Mobile Communication

Mobility communication is the collective term for technologies that enable users to communicate via wireless networks regardless of their geographic location. This evolution began in the 1980s with first-generation (1G) technology, which enabled analog voice transmission, and has since introduced innovations in speed, capacity, and reliability with each new generation. The fourth-generation (4G) mobile communication technology introduced in the 2010s standardized the mobile internet experience by popularizing applications such as HD (High Definition) video streaming and cloud-based services. Today, fifth-generation (5G) technology is ushering in a new era by offering ultra-high speed, extremely low latency, and high connection capacity, aiming to connect not only people but also billions of devices. 5G is forming the foundational infrastructure for future technologies such as the Internet of Things (IoT), autonomous vehicles, smart cities, and virtual reality.

Evolution of Mobile Communication Technologies

The development of mobile communication technologies has progressed through distinct stages known as generations. Each generation built upon significant technological advancements over its predecessor, opening the door to new services and capabilities.

1G (First Generation)

1G, emerging in the 1980s, was the first mobile communication standard, using analog signals to provide only voice call functionality. Although extremely limited by today’s standards, it laid the foundational concept of the mobile phone.

2G (Second Generation)

2G, transitioning to digital signals in the 1990s, improved voice quality and enabled Short Message Service (SMS) and later, low-speed data transmission via GPRS (General Packet Radio Service). This era facilitated the widespread adoption of mobile communication and paved the way for devices that would become the precursors to smartphones.

3G (Third Generation)

3G, introduced in the early 2000s, enabled the birth of mobile internet by offering significantly higher data speeds. Services such as smartphone proliferation, video calling, mobile applications, and online gaming became possible with 3G.

4G (Fourth Generation)

4G and its advanced variant LTE (Long-Term Evolution), deployed in the 2010s, made high-speed mobile broadband internet an indispensable part of daily life by providing capabilities such as high-resolution video streaming and fast file downloads.

5G (Fifth Generation)

The latest global standard, 5G, goes beyond being a mere continuation of previous generations; it is designed as a technology focused on vertical sectors—industrial and societal applications. Like each new generation, 5G requires significant changes and additions to infrastructure.

4G (Fourth Generation) and LTE Technology

Fourth Generation (4G) is a mobile communication system developed to deliver high-speed broadband services over mobile phones, featuring a fully IP-based network architecture. This technology, which became widespread in the 2010s, revolutionized the mobile internet experience by offering approximately ten times higher internet speeds than 3G. The foundational standard of 4G is LTE (Long-Term Evolution), developed by 3GPP (3rd Generation Partnership Project) and recognized globally as the natural evolution of 2G and 3G systems.

The significant enhancement of the LTE standard, LTE-Advanced, has been officially recognized as 4G by the International Telecommunication Union (ITU) because it meets 4G requirements. The technology introduced in Türkiye on 1 April 2016 and commonly known in public discourse as 4.5G is based on the LTE-Advanced Pro standard. This technology has increased mobile internet speeds up to twelvefold, enabling seamless use of bandwidth-intensive applications such as HD video streaming, high-quality video calls, and cloud-based services. By the end of 2021, approximately 80.2 million of Türkiye’s more than 86 million mobile subscribers had begun using 4.5G services. To ensure the reliable delivery of 4.5G, fiber infrastructure investments have accelerated, with Türkiye’s total fiber length exceeding 471,000 kilometers.

5G (Fifth Generation): The Beginning of a New Era

5G is the fifth-generation global wireless communication standard that has initiated a new era in today’s communication ecosystem. Beyond simply offering faster mobile internet, it is designed to enable highly efficient connections between machines, objects, and devices, thereby making possible new industries and societal applications. The central focus of 5G is to serve diverse vertical sectors. To this end, 5G technology is built upon three primary use cases:

1. Enhanced Mobile Broadband (eMBB): This scenario focuses on delivering significantly higher data speeds to users. By enabling multi-Gbps data transfer rates, it makes bandwidth-intensive applications such as 4K/8K video streaming, virtual reality (VR), and augmented reality (AR) feasible.

