FreedomBox for Communities/Wi-Fi Towers
Wi-Fi is made available to users in the community by setting Wi-Fi access points at various locations in the community area. If suitable locations on existing buildings (such as tall water tanks) can be found then Wi-Fi towers are not necessary. The following section describes how to erect and setup a Wi-Fi tower.
- Wi-Fi routers should be placed at sufficient height above the ground level so that the signal reaches optimal distance. The optimal height at which a Wi-Fi access point can be placed is between 6 m and 15 m in a village with mostly one or two story buildings.
- Tower should be equipped to host not only the Wi-Fi access point but also power supply and an Ethernet hub (if there there are multiple Wi-Fi access points on the same tower.
- Towers should be installed strongly enough that they stand erect against strong winds during extreme climate events.
- The Wi-Fi towers should be placed at suitable place such that the strength of signal can be properly distributed across the expected area.
Physical Components of a Wi-Fi Tower
editFollowing are the physical components of a Wi-Fi tower found to be work well in some FreedomBox community deployments while remaining very cost effective:
- A galvanized metal pipe of length 6 m and diameter 2 inch
- Role - This pipe is the gives the tower it's height and becomes the central main pipe for the tower. One end of the pipe sits on the foundation plate and other end holds the antenna pipe. Also, in the middle, the pipe also holds the power box.
- Making - A galvanized metal pipe of length 6 m and diameter 2 inches should be purchased from the market. This length is a readily available length (these are also called 20 ft pipes). To integrate this pipe with the other components of the tower we need to drill two holes on the either ends of the tower. Screws, washers and bolts fitting the size of drilled holes should also be purchased and used during installation. With holes drilled on the either ends the pipe is ready for use.
- A galvanized metal pipe of length 1 m and diameter 1.5 inch diameter
- Role - All the antennae are held on to the tower using this pipe. Additional clamps (support pieces), which hold the antennae are fixed on to this 1 m pipe.
- Making - A galvanized metal pipe of length 6 m and diameter 1.5 inch should be purchased from the market. This 6 m pipe should be cut into six pipes of 1 m each. Only one of such piece will be used in a single tower (remaining pieces can be used for other towers). Two holes of the same diameter as holes drilled on 6 m pipe should be drilled at one end of the pipe. The distance between holes should be same as distance between holes drilled on 6 m pipe. With holes drilled on a single end the pipe is ready for installation.
- Installation - This pipe should be inserted into the 6 m pipe such that the holes of the both the pipes match. Then they are both fastened by driving a screw through the holes of both pipes and tightening with bolts and washers.
- 5 mm Guy-Wire of length 25 m
- Role - Guy wire makes the tower withstand extreme climate such as strong winds. Further, it helps bring down the tower smoothly for any maintenance.
- Making - Purchasing 5 mm diameter Guy-Wire from market. Wire is also called guy-wire, guide, guy-rope or guy in the market. Other than purchasing the wire, other important items are buckles and a cutter. Two types of buckles are used to tie the wire. First is a bulldog buckle and the other is a turnbuckle. Along with buckles we also need L-shape hooks and triangle ring plate. 25m guy-wire is cut into 3 pieces. Each piece, is tied at one end to triangle plate with rings and other end to L-shape hook firmly buried in the ground.
- Foundation plate/stool
- Role - It is on this component that the whole tower rests on. The cross legs are put deep into the ground or mortar and fixed firmly.
- Making - Making the foundation stool requires welding work. First, a 1x1 ft square plate should be purchased. This plate should be horizontal at exactly ground level after final installation with one side facing up and one side facing down. Two support plates should be welded, on the top side of the plate, orthogonal to foundation plate with enough distance between them for the 6 m / 2 inch diameter pipe to sit between them. Two holes should be drilled to these support plates such that they are inline with holes of the bottom end of the 6 m pipe that sits on this foundation stool. Foundation stool should further be welded with cross legs, so that when the stool is put into the ground or foundation mortar, stool fits firm and strong to the base. Cross legs are nothing but 1.5" pipes that are welded to bottom side of the foundation plate. With cross legs welded on top side and support plates welded on the bottom side, we have the foundation stool ready.
- Installation - Dig a hole deep enough that the entire stool goes into the ground and the foundation plate is at the ground level exactly. Place the stool in the ground and fill it with stones and dirt. Another option is to use concrete.
- Antenna Clamps
- Role - This clamp fixes antenna to main tower. Each antenna needs one clamp to be fixed to the tower.
- Making - Clamps are made using a flat metal piece bent to the round outer shape of 1.5 " diameter pipe. Along with antennae another clamp is already given with holes drilled on it. Same holes need to be drilled on clamps in vertically opposite direction. This helps us change the antenna angle.
- Power Box
- Role - Power box is a weather-proof enclosure in which all the power connections and the Ethernet hub are put together.
- Making - A galvanized metal enclosure should be purchased. There should be circular openings at the bottom of the box to allow Ethernet and power cables to enter and leave the box. Box should be suitably arranged with power extension box with enough sockets to power all the antennae.
Assembly/Installation
edit- Assembling the foundation - A total for four holes need to be dug out. A foundation hole where we would want to install the tower, i.e., where the foundation stool goes in, needs to be dug out first. Later 3 more holes should be dug out around the foundation hole, such that the foundation hole would be interior to the imaginative triangle formed by 3 holes. After digging the holes, foundation stool should be put in the foundation hole and properly fixed by beating stones and mud into the hole. Similarly, guy wire hooks should be put into remaining 3 holes.
- Fixing the middle part - The middle part primarily has the 6 m pipe along with power box. Initially, bring the tower onto the foundation plate and fix one end of the tower to foundation plate. Bolt only one screw as the tower needs to still bend onto the ground, where we simultaneously fix the power box.
- Assembling the upper part - The upper part consists of clamps fixed with antennae installed onto 1 m pipe resting on the 6 m pipe. Before inserting 1 m pipe into 6 m pipe, we should put the triangle plate with rings around, that holds guy wire, should placed.
- Now, we have 6 m pipe sitting on foundation stool with one screw bolted. Power box containing power connections and Ethernet hubs is fixed in the middle of the tower. And 1 m pipe fixed with clamps and antennae is fixed onto 6 m pipe with triangle plate in middle. From here, we first need to raise the tower and tie two guy wires from top of the tower to L-shape hooks fixed on the ground using bull dog buckles. The third guy wire should be fixed with the help of turn-buckle to sufficiently tighten the rope to help the tower stand straight.