Recently, the center has made important progress in the research field of integrated microwave photonics. The research team has developed the world's first microwave photonic functional system with full chip-based optical-electrical integration using a hybrid optoelectronic integration technology solution, and experimentally demonstrated fast and accurate measurement of the instantaneous frequency of ultra-wide-band microwave signals. The results were published on August 12, 2022 in the journal Laser & Photonics Reviews under the title "Fully on-chip microwave photonic instantaneous frequency measurement system". Reviews.
Microwave photonics, as a cross-discipline integrating microwave radio frequency technology and optoelectronics, has important application prospects in the fields of next-generation communications, radar, sensing, aerospace, military and security. Among them, realizing the miniaturization, on-chip and integration of microwave photonics systems is one of the key bottlenecks to promote the real landing and wide application of microwave photonics technology. However, previous research efforts have failed to achieve full on-chip integration of microwave optical subsystems, and discrete optical devices (e.g., lasers, modulators, etc.) or electrical devices (e.g., electrical amplifiers, etc.) are required to build the complete system link. This constrains the practicality and popularization of microwave photonics technology in terms of cost, size, power consumption, and noise performance.
To solve the above problems, the research team proposed a hybrid integration scheme of multi-chip platforms integrating silicon-based optoelectronic (silicon-optical) chips, indium phosphide chips and CMOS electrochip. This solution overcomes the problem of insufficient integration integrity of the single material platforms used in the past, and realizes a fully integrated pull-through of the microwave photonic system link for the first time. In order to verify the feasibility of this multi-platform optoelectronic hybrid integration scheme, in this thesis the researchers used this scheme to design and implement an integrated microwave photonic instantaneous frequency measurement system. As shown in Fig. 1, the size of the system is about a few tens of mm2 and the power consumption is only 0.88 W.
Fig. 1 (a) Structural diagram of the integrated microwave photon transient frequency measurement system (b) Physical diagram of the indium phosphide laser chip and the silicon optical chip (c) Physical diagram of the integrated package of the overall system
The integrated microwave-optical subsystem is based on the operating principle of frequency-optical power mapping, which enables the measurement of the instantaneous frequency of microwave signals in an ultra-wide frequency band (2-34 GHz). As shown in Figure 2, for the electronic countermeasures, radar warning and other practical application scenarios, the researchers experimentally demonstrated the integrated microwave photonic system for the microsecond fast time-varying frequency hopping, linear FM, secondary FM and other different formats of microwave signals real-time frequency measurement. The frequency measurement error of 55-60 MHz is the best performance ever demonstrated by an integrated microwave photonic system of its type. The multi-platform optoelectronic hybrid integration process scheme proposed in this work is of high reference value for the study of the integration and miniaturization of various types of microwave optical subsystems, such as RF signal generation, signal processing, and signal transmission. This provides a versatile solution for advancing the engineering applications of microwave photonics.
Fig. 2 (a) Frequency hopping (FH) (b) Linear frequency modulation (LFM) (c) Secondary frequency modulation (SFM) signals with frequency dynamics measurements
The co-first authors of the paper are Yuan-Sheng Tao, a PhD student of the Center in the class of 2017, and Feng-He Yang, PhD, of the Yangtze River Delta Institute of Optoelectronics Science, Peking University, with Prof. Xingjun Wang as the corresponding author. The main collaborators include researcher Chang Lin from the School of Electronics, Peking University, as well as postdoctoral fellow Hao-Wen Shu, PhD students Zi-Han Tao and Ming Jin from the Center, and Yan Zhou and Zhangfeng Ge from the Yangtze River Delta Institute of Optoelectronic Science, Peking University. The above research was funded by the National Key Research and Development Program and the Beijing Natural Science Foundation. This work was completed by the State Key Laboratory of Regional Optical Fiber Communication Networks and New Optical Communication Systems, School of Electronics, Peking University, as the first unit, and is also an important result of the cooperation with Pengcheng Laboratory, which is one of the core contents of the major research tasks of the Circuits and Systems Department of Pengcheng Laboratory.
Link to the paper:
https://doi.org/10.1002/lpor.202200158
