1. Altai Super WiFi Training WiFi Network Planning
Professional Services
Altai Technologies Limited

2. Module Outline Basic WiFi Technology Wireless Network Planning
Coverage Planning
Site Survey
Wireless Backhaul Link

3. Basic WiFi Technology

4. WiFi Standard 11b 11g 11a 11n HT 20 11n HT 40 Frequency band 2.4GHz
2.4 or 5 GHz
Maximum Data Rate
11Mbps
54Mbps
130Mbps
300Mbps
Usage
Access
Bridging
Both

5. Wireless Operation Modes
Bridge
Access Point
CPE
Indoor Access Point
Internet 1 2 3 4
Repeater
Access Point (AP Mode) – 2.4GHz for laptop access
Repeater Mode – 2.4GHz for wireless in and wireless out
CPE Mode – 2.4GHz for wireless in and Ethernet out
Bridge Mode – 5GHz for wireless backhaul link

6. Wi-Fi Spectrum 802.11b/g/ng are operating at 2.4GHz
Different countries have different spectrum allocated for Wi-Fi
To minimize the overlapping, it is recommended to have a separation 25MHz, i.e. 5 channels.
Example of Separate Channels at 2.4GHz are 1, 6, 11

7. Available Channel Number
Wi-Fi Spectrum
802.11a, na are operating at 5GHz
All 5GHz channels are “non-overlapping” channels.
Operation Radio
Spectrum (GHz)
Available Channel Number
802.11a
5180MHZ MHZ
36,40,44,48,52,56,60,64
5500MHZ MHZ
100,104,108,112,116,120, 124,128,132,136,140
802.11na (HT20)
802.11na (HT40ext CH+1)
5180MHZ MHZ
36,44,52,60
5500MHZ MHZ
100,108,116,124,132
802.11na (HT40ext CH-1)
5200MHZ MHZ
40,48,56,64
5520MHZ MHZ
104,112,120,128,136

8. Wireless Network Planning

9. Wireless Network Planning
Determine the coverage area
and requirement
Preliminary determine number
of sites and locations
Taking photos
Determine power supply and backhaul
determine a preliminary pole location
Perform site survey (Site Info stored in the database)
Conduct a coverage survey
(Optional)
May need to re-determine the pole, or even, site location

10. Wireless Network Planning
Site acquisition & Installation
Go back and determine antenna configuration should be changed, or more sites are required
Site configuration &
acceptance test OK
Determine if the coverage and service meet the requirements. No
Yes
Keep maintenance

11. Wireless Network Requirements
Target Coverage Area
Dimension of the area on a map
User distribution
Building/Trees distribution and height
Anticipated Number of Users
Potential subscribers
Can take reference to no of schools, mobile phone subscriber number, WiMax users
Wireless Application
Voice over IP
Surveillance camera
or web surfing
Wired Backhaul
Uplink and downlink bandwidth
Availability and extensibility location
Installation Site
Possible site acquisition
Power availability

12. Coverage Area Estimation
In sub-urban area, we assumed cell radius of A8n to be 0.35 km
In dense-urban area, we assumed cell radius of A8n to be 0.25 km
In sub-urban area, we assumed cell radius of A8Ein to be 0.60 km
In dense-urban area, we assumed cell radius of A8Ein to be 0.40 km

13. Network Capacity (A8Ein)
Estimated maximum throughput per user is 1 Mbps
An average of 20 Mbps throughput per A8Ein
20 concurrent users at maximum traffic for the A8Ein
Typical activity ratio is 20%
100 concurrent users per A8Ein
Oversell ratio is 4
100 x 4 = 400 subscribers per A8Ein

14. Site Survey Site information Stored in a database for reference
Site Location
Site Location Details
Site Photo
Photo of each sector view

15. Site Survey N Example Site Map Example Site ConfigurationB D C
Example Site Map
Configuration
Bearing Downtilt
Sector A 10 5
Sector B 70 5
Sector C
Sector D
Example Site Information
Example Site Configuration

16. Site Acquisition Site Negotiation Power Supply and Wired Network Link
Antenna Installation Planning
Site Confirmation
Installation Layout and Construction Plan
Site Information Database

17. Site Installation (A8Ein)
North
0.7m
0.7m A
1 m
Side-View 3
0.8m
1 m
Side-View 3
>1.7 m
Rooftop
Height  25m
Pole base
1m x 1m x 0.125m
Rooftop

