Low loss LTCC passive transmission line at Millimeter-wave frequency

60 GHz band has advantages in terms of broadband, frequency reuse, dimension of circuit, size of layout, and power. A wide bandwidth available in 60 GHz band is ideal for the high data rate transmission. It is also advantage of 60 GHz band that the passive circuit can be made very small. Due to those advantages, this band now is applied to Millimeter-wave (MM-wave) video transmission, outdoor and indoor wireless system, wireless Gigabit Ethernet link, and 60 GHz wireless LAN application. A low temperature co-fired ceramic (LTCC) becomes a technology of choice when it comes to MM-wave band. However, LTCC shows several issues on integration of MM-wave circuits such as; attenuation, resonance and isolation of passive circuits. This paper described the design techniques for an efficient low loss LTCC passive transmission lines. LTCC passive transmission line was design in the 6-layers of LTCC dielectric substrate, using Advance System Design (ADS) and Computer Simulation Technology (CST) for EM simulation. Analysis and measurement of transmission lines using different substrate height of 100 μm and 114 μm was also presented. The proposed structure is validated by full-wave simulation, and experimental measurements. The analyses of fabricated modules with 100 μm and 114 μm shows the passive transmission lines achieved the insertion loss less than -1dB and return loss less than -10dB.