Cellular Network

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A cellular network is a radio network spread out over land in the form of cells, each of which has a base station permanently installed. Together, these cells offer broader geographic radio coverage. Therefore, even when the user equipment (UE), like a mobile phone, is moving through cells during transmission, communication is still possible.

In comparison to previous options, cellular networks provide subscribers with improved advantages like increased capacity, low battery consumption, a wider geographic coverage area, and less signal interference. The Global System for Mobile Communication, general packet radio service, 3GSM, and code division multiple access are all common cellular technologies.

To establish a call and mobility network by linking mobile phones to wide area networks, every base station is connected to the mobile switching center. In contrast, wireless network devices are utilized to access the internet.

Wi-Fi has a constrained range, whereas cellular networks depend on the availability of network ranges.

What is a Cellular Network?

A communication network that uses a wireless connection to connect end nodes is known as a cellular network or mobile network. The network is spread out over "cells" of land, which are each served by at least one fixed-location transceiver ( A device that can both transmit and receive communications, in particular, a combined radio transmitter and receiver ). These base stations give the cell network coverage, allowing it to transmit speech, data, and other kinds of information.  To prevent interference and assure service quality within each cell, a cell normally employs a separate set of frequencies from its neighbors.

These cells can be connected to offer radio coverage across a big geographic area. This makes it possible for a large number of portable transceivers (such as mobile phones, tablets, laptops, pagers, etc.) to communicate with each other as well as fixed transceivers and telephones throughout the network via base stations, even if some of the transceivers are moving through multiple cells at once while transmitting.

Most of the populated terrain on Earth has voice and data cellular networks installed by major telecommunications companies. This enables the public to switch telephone networks and open Internet access to be accessed by mobile phones and mobile computing devices. Private cellular networks can be utilized for research as well as for big businesses and fleets, like taxicab companies or local public safety dispatch.

Cellular Network Architecture

In essence, a cell phone is just a radio. While complicated, the radio is still a radio. We need to briefly review the history of cell phones to fully comprehend how they operate. The fundamental structure and infrastructure of the cellular network have not altered much since then. It consists of a set of areas that are split into cells and services and are linked to one another by a network of transceivers, controllers, switches, routers, and registers. The following list includes some of the important parts and how they function:

Cellular Network Architecture

  • Mobile Equipment(ME) - This term refers to the actual phone. The phone needs to be able to function on a cellular network. Older phones were only able to use one band. Modern smartphones have dual-band, triple-band, and even quad-band capabilities. A quad-band phone has the technological ability to function on any network in the world.

The International Mobile Equipment Identity(IMEI) number serves as a distinctive identifier for each phone. The manufacturer permanently imprints this number on the phone. Reading the panel in the phone's battery well after removing the battery typically yields the IMEI.

  • The antenna you see mounted on top of the tower is known as the Base Transceiver Station (BTS). The mobile phone's network access point is the BTS. It is in charge of managing radio communications between the mobile phone network. It manages the radio signal modulation and demodulation as well as voice encoding, encryption, and multiplexing. Typically, one BTS covers a single 120-degree sector of space. A tower with three BTSs will often be able to accommodate all 360 degrees surrounding the tower. However, a cell may be split into one or two sectors, or a cell may be served by numerous BTSs with redundant sector coverage, depending on the geography and user demand of an area. A Cell Identity is assigned to a BTS. A specific Location Area is indicated by the cell identification, which offers information about the cell that the BTS is covering.
  • A base station (transmitter) with several RF ( Radio Frequency ) channels is referred to as a cell. Within its borders, each cell only provides coverage for a certain number of mobile users (Coverage area). A cell radius is roughly 30 km at startup and 1 km at maturity.
  • Cell Size and Capacity - The number of cells needed to cover a certain area and, with frequent reusing, the total capacity made available to all users, depending on the cell size. The amount of bandwidth that is available and the needs of the operation limit cell capacity. Cells must be sized by each network operator to accommodate anticipated traffic demand.
  • Base Station Controller (BSC): The BSC is in charge of managing numerous BTSs. It manages frequency management, power and signal measurements from the MS, radio channel distribution, and handovers from one BTS to another (if both BTSs are controlled by the same BSC). Additionally, a BSC serves as a "funnel." As a result, there are fewer connections to the Mobile Switching Center (MSC), and more connections with greater capacity are made possible. A BSC may be physically close to a BTS, or it may be far away. Even so, it might share space with the Mobile Switching Center (MSC).
  • The GSM network's beating heart is the mobile switching center or MSC. It manages call setup, call routing, and fundamental switching operations. An MSC interacts with other MSCs, registers, and manages many BSCs. Additionally, it manages handoffs between BSCs and organizes inter-MSC handoffs with other MSCs.

Working on the Cellular Network

Mobile communications adhere to the basic telephony idea of connecting two remote customers via the network infrastructure of a service provider that is in charge of running the operation. However, unlike fixed phones, the ultimate connection in the mobile network does not consist of copper lines or fiber optics but rather radio broadcasts. A user's mobile phone connects over the air with a base station antenna, which is connected to the operator's computer-based central exchange. Using another base station or the fixed network directs the communication to the intended recipient.

