# Revolution or Evolution? Technical Requirements and Considerations towards 6G Mobile Communications
## 2 Evolution of Mobile Communication
Users of 5G can expect tremendous improvements, such as a data transfer rate of up to 10 Gbps, significantly lower latency (at almost 10 ms) at a higher capacity, reliability, and QoS [22; 23]. The features of 5G have truly set this advanced mobile network apart from its predecessors. Unlike its predecessors, 5G is the first to utilize the mmWave band, a new technology of frequency band. Besides that, 5G is the focal infrastructure of IoT and is capable of integrating numerous new technologies, such as device-to-device (D2D) communication, software-defined networking (SDN), and massive multiple-input multiple-output (mMIMO) [24; 25; 26; 27]. The 5G signifies the revolutionary development of communication networks. Using a single platform, 5G offers various services, from advanced mobile broadband communications, automated driving, and VR to the IoT. With the recent decade's rapid technological advancements and innovations, going beyond 5G to satisfy the growing technological needs and demands at all levels is inevitable. The year 2030 is primarily targeted to be the year of launching the first commercializing system for 6G technology. A global digital society that is highly driven by highly advanced and almost instantaneous wireless connectivity by 2030 is envisioned [28; 29]. For this, 6G will play a central role in integrating seamless wireless connectivity and various technology functions (e.g., caching, communication, computing, control, imaging, navigation, positioning, radar, and sensing) that support full-vertical applications. Basically, 6G is a self-governing machine that can imitate human intelligence and consciousness and offers various means of communication and interaction with smart terminals (e.g., through brainwaves or neural signals, eyes, fingers, and voice). As a vision for the future, and due to 6G potentially utilizing a very high spectrum as compared to previous generations [30], 6G will dramatically improve the data rate speed, up to 100-1000 times faster than 5G [5]. Therefore, hundreds of Gbps to Tbps links will be available in 6G networks using the multi-band high-spread spectrum [31]. For instance, the combination uses 1-3 GHz band, 30-300 GHz band in mmWave, and 0.06-10 THz band in THz. Moreover, in terms of capacity, 6G aims to sharply increase the capacity by up to 1000 times more than 5G. For example, upper trillion-level objects will be connected to 6G, whereas billion-level mobile devices connect to 5G. Also, in terms of latency, 6G will provide latency up to 10-100 \(\upmu\)s. In other words, the evolution of the mobile communication networks from 2G to 5G was centered on servicing people, which means the latency depended on human reaction times, such as the visual reaction time (\(\sim\)10 ms), the auditory reaction time (\(\sim\)100 ms), and the perceptual response time (\(\sim\)1 ms) [3]. Sixth generation is expected to significantly change wireless evolution from connected things to connected intelligence. Furthermore, 6G is required to support ubiquitous AI services from the network's core to the end devices [10]. In other words, AI will be an essential factor in designing and optimizing protocols, the architectures, and the operation of 6G [9; 32].