model. It's commonly used
+        for fixed service antennas.
+
+        Paremeters
+        ----------
+        gain : float, default=-25
+            Antenna gain in dB.
+        diameter : float, optional
+            Antenna diameter in meters.
+        frequency : float, optional
+            Operating frequency.
+        """
+        gain: float = -25
+        diameter: float = None
+        frequency: float = None
+
+        def validate(self, ctx):
+            """
+            Validate the antenna parameters for correctness.
+
+            Parameters
+            ----------
+            ctx : str
+                Context string for error messages.
+            Raises
+            ------
+            ValueError
+                If any parameter is invalid.
+            """
+            if None in [self.gain, self.diameter, self.frequency]:
+                raise ValueError(f"{ctx}.antenna_3_dB should be set to a number")
+
+    itu_r_f_1245_fs: ParametersAntennaRF1245 = field(
+        default_factory=ParametersAntennaRF1245,
+    )
+
     def set_external_parameters(self, **kwargs):
         """
         Set external parameters for all sub-parameters of the antenna.
@@ -198,6 +239,8 @@ def validate(self, ctx):
                 self.itu_r_s_672.validate(f"{ctx}.itu_r_s_672")
             case "MSS Adjacent":
                 self.mss_adjacent.validate(f"{ctx}.mss_adjacent")
+            case "ITU-R F.1245_fs":
+                self.itu_r_f_1245_fs.validate(f"{ctx}.itu_r_f_1245_fs")
             case _:
                 raise NotImplementedError(
                     "ParametersAntenna.validate does not implement this antenna validation!", )

sharc/station_factory.py

@@ -50,6 +50,7 @@
 from sharc.antenna.antenna_s672 import AntennaS672
 from sharc.antenna.antenna_s1528 import AntennaS1528
 from sharc.antenna.antenna_s1855 import AntennaS1855
+from sharc.antenna.antenna_f1245_fs import Antenna_f1245_fs
 from sharc.antenna.antenna_s1528 import AntennaS1528, AntennaS1528Leo, AntennaS1528Taylor
 from sharc.antenna.antenna_beamforming_imt import AntennaBeamformingImt
 from sharc.topology.topology import Topology
@@ -1327,6 +1328,8 @@ def generate_fs_station(param: ParametersFs):
             fs_station.antenna = np.array([AntennaOmni(param.antenna_gain)])
         elif param.antenna_pattern == "ITU-R F.699":
             fs_station.antenna = np.array([AntennaF699(param)])
+        elif param.antenna_pattern == "ITU-R F.1245_fs":
+            fs_station.antenna == np.array([Antenna_f1245_fs(param)])
         else:
             sys.stderr.write(
                 "ERROR\nInvalid FS antenna pattern: " + param.antenna_pattern,