2. Ultra-Reliable Low-Latency Communication (uRLLC): This scenario is designed for mission-critical applications requiring extremely low latency measured in milliseconds and exceptionally high reliability. Applications include autonomous vehicles, remote surgical operations, smart grids, and industrial automation systems.

3. Massive Machine-Type Communication (mMTC): This scenario aims to connect up to one million devices per square kilometer. With low power consumption and wide coverage, it supports smart cities, smart agriculture, wearable technologies, and the broader Internet of Things (IoT) ecosystem.

Key Differences Between 4G and 5G

5G is not merely an increase in speed compared to 4G; it involves fundamental differences in architecture and capabilities. The ITU has established the IMT-Advanced framework for 4G and the IMT-2020 framework for 5G. According to these frameworks, the key differences are as follows:

Speed

5G can theoretically achieve peak data rates of up to 20 Gbps, while 4G’s peak rate is approximately 1 Gbps. This means 5G is up to 20 times faster than 4G. In practice, this speed enables the download of a high-resolution film within seconds.

Latency

Latency is the time taken for a data packet to travel across the network and return. In 4G, this latency ranges between 50 and 150 milliseconds, whereas 5G aims to reduce it to under 1 millisecond. This 60 to 120-fold reduction is critical for uRLLC applications requiring real-time control.

Capacity and Connection Density

5G can support up to one million devices connected per square kilometer, far exceeding 4G’s capacity and forming the foundation of the mMTC scenario. This enables high-quality connectivity even in densely populated areas such as stadiums or concert venues.

Spectrum Efficiency

5G utilizes the existing frequency spectrum 3 times more efficiently than 4G, allowing more data to be transmitted within the same bandwidth.

5G Architecture and Enabling Technologies

A set of innovative technologies and architectural approaches enable the superior performance of 5G.

Core Network and Service-Based Architecture (SBA)

Unlike the rigid, node-based architecture of 4G, the 5G core network is built on a flexible software architecture called Service-Based Architecture (SBA). In this model, network functions (NFs) communicate with each other via standardized and open interfaces to dynamically deliver services. This structure allows operators to integrate products from different manufacturers and accelerate the development of new services.

Millimeter Wave (mmWave)

5G uses high-frequency bands between 30 and 300 GHz, previously unused for mobile communications. These frequencies offer very high bandwidth but have short ranges and are easily obstructed by physical barriers such as buildings.

Small Cells

To overcome the range limitations of mmWave, 5G networks consist of numerous small, low-power base stations—called small cells—placed at intervals of approximately 250 meters, instead of relying on large, high-power base stations as in 4G. This dense network structure increases both coverage and capacity.

Massive MIMO (Multiple Input Multiple Output)

Massive MIMO is an advanced version of MIMO technology that involves deploying hundreds of antennas at base stations. These antennas simultaneously transmit focused signals to multiple users, significantly improving spectrum efficiency and data rates.

Beamforming

This technology intelligently directs radio signals directly toward the user’s device rather than broadcasting them in all directions. This results in a stronger, more stable connection while reducing interference for other users.

Network Slicing

One of the most important innovations of 5G is network slicing, which allows multiple virtual and independent networks to be created on a single physical infrastructure. Each “slice” can be customized for specific applications or customers—for example, a high-speed slice for eMBB and a low-latency slice for uRLLC.

Transition to 4.5G and 5G in Türkiye

Türkiye achieved a significant leap in mobile internet speed with the transition to 4.5G technology on 1 April 2016. During this process, local production capacity in mobile communication technologies was also developed through national projects such as ULAK, a domestically produced base station. As of 2022, 1,750 ULAK base stations are actively in use.

Efforts to transition to 5G technology are ongoing. According to statements from the Ministry of Transport and Infrastructure, the 5G auction is scheduled for 2025, with the goal of making 5G services available to citizens by 2026. Operators are preparing for this transition by conducting 5G trials in specific locations such as Istanbul Airport and upgrading their infrastructure. To benefit from 5G services, users must have a 5G-compatible device; however, existing 4.5G-compatible SIM cards will remain compatible with 5G networks. Defense industry companies such as ASELSAN are also aiming to play a leading role in this transformation by developing domestic products and solutions for 5G core networks and radio access networks.