A mobile user must be near base stations to communicate. This has a small coverage area surrounding it termed a "cell", which is why the alternative moniker "cellular networks" is sometimes used to refer to mobile networks. Operators deploy thousands of cells, each fitted with antennas, to cover the largest possible area and guarantee that users can always call. By ensuring that their cells overlap, they ensure that users' present locations are constantly known.

The number of base stations used, the kind of topography (plains, mountains, valleys, etc.), the installation location (rural or urban regions), and the population density are just a few of the variables that affect cell size. The mobile phone's range, which must be able to establish the return link, is another factor that restricts cell size. Furthermore, base stations can only support a specific number of simultaneous calls due to their restricted transmission capacity. Because of this, cells in metropolitan areas tend to be numerous and small, spaced hundreds or even just tens of meters apart, where there are many communications and a high population density. The cell size can reach up to several kilometers, but it seldom goes over 10 kilometers, in rural areas with significantly lower population densities. It is crucial to stress that lowering the base station signal's strength also lowers the coverage provided by the cells. Increasing the number of base stations is, therefore, a requirement for improving the network's capacity to transport voice calls or data traffic.

Types of Cellular Networks

Your mobile internet's speed can vary greatly. Remote places may not always have the same level of coverage as major cities since some countries have more sophisticated telecom networks than others. Even being inside can have a huge impact.

An alphanumeric code near the signal bar on your smartphone helps you know the quality of your mobile internet coverage. You'll understand what we're talking about if you've ever seen something on the notification bar with the letters E, 3G, or `H.


The letter G stands for General Packet Radio Service (or GPRS). The unofficial moniker 2.5G was given to it when it started to be widely utilized in 2000. It is regarded as the first significant step toward the creation of the 3G networks, which are currently commonplace.

Although it was the first mobile internet network that was "always on," its maximum data transfer speed of 114 kilobits per second makes it the slowest connection you're likely to find today.

Because of this pace, even though the network can support instant messaging services like WhatsApp, other, more complex apps and websites would most likely time out, glitch, or, at best, load very slowly.


The 2G technology, which was originally introduced in 1991, is what ultimately made it possible for data services like SMS and MMS to become widely used on mobile phones later in the decade.

Additionally, it marked the first instance in which radio signals were sent digitally rather than analogically (1G), resulting in higher spectrum efficiency and wider market penetration for mobile phones.

The 2G networks are currently being shut off in most of Europe and North America, and their top speed is bare 50 kilobits per second. Despite this, it continues to be the preferred network across a major portion of the developing globe.


For the GSM Evolution network (also known as EDGE), the letter E stands for enhanced data rates. Due to its nearly three times higher speeds than any of its predecessors, the network began to gain popularity around 2003.

Despite being substantially quicker than G network rates, its maximum speed is still 217 kilobits per second, thus you won't be able to watch YouTube videos in anything but the lowest resolutions or browse the web on a modern website.

Nonetheless, EDGE has become one of the most popular mobile internet technologies globally, with 604 networks currently operating in 213 nations. It's sometimes referred to as 2.75G because it was the last widely-used network before 3G became well-known.


Contrary to popular belief, 3G technology has been around for far longer. Japan built the first commercial network in October 2001, Norway followed in December 2001, and by early 2002, the majority of Europe and South East Asia were online. Verizon Wireless launched the country's first 3G network in July 2002.

Instead of any of its three predecessors, which are listed above, the 3G network is based on Universal Mobile Telecommunication Service (UMTS) standards (GSM, GPRS, and EDGE).

With a top speed of 384 kilobits per second, it's more than sufficient for streaming music and even some films. It was the first network fast enough to offer mobile internet browsing as we know it today. Due to its extensive use and the advancement of smartphones, it is most likely the most well-known of all mobile internet networks. Today, 3G technology is present in a wide range of devices, including mobile television and wireless voice telephones.


If you see an H sign, your connectivity is High-Speed Packet Access (HSPA). With a maximum speed of 7.2 Megabits per second, the HSPA standard replaces the UMTS standard used in 3G and is based on the same technology.

It can easily manage to stream Spotify music, web surfing, and other app activities. Although they would still take a very long time, it is not good enough to accommodate movie downloads or massive torrent files. Global adoption started in 2010, and the majority of wealthy nations now have access to it.


H+ stands for HSPA+ or evolved high-speed packet access. This technology has been released five times, and each one offers download rates that are noticeably faster than the one before it.

Maximum speed was 14.4 Megabits per second with Release 6, 21.1 Megabits per second with Release 7, 42.2 Megabits per second with Release 8, 84.4 Megabits per second with Release 9, and 168.8 Megabits per second with Release 10.

As you can see, technology advanced incredibly swiftly in this area, but it's crucial to keep in mind that typical usage rarely experiences speeds like this. Since worldwide 4G networks are still not widely available, this is the fastest form of connectivity that the majority of people can currently access.


