Low Phase Noise Free-Running Oscillator Based on High Selectivity Bandpass Filter Using Composite Right/Left-Handed Transmission Line

This letter presents a novel low phase noise freerunning oscillator based on a high selectivity bandpass filter (BPF) using a composite right/left-handed transmission line (CRLH TL). The oscillator is designed at the spectrum-based quality factor (Qs) peak frequency to achieve low phase noise performance. Ata center frequency of 2.05 GHz, the oscillator demonstrates, experimentally, a phase noise of -150.4 dBc/Hz at 1 MHz frequency, offset with a figure of merit(FOM) of -207.2 dBc/Hz, less than -32 dBm spurious harmonics, and total oscillator power consumption of 6.1 mW from a 2 V supply voltage.