This paper examines the robustness of anti-interference Ultra-Wide-Band UWB-OFDM （AI-UWB） systems in presence of narrow-band interference. It analyzes the bit error rate performance of the systems in both the single...This paper examines the robustness of anti-interference Ultra-Wide-Band UWB-OFDM （AI-UWB） systems in presence of narrow-band interference. It analyzes the bit error rate performance of the systems in both the single-user and multi-user modes, and compares its robustness in different code matrixes. By encoding transmitted symbols and spreading their power over all sub-bands, AI-UWB systems can make full use of the frequency diversity across the sub-bands and have more robustness to the narrowband interference. Simulating results show that different codes have almost the same robustness to the narrowband interference. The encoding and spreading could suppress the narrowband interference effectively. Compared with the IS-UWB systems, our approach has more than 5 dB interference margin.展开更多
An anti-interference orthogonal coding is introduced based on Hadamard code and Orthogonal Frequency-Division Multiplexing （OFDM）, in which all sub-channels of Ultra-WideBand （UWB） system are divided into M sub-ba...An anti-interference orthogonal coding is introduced based on Hadamard code and Orthogonal Frequency-Division Multiplexing （OFDM）, in which all sub-channels of Ultra-WideBand （UWB） system are divided into M sub-bands and the power of the every transmitted symbol spreads over each of the sub-bands rather than one sub-band. The complete mathematical analytical relation between encoding and decoding is present and the robustness of the system to interference is examined. When some sub-channels are affected by interference or jamming, the system could regenerate the symbol from others. Simulation results show that the Anti-Interference UWB-OFDM （AI-OFDM） system has evident advantages over conventional UWB-OFDM systems as well as the Interference Suppressing UWB-OFDM （IS-OFDM） in Bit Error Rate （BER） thanks to its robustness to interference. In the case of bad interference, the AI-OFDM system could work up to snuff without any anti-interference step, but the conventional UWB-OFDM system couldn＇t. Compared with the ISOFDM system, the AI-OFDM system improves the performance about 5 dB in Signal-to-Interference Ratio （SIR） and the order of 1-2 in BER.展开更多
文摘This paper examines the robustness of anti-interference Ultra-Wide-Band UWB-OFDM （AI-UWB） systems in presence of narrow-band interference. It analyzes the bit error rate performance of the systems in both the single-user and multi-user modes, and compares its robustness in different code matrixes. By encoding transmitted symbols and spreading their power over all sub-bands, AI-UWB systems can make full use of the frequency diversity across the sub-bands and have more robustness to the narrowband interference. Simulating results show that different codes have almost the same robustness to the narrowband interference. The encoding and spreading could suppress the narrowband interference effectively. Compared with the IS-UWB systems, our approach has more than 5 dB interference margin.
基金This workissupported by National"863"High Technology Research Programof China (2005AA123320) Universities Natural Science Research Pro-ject of Jiangsu Province (05KJB510101) .
文摘An anti-interference orthogonal coding is introduced based on Hadamard code and Orthogonal Frequency-Division Multiplexing （OFDM）, in which all sub-channels of Ultra-WideBand （UWB） system are divided into M sub-bands and the power of the every transmitted symbol spreads over each of the sub-bands rather than one sub-band. The complete mathematical analytical relation between encoding and decoding is present and the robustness of the system to interference is examined. When some sub-channels are affected by interference or jamming, the system could regenerate the symbol from others. Simulation results show that the Anti-Interference UWB-OFDM （AI-OFDM） system has evident advantages over conventional UWB-OFDM systems as well as the Interference Suppressing UWB-OFDM （IS-OFDM） in Bit Error Rate （BER） thanks to its robustness to interference. In the case of bad interference, the AI-OFDM system could work up to snuff without any anti-interference step, but the conventional UWB-OFDM system couldn＇t. Compared with the ISOFDM system, the AI-OFDM system improves the performance about 5 dB in Signal-to-Interference Ratio （SIR） and the order of 1-2 in BER.
