An adaptive multi-user detector was developed for direct-sequence code division multiple access(DS-CDMA)systems corrupted by non-Gaussian channel noise,which can be quite detrimental to the performance of the multi-us...An adaptive multi-user detector was developed for direct-sequence code division multiple access(DS-CDMA)systems corrupted by non-Gaussian channel noise,which can be quite detrimental to the performance of the multi-user detectors based on classical white Gaussian assumption.This receiver simultaneously combats multiple-access interference(MAI)and non-Gaussian impulsive noise.The channel parameters are estimated and transmitted signals are jointly detected by a simple recursive algorithm derived from the EM/SAGE algorithm.Analytical and simulation results show that the proposed technique is robust with wider applicability than conventional multi-user detectors in terms of near-far resistance and bit-error ratio(BER)when either MAI or non-Gaussian impulsive noise is dominant.展开更多
The complexity and performance of staggered orthogonal frequency division multiplexed (OFDM)data transmission systems are discussed in this paper. As improved digital implemention with a computationalcomplexity reduct...The complexity and performance of staggered orthogonal frequency division multiplexed (OFDM)data transmission systems are discussed in this paper. As improved digital implemention with a computationalcomplexity reduction of 30% compared to previous systems￣[7] is Presented. Staggered OFDM data transmission canprovide high bandwidth efficiency vecy close to 2log_2M for M-ary signalling. For voiceband channels, improve-ment of 3dB and 12dB in Gaussian noise and impulse noise immunities respectively, are abtained over serial QAMtransmission. An analysis of the phase jitter immunsity for the staggered OFDM system with raised cosine shapingfilters is presented. The analysis and simulation results show that a staggered delay of half a baud period betweensubchannels with a 100% rolloff factor optimize the system performance phase jitter and provide an improve-ment of 2dB in phase jitter immunity over nonstaggered systems.展开更多
基金supported by the National Natural Science Foundation of China(No.60072001).
文摘An adaptive multi-user detector was developed for direct-sequence code division multiple access(DS-CDMA)systems corrupted by non-Gaussian channel noise,which can be quite detrimental to the performance of the multi-user detectors based on classical white Gaussian assumption.This receiver simultaneously combats multiple-access interference(MAI)and non-Gaussian impulsive noise.The channel parameters are estimated and transmitted signals are jointly detected by a simple recursive algorithm derived from the EM/SAGE algorithm.Analytical and simulation results show that the proposed technique is robust with wider applicability than conventional multi-user detectors in terms of near-far resistance and bit-error ratio(BER)when either MAI or non-Gaussian impulsive noise is dominant.
文摘The complexity and performance of staggered orthogonal frequency division multiplexed (OFDM)data transmission systems are discussed in this paper. As improved digital implemention with a computationalcomplexity reduction of 30% compared to previous systems￣[7] is Presented. Staggered OFDM data transmission canprovide high bandwidth efficiency vecy close to 2log_2M for M-ary signalling. For voiceband channels, improve-ment of 3dB and 12dB in Gaussian noise and impulse noise immunities respectively, are abtained over serial QAMtransmission. An analysis of the phase jitter immunsity for the staggered OFDM system with raised cosine shapingfilters is presented. The analysis and simulation results show that a staggered delay of half a baud period betweensubchannels with a 100% rolloff factor optimize the system performance phase jitter and provide an improve-ment of 2dB in phase jitter immunity over nonstaggered systems.
