滤波器组多载波(Filter Bank Multi-Carrier,FBMC)与偏移正交振幅调制(Offset Quadrature Amplitude Modulation,OQAM)相结合的FBMC-OQAM技术在无线通信系统中具有频谱效率高和无需同步等特点。然而,FBMC-OQAM系统较高的峰均功率比(Peak...滤波器组多载波(Filter Bank Multi-Carrier,FBMC)与偏移正交振幅调制(Offset Quadrature Amplitude Modulation,OQAM)相结合的FBMC-OQAM技术在无线通信系统中具有频谱效率高和无需同步等特点。然而,FBMC-OQAM系统较高的峰均功率比(Peak-to-Average Power Ratio,PAPR)容易导致信号失真、频谱扩展、系统性能下降。鉴于此,文中提出一种载波预留(Tone Reservation,TR)和μ-律压扩联合的新方法(TR-μLaw)来降低FBMCOQAM系统的PAPR。TR方法具有无失真特性,而μ-律压扩法虽然给FBMC-OQAM系统带来了一定失真,但是能显著降低PAPR。TR-μLaw方法将二者结合,实现了两种方法的利弊互补。仿真结果表明,TR-μLaw方法在降低PAPR方面的性能优于μ-律压扩法和TR方法,在μ=3和Iterations=8时TR-μLaw方法的PAPR较后两者分别降低约1.0dB和3.4dB,且BER性能优于μ-律压扩法。展开更多
As the important complementary to terrestrial mobile communications, Internet via satellite can extend the coverage of communication and improve the continuity of data services. To build a space-terrestrial integrated...As the important complementary to terrestrial mobile communications, Internet via satellite can extend the coverage of communication and improve the continuity of data services. To build a space-terrestrial integrated communication system is the inevitable trend in the future. Taking into account combination of 5th generation(5G) terrestrial mobile communication system and satellite communication system, it is necessary to evaluate the promising 5G air interface waveform which can be adopted by satellite. In this paper, several non-orthogonal multi-carrier transmission schemes are evaluated and generalized frequency division multiplexing(GFDM) is advised as potential scheme of space-terrestrial integrated communication system. After the overview of GFDM, the implementation of GFDM transceiver is discussed respectively in time-domain and in frequency-domain. By deriving and comparing implementation complexity, GFDM modulation in time-domain is more suitable for satellite communication system. Then the properties of demodulation algorithms are specified. Based on designed pilot subcarriers, a new improved receiving algorithm is proposed in the end of the paper. The improved algorithm solves the problem of inter subcarriers interference(ICI) in matched filtering(MF) receiver and improves the re-ceiving symbol error rate(SER) obviously. The simulation and analysis prove that the proposed algorithm is effective.展开更多
The parallel interference c an cellation for multi-carrier DS-CDMA (which is termed FDC-PIC) is proposed by integrating frequency diversity combination. The simulations are made over FDC- PIC with respect to different...The parallel interference c an cellation for multi-carrier DS-CDMA (which is termed FDC-PIC) is proposed by integrating frequency diversity combination. The simulations are made over FDC- PIC with respect to different decision ways——hard, soft and linear decisions, respectively, and we conclude that FDC-PIC acquires superior performance improv ement over correlation reception of multi-carrier DS CDMA. With an increase in interference cancellation stages, the system performance is improved further. Th e initial 2 stages bring about the most dominant performance improvement, but up to the 3rd stage the system performance is improved little. It is also shown by the simulation results that FDC-PIC with soft decision would exhibit the best performance with a high implementation complexity, while FDC-PIC with linear de cision acquires performance comparable to that of FDC-PIC with soft decision wi th a reduced-complexity if the number of the interference cancellation stages i s the same, which indicates that FDC-PIC with linear decision has optimal perfo rmance/complexity tradeoff and therefore will be suitable for practical applica tion in future.展开更多
文摘滤波器组多载波(Filter Bank Multi-Carrier,FBMC)与偏移正交振幅调制(Offset Quadrature Amplitude Modulation,OQAM)相结合的FBMC-OQAM技术在无线通信系统中具有频谱效率高和无需同步等特点。然而,FBMC-OQAM系统较高的峰均功率比(Peak-to-Average Power Ratio,PAPR)容易导致信号失真、频谱扩展、系统性能下降。鉴于此,文中提出一种载波预留(Tone Reservation,TR)和μ-律压扩联合的新方法(TR-μLaw)来降低FBMCOQAM系统的PAPR。TR方法具有无失真特性,而μ-律压扩法虽然给FBMC-OQAM系统带来了一定失真,但是能显著降低PAPR。TR-μLaw方法将二者结合,实现了两种方法的利弊互补。仿真结果表明,TR-μLaw方法在降低PAPR方面的性能优于μ-律压扩法和TR方法,在μ=3和Iterations=8时TR-μLaw方法的PAPR较后两者分别降低约1.0dB和3.4dB,且BER性能优于μ-律压扩法。
文摘As the important complementary to terrestrial mobile communications, Internet via satellite can extend the coverage of communication and improve the continuity of data services. To build a space-terrestrial integrated communication system is the inevitable trend in the future. Taking into account combination of 5th generation(5G) terrestrial mobile communication system and satellite communication system, it is necessary to evaluate the promising 5G air interface waveform which can be adopted by satellite. In this paper, several non-orthogonal multi-carrier transmission schemes are evaluated and generalized frequency division multiplexing(GFDM) is advised as potential scheme of space-terrestrial integrated communication system. After the overview of GFDM, the implementation of GFDM transceiver is discussed respectively in time-domain and in frequency-domain. By deriving and comparing implementation complexity, GFDM modulation in time-domain is more suitable for satellite communication system. Then the properties of demodulation algorithms are specified. Based on designed pilot subcarriers, a new improved receiving algorithm is proposed in the end of the paper. The improved algorithm solves the problem of inter subcarriers interference(ICI) in matched filtering(MF) receiver and improves the re-ceiving symbol error rate(SER) obviously. The simulation and analysis prove that the proposed algorithm is effective.
基金National Natural Science Foundation of China (60372056)
文摘The parallel interference c an cellation for multi-carrier DS-CDMA (which is termed FDC-PIC) is proposed by integrating frequency diversity combination. The simulations are made over FDC- PIC with respect to different decision ways——hard, soft and linear decisions, respectively, and we conclude that FDC-PIC acquires superior performance improv ement over correlation reception of multi-carrier DS CDMA. With an increase in interference cancellation stages, the system performance is improved further. Th e initial 2 stages bring about the most dominant performance improvement, but up to the 3rd stage the system performance is improved little. It is also shown by the simulation results that FDC-PIC with soft decision would exhibit the best performance with a high implementation complexity, while FDC-PIC with linear de cision acquires performance comparable to that of FDC-PIC with soft decision wi th a reduced-complexity if the number of the interference cancellation stages i s the same, which indicates that FDC-PIC with linear decision has optimal perfo rmance/complexity tradeoff and therefore will be suitable for practical applica tion in future.
