摘要
为结合多入多出系统和超宽带的优点来实现高速高效的传输,将空时编码技术应用于超宽带系统中,讨论了基于脉冲位置调制(PPM:Pulse-Position Modulation)、脉冲幅度调制(PAM:Pulse-Amplitude Modulation)以及双正交调制3种不同方式的超宽带空时网格编码方案。考虑在发送和接收端已知信道状态信息,分别建立了3种方案的发射接收模型。仿真结果表明,在高斯信道和IEEE802.15.3a信道条件下,采用PPM的超宽带空时网格编码方案的性能都远优于其他两种方案,当信噪比为8dB时,误码率降低10~100倍。进一步考虑在存在多用户干扰条件下,该系统性能随用户数的增加而下降。
To exploit the advantages of both UWB (Ultra-WideBand) and MIMO ( Multiple-Input Multiple-Out- put), STrC (Space-Time Trellis Codes) is applied to UWB systems, and STrC-UWB systems with different modulations are discussed. Models of three schemes employing PPM ( Pulse-Position Modulation), PAM ( Pulse- Amplitude Modulation) and biorthogonal modulation are set up separately, and it is assumed that the channel state information can be obtained at both transmitter and receiver. Simulation results show STrC-UWB with PPM can achieve much better performance than the others under both Gaussian and IEEE802. 15.3a channel. The bit error rate of STIE-UWB with PPM is 10 - 100 times lower than the other two while the signal to noise ratio is 8 dB. So the scheme employing PPM is preferred and we further find when MUI ( Multi-User Interference) is considered the performance degrades when the number of users increases.
出处
《吉林大学学报(信息科学版)》
CAS
2007年第1期1-5,共5页
Journal of Jilin University(Information Science Edition)
基金
教育部科学技术研究重点基金资助项目(106059)
关键词
多入多出
超宽带
空时网格编码
multi-input multi-output (MIMO)
ultra-wide-band (UWB)
space-time trellis coding (STrC)