Reseach And Design Of Millimeter-wave Phase Shifter Based On CMOS Technology

With the development of the society, the demand of wireless communication systems which have massive wireless data traffic and large access capacity are more and more stronger. However,by the restriction of the scarce spectrum and limited channel resources,the existing wireless communication standard s are hard to meet these requirements. Millimeter wave communication system based on phased array structure is a potential technology solution to handle these challenges, what is more,the extraordinary progress of silicon-based CMOS technology make the inexpensive monolithic integration phased array system which also has low power consumption is possible. As one of the key building block in phased array system, phase shifter is crucial. The main purpose of this paper is to research how to design a high precision and low power millimeter wave phase shifter of in CMOS process.The high insertion loss of silicon process seriously limits the performance of RF phase shifters, so an active structure based on vector s umming technique is adopted in this design to overcome this limitation and improve the signal gain of the circuit. The whole circuit is divided into three function blocks, including a variable gain unit, a orthogonal signal generator and a signal synthesizer. In order to reduce the area and power consumption, this design is improved on the traditional structure instead of a fully differential circuit. The variable gain unit, in the first stage of the circuit, change the amplitude of two in-phase signal in disperse states under the control of logic signal. The orthogonal signal generator is composed of inductance capacitance high and low pass network with the advantage o f wide frequency band and low loss. The signal synthesizer, composed of two Gilbert-cell circuits, includes two stages. O ne part is common-source amplifier, in order to compensate the loss of passive orthogonal network.The other one adds the signals with proper polarities under the control logic. In addition, the balun based current-reuse technique is applied to further reduce power consumption and chip aera.The 60 GHz active phase shifter is designed in TSMC 90 nm RFCMOS process.The measured results shows that the phase shifter can achieve 4-bit phase variation over 360 o. For all 16 states, the RMS gain error is 0.75~1.6 d B, RMS phase error ranges from 2.3° to 7.6° and noise finger is 9~12dB in the frequency regime from 57 to 64 GHz. The peak power gain is about 2.5dB at 60.5GHz, the chip area is 0.61mm2, the DC power is 19.8mW under the supply voltage of 1.8V.