Based on the research on time domain and frequency domain transmitted reference Impulse Radio Ultra-WideBand (IR-UWB) system, this paper studies the optimization design for code domain transmitted reference IR-UWB sys...Based on the research on time domain and frequency domain transmitted reference Impulse Radio Ultra-WideBand (IR-UWB) system, this paper studies the optimization design for code domain transmitted reference IR-UWB system, and proposes a modified code domain transmitted reference IR-UWB system. The Bit Error Rate (BER) expressions for the modified system model in the condition of Additive White Gaussian Noise (AWGN) and multipath fading are deduced respectively. In addition, the performances of the modified system and the other three transmitted reference IR-UWB systems are simulated and compared. Theoretical analysis and simulation results show that the performance of the modified system is superior to the other three systems.展开更多
The detection performance is evaluated for our proposed analog multiuser receiver in Ultra-WideBand (UWB) transmitted-reference system. In the presence of dense multipath and multi-access signals,the performance analy...The detection performance is evaluated for our proposed analog multiuser receiver in Ultra-WideBand (UWB) transmitted-reference system. In the presence of dense multipath and multi-access signals,the performance analysis is difficult due to the complicated waveform of received impulse. We develop an approach to analyze the steady-state Signal-to-Interference-plus-Noise (SINR) of the detector output. The multipath-spread impulse is fitted to an exponentially decaying profile in the analysis. A closed-form expression of steady-state SINR is further deduced for the proposed Least Minimum Square (LMS) detector. The analysis is validated by simulations in Line-Of-Sight (LOS) and Non-Line-Of-Sight (NLOS) channel respectively. Based on the theoretical results,the multipath delay spread is employed to determine the optimal width of the integration window of the detector.展开更多
A cognitive radio transmitted reference ultra-wideband(CR-TR-UWB) system is proposed to improve the performance of TR-UWB systems with narrowband interference(NBI) from primary users(PU).The transmitter of the C...A cognitive radio transmitted reference ultra-wideband(CR-TR-UWB) system is proposed to improve the performance of TR-UWB systems with narrowband interference(NBI) from primary users(PU).The transmitter of the CR-TR-UWB system detects the band of PU,and then sends prolate spheroidal wave functions(PSWF) pulses with the same limited band as PU's to reduce interference with PU.The receiver uses a notch filter before autocorrelation to eliminate NBI from PU.The simulation results show that the bit error rate(BER) performance of the CR-TR-UWB system is close to that of TR-UWB systems without NBI when the system is interfered by single or double NBIs with a signal to interference ratio(SIR) of 0 dB,and if the signal to noise ratio(SNR) is 10 dB and the SIR varies from-20 to 10 dB,BER performance varies no more than an order of magnitude.The system has excellent resistance to NBI,strong robustness BER performance at different SNRs,and smaller interference with the same frequency band PU.展开更多
基金Supported by the National High Technology Research and Development Program of China(863 Program)(No.2009AA011205)the Important National Science and Technology Specific Projects(No.2009ZX03006-008)
文摘Based on the research on time domain and frequency domain transmitted reference Impulse Radio Ultra-WideBand (IR-UWB) system, this paper studies the optimization design for code domain transmitted reference IR-UWB system, and proposes a modified code domain transmitted reference IR-UWB system. The Bit Error Rate (BER) expressions for the modified system model in the condition of Additive White Gaussian Noise (AWGN) and multipath fading are deduced respectively. In addition, the performances of the modified system and the other three transmitted reference IR-UWB systems are simulated and compared. Theoretical analysis and simulation results show that the performance of the modified system is superior to the other three systems.
基金Supported by the Guangxi Natural Science Foundation (No.0731025, No.0731026)the Established Project by Guangxi Education Department (No.200808LX117)
文摘The detection performance is evaluated for our proposed analog multiuser receiver in Ultra-WideBand (UWB) transmitted-reference system. In the presence of dense multipath and multi-access signals,the performance analysis is difficult due to the complicated waveform of received impulse. We develop an approach to analyze the steady-state Signal-to-Interference-plus-Noise (SINR) of the detector output. The multipath-spread impulse is fitted to an exponentially decaying profile in the analysis. A closed-form expression of steady-state SINR is further deduced for the proposed Least Minimum Square (LMS) detector. The analysis is validated by simulations in Line-Of-Sight (LOS) and Non-Line-Of-Sight (NLOS) channel respectively. Based on the theoretical results,the multipath delay spread is employed to determine the optimal width of the integration window of the detector.
基金The National Research and Development Program of China(863 Program)(No.2007AA12Z238)the Natural Science Foundation of Jiangsu Higher Education Institutions of China(No. 12KJD510008)
文摘A cognitive radio transmitted reference ultra-wideband(CR-TR-UWB) system is proposed to improve the performance of TR-UWB systems with narrowband interference(NBI) from primary users(PU).The transmitter of the CR-TR-UWB system detects the band of PU,and then sends prolate spheroidal wave functions(PSWF) pulses with the same limited band as PU's to reduce interference with PU.The receiver uses a notch filter before autocorrelation to eliminate NBI from PU.The simulation results show that the bit error rate(BER) performance of the CR-TR-UWB system is close to that of TR-UWB systems without NBI when the system is interfered by single or double NBIs with a signal to interference ratio(SIR) of 0 dB,and if the signal to noise ratio(SNR) is 10 dB and the SIR varies from-20 to 10 dB,BER performance varies no more than an order of magnitude.The system has excellent resistance to NBI,strong robustness BER performance at different SNRs,and smaller interference with the same frequency band PU.