A wide locking range and low phase noise quadrature frequency synthesizer suitable for next generation wireless communication systems

This paper describes the design of a fully-integrated PLL-based and integer-N quadrature frequency synthesizer (QFS) for Ka, V and E multiband mm-wave applications. A 2-bit switched capacitor array directly controlled by voltage level together with MOS varactor and differential coplanar waveguide (CPW) inductors are used in the quadrature voltage-controlled oscillator (QVCO) to cover the wide frequency tuning range, achieve a good phase noise performance of -105.5dBc/Hz@1MHz offset while realizing a wide tuning range over than 19.26%. Multiband co-tuning (MBCT) technology is proposed to extend the frequency locking range of ILFD. A programmable charge pump is designed to obtain relatively constant bandwidth. The quadrature frequency synthesizer, implemented in IBM 0.13μm CMOS process, can provide over than +0.88dBm output power at 50ohm load from 27.72 to 33.63GHz while drawing 50mA current (not including testing buffers) from 2.5V power supply and 49mA from 1.2V power supply.