A 9 GHz silicon monolithic integrated TR switching circuit

A silicon monolithic integrated antenna TR switching circuit has been developed for operation at 9 GHz as part of a program for the investigation of Molecular Electronics for Radar Applications (MERA). The circuit is on a silicon chip 10 mils thick and 100 mils square. It consists of a microwave microstrip transmission line containing surface oriented diodes which alternately switch a transmitted or received signal to or from an antenna leg. Bias is supplied to the switching diodes through quarter wavelength meander line chokes which are by-passed to ground by thin film capacitors. The diode structures provide greater than 25 db of isolation between the receive leg and the transmit leg at 9 GHz. A typical reverse bias capacitance for these diodes is 0.008 pF.