Mobile telecommunication, mobile telecom, mobile communications, and cellular communications are some of the terminologies used for referring to the communication that occurs through our smartphones when connected to a mobile network. However, it is good to note that not all communication through our smartphones is mobile communication. There are, of course, cases when we are connected to a fixed WiFi network and use our smartphones as internet-enabled device just like we use our laptops. So what exactly does it mean to be connected to a mobile network? In simple terms, it just means that you are getting mobile signals on your phone from a nearby cellular tower, and the communication is taking place by your mobile phone communicating with that cellular tower. Below is what a cellular tower looks like. These towers are everywhere and without a nationwide deployment of such towers, you won’t be able to connect to a mobile network. Now that we have this view, let’s summarise our definition of mobile communications:
Mobile communication is a type of wireless communication that uses a large number of cells distributed throughout various geographical locations to provide connectivity to mobile and stationary users. Electromagnetic radiations from cellular towers create these cells.
Which type of communication is employed by mobile networks?
Mobile phones communicate with mobile networks through a range of cellular technologies. Many technologies have become part of the cellular industry since the first generation of mobile networks in the early 1980s. Following the first generation, 1G, we have seen a new generation of mobile networks nearly every ten years. Each generation is more advanced than its predecessor and uses a more sophisticated set of technologies to maximise the achievable bandwidth so that customers can do a lot more from their connection. To give you an example, back in the 1990s, when GSM was the main technology for 2G in most parts of the world, a channel bandwidth of 200KHz could enable phone calls and text messages. Nowadays, when we expect our phones to be connected to high-speed internet all the time, current technologies like 4G and 5G can enable bandwidths of 100 MHz and more through technologies like carrier aggregation.
How does a cellular network work?
A mobile network is a telecom network that emits radio waves at specific frequencies to create nationwide wireless coverage. Mobile devices such as smartphones also emit radio waves to communicate back with the network. The mobile phone and the mobile network are both able to transmit and receive using cellular technologies that we generally refer to as 2G, 3G, 4G and 5G.
In mobile communications, a cell is the network coverage area created by the transmission and reception of radio signals from a mobile base station. The place where a mobile base station is installed is called a cell site. Mobile operators use a large number of cell sites to enable nationwide coverage so that their customers stay connected no matter where they are. The emission of signals from the antennas of the radio units at the cell site creates cellular coverage. The radio units require electrical power to be able to generate electromagnetic waves that form cells of various sizes. The size or range of a cell depends on the radio unit’s frequency and transmission power. Higher frequencies have higher losses and do not travel as far as the lower frequencies can. The transmission power also determines how far a signal can travel. The radio signals are sent at specific frequencies so that they don’t interfere with the signals coming from other base stations. Only the intended mobile phone can decode the signal sent by the radio units at the cell site. The type of radio signal depends on which technology the mobile network is using for communication. Examples of the technology we refer to here are GSM, CDMA2000, LTE, etc.
What does a cell look like in cellular networks?
In any technical documentation about mobile networks, you will see small hexagons that the technical authors draw to represent cells. In real life, a cell’s shape is irregular and changes considerably depending on the terrain structure and obstructions like tall buildings, trees and mountains, etc. We have a simplified diagram below where the green, yellow and magenta icons represent cellular towers (base stations), and the hexagons represent cells created by the base stations. Each base station has several radio units that operate at specific frequencies to create radiations. These radiations create cellular coverage. Usually, each base station has multiple cells known as sectors of a base station, as you can see in the diagram below.
Cells do have a certain level of overlap with each other to allow some time for the handover to take place when someone is moving from one cell to another. A regular cell is known as a macrocell, and its range can be in tens of kilometres. There are different kinds of cells though including microcells and other smaller cells. The base stations are part of the mobile radio network.
What is the main reason for using cellular systems?
If someone has to choose between wireless and wired, the choice may be obvious. At the start of the digital era of mobile communications in the early 90s, mobile networks were good for voice calls and text messages, making them a wireless alternative to fixed telephones. However, with the capacity they could offer at the time, with GPRS and EDGE networks in the late 1990s, they were not well-positioned to provide high-speed internet services. With the advancements in 3G (e.g. HSPA) and with the launch of 4G, cellular networks positioned themselves as fully capable of addressing customers’ internet needs. So they were no longer just the alternative to fixed telephone but also fixed broadband. With 5G, the capabilities are even greater, and the cellular networks will play a key role in digitising many industries such as manufacturing, healthcare, etc. As mobile networks do not rely on cables running to every house, they are much quicker to deploy and with the technology constantly evolving; they are a solid player in fulfilling our home broadband and digitations needs.
Here are some helpful downloads
Thank you for reading this post, I hope it helped you in developing a better understanding of cellular networks. But sometimes, we need some extra support especially when preparing for a new job, or studying a new topic, or maybe just buying a new phone. Whatever you are trying to do, here are some downloads that can help you:
Students & fresh graduates: If you are just starting, the complexity of the cellular industry can be a bit overwhelming. But don’t worry, I have created this FREE ebook so you can familiarise yourself with the basics like 3G, 4G etc. As a next step, check out the latest edition of the same ebook with more details on 4G & 5G networks with diagrams. You can then read Mobile Networks Made Easy which explains the network nodes e.g. BTS, MSC, GGSN etc.
Professionals: If you are an experienced professional but new to mobile communications, it may seem hard to compete with someone who has a decade of experience in the cellular industry. But not everyone who works in this industry is always up to date on the bigger picture and challenges given how quickly the industry evolves. The bigger picture comes from experience which is why I’ve carefully put together a few slides to get you started in no time. So if work in sales, marketing, product, project or any other area of business where you need a high-level view, Introduction to Mobile Communications can give you a quick start. Also, here are some templates to help you prepare your own slides on product overview and product roadmap.