为进一步提高煤矿井下通信系统传输信息的效率,介绍OFDM和自适应OFDM技术,讨论OFDM的系统结构和性能。在此基础上提出了一种自适应OFDM(Orthogonal Frequency Division Multiplexing)系统。在信道状况完全已知的假设下,设计了能根据信...为进一步提高煤矿井下通信系统传输信息的效率,介绍OFDM和自适应OFDM技术,讨论OFDM的系统结构和性能。在此基础上提出了一种自适应OFDM(Orthogonal Frequency Division Multiplexing)系统。在信道状况完全已知的假设下,设计了能根据信道特征动态改变其比特和功率分配的自适应OFDM算法。通过对煤矿井下无线信道特征的分析,建立了信道模型,并通过仿真检验了将自适应OFDM技术应用到煤矿井下进行无线数据传输的可行性。展开更多
For the high peak-to-average power ratio(PAPR) of coherent optical orthogonal frequency division multiplexing(CO-OFDM) system, a novel joint technique which is the combination of iterative partial transmit sequence(IP...For the high peak-to-average power ratio(PAPR) of coherent optical orthogonal frequency division multiplexing(CO-OFDM) system, a novel joint technique which is the combination of iterative partial transmit sequence(IPTS) and clipping technique is proposed. Simulation results demonstrate that the PAPR and bit error rate(BER) performance of the proposed technique both outperform those of the single techniques. Under the same conditions, the threshold value and peak power of IPTS clipping joint technique are optimized by 3.44 dB and 0.86 dBm compared with those of IPTS techinque, respectively. At the BER of 10-3, the optical signal to noise ratios(OSNRs) of the novel joint technique after 320 km and 400 km single-mode fiber(SMF) transmission are 0.68 dB and 1.18 dB smaller than those of clipping technique, respectively.展开更多
文摘为进一步提高煤矿井下通信系统传输信息的效率,介绍OFDM和自适应OFDM技术,讨论OFDM的系统结构和性能。在此基础上提出了一种自适应OFDM(Orthogonal Frequency Division Multiplexing)系统。在信道状况完全已知的假设下,设计了能根据信道特征动态改变其比特和功率分配的自适应OFDM算法。通过对煤矿井下无线信道特征的分析,建立了信道模型,并通过仿真检验了将自适应OFDM技术应用到煤矿井下进行无线数据传输的可行性。
基金supported by the National High Technology Research and Development Program of China(No.2013AA014201)the Natural Science Foundation of Tianjin(No.13QNJC01800)
文摘For the high peak-to-average power ratio(PAPR) of coherent optical orthogonal frequency division multiplexing(CO-OFDM) system, a novel joint technique which is the combination of iterative partial transmit sequence(IPTS) and clipping technique is proposed. Simulation results demonstrate that the PAPR and bit error rate(BER) performance of the proposed technique both outperform those of the single techniques. Under the same conditions, the threshold value and peak power of IPTS clipping joint technique are optimized by 3.44 dB and 0.86 dBm compared with those of IPTS techinque, respectively. At the BER of 10-3, the optical signal to noise ratios(OSNRs) of the novel joint technique after 320 km and 400 km single-mode fiber(SMF) transmission are 0.68 dB and 1.18 dB smaller than those of clipping technique, respectively.
