Characterization of Integrated Transmission Lines for RF Bandpass S? Modulators

Inhalt:
The specifications of microstrip (MS), coplanar waveguide (CPW) and various tapered transmission lines (TLs) intended for an integrated RF TL based σ δ modulator (ITLSDM) are discussed. The EM simulator Sonnet is used to achieve accurate models for TLs in a 0.25um BiCMOS technology. The physical parameters of different TLs are compared in order to achieve the guidelines, which ends up to a saved area and power consumption in the modulator. The equations for an area efficient meandering is given, which shows the area-quality factor trade-off. The results are supported with theoretical facts and verified with a resonator employed in a 4th order fs/4 bandpass SDM tuned at a center frequency of 2.5 GHz. Index Terms -integrated transmission line (ITL), sigmadelta modulator (SDM), resonator.