Xiantai Wang

An InGaAs/InP 40 GHz CML static frequency divider

Static frequency dividers are widely used as a circuit performance benchmark or figure-of-merit indicator to gauge a particular device technologys ability to implement high speed digital and integrated high performance mixed-signal circuits. We report a 2 : 1 static frequency divider in InGaAs/InP heterojunction bipolar transistor technology. This is the first InP based digital integrated circuit ever reported on the mainland of China. The divider is implemented in differential current mode logic (CML) with 30 transistors. The circuit operated at a peak clock frequency of 40 GHz and dissipated 650 mW from a single −5 V supply.

A 79 GHz sub-harmonic mixer design using a 1 um InP DHBT technology

This paper presents a 79 GHz sub-harmonic mixer (SHM) design based on a self-developed 1 um InP DHBT process. In this design, a low frequency local oscillator (LO) input signal at 39.5 GHz is doubled to W-band and a radio frequency (RF) signal ranging from 80 GHz to 86 GHz is down-converted to the intermediate frequency (IF) band with a best conversion gain around 1 dB at 83 GHz. As the knowledge of authors, it is the first attempt to implement an InP DHBT based SHM with a LO doubler in W-band. Due to lacking of available RF sources, the testing is realized with one port of an output power fixed Vector Network Analyzer enhanced by a frequency up-conversion module.

A W-band two-stage cascode amplifier with gain of 25.7 dB

A W-band two-stage amplifier MMIC has been developed using a fully passivated 2 ? 20 ?m gate-width and 0.15 ?m gate-length InP-based high electron mobility transistor (HEMT) technology. The two-stage amplifier has been realized in combination with a coplanar waveguide technique and cascode topology, thus leading to a compact chip-size of 1.85 ? 0.932 mm2 and an excellent small-signal gain of 25.7 dB at 106 GHz. Additionally, an inter-digital coupling capacitor blocks low-frequency signal, thereby enhancing the stability of the amplifier. The successful design of the two-stage amplifier MMIC indicates that InP HEMT technology has a great potential for W-band applications.

A W-band two-stage cascode amplifier with small-signal gain of 25.7 dB

A W-band two-stage amplifier MMIC has been developed using a InP-based high electron mobility transistor (HEMT) technology. The two-stage amplifier has been realized in combination with coplanar waveguide topology and cascode transistors, thus leading to a compact chip-size of 1.85 mm×0.932 mm and an excellent small-signal gain of 25.7 dB at 106 GHz. The successful design of the two-stage amplifier MMIC indicates the InP HEMT technology has a great potential for W-band applications.

A W-Band single-ended downconversion/upconversion gate mixer in InP HEMT technology

This paper presents an initial design of a single-ended gate mixer in self-developed InP High Electron Mobility Transistor (HEMT) technology and its critical parameters measured from 75 GHz to 110 GHz. This mixer realizes a fair conversion loss between 8 dB to 14 dB in full W-Band both in up and down conversion mode, and a 1-dB input compression points more than 0 dBm with the LO pumped at 89 GHz or 94 GHz. All measurement results above are illustrated and analyzed briefly. In a conclusion, it demonstrates the potentials and possibilities to develop passive mixers in W-Band with this process in more complicated structures.