Coverage and Capacity Analysis of a WiFi Network

 TryEngineering Hands-on Activity

Wireless networking has continued to be a very interesting topic in today’s communications society, as it remains the basis for the research and development of emerging network technologies and applications. For most wireless technologies and applications, WiFi seems to be widely used because of its simplicity and flexibility. Thus, engaging younger students in a hands-on activity that helps them to understand the theory behind the WiFi technology is of much significance, as it will better allow them to appreciate the wireless technology that runs their video games at home, playground and in school.

Pragmatically, in recent times and even today, WiFi has become an intrinsic part of life as humans demand for high-performance connectivity. This requires that experts should have the digital and superior experience in designing WiFi networks that meet these demands. Such experience includes knowing the number of WiFi-enabled devices, i.e node and terminals, that can be supported simultaneously based on the available bandwidth and the number of WiFi radio interfaces. These are required to understand the performance analysis of WiFi coverage and capacity, as high latency and drop-offs are no longer acceptable. Understanding the relationship between coverage and capacity, thus becoming key in balancing both elements.

WiFi networks are based on the random-access technique where a station or mobile terminal grabs the shared medium with a probability; such technique determines the average system throughput performance as well as fairness between users. On the other hand, the coverage (i.e communication range) of an access point/base station determines the number of users that can contend for the WiFi channel anytime they have data to transmit. For the coverage analysis, when a mobile terminal is within the communication range of an access point, the terminal is connected via a physical link (wireless), and it is possible for such a terminal to be connected to multiple access points at the same time but does not imply the user can transmit simultaneously. On the other hand, for the capacity analysis, if an access point serves multiple mobile terminals in its coverage area, the system throughput of the access point degrades theoretically with respect to the number of connected terminals.

Hence, capacity and coverage are fundamental concepts in wireless networks that children and younger students (pre-university) should be exposed to, and such exposure should begin by teaching them how a network topology is formed and how the throughput/data rate of user traffic is calculated. For this reason, the hands-on activity focuses on creating a random network topology of WiFi access points and mobile terminals, defining the communication range for connectivity to understand coverage, and the use of the Shannon capacity theorem to model the maximum capacity of an access point with single-connected mobile terminal. The fundamental concepts will be clearly explained to students through the hands-on activity which involves the graphical simulation of a random network topology and the theoretical calculation of the average throughput. While this hands-on activity is targeted at students in the age ranges 11-13 years old and 14-18 years old, it will be more understood by high school students and those preparing for college and have some basic background in programming, that is, they can read and understand some simple lines of code.

Topic Areas

• Wireless
• Network

Age Range of Students

• 14-18 years