Experiment on 60-GHz MMW transmission performance in an optical fiber and wireless system

We experimentally investigate the transmission performance of 60-GHz signals over standard single-mode fiber (SSMF) and wireless links at different bit rates. Experimental results show that in a transmission of over 10-km SSMF and 1.3-m wireless link, bit rate reaches up to 5 Gb/s and bit error rate (BER) is less than 10 4 . The main limiting factor in such radio-over-fiber (ROF) systems is intersymbol interferences caused by the so-called walk-off effect when BER is below 10 8 . In addition, a transmission of over 20-km SSMF without chromatic dispersion compensation is briefly investigated. For a BER of 10 8 , the optical penalty is 2 dB.     

基于压扩变换的60GHz正交频分复用光载无线通信系统实验研究

提出并实验研究了在60GHz正交频分复用(OFDM)-光载无线通信(ROF)系统中采用压扩变换技术降低OFDM信号峰值平均功率比(PAPR),并提高系统的接收灵敏度。实验结果表明,携带基于压扩变换的2.5Gb/s60GHz的OFDM-ROF信号经标准单模光纤传输50km后,在无色散补偿和误码率为10-3的条件下,当入纤功率为12dBm时,系统接收灵敏度提高约2.3dB,并且当互补累积分布函数(CCDF)为10-4时,OFDM信号的PAPR下降约3dB。     

基于RS码及网格编码调制技术的60GHzOFDM-RoF系统

分析了60 GHz正交频分复用技术光纤无线通信系统中的子载波互拍及频率选择性衰落.提出利用里德-所罗门码级联网格编码调制技术结合符号交织来降低两者对系统性能的不良影响.采用符号交织来分散正交频分复用中子载波上的误码,然后通过高码率的里德-所罗门码级联实用的网格编码调制技术来纠正比特错误.仿真结果表明:经过符号交织后,误...     

Polarization multiplexing optical wireless-over fiber QPSK signal transmission in integration system at W-band

We propose and experimentally demonstrate a novel scheme to realize polarization-division-multiplexing quadrature-phase-shift-keying （PDM-QPSK） signal transmission over fiber, wireless and fiber at Wband （75-110 GHz）. The generation of polarization multiplexing millimeter-wave （mm-wave） wireless signal is based on the photonic technique. After 20-km fiber transmission, polarization diversity and heterodyne beating are implemented to convert the polarization components of the polarization-multiplexing signals from the optical baseband to W-band so that up to 16 Gb/s mm-wave signals can be delivered over 2-m 2~2 multiple-input multiple-output （MIMO） wireless link. At the receiver base station （BS）, polarization combination reconstructs the PDM-QPSK signal which is then launched into another 20-km fiber. In the experiment, coherent detection is introduced to improve receiver sensitivity and constant modulus algorithm （CMA） is applied for polarization de-multiplexing. The bit-error-ratio （BER） for 16-Gb/s PDM- QPSK signal delivery is below the forward-error-correction （FEC） threshold of 3.8× 10-3 with the optical signal-to-noise ratio （OSNR） above 11.8 dB.     

基于RS码及网格编码调制技术的60 GHz OFDM-RoF系统

分析了60 GHz正交频分复用技术光纤无线通信系统中的子载波互拍及频率选择性衰落.提出利用里德-所罗门码级联网格编码调制技术结合符号交织来降低两者对系统性能的不良影响.采用符号交织来分散正交频分复用中子载波上的误码,然后通过高码率的里德-所罗门码级联实用的网格编码调制技术来纠正比特错误.仿真结果表明:经过符号交织后,误码在子载波上的分布变得较均匀,有利于纠错|2.5 Gb/s正交频分复用信号采用RS-PTCM-64QAM方案比采用未编码的16QAM调制提高了5 dB左右的接收机灵敏度.     

Enhanced fourth-power algorithm for phase estimation with frequency separation in direct-detection optical OFDM systems

The optical orthogonal frequency division multiplexing(OFDM) signal is affected by impairments introduced by electrical filters and optical chromatic dispersion.An enhanced fourth-power algorithm for phase estimation with frequency separation is used to estimate and compensate the phase rotation of OFDM subcarriers.The performance of the proposed phase estimation algorithm is evaluated on a 4-Gb/s OFDM signal at different frequencies.Experimental results using the proposed algorithm show a 1.8-dB received power sensitivity improvement at a bit error rate of 1×10-4 after a 100-km standard single-mode fiber transmission,compared with the conventional technique.