LG Uplus has started testing the Reconfigurable Intelligent Surface (RIS), which is considered a core technology for 6G mobile communications.
RIS is a programmable structure that can be used to control the propagation of electromagnetic (EM) waves by altering the electrical and magnetic properties of the surface. By placing smart surfaces in the environment where wireless systems operate, a telecommunications operator can at least partially control the properties of radio channels. It can be compared to an intelligent mirror which adjusts the transmission power according to the characteristics of the radio waves. 3GPP, a global mobile communications standards organization, is considering designating RIS as a standard 6G technology.
LG Uplus recently partnered with Nokia to test RIS in a mobile environment and labs. LG Uplus will test RIS in 5G 3.5GHz and 28GHz frequency bands, and when the 5G frequency verification is completed in 5G band, it plans to test it in terahertz band to verify the effectiveness of RIS for 6G communications.
6G services are expected to use the terahertz band, which has not been used for mobile communications. A major advantage of terahertz waves is that they have a large bandwidth, which makes it possible to increase the speed of data transmission to one terabit per second. However, their wavelength is very short, so the loss may increase when the waves encounter an obstacle or when transmitted indoors from an outdoor base station. Experts say that a RIS can cover the weakness of terahertz waves by adjusting the transmission power according to the characteristics of the radio waves.
Mobile operators and equipment manufacturers are also conducting research on SIFs with candidate 6G physical layer technology. In a 6G white paper, Samsung Electronics introduced measures to resolve areas of service interference using RIS. Japanese company NTT DoCoMo also announced measures to improve indoor coverage using SIFs.