So many variables for long wi-fi communication
The question relating to distances and WI-FI communications is a complicated one because there are so many variables. There are very strict FCC rules which have to have complied with relation to the strength of the signal. Then there is the issue of the antenna used and whether it is flat terrain or not. In highly populated urban areas with many high buildings, things become even more uncertain because signals will bounce of buildings in all directions which will have a detrimental impact on the signal. Therefore, when moving into a specific area you need to analyze the surroundings and then design a system which will work adequately in that environment. Large cities can present many challenges to WI-FI technicians and to ensure adequate signal reception over a distance of a kilometer you may require several transmitting routers. Such a setup can become expensive and therefore many participants will be needed to make it viable. In order to ensure suitable long distance WI-FI, the services of technical experts will be required who will be able to weight hardware requirements against the challenges encountered in the chosen location.
It is generally best that WIFI is used locally and before installation proceeds, all possible interference problems must be solved. Radio waves’ behavior is similar to the way light behaves and just like the light, it can be blocked by solid objects. Radio signals can also be reflected but will travel in a straight line when they encounter free space. Over the years there have been many instances where WIFI communications over long distances have been achieved. In this regard, high mountain tops are very useful especially those situated in unpopulated areas. Even then, antennas have to be used which can optimize transmissions by concentrating the signals into beams. In practice, there can be many limiting factors but theoretically, a WIFI signal can reach very far but this requires a WI-FI sender that would be strong enough to reach your home. Some WIFI users think that a large reception dish will solve their problems but it is really the signal strength that is important. In most cases, WIFI signals are used over short ranges which consumes less power and most service providers will not attempt long distance WIFI because for that they have radio access towers.
A typical network
In most networks, low energy consumption devices such as sensors are used. These devices are then connected to gateways which are part of a larger communications network which will proceed to send data to other devices often network servers. Once received by servers, the data will be assessed and passed along to end devices as and when needed. This will require protocols which have been optimized for their long-range capabilities. However, these are low power devices in order to keep operating costs as low as possible. For many years wireless technologies such as cellular were in a favorable position when it comes to long-range applications because they were able to access the internet with their devices without the need for a gateway. There are now many excellent technologies utilized worldwide which allows communication between the cloud and SIM cards. All that is required is to register the SIM card with the network provider whereafter data can be received and sent.
So much progress
So many extraordinary technological advances have been seen over the last couple of decades. Even cellular applications have gone from modest transfer speeds to the LTE standards which supports transfer rates of almost 4gbps. Not all wireless technologies can do this and users must never forget the earlier mention of cost which increases because of the power consumption required to maintain high transfer speeds. The industry is looking at ways to communicate over long distances however using low power consumption so that cell batteries will last. Even though LTE has certain benefits it is costly because it requires licensed cellular wireless networks. There is also the issue of the end device which requires its own SIM card and this converts to additional installation which also causes increased maintenance costs. Sophisticated cellular technologies are definitely not cheap compared to other types of wireless technologies. As far as LTE is concerned it requires a complicated SIM card service but future technologies may solve these problems.
Other viable technologies
There is another excellent communications technology known as SigFox which in rural areas can be transmitted over distances of as much as 50 km while a favorable urban condition may allow distances of 10 km. It provides low data rates and relatively low power consumption. Using this technology requires end devices to be equipped with SigFox technology in order to allow those devices to communicate with SigFox base stations. From there the data is sent to SigFox cloud servers. At this point, all received data is processed before an answer is send to the end devices.