From: Bio-inspired optimization algorithms applied to rectenna design

F | Center frequency of antenna |
A_{
e
}
| Antenna efficiency of antenna |

B | Band width of antenna |
R
_{
L
}
| Return loss of antenna |

P
_{
in
}
| Input power of rectenna |
P
_{
out
}
| Output power of rectenna |

η
_{
a
}
| Efficiency of antenna |
η
_{
m
}
| Efficiency of matching circuit |

η
_{
r
}
| Efficiency of rectifier circuit |
P
_{
T
}
| Transmitted power from source |

W
| Width of RMPA |
L
| Length of RMPA |

W
_{0}
| Feed width of RMPA |
L
_{
d
}
| Inset feed length |

g
| Notch width |
ε
_{0}
| Vacuum dielectric constant |

X
_{
min
}
| Minimum constraint of antenna size |
X
_{
max
}
| Maximum constraint of antenna size |

μ
_{0}
| Vacuum permeability |
Z
_{
in
}
| Antenna input impedance |

Γ
| Voltage reflection coefficient | VSWR | Voltage standing wave ratio |

Q
_{
rad
}
| Quality factor due to radiation losses |
Q
_{
c
}
| Quality factor due to conduction losses |

Q
_{
d
}
| Quality factor due to dielectric losses |
Q
_{
sw
}
| Quality factor due to surface waves |

Q
_{
t
}
| Total quality factor |
tanδ
| Loss tangent of the substrate material |

G
| Antenna gain |
v
_{0}
| The speed of EM wave |

k
_{0}
| Spatial angular frequency of wave |
G
_{
abs
}
| Absolute gain |

P
_{
rad
}
| Radiation power of antenna |
U
_{
max
}
| Maximum radiation intensity |

D
_{0}
| Directivity of antenna with single slot |
D
_{
AF
}
| Directivity of array factor AF |

e
_{
BW
}
| Efficient bandwidth ratio |
F
_{
AL
}
| Aimed lower conner frequency |

F
_{
AH
}
| Aimed upper conner frequency |
F
_{
DL
}
| Designed lower conner frequency |

F
_{
DH
}
| Designed upper conner frequency |
σ
| Conductivity of patch |

D
| Directivity of antenna |
e
_{
cd
}
| ntenna Radiation efficiency |