We encounter 5G in our everyday lives—whether it be when we scroll on our phones and brain rot or do productive work, it stays as a little icon on the top right corner of screens. But what exactly is it scientifically? And how does it work?
5G stands for the fifth generation of cellular network technology. In comparison to its predecessors—1G through 4G—it improves in three major aspects: faster data speeds, lower latency, and higher connection capacity. Behind these advancements are a whole world of electrical engineering, a field that works with electricity, electronics, and electromagnetic waves to build real systems such as tiny microchips and massive power grids.
Faster data speeds are one of the most visible improvements introduced by 5G. At its core, the transferred wireless signals rely on and are carried by radio waves. Like visible light, radio waves travel at the speed of light in a vacuum but are comparably much less defined, characterized by their lower frequencies and longer wavelengths [1, 2]. Wavelength is the distance between successive waves, while frequency is the number of wave cycles per second, typically measured in hertz. Wavelength and frequency have an inverse relationship: higher-frequency waves have shorter wavelengths, while lower-frequency waves have longer wavelengths.
With these basic concepts in mind, let’s consider two factors that are key to electrical engineers in building 5G: coverage and data carriage. Short wavelengths cause the wave to be more easily absorbed, scattered, and blocked as they interact more intensely with atoms and molecules encountered. Therefore, low frequency waves correspond to larger coverage, and high frequency waves correspond to smaller coverage. However, high-frequency also means greater data carriage or higher bandwidth [3]. As the waves oscillate faster with increased frequency, more signal changes (or number of cycles) occur every second, which translates to more bits (0s and 1s) of information being packed into the given time frame. In balancing these two factors to achieve high speeds, 5G uses a wider spectrum of radio waves, including higher frequencies that were not utilized in earlier generations, and carefully modeled wave behavior in real life to design a robust 5G network [3].
High capacity allows many devices to be connected simultaneously to the network. As the number of smart devices grew, earlier generations struggled in this aspect. 5G electrical engineers addressed this challenge by introducing the Massive Multiple-Input Multiple-Output (MIMO) [4]. In previous generations, each base station used only a few antennas to transmit and receive data [4]. Massive MIMO, on the other hand, packs dozens, and sometimes hundreds, of tiny antennas into a single unit, transmitting multiple data streams in parallel for different users [4]. As the result, speed, capacity, and efficiency were boosted significantly.
Latency refers to the delay between sending and receiving information, and 5G greatly reduced it. In addition to scaling up the number of antennas in Massive MIMO, a signal processing algorithm called beamforming is also incorporated [5]. Instead of blasting wireless signals everywhere, the base stations precisely control the phase and timing of the signals across each antenna, creating a narrow beam aimed at one user [5]. Different directed beams can be formed for different users simultaneously—thanks to the increased number of antennas—reducing interference, improving signal quality, and ensuring data packets arrive more quickly [5]. Low latency is especially important for uses that require real-time feedback, such as video calls and remote control systems.
5G heavily relies on other advanced electronics and circuits as well, and we will introduce a few here. In every 5G phone and base station, integrated circuits, commonly known as chips, do heavy computing [6]. Electrical engineers design these to be compact, energy-efficient, and fast at handling huge amounts of data with little delay. Each device also has Printed Circuit Boards that connect all the chips and electronic components. 5G uses specialized, low-loss materials and a well-thought layout to keep the signals clean and strong and facilitate heat dissipation [7]. Electrical engineers are very careful with power distribution and heat control inside the device to maximize battery life.
5G, as we can now see, depends heavily on electrical engineering for its design, implementation, and functionality. In addition to the daily benefits of more efficient networks and sustainable advancements, 5G networks have also enabled new, transformative applications such as remote surgery and autonomous vehicles, and made simultaneous breakthroughs in fields including healthcare and computer science [8]. It isn’t just a number switch from 4 to 5, but a vast scientific project requiring innovations at every layer.