Highly-Selective Diplexer and High Q-Factor Hybrid Resonator Bandpass Filters for Broadband RF Transceiver Front-end Applications
Expectations are high for fast data access in both fixed and mobile wireless applications. According to the International Telecommunications Union (ITU), fifith-generation (5G) wireless communications networks should support data rates to 2 Gb/s for low-mobility applications and 100 Mb/s for high-mobility applications. To meet these requirements, advanced technologies are needed, including high-level modulation schemes, orthogonal frequency division multiplexing (OFDM), and MIMO techniques, and the channel bandwidth should be at least 100 MHz. However, most existing communications standards employ no more than 20 MHz bandwidth. Compare to a TDD communication system, an FDD scheme helps to obtain higher bidirectional data throughputs, simpler network arrangement for the RF transceiver and larger cell coverage, which is an attractive choice to support the high data rate communications. In order to explore the possibilities for high-data-rate wireless communications, a RF transceiver front-end module was designed and implemented. The requirements of the microwave RF system requirements and the advantages as well as the disadvantages of different transceiver structures are comprehensive considered and analyzed along with the trade-off between the RF system performance and implementation complexity. The RF transceiver front-end was operating from 2.65 GHz to 2.75 GHz for the transmitting and from 2.36 GHz to 2.44 GHz for the receiving with essential active components such as RF diplexer, bandpass filters, low noise amplifier, mixer, and oscillator haven been successfully designed and implemented. After careful design and optimization, the low cost miniature transceiver front-end module is fabricated on a single PCB board. The design and measurement RF performance of the proposed transceiver is detailed described. All the measured results indicate the performance of the broadband RF transceiver front-end module is superior to the requirements as well as can support high spectrum efficiency and high data rate communications with low EVM.
Transceiver, diplexer, bandpass filter, low EVM, hybrid resonator.
Trong-Hieu Le was born in Hanoi, Vietnam in 1986. He received the B.S. degree from Le Quy Don Technical University, Hanoi, Vietnam, in Electronics and Telecommunications, in June 2009. Since 2008-2009, he has been with the Viettel Group, where he has also been serving as the Design and Optimization radio network engineer. Mr. Le was a recipient of the Scholarship from the China Scholarship Council. After work, he received the M.Sc. and Ph.D. degrees in Electromagnetic Field and Microwave Technology from the State Key Laboratory of Millimeter Waves, School of Information Science and Engineering, Southeast University, Nanjing, China, in 2013 and 2018, respectively. Dr. Le is currently a lecturer in the Faculty of Electronics and Telecommunications, Electric Power University, Hanoi, Vietnam. His fields of research are RF/Microwave and Millimeter-waves circuits such as filters, amplifiers, antennas for wireless communication applications.