The Telecom Regulatory Authority of India (TRAI) wants the government to adopt the Tera Hertz Experimental Authorisation (THEA). This program is intended to accelerate the development of the Tera Hertz frequency band, which has specific characteristics that could make it indispensable for future wireless communication technologies, such as 6G.
Unique Properties of Tera Hertz Frequency
Tera Hertz waves also known as submillimeter radiation fall in a very interesting domain of the electromagnetic spectrum. Tera Hertz radiation lies roughly in the range between 0.1 THz and 10 THz, and the respective wavelengths range from 3mm up to 30 μm. Similar to other waves in the electromagnetic spectrum in the microwave range, terahertz waves are non-invasive and non-ionizing to biological tissues. Tera Hertz radiation can propagate through different nonmetal materials such as clothes, paper, wood, and ceramics. However, the penetration depth of radio waves is usually less than that of microwaves.
Tera Hertz waves have much less penetration power since they are severely damped by the atmospheric gases thus not suitable for long-distance terrestrial communication. They can, however, interact with thin layers of materials and deliver improved image resolution. Tera Hertz radiation is situated on the border of microwave and far infrared which makes it useful in material characterization and imaging that cannot be done by conventional techniques. Its peculiarities make it an attractive field worth investing in research and development.
THEA Program and Wireless Innovation
TRAI calls on the Indian government to initiate THEA, a strategic effort that aims at developing Tera Hertz. Consequently, the Tera Hertz band holds versatile characteristics appropriate to be part of 6G systems and future networks. Such possibilities could be opened with THEA, ranging from ultra-high-speed internet and various IoT applications.
Atmospheric absorption of terahertz radiation
Tera Hertz radiation is extensively absorbed by the gases in the Earth’s atmosphere of which water vapor and oxygen are the most constant. Hence, when energy is transmitted through air, then most of the energy is dissipated at a distance of a few meters. Because of such strong absorption, Tera Hertz waves are not feasible for long-distance terrestrial radio communication. Their efficacy drops considerably if used at longer ranges.
Tera Hertz waves can easily pass through thin objects like clothes, papers, cardboard, wood, and ceramics since they cannot pass through obstructions that are thicker. However, despite these limitations, Tera Hertz radiation has been utilized in material characterization, layer inspection, and relief measurement. It also can be used in place of X-rays to create detailed images of the interiors of solid objects with considerably less energy. Tera Hertz waves on the other hand hold great perspective, but unfortunately, they get absorbed by the atmosphere hence limiting their application in long-distance transmission.
Challenges in implementing Tera Hertz technology
Free space loss is one of the main problems that affect terahertz waves, greatly reducing their transmission range and communication distances. Another drawback of terahertz technology is its high cost of use and implementation. The efficient usage of this technology is still a matter of challenge due to poor source and detector developments. THz antennas have high loss rates and low manufacturing precision due to their size in higher frequency ranges. Some terahertz sources are bulky and expensive since they use unattainable materials in their construction.
Conclusion
India is known for its commitment to newer technologies and thus, it is in a perfect geographical location to unlock the full capabilities of THEA to revolutionize the wireless sector. In moving forward, THEA implementation can open the future of a faster and more interconnected traffic stream.
