Composite right/left handed artificial transmission line structures in CMOS for controlled insertion phase at 30 GHz

Two CMOS integrated circuits are presented that utilize metamaterial composite right/left handed (CRLH) transmission lines (TLs) for zero insertion phase at 30 GHz. Specifically, 2 and 3 unit cell structures are presented with controlled insertion phase that is achieved by cascading lumped element capacitors and spiral inductors in an LC network configuration defining the TL unit cells. Furthermore, the fixed TL structures suggest the possibility of zero, advanced or delayed insertion phases by element variation, or by the use of simple active components. Simulation and measured results are in good agreement with CRLH TL theory. and display a linear insertion phase and flat group delay values that are dependent on the number of unit cells with an insertion loss of similar to 0.8 dB per cell. These findings suggest that such high speed CRLH TLs structures can he implemented for linear array feeding networks and compact antenna designs in CMOS at millimeter wave frequencies. (C) 2008 Wiley Periodicals. Inc. Int J RF and Microwave CAE 19: 163-169 2009.