The photonic frequency-interleaving(PFI)technique has shown great potential for broadband signal acquisition,effectively overcoming the challenges of clock jitter and channel mismatch in the conventional time-interlea...The photonic frequency-interleaving(PFI)technique has shown great potential for broadband signal acquisition,effectively overcoming the challenges of clock jitter and channel mismatch in the conventional time-interleaving paradigm.However,current comb-based PFI schemes have complex system architectures and face challenges in achieving large bandwidth,dense channelization,and flexible reconfigurability simultaneously,which impedes practical applications.In this work,we propose and demonstrate a broadband PFI scheme with high reconfigurability and scalability by exploiting multiple free-running lasers for dense spectral slicing with high crosstalk suppression.A dedicated system model is developed through a comprehensive analysis of the system non-idealities,and a cross-channel signal reconstruction algorithm is developed for distortion-free signal reconstruction,based on precise calibrations of intra-and inter-channel impairments.The system performance is validated through the reception of multi-format broadband signals,both digital and analog,with a detailed evaluation of signal reconstruction quality,achieving inter-channel phase differences of less than 2°.The reconfigurability and scalability of the scheme are demonstrated through a dual-band radar imaging experiment and a three-channel interleaving implementation with a maximum acquisition bandwidth of 4 GHz.To the best of our knowledge,this is the first demonstration of a practical radio-frequency(RF)application enabled by PFI.Our work provides an innovative solution for next-generation software-defined broadband RF receivers.展开更多
The negative impact on communication performance in wireless multi-hop communication net-work caused by limited bandwidth,high bit eror rate (BER),fading,noise and interference is alleviated by an adaptive filtering...The negative impact on communication performance in wireless multi-hop communication net-work caused by limited bandwidth,high bit eror rate (BER),fading,noise and interference is alleviated by an adaptive filtering game based on frequency subbands selection and predetemined threshold.Such threshold is being obtained in Gaussian and multipath fading channel according to the frequency-matching principle and BER performance.The dynamic selection of subbands will obtain high use efficiency without the help of frequency hopping,and propound a new thought to improve band limited communication for wireless multi-hop communication network.The effectiveness of the adaptive filtering method has been verified by interleaving spread spectrum orthogonal frequency division multiplexing (ISS-OFDM) in different interference conditions,and the simulating results based on network simulator 2 (NS2) indicate that system BER can be improved greatly.展开更多
基金National Key Research and Development Program of China(2021YFB2800800)National Key Laboratory Program(E13D01012F)+4 种基金National Natural Science Foundation of China(62104232,62327806,61988102)Key Research Program of Frontier Sciences,CAS(ZDBS-LYJSC016)Guangdong Province Key Field RD Program Project(2020B0101110002)Science and Technology Planning Project of Guangdong Province(2019B090909011)Program of GBA Branch of AIRCAS(E0Z2D10600)。
文摘The photonic frequency-interleaving(PFI)technique has shown great potential for broadband signal acquisition,effectively overcoming the challenges of clock jitter and channel mismatch in the conventional time-interleaving paradigm.However,current comb-based PFI schemes have complex system architectures and face challenges in achieving large bandwidth,dense channelization,and flexible reconfigurability simultaneously,which impedes practical applications.In this work,we propose and demonstrate a broadband PFI scheme with high reconfigurability and scalability by exploiting multiple free-running lasers for dense spectral slicing with high crosstalk suppression.A dedicated system model is developed through a comprehensive analysis of the system non-idealities,and a cross-channel signal reconstruction algorithm is developed for distortion-free signal reconstruction,based on precise calibrations of intra-and inter-channel impairments.The system performance is validated through the reception of multi-format broadband signals,both digital and analog,with a detailed evaluation of signal reconstruction quality,achieving inter-channel phase differences of less than 2°.The reconfigurability and scalability of the scheme are demonstrated through a dual-band radar imaging experiment and a three-channel interleaving implementation with a maximum acquisition bandwidth of 4 GHz.To the best of our knowledge,this is the first demonstration of a practical radio-frequency(RF)application enabled by PFI.Our work provides an innovative solution for next-generation software-defined broadband RF receivers.
基金Supported by the National Nature Science Foundation of China(No.61302074)the Specialized Research Fund for the Doctoral Program of Higher Education(No.20122301120004)+1 种基金the Natural Science Foundation of Heilongjiang Province(No.QC2013C061)Research Foundation of Education Bureau of Heilongjiang Province(No.12531480)
文摘The negative impact on communication performance in wireless multi-hop communication net-work caused by limited bandwidth,high bit eror rate (BER),fading,noise and interference is alleviated by an adaptive filtering game based on frequency subbands selection and predetemined threshold.Such threshold is being obtained in Gaussian and multipath fading channel according to the frequency-matching principle and BER performance.The dynamic selection of subbands will obtain high use efficiency without the help of frequency hopping,and propound a new thought to improve band limited communication for wireless multi-hop communication network.The effectiveness of the adaptive filtering method has been verified by interleaving spread spectrum orthogonal frequency division multiplexing (ISS-OFDM) in different interference conditions,and the simulating results based on network simulator 2 (NS2) indicate that system BER can be improved greatly.