**CORNER REFLECTOR ANTENNA (AIRIAN-GB 2011)**

**INTRODUCTION:**

The corner-reflector antenna is made up of two plane reflector panels and a dipole Element. This arrangement prohibits radiation in the back and side directions and hence makes the antenna more directional.

**Designed antenna calculation:**

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We designed a corner reflector antenna working on freq 1 GHz which will transmit and receive signal.

REFLECTOR DESIGN:

Above figure shows the geometry of the corner reflector antenna.

To design a reflector we need 5 parameters but the most important is the value of lambda on which all the parameters depends.

Using these calculation we can also make other corner reflectors.

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**FEED TO VERTEX DISTANCE (S):**

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The feed element we used is the dipole antenna. Dipole is placed parallel to the vertex a distance *s *away, as shown in figure.

The feed-to-vertex distance (s) is usually taken l / 3 < *s *< 2l / 3).

For each reflector, there is an optimum feed-to-vertex spacing. If the spacing becomes too small, the radiation resistance decreases and becomes comparable to the loss resistance of the system which results in an inefficient antenna.

For very large spacing, the system produces undesirable multi-lobes, and it loses its directional characteristics.

**THE APERTURE (D):**

The aperture of the corner reflector (D) is usually made between one and two wavelengths (l < *D *< 2 l) .

**REFLECTOR ANGLE:**

The angle between the reflector is 90^{}

^{ }

**LENGTH OF THE SIDES:**

The length of the sides of the 90^{}corner reflector is mostly taken to be twice the distance from the vertex to the feed (*L *» 2*s*).

**THE HEIGHT (H):**

The height (H) of the reflector is usually taken to be about 1.2 to 1.5 times greater than the total length of the feed element, in order to reduce radiation towards the back region from the ends.

**AS PER OUR CALCULATIONS:**

- FREQ= 1GHZ.
- C=300000000m/s
- Lambda=c/f
- We got this
- 0.30m=30 cm
- As per our requirement
- lambda/2=15cm

Now we will formulate the reflector design parameters which depend upon lambda.

The feed-to-vertex distance (10< *s *< 20) we Choose =15cm.

The Aperture (30< *D *< 60 ) we choose =40cm.

Length ( *L *» 2*s*) L=2(15)=30cm.

The height is 1.2 to 1.45 times greater than the length which is 36 cm as in our design.

**Specifications:**

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**Model : GB-AIR2011 **

Frequency | 1Ghz |

Impedance | 50ohms |

Polarization | vertical |

Gain | 14.6dB |

H-plane beam width | 44.82 |

E-plane beam width | 38.64 |

Connector | N female |

Dimensions | 36x30x15 (cm) |

Weight | |

material | Aluminum(metal) |

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**Results:**

We performed different tests in lab.

**Test 1 :**

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TEST 2

NOW THE FINAL 3D VIEW:

Conclusion:

- With reflector HPBW =44’
- With out reflector
- HPBW =78’
- Means the directivity and gain increases.

REFERENCE:

- C.A. Balanis, .
*Antenna Theory: Analysis and Design*. Third edition, John Wiley& Sons, 2005, - R.C. Johnson and H. Jasik, .
*Antenna Engineering Handbook*., second edition,McGraw-Hill Book Company, 1984. - Fundaments of applied Electromagnatics 2001 media edition Fawwaz T. Ulaby

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