Researchers at the National Astronomical Observatory of Japan have developed a new method, achieving 100-fold improved precision in insulator permittivity measurement.
Permittivity signifies the response of electrons within an insulator when subjected to a voltage. This value holds significance in comprehending radio wave behaviour through insulators. In the evolution of telecom equipment, precise permittivity assessment for materials in circuit boards and structures is vital. Radio astronomy likewise demands knowledge of component permittivity in radio receiver construction.
Researchers at the National Astronomical Observatory of Japan have invented a new technique, achieving 100-fold enhanced precision in insulator permittivity measurement. This advancement is poised to bolster the creation of high-sensitivity radio receivers for radio telescopes and aid the progression of “Beyond 5G/6G” devices for next-generation communication networks.
Creating an electromagnetic wave propagation calculation approach, the researchers have developed an analytical algorithm for precise permittivity determination, avoiding approximations. The team applied this novel method to assess the lens material in an Atacama Large Millimetre/submillimetre Array (ALMA) receiver under development. The technique is poised to impact radio telescope component design and the creation of high-frequency materials and devices pivotal for achieving next-gen communication networks. A 100-fold reduction in approximation-related errors accelerates the development pace significantly. Inaccurate measurement of individual material permittivity could lead to the final product falling short of the intended performance. Precise knowledge of permittivity from the design phase minimises trial and error and trimming costs.
Traditionally, multiple methods are employed for permittivity measurement. One accurate approach is the “resonance method,” requiring precise processing of materials, sometimes just a few hundred micrometres thick, to place within a resonator. A drawback is its limited applicability to specific frequencies. As various materials’ permittivity needs measuring during device development, relying on high-precision processing for each assessment elongates the development timeline. Conversely, the “free-space method” offers fewer constraints, yet it leans on approximations to analyse results, introducing errors that hinder precise measurement.
The team aims for further technological innovation, blending insights from astronomical instrument development with those from communication technology advancement.
Reference: Ryo Sakai et al, Accurate Free-Space Measurement of Complex Permittivity With the Angular Spectrum Method, IEEE Transactions on Terahertz Science and Technology (2023). DOI: 10.1109/TTHZ.2023.3272041
