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Appendix 79
Avaya WLAN 2332 Series Outdoor Solution Guide
Radiation Patterns and 3-dB Beamwidth
The radiation patterns of an antenna describe how the antenna directs the energy it radiates. As stated earlier,
an antenna cannot radiate more total energy than is delivered to its input. All antennas, if 100% efficient, will
radiate the same total energy for equal input power, regardless of the shape of the radiating pattern.
In many cases, the convention of an E-plane and H-plane pattern is used in the presentation of antenna pattern
data. The E-plane is the plane that contains the antenna's radiated electric field potential while the H-plane is
the plane that contains the antenna's radiated magnetic field potential. These planes are always orthogonal. For
dipole and Yagi antennas, the E-plane is always in the plane parallel to the linear antenna elements.
The information obtained from these plots includes the 3-dB beamwidth. The 3-dB beamwidth of an antenna
is a measure of the angular width or spread of the signal at the points on the radiating signal where the power
has been reduced to 1/2 of its original power level.
Additional factors that affect the antenna's efficiency are the antenna side lobe level and front to back ratio.
These parameters are measures of how much energy the antenna radiates outside of its main beam. The side
lobe level describes the relative level of minor pattern lobes outside the main beam while the front to back ratio
describes the level of radiation directly opposite (180 degrees away) from the main beam. Ideally, these levels
should be as low as possible since they reduce the directivity and efficiency of the main beam. When
transmitting, the presence of side and back lobes may cause interference to other nearby access points, and
when receiving, they may allow interference into the access point from surrounding WLANs or rogue devices.
Directivity and Gain
The directivity of an antenna is a relative measure of how an antenna focuses or directs the energy it radiates in
the main beam of the antenna pattern. It is defined as the ratio of the antenna radiation intensity in a specific
direction to the radiation intensity of an isotropic radiator for the same radiated power. The higher the
directivity, the more focused the antenna pattern.
The gain of an antenna is closely related to its directivity, but takes into consideration the losses in the antenna,
such as conduction and dielectric losses, as well as, the directional capabilities of the antenna. By definition, it
is equal to 4 times the ratio of the maximum radiation intensity to the net power accepted by the antenna at its
input.
Gain is measured on a far-field outdoor test range by comparing the gain of the antenna under test to that of a
pre-calibrated Standard Gain antenna:
Table 14: VSWR, % Reflected Power and Transmission Loss
VSWR % Reflected Power Transmission Loss [dB]
1.0 : 1 0.00 0.00
1.1 : 1 0.23 0.01
1.2 : 1 0.83 0.04
1.5 : 1 4.00 0.18
2.0 : 1 11.11 0.51
2.5 : 1 18.37 0.88
3.0 : 1 25.00 1.25
- Solution Guide 1
- Contents 3
- 6 Contents 6
- Outdoor Solution 7
- Customer service 8
- 2332 Access Points 9
- Canadian IC statement 10
- Declaration of conformity 11
- Радио Модел 12
- Community 14
- Transmit Power Control (TPC) 15
- Taiwan Compliance Statement 16
- United States and Canada 18
- 2.4 GHz Band 18
- 5.0 GHz Bands 18
- External Antenna Statement 22
- Country 2.4 GHz 5.0 GHz 23
- Warning conventions 27
- Radio safety warnings 29
- Earth ground warning 35
- Introduction 39
- Package contents 40
- Signal path distance 41
- Antenna polarization 41
- Signal path clearance 41
- Physical site survey 41
- Physical site 42
- Hardware installation 43
- Installation 47
- Grounding principles 48
- Figure 6. Drip Loops 49
- Outdoor external antennas 50
- Coax cable seal installation 51
- Software installation 53
- Site Planning 58
- Safety Precautions 59
- Reference Information 60
- Applying coax seal tape 61
- Figure 14. Mounting Bracket 62
- Terminal Strip Connection 66
- Software 67
- Appendix 69
- Surge Suppression 70
- Appendix 75 75
- 76 Appendix 76
- Appendix 77 77
- Antenna properties 78
- Appendix 79 79
- Effective Radiated Power 80
- Polarization 80
- RF Propagation and Path Loss 82
- Appendix 83 83
- 84 Appendix 84
- Appendix 85 85
- 5.15 GHz 86
- 5.47 GHz 86
- 5.85 GHz 86
- 88 Appendix 88
- Appendix 91 91
- 92 Appendix 92
- Appendix 93 93
- 94 Appendix 94
- Appendix 95 95
- 96 Appendix 96
- Appendix 97 97
- 98 Appendix 98
- Appendix 99 99
- 100 Appendix 100
- Appendix 101 101
- 102 Appendix 102
- Appendix 103 103
- 104 Appendix 104
- 2462 MHz 105
- 2412 MHz 105
- 2437 MHz 105
- 106 Appendix 106
- Appendix 107 107
- 108 Appendix 108
- Appendix 109 109
- 110 Appendix 110
- Appendix 111 111
- 112 Appendix 112
- Appendix 113 113
- 114 Appendix 114
- Appendix 115 115
- 116 Appendix 116
- Appendix 117 117
- 118 Appendix 118
- Appendix 119 119
- Figure 23. Top view 119
- Figure 24. Bottom view 119
- 120 Appendix 120
- Figure 25. Side view 120
- Figure 26. Mounting screws 120
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