Everything your parents never told you about antennas

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Everything your parents never told you about
antennas

• Johan Führi
• Design Engineer
• Poynting Antennas, South Africa
• MUM, Poland 2008

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Poynting Antennas

• Antenna and enclosure design and manufacture
• Company size 180 people, 2600m2 factory
• 20 RD staff (3xPh.D, M.Scs, B.Scs, Techs)
• Turnover USD 7.5 million p/a.
• About 40,000 units per month output.
• Export to Europe, Australia, Malaysia, Singapore,
  Israel and United States.
• Various low cost, high performance fabrication
  technologies developed in-house.
• Cutting edge outdoor enclosure portfolio with
  proven applications globally.

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Overview

• What is an antenna?
• How does it work?
• What antennas cannot do
• Antennas in practice
• New technologies in antenna/enclosure systems

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What is an Antenna?

• The wireless telegraph is not difficult to
  understand. The ordinary telegraph is like a
  very long cat. You pull the tail in New York and
  it meows in Los Angeles. The wireless is the
  same, only without the cat. Albert Einstein.
• Mechanical device that converts an electrical
  signal into an electromagnetic wave and
  vice-versa
• It is not an AERIAL

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How does antennas work?

• Antenna focuses outgoing and incoming signals
• In a particular direction
• With a particular pattern

• More gain more focusing in the firing
  direction
• In TX, less signal sent in other directions
• In RX, antenna is deafer in other directions
• More signal in the firing direction
• Lower interference
• More signal higher range/data rates

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How does antennas work?

• More gain larger size
• Panel/dish antennas gain proportional to area

• Limited by physics
• Size/gain trade-off
• Must keep losses down

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What antennas cannot do

• Antenna bandwidth
• Cant work over arbitrarily wide number of
  channels
• Frequency limited

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How does antennas work?

• In summary
• Antennas focus energy to increase signal
• High gain means less signal in other directions
• Gain depends on antenna size
• Cannot cheat physics must reduce loss
• Antennas can work differently in different
  channels

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Antennas in practice

• Connecting to the Electronics
• Choosing the right antenna
• Distribution
• High site
• CPE
• Point-to-Point
• Indoor

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Connecting to the Electronics

• Keep the radio close to the antenna
• RF cable kept short
• Negligible losses best possible signal
• Lower susceptibility to lightning impulse

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Mounting Electronics Outdoor
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Choosing the right antenna

• Omni-directional antennas The Ultimate Solution?

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Choosing the right antenna

• Sector Antennas
• Cover only the areas that you need to cover
• Multiple sector antennas per enclosure
• One antenna per radio

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Choosing the right antenna

• Client Premises Equipment CPE
• What is important?
• Easy installation
• Aesthetics
• Good performance
• Low cost

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iPoynt
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iPoynt
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iPoynt
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iPoynt
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Choosing the right antenna

• Point-to-Point
• High gain dish/panels with heavy duty enclosures
  (long range)
• Fully integrated medium gain solution (medium
  range)

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Choosing the right antenna

• High gain antennas
• Narrow beamwidth
• Cutting out noise
• High gain
• Improved signal strength
• Higher data rates
• Grid Antennas
• Lower wind resistance

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Choosing the right antenna

• Indoor Antennas
• Main problem is Multipath Interference
• Space diversity
• Polarisation diversity
• Relatively low gain antenna wide beamwidth
• Going through walls unreliable signal

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Choosing the right antenna - Diversity
WLAN-A0030 Integrated quad diversity (spatial
pol) 2.4 GHz 8dBi Patch antennas Indoor MIMO AP
Enclosure
WLAN-A0032 Dual integrated 2.4 GHz 14dBi Panel
antennas Indoor AP Enclosure Outdoor
diversity/2 channel link
WLAN-A0033 Dual diversity 2.4 GHz 8dBi
Omnis Integrated 5GHz 20dBi panel Local Access
Node
WLAN-A0031 Integrated diversity 2.4 GHz 7dBi
Omnis Outdoor AP Enclosure
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To the future

• High performance antenna technology
• Optimisation-based design
• Wide band
• Low loss
• Low sidelobes

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To the future

• Integrated Multi-sector enclosures
• Compact integrated outdoor enclosure for 5GHz
• Quad-reconfiguarable sector array
• 4x 90 degrees
• 2x180 degrees
• 1x360 degrees

4x 90 degrees
2x 180 degrees
1x 360 degrees
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To the future

• Antenna sharing for Nstreme 2
• Only one pair of antennas to run Nstreme 2
• Minimise installation costs and mounting space
• Need wideband antenna, diplexer

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To the future

• Dual polarised antenna enclosure
• Two antennas in one enclosure, HP and VP
• Single Nstreme 2 enclosure

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Thank you