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Altai Super WiFi Training WiFi Network Planning. Professional Services Altai Technologies Limited. Module Outline. Basic WiFi Technology Wireless Network Planning Coverage Planning Site Survey Wireless Backhaul Link. Basic WiFi Technology. WiFi Standard. Wireless Operation Modes.
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Altai Super WiFiTrainingWiFi Network Planning Professional Services Altai Technologies Limited
Module Outline Basic WiFi Technology Wireless Network Planning Coverage Planning Site Survey Wireless Backhaul Link
Wireless Operation Modes Access Point Bridge 1 2 3 4 CPE Repeater Internet Indoor Access Point • 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
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
Wi-Fi Spectrum • 802.11a, 802.11na are operating at 5GHz • All 5GHz channels are “non-overlapping” channels.
Wireless Network Planning Taking photos Determine power supply and backhaul determine a preliminary pole location Determine the coverage area and requirement Preliminary determine number of sites and locations 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
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
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 Email or web surfing Wired Backhaul Uplink and downlink bandwidth Availability and extensibility location Installation Site Possible site acquisition Power availability
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
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
Site Survey Site information Stored in a database for reference Site Location Site Location Details Site Photo Photo of each sector view
Site Survey N A B D C Example Site Map Configuration BearingDowntilt Sector A 10 5 Sector B 70 5 Sector C 130 10 Sector D 190 10 Example Site Configuration Example Site Information
Site Acquisition Site Negotiation Power Supply and Wired Network Link Antenna Installation Planning Site Confirmation Installation Layout and Construction Plan Site Information Database
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
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
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
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
Angle Meter Depends on Antenna height Antenna vertical beam-width Distance required WiFi Users Distribution Angle Meter
Objective 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 East Palo Alto, USA
Hub Site Locations Hub 2 2 km Hub 1
Location of the Test Site Site 06 Site 10 Site 09 Site 05 Site 03 B6 B7 B9 B8 Site 11 Hub 2 B4 Turbo 11a switch Hub 1 B2 Internet switch
Site 1: Predicted/Planned Coverage Predicted Coverage Measured Coverage 0.32 mile Site 1
Site 2: Predicted/Planned Coverage Predicted Coverage 0.32 mile Measured Coverage Site 2
Field Measurement in Hangzhou Site 2 Site 1
Site Location North Building Height 75m Lower Rooftop (19/F) P2 Upper Rooftop Zhong Shan Road North Two site locations P1
Site 1 Antennas A8
View from Site 1 D (310°) C (280°) B (220°) Northwest (Wulin Square) West A (150°) South (Zhong Shan Road North)
Site 1, Sector A Zhongshan Road North
Site 1, Sector A (upward) Seeing the building from Fengqi Road (at 250m distance) Site 1
WiFi Bridge 5GHz External Antenna 802.11na 5GHz A2 WiFi Bridge Switch A8Ein Super WiFi 802.11b/g/ng2.4GHz B5 Ultra Bridge A2 WiFi Bridge 802.11na 5GHz 5GHz Bridge Switch Switch A2 WiFi AP A8-Ein Super WiFi 802.11b/g/ng2.4GHz 802.11b/g/ng2.4GHz
WiFi Bridge External Antenna Options for A8Ein and A2e High gain directional antenna: 20dBi WiFiBridge 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
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
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.