Calibration Techniques For Concurrent Dual-band Multiport Receivers

Abstract

The development of 5G and 6G technologies has put forward new requirements for the communication front end. Concurrent dual-band transceivers based on multiport interferometers are drawing more and more attention. Its unique mechanism could result in full-duplex dual-band transmission/reception with a single core. Hence, the channel efficiency can be enhanced to maximize the data throughput. Unfortunately, the amplitude and phase imbalances encountered by traditional RF front ends still a↵ect the performance of such multiport front ends. Due to mutual interference, the situation could be worse for concurrent dual-band operations. To the best of our knowledge, calibration techniques for concurrent dual-band multiport front ends have yet to be studied. Therefore, a new calibration scheme directly for concurrent dual-band receivers is necessary and crucial for optimal performance. This work has proposed a novel data calibration scheme directly targeting a dualband six-port receiver. We’ve analyzed the sensitivity of the circuit from individual components. Furthermore, mathematical demonstrations of how di↵erent kinds of non-idealities impact the performance of the receiver are illustrated. Further, we have proved an affirmative e↵ect on mutual interference using this architecture compared to the typical method. Numerical investigations on its performance are also conducted. With the proposed scheme, a minimum of 36.2% improvement in EVM is reported, and the isolation between the dual-band signal under 256-QAM modulation is increased by 15.6 dB.