18. Coverage Planning

19. Calculate Downtilt The cell coverage could be confirmed by downtilt
Assume
h : antenna height
d : distance
 : downtilt angle
The down tilt angle is:
 = arc-tan( h / d)
Example 1:
h = 20m, d = 500m
 = 2.3 
Example 2:
h = 80m, d = 500m
 = 9   h d

20. Case Study – Scenario 1 Case
Antenna at 20/F rooftop ( h = 80m), A8Ein vertical beam width is 12 
Scenario 1
If the user needs to focus on the area of 500m location:
then, d = 500m, h = 80m
= 9 
Note:
d1 = 290m
d2 = 1,479m  h d d1 d2

21. Case Study – Scenario 2 Case
Antenna at 20/F rooftop ( h = 80m), A8Ein vertical beam width is 12 
Scenario 2
If the user needs to cover up to 500m, but most the WiFi clients are located close to the radio site,
then, d2 = 500m, h = 80m
- Downtilt = 9  + 6  = 15 
Note:
d = 298m
d1 = 198m  h
= 9  d d1 d2

22. Angle Meter Depends on Antenna height Antenna vertical beam-width
Distance required
WiFi Users Distribution
Angle Meter

23. East Palo Alto, USA Objective Problem Solution
Community Interact Program providing Internet access to non-profit and charity organizations
Problem
Original mesh AP supports less than 2Mbps with latency problems
Solution
Community Wireless selects Altai as the replacement product
12 BTS deployed in an area of 7 sq. km
Blanket 70% of East Palo Alto City
Provide coverage to over 35,000 residents

24. East Palo Alto, CA, USA

25. Estimated Coverage

26. Hub Site Locations
Hub 2
2 km
Hub 1

27. Location of the Test SiteB6 B7 B8 B9
Site 11 B4
Hub 2
Turbo 11a
switch B2
Hub 1
Internet
switch

28. Site 1: Predicted/Planned Coverage
Predicted Coverage
Measured Coverage
0.32 mile
Site 1

29. Site 2: Predicted/Planned Coverage
0.32 mile
Predicted Coverage
Measured Coverage

30. Site Survey

31. Field Measurement in Hangzhou
Site 2
Site 1

32. Site Location Zhong Shan Road North North Building Height  75m
Lower Rooftop
(19/F) P2
Upper
Rooftop
Zhong Shan Road North
Two site locations P1

33. Site 1
Antennas A8

34. Northwest (Wulin Square) South (Zhong Shan Road North)
View from Site 1
C (280°)
D (310°)
B (220°)
Northwest (Wulin Square)
West
A (150°)
South (Zhong Shan Road North)

35. Site 1, Sector A
Zhongshan Road North

36. Site 1, Sector A (upward)
Seeing the building from Fengqi Road (at 250m distance)
Site 1

37. Wireless Backhaul Link

38. WiFi Bridge 5GHz External Antenna A2 WiFi Bridge 802.11na 5GHz Switch
A8Ein Super WiFi
802.11b/g/ng 2.4GHz
A2 WiFi Bridge
802.11na 5GHz
Switch
A2 WiFi AP
802.11b/g/ng 2.4GHz
Triple play enabled by Altai City-wide WiFi
Typical applications over city-wide WiFi include voIP, online gaming, video streaming with support of fast handoff
B5 Ultra Bridge
5GHz Bridge
Switch
A8-Ein Super WiFi
802.11b/g/ng 2.4GHz

39. WiFi Bridge External Antenna Options for A8Ein and A2e
High gain directional antenna: 20dBi
WiFi Bridge Requirements
Clear Line of Sight (LOS)
Fine tuning antenna alignment
Configuring bridge distance in web admin
Common Bridge Distance: 5~10km
B5 Bridge Ultra Long Distance: 20~80km

40. Coverage Mapping

41. Coverage mapping
Coverage mapping is important step to examine the result of the network planning.
Measure the DL RSSI of different AP along the path in specified area.
Tools for WiFi Coverage mapping
InSSIDer with GPS

42. Coverage mapping result example

43. Coverage mapping Result of the coverage mapping is used to
Adjust the down tilt, direction, height and transmit power of AP
Determine if additional sites required to add to improve the network coverage.
Coverage test is always encouraging before site acquisition of new sites to confirm the new sites coverage
Setup A8Ein in the new sites temporary with tripod and do coverage mapping.

44. Thank You