Design of a new K-band push-push oscillator improving output power

As the modern communication technologies have been developed enormously, the higher frequency signals are required for transmitting the larger amount of information. The push-push structure for designing oscillator is one of the many techniques, which is used for increasing the oscillation frequency. Basically, the push-push oscillator circuit configuration enhances the even mode harmonics, and suppresses the odd mode output signal. Therefore, it doubles the oscillating frequency so that higher oscillating frequencies can be obtained beyond the limitation caused by the cut-off frequency of an available three terminal active devices [1-2]. The dielectric resonator is widely used for these applications since it shows the high quality factor [3]. However, it has a three dimensional (3D) structure, and its size is bulky. Therefore, it is not suited for the MMIC and it is hard to implement the small-sized circuit. To overcome this problem, hairpin resonators with a planar structure have been suggested and developed in MMIC technologies [4-5]. To improve the output power of an oscillator, the push-push oscillator is implemented on the harmonic oscillator type transforming the conventional push-push oscillator. Since each oscillator is designed as a second harmonic oscillator, the output power and the suppression of the fundamental frequency component are improved.