Till the end of December 2010,several types of oscillators and frequency dividers have been developed successfully in Microwave Devices and Integrated Circuits Department (4th Department) of IMECAS with unremitting efforts.
Injection locked oscillator for K-band、Voltage-Controlled Oscillator for Ka-band
15GHz-injection locked oscillator for K-band was developed successfully in 4th Department of IMECAS in 1um GaAs HBT technology.The oscillator core locks at 15GHz by using the harmonic of injected signal.Fig.1 is the photo of the oscillator.The circuit can be locked by 2nd-20th even harmonic according to the test results,and can achieve lock for 15GHz oscillator by using at least 750MHz signal.This oscillator can conveniently actualize phase-lock for K-band, which can be used in the frequency source for this wave band.

Fig.1 15GHz-injection locked oscillator for K-band

At the same time, a kind of voltage-controlled oscillator for Ka-band has got successfully developed in 1um GaAs HBT technology.Fig.2 is the photo of circuit and spectrum analysis.

Fig.2 voltage-controlled oscillator for Ka-band and the spectrum analysis

DC~40GHz Frequency Divider
A new type of 1/4-frequency divider chip has been developed successfully by the HBT group of 4th Department.The chip can realize quadruplicate frequency division for DC~17GHz input frequency.The chip constructed of 2 levels of 1/2-frequency dividers,which are made up of ECL logic gates,and can divide the input frequency to DC~4.25GHz.This wave band is already within the rangeability of commercial phase-locked loop (PLL) chip.Being a kind of front-end chip for phase locked loop within 17GHz,this frequency divider has a very wide application.

Fig.3 DC-17GHz frequency divider and the spectrum analysis for quadruplicate frequency division

A type of 1/2-frequency divider circuit based on InP DHBT technics has also been developed successfully in 4 inch mini-fab for compound semiconductor devices and circuits, by the HBT group of 4th Department.

Fig.4 the photo of InP DHBT-based 1/2-frequency divider chip and the spectrum analysis

Being the frequency divider circuit with the highest speed in the nation,the frequency divider is composed of InP DHBT-based transistors whose fmax(maximum oscillation frequency) is above 300GHz. By combining GaAs-based 1/4-frequency divider and the InP-based 1/2-frequency divider,the PLL loop circuit can cover the frequency range of DC~40GHz.These 2 types of frequency dividers are the key components for milimeter-wave frequency sources.