25.8 A 2.4GHz VCO with FOM of 190dBc/Hz at 10kHz-to-2MHz offset frequencies in 0.13μm CMOS using an ISF manipulation technique

For the last few decades, phase-noise (PN) improvement of VCOs has been an intriguing problem and remains as one of the challenges in transceiver design. PN in CMOS VCOs, especially close-in PN, greatly suffers from flicker noise. The flicker noise can even degrade the PN at higher offset frequencies (~1MHz). The close-in PN is important in many communication applications. For instance, IEEE 802.11a/b/g requires a very low PN at 10kHz offset frequency [1] and the PN performance at 100kHz is critical in cellular and Wi-Fi MIMO applications. In addition to the PN performance, oscillators with lower power consumption and smaller area are always on demand.