X-Band Ultra-miniaturized 3-D Meander Delay Line Based on Substrate Integrated Coaxial Line

An ultra-miniaturized 3-D meander delay line based on Substrate Integrated Coaxial Line (SICL) is proposed in this report. Miniaturized circuit size is realized by a quasi-coaxial vertical transition structure between layers. The overall dimension is 4.505 × 2.54 × 0.902mm ³ . Key performance indicators are analyzed by the full-wave electromagnetic simulation environment High-Frequency Structure Simulation (HFSS). In X-band, the simulated S-parameters demonstrated that the overall return loss was less than -21.5dB and insertion loss better than -4.25dB. The delay line realized 0.83ns for 8λg delay range. A 3-bit switched delay line module is also designed.