In 2009, Stockholm and Oslo launched the first public 4G networks in the world. Over the ensuing years, more nations gradually joined them. In the UK, the nationwide rollout took place in 2014, whereas, in the US, the network is currently available in many of the biggest cities.

Though some of these networks, like Sprint in the US, employ the less popular Worldwide Interoperability for Microwave Access (WiMAX) standard, the majority of these networks use the Long Term Evolution (LTE) standard. By the end of 2017, the majority of carriers in Europe and North America had abandoned WiMAX.

The differences between the two are insignificant to the end user. WiMAX's major flaw is that not enough carriers used it to make it economically feasible, leaving LTE the de facto standard. Why did carriers decide not to deploy WiMAX?

  • WiMAX networks do not support 2G and 3G legacy systems, but LTE is interoperable, supports coexistence, and facilitates easier roaming.
  • Maximum speed is greater with LTE.
  • LTE uses less power from a phone's battery.
  • With 4G, speeds can reach 1 GB per second.


By the end of 2025, 5G is anticipated to be available to more than 1.7 billion people worldwide, having begun its global rollout in 2019.

The higher bandwidth of 5G over 4G is its main benefit. It is 100 times faster than the top speed of 4G and has a maximum potential speed of 10Gbps.

Even though 5G is currently only available on smartphones, it is believed that this technology could bring about a revolution in the way that we use the internet at home. As businesses develop ways to provide internet to homes without installing wires, traditional ISPs will face major threats.

The limited signal range of 5G is a drawback. Since 5G relies on high-frequency radio waves, the physical cells that support phones will be smaller, necessitating more towers and raising rollout costs. There will be a total of three frequency bands: a low-band (600-700MHz), a mid-band (2.5-3.7GHz), and a high-band (25-39GHz).

Features of Cellular Network Systems

Spectrum congestion is eliminated by wireless cellular systems, which also improves user capacity. The following are some characteristics of cellular systems:

  • Offers a small spectrum with extremely high capacity.
  • Radio channel reuse in many cells.
  • Reuse the channel over the whole service area to allow a fixed number of channels to serve an arbitrarily large number of customers.
  • Always in communication are the base station and the mobile device (not directly between mobiles).
  • Within a constrained region known as a cell, each cellular base station is given a set of radio channels.
  • Different channel groups are assigned to neighboring cells.
  • The channel groups can be utilized to cover more cells by limiting their coverage to the cell's perimeter.
  • Maintain interference levels at acceptable levels.
  • Frequency planning or frequency reuse.
  • Network setup for wireless cellular devices.

Advantages of the Cellular Network

The following are the advantages of a cellular network:

  • Voice and data services are offered by it.
  • Both fixed and mobile users can connect using it.
  • It has a bigger capacity.
  • The upkeep is simple.
  • The equipment can be easily upgraded.
  • Less power has been used.
  • It is utilized in locations where cables cannot be deployed because it is wireless.
  • It can utilize practically all public and private networks' capabilities and functionality because it is versatile enough.
  • It can be dispersed to areas with greater coverage.
  • The equipment is easy to upgrade, and both mobile and fixed subscribers are immediately linked to the cellular network when their phones are turned on.
  • It lessens signal interference from other sources.

Disadvantages of the Cellular Network :

The following are the disadvantages of cellular networks:

  • In comparison to wired networks like fiber optics and DSL, it offers a lower data rate. Based on wireless technologies like GSM, CDMA, LTE, etc., the data rate varies.
  • Multipath signal loss has an impact on macro cells.
  • The capacity is reduced and is reliant on the channels and various access methods used to serve subscribers.
  • The communication poses security flaws because it is wireless.
  • The infrastructure needed to put up a cellular network is more expensive.
  • Physical barriers, weather variables, and wireless device interference all affect wireless communication.
  • A foundation tower and space are needed for the installation of antennas for cellular networks. This is very time-consuming and labor-intensive.


  • As new requirements, technology, and solutions have emerged for each generation, cellular networks have undergone substantial evolution.
  • In the future, cellular networks will serve as the foundational connectivity platform for new applications such as Internet of Things (IoT) devices, robotics, virtual and augmented reality, and mobile gaming.
  • Due to its promise of faster speeds, lower latency, and the usage of previously untapped frequency bands, 5G is taking shape and ushering in new possibilities similar to the invention age.
  • The multiplexing and access strategies used by radio channels to effectively employ the transmission medium include frequency-division multiple access (FDMA), time-division multiple access (TDMA), code-division multiple access (CDMA), and space-division multiple access (SDMA).
  • The mobile phone provider uses a cellular network to provide subscribers with capacity as well as coverage. To prevent line-of-sight signal loss and support a high density of active phones, large geographic areas are divided into smaller cells. The public telephone network is connected to telephone exchanges (or switches), which in turn are connected to all of the cell sites.
  • Similar to a two-way radio system, mobile phones operate by transmitting and receiving low-strength radio signals. The signals are transmitted to and received by antennas that are fastened to radio transmitters and receivers, also known as base stations for mobile phones. The base stations transmit the signal or call into such networks since they are connected to the rest of the mobile and landline phone network.