In this paper, we present a low cost RF oscillator design incorporating a folded parallel coupled resonator. The oscillator is designed on FR4 substrate to achieve low cost. FR4 is a low cost substrate but has a poorly controlled dielectric constant and high loss tangent thereby challenging the design of higher performance circuits. This oscillator operates in 900 MHz band, delivers an output of -3.13 dBm and has phase noise 101.8 dBc/Hz at 10 kHz offset. The size of the folded parallel coupled resonator is 16% smaller than the conventional parallel coupled resonator, thereby making the overall circuit more compact. The power output and phase noise results are better than the oscillator designed with conventional resonator. Open loop analysis method has been adopted for the oscillator design and analysis. The measured data shows good agreement with the simulated results. The performance parameters of this oscillator make it suitable for use in low cost wireless communication solutions in 900 MHz band.
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