Here is the abstract you requested from the cicmt_2013 technical program page. This is the original abstract submitted by the author. Any changes to the technical content of the final manuscript published by IMAPS or the presentation that is given during the event is done by the author, not IMAPS.
|Nonlinear Transmission Lines Using Substrate Integrated Waveguides in LTCC|
|Keywords: Nonlinear Transmission Line, Ferroelectric, Substrate Integrated Waveguide|
|The generation and transmission of relatively short duration, broadband, peak pulse power bursts has numerous applications in the communications and defense sectors. In the past, nonlinear transmission lines (NLTLs) have been used to create such pulses with much higher peak power densities than direct synthesis from standard microelectronic devices would allow. While most NLTL designs are based on nonlinear capacitors or inductors arranged in a ladder network, the method presented here replaces the transmission line with a novel ferroelectric filled waveguide. When a large gap driven transient voltage is input to the guide the resulting electric field will cause the polarization field to move into the saturation region. This reduces the effective dielectric permittivity and thus the group velocity of the peak power portion of the wave is faster than all other portions of the pulse. This results in the middle portion of the pulse overtaking the leading edge and ‘piling up’ energy at the front edge of the pulse, creating what appears to be a temporal compression of the leading edge. The associated temporal compression results in increased peak power density and increased harmonic spectral content. The simulated NLTLs can be fabricated using Substrate Integrated Waveguides (SIW) in low temperature cofired ceramics (LTCC). The upper and lower waveguide walls are formed by printing of lateral metallization and the vertical side walls, end walls, and probe feed are created using via punch and metallization technique. Closely spaced vias form trenches in the waveguide that are used to create space for the nonlinear dielectric and the trenches are filled with ferroelectric materials using a sol-gel method. The trench width and type of ferroelectric fill material for each layer are determined using a genetic algorithm optimization routine that produces a maximum peak power enhancement and time compression of the input pulse.|
Auburn University, AL