GPU (Graphics Processing Unit) is used in various areas. Therefore, the demand for the verification of GPU programs is increasing. In this paper, we suggest the method to detect bank conflict by using symbolic executi...GPU (Graphics Processing Unit) is used in various areas. Therefore, the demand for the verification of GPU programs is increasing. In this paper, we suggest the method to detect bank conflict by using symbolic execution. Bank conflict is one of the bugs happening in GPU and it leads the performance of programs lower. Bank conflict happens when some processing units in GPU access the same shared memory. Symbolic execution is the method to analysis programs with symbolic values. By using it, we can detect bank conflict on GPU programs which use many threads. We implement a prototype of the detector for bank conflict and evaluate it with some GPU programs. The result states that we can detect bank conflict on the programs with no loop regardless of the number of threads.展开更多
采用余弦调制滤波器组代替传统的OFDM(Orthogonal Frequency Division Multiplexing,正交频分复用)系统中的IFFT/FFT(Inverse Fast Fourier Transform/Fast Fourier Transform,快速傅里叶变换)模块,从而实现基于余弦调制滤波器组的OFDM...采用余弦调制滤波器组代替传统的OFDM(Orthogonal Frequency Division Multiplexing,正交频分复用)系统中的IFFT/FFT(Inverse Fast Fourier Transform/Fast Fourier Transform,快速傅里叶变换)模块,从而实现基于余弦调制滤波器组的OFDM系统.在滤波器组的设计过程中,根据原型滤波器设计的一般要求及实际通信系统中实现的快速算法考虑,采用半正弦窗作为原型滤波器.在理想信道下,信号能够完全重建.实现过程中,余弦调制滤波器组采用IV型离散余弦变换的快速算法来实现.基于matlab软件的仿真平台下,结果表明基于余弦调制滤波器组的OFDM系统与传统OFDM系统相比,误码性能与PAPR(Peak to Average Power Ratio,峰值平均功率比)性能都有了较为明显的改善.展开更多
利用压缩感知和预留子载波技术,提出一种改进的余弦调制滤波器组多载波通信系统的时域脉冲干扰抑制方法。不同于传统采用滤波器组多载波(filter bank multi-carrier,FBMC)脉冲干扰抑制方法:该方案可以在已知时域脉冲干扰数目的情况下,...利用压缩感知和预留子载波技术,提出一种改进的余弦调制滤波器组多载波通信系统的时域脉冲干扰抑制方法。不同于传统采用滤波器组多载波(filter bank multi-carrier,FBMC)脉冲干扰抑制方法:该方案可以在已知时域脉冲干扰数目的情况下,对其位置与大小精确估计。接收端首先通过预留子载波上的信息进行脉冲干扰的预判,然后利用压缩感知贪婪基追踪算法估计出其他载波上的混合干扰,最后结合预判信息,在混合干扰中提取出纯净的脉冲干扰并予以消除。仿真实验对上述方法与传统干扰抑制方法进行了可靠性比较,在信噪比达到15 d B时,随着信噪比的提高,提出的干扰抑制方法能够更加有效地抑制时域脉冲干扰,极大地降低了系统的误符号率。展开更多
文摘GPU (Graphics Processing Unit) is used in various areas. Therefore, the demand for the verification of GPU programs is increasing. In this paper, we suggest the method to detect bank conflict by using symbolic execution. Bank conflict is one of the bugs happening in GPU and it leads the performance of programs lower. Bank conflict happens when some processing units in GPU access the same shared memory. Symbolic execution is the method to analysis programs with symbolic values. By using it, we can detect bank conflict on GPU programs which use many threads. We implement a prototype of the detector for bank conflict and evaluate it with some GPU programs. The result states that we can detect bank conflict on the programs with no loop regardless of the number of threads.
文摘采用余弦调制滤波器组代替传统的OFDM(Orthogonal Frequency Division Multiplexing,正交频分复用)系统中的IFFT/FFT(Inverse Fast Fourier Transform/Fast Fourier Transform,快速傅里叶变换)模块,从而实现基于余弦调制滤波器组的OFDM系统.在滤波器组的设计过程中,根据原型滤波器设计的一般要求及实际通信系统中实现的快速算法考虑,采用半正弦窗作为原型滤波器.在理想信道下,信号能够完全重建.实现过程中,余弦调制滤波器组采用IV型离散余弦变换的快速算法来实现.基于matlab软件的仿真平台下,结果表明基于余弦调制滤波器组的OFDM系统与传统OFDM系统相比,误码性能与PAPR(Peak to Average Power Ratio,峰值平均功率比)性能都有了较为明显的改善.
文摘利用压缩感知和预留子载波技术,提出一种改进的余弦调制滤波器组多载波通信系统的时域脉冲干扰抑制方法。不同于传统采用滤波器组多载波(filter bank multi-carrier,FBMC)脉冲干扰抑制方法:该方案可以在已知时域脉冲干扰数目的情况下,对其位置与大小精确估计。接收端首先通过预留子载波上的信息进行脉冲干扰的预判,然后利用压缩感知贪婪基追踪算法估计出其他载波上的混合干扰,最后结合预判信息,在混合干扰中提取出纯净的脉冲干扰并予以消除。仿真实验对上述方法与传统干扰抑制方法进行了可靠性比较,在信噪比达到15 d B时,随着信噪比的提高,提出的干扰抑制方法能够更加有效地抑制时域脉冲干扰,极大地降低了系统的误符号率。