The major approaches to the Time-Domain Equalizer (TEQ) design in DMT systemsare summarized. After pointing out that the optimal design method of Maximum ShorteningSignal-to-Noise Ration (MSSNR) TEQ can't be real-...The major approaches to the Time-Domain Equalizer (TEQ) design in DMT systemsare summarized. After pointing out that the optimal design method of Maximum ShorteningSignal-to-Noise Ration (MSSNR) TEQ can't be real-time implemented by DSP, we present a suboptimalMSSNR TEQ design method, which reduces the computational complexity greatly by using a new method toestimate the optimal delay Δ and a proposed step-by-step algorithm to compute the TEQ taps. Theresults of simulations show the validity of the suboptimal method.展开更多
The sine transform can be used as a tool to conquer the problems of discrete multi-tone (DMT) systems to increase the bit rate. In the proposed discrete sine transform based discrete multi-tone (DST-DMT) system, we ma...The sine transform can be used as a tool to conquer the problems of discrete multi-tone (DMT) systems to increase the bit rate. In the proposed discrete sine transform based discrete multi-tone (DST-DMT) system, we make use of the energy compaction property of the DST to reduce the channel effects on the transmitted signals. The mathematical model of the proposed DST system is presented in the paper. Simulation experiments have been carried out to test the effect of the proposed DST-DMT system. The results of these experiments show that the performance of the DST-DMT system is better than that of the traditional FFT-DMT system. The results also show that employing the proposed TEQ in the DST-DMT system can increase the bit rate by about 2.57 Mbps.展开更多
无线信道的凸峰型包络致使局部均衡效果下降,需要谨慎选择均衡器长度。首先,通过直接求逆和广义求逆两种方式实现均衡器的求解;然后,通过分析信道系数托普利兹矩阵的条件数和信号干扰噪声比(Signal to Interference plus Noise Ratio,SI...无线信道的凸峰型包络致使局部均衡效果下降,需要谨慎选择均衡器长度。首先,通过直接求逆和广义求逆两种方式实现均衡器的求解;然后,通过分析信道系数托普利兹矩阵的条件数和信号干扰噪声比(Signal to Interference plus Noise Ratio,SINR)来探究局部均衡失效与它们之间的关系,尽可能以低复杂度实现高可靠均衡,避免产生SINR局部凹点。仿真实验结果表明,直接求逆中,当有噪信道系数的托普利兹条件数持续增长到一定范围时,均衡器长度达到最低门限长度;当均衡器长度对应的信道托普利兹条件数大于或小于其临近两边均衡器长度对应的条件数,且差值大于3时,出现性能凹点的概率比较大。展开更多
Single-Carrier (SC) transmission with the same bandwidth as Multi-Carrier (MC) transmission (such as OFDM) may have far shorter symbol duration and is considered to be more robust against time selective fading. In thi...Single-Carrier (SC) transmission with the same bandwidth as Multi-Carrier (MC) transmission (such as OFDM) may have far shorter symbol duration and is considered to be more robust against time selective fading. In this paper, we proposed the novel equalization and signal separation schemes in time domain for short block length transmission, i.e., Block Linear Equalization (BLE) and Block Nonlinear Equalization (BNLE) on MIMO frequency selective fading channels. The proposed BLE uses the MMSE based inverse matrix in time domain and the BNLE utilizes the QRD-M (QR Decomposition with M algorithm) with appropriate receiver complexity. We compared the computational complexity among the conventional SC-FDE (Frequency Domain Equalization) scheme and the proposed equalizers. We also used the Low-Density Parity Check (LDPC) decoder concatenated to the proposed BLE and BNLE.展开更多
文摘The major approaches to the Time-Domain Equalizer (TEQ) design in DMT systemsare summarized. After pointing out that the optimal design method of Maximum ShorteningSignal-to-Noise Ration (MSSNR) TEQ can't be real-time implemented by DSP, we present a suboptimalMSSNR TEQ design method, which reduces the computational complexity greatly by using a new method toestimate the optimal delay Δ and a proposed step-by-step algorithm to compute the TEQ taps. Theresults of simulations show the validity of the suboptimal method.
文摘The sine transform can be used as a tool to conquer the problems of discrete multi-tone (DMT) systems to increase the bit rate. In the proposed discrete sine transform based discrete multi-tone (DST-DMT) system, we make use of the energy compaction property of the DST to reduce the channel effects on the transmitted signals. The mathematical model of the proposed DST system is presented in the paper. Simulation experiments have been carried out to test the effect of the proposed DST-DMT system. The results of these experiments show that the performance of the DST-DMT system is better than that of the traditional FFT-DMT system. The results also show that employing the proposed TEQ in the DST-DMT system can increase the bit rate by about 2.57 Mbps.
文摘无线信道的凸峰型包络致使局部均衡效果下降,需要谨慎选择均衡器长度。首先,通过直接求逆和广义求逆两种方式实现均衡器的求解;然后,通过分析信道系数托普利兹矩阵的条件数和信号干扰噪声比(Signal to Interference plus Noise Ratio,SINR)来探究局部均衡失效与它们之间的关系,尽可能以低复杂度实现高可靠均衡,避免产生SINR局部凹点。仿真实验结果表明,直接求逆中,当有噪信道系数的托普利兹条件数持续增长到一定范围时,均衡器长度达到最低门限长度;当均衡器长度对应的信道托普利兹条件数大于或小于其临近两边均衡器长度对应的条件数,且差值大于3时,出现性能凹点的概率比较大。
文摘Single-Carrier (SC) transmission with the same bandwidth as Multi-Carrier (MC) transmission (such as OFDM) may have far shorter symbol duration and is considered to be more robust against time selective fading. In this paper, we proposed the novel equalization and signal separation schemes in time domain for short block length transmission, i.e., Block Linear Equalization (BLE) and Block Nonlinear Equalization (BNLE) on MIMO frequency selective fading channels. The proposed BLE uses the MMSE based inverse matrix in time domain and the BNLE utilizes the QRD-M (QR Decomposition with M algorithm) with appropriate receiver complexity. We compared the computational complexity among the conventional SC-FDE (Frequency Domain Equalization) scheme and the proposed equalizers. We also used the Low-Density Parity Check (LDPC) decoder concatenated to the proposed BLE and BNLE.
