An LTCC Based Differential Microwave DRO Module

Low Temperature Co-fired Ceramic (LTCC) technology is a multi-layer ceramic process that is well suited to the realisation of low cost, high performance RF and microwave components. This paper describes the design, fabrication and evaluation of a 21.3GHz differential Dielectric Resonator Oscillator (DRO) module fabricated in LTCC. It has a measured output power of +3dBm and an amplitude imbalance between the output ports of < 0.2dB. The measured phase noise is –102dBc/Hz at 100kHz offset from carrier. The module was the prototype of a commercial product that is now under development. The commercial product will also include a small voltage tuning range to allow phase locking of the DRO for applications such as clock generation in 40Gb/s optical transceivers.