Multicore implementation of a multichannel parallel graphic equalizer

Numerous signal processing applications are emerging on mobile computing systems. These applications are subject to responsiveness constraints for user interactivity and, at the same time, must be optimized for energy efficiency. Many current embedded devices are composed of low-power multicore processors that offer a good trade-off between computational capacity and low power consumption. In this context, equalizers are widely used in multiple mobile-based applications such as “Music streaming” to adjust the levels of bass and treble in sound reproduction. In this study, we evaluate a graphic equalizer from audio, computational capacity, and energy efficiency perspectives, as well as the execution of multiple real-time equalizers running on an embedded quad-core processor of a mobile device. To this end, we experiment with the working frequencies as well as the parallelism that can be extracted from a quad-core ARM Cortex-A57. Results show that using high CPU frequencies and three or four cores, our parallel algorithm is able to equalize more than five channels per watt in real time with an audio buffer of 4096 samples, which implies a latency of 92.8 ms at the standard sample rate of 44.1 kHz.

     

Multicore implementation and performance analysis of a chaos based LSB steganography technique

Microsystem Technologies - Temporal complexity of data security algorithms for information exchange on internet is becoming a daunting challenge. Performance enhancement of these algorithms using...     

输油管道微小泄漏球形检测器的设计与实现

针对输油管道微小泄漏检测方法有限、检测成本高、阻塞管道风险大等问题,提出了新的解决方案:设计了一个基于ARM—Linux和MEMS传感器的球形管道内检测器,其直径小于待检测管道直径。详细论述了该检测方案的原理、球形检测器的硬件组成、软件设计等内容。通过在输水管道内的多次模拟泄漏实验,证明该球形检测器检测流程简单、运行安全,能有效地检测出泄漏并给出较精确的定位信息,为输油管线微小泄漏的高精度、低成本的实用检测提供了有力的技术支持。     

MIMO OFDM系统中一种V-BLAST检测算法的FPGA实现

给出了一种V-BLAST检测算法的FPGA实现方案,该算法基于Greville求伪逆的方法。设计主要考虑了流水线操作和并行度处理。算法在Xilinx公司的Vertex Ⅱ Pro系列FPGA中实现,在B3G TDD MIMO OFDM系统硬件平台上进行了验证,性能良好。     

Parallel SUMIS soft detector for large MIMO systems on multicore and GPU

The Journal of Supercomputing - The number of transmit and receiver antennas is an important factor that affects the performance and complexity of a MIMO system. A MIMO system with very large...     

便携式瓦斯检测仪管理系统的设计与实现

针对以人工登记为主的矿山便携式瓦斯检测仪发放和回收工作存在效率低下、工作流程繁琐及不利于管理和统计的问题,设计一种便携式瓦斯检测仪自动收发系统.该系统包括收发装置、服务器和Web客户端三部分,采用C-S和B-S共存的复合结构,以PHP作为开发语言,选用MySQL数据库.实际应用结果表明,该系统能够很好地完成仪表发放回收工作,便于科学的管理仪表,加快了矿山信息化和智能化的建设.     

mmWave communications for 5G: implementation challenges and advances

Science China Information Sciences - An equivalent system model (ESM) that can be used to calibrate a SAR system affected by both the effect of system errors and the Faraday rotation (FR) is...     

基于自适应脉冲压缩-Capon滤波器的MIMO阵列雷达CFAR检测器

针对强杂波背景和有限训练样本数量条件下采用脉内编码压缩波形的MIMO阵列雷达目标检测问题,借鉴自适应波束形成技术中Capon最小功率估计器的相干源信号对消思想,提出了自适应脉冲压缩—Capon滤波器(简记为APC-Capon滤波器),并基于此滤波器的输出设计了一种CFAR检测器.理论分析和数值仿真均表明,该滤波器能够在执行非迭代自适应脉冲压缩并抑制各发射波形自相关距离旁瓣和互相关干扰的同时,实现杂波信号对消,即杂波抑制功能.检测性能仿真表明,尽管相同尺寸参数(包括发射阵元数、接收阵元数、脉冲编码位数、相参脉冲个数)条件下,所设计的基于APC-Capon滤波技术的CFAR检测器的性能不如训练样本数量充足时基于匹配滤波+样本矩阵求逆(SMI)技术的AMF检测器,但是随着尺寸参数的适当增大,前者的检测性能将逐渐超过后者在较小尺寸参数时的检测性能,且不显著增加计算复杂度和训练样本数量,而后者则因大尺寸参数时对计算复杂度和训练样本数量的需求过高而在实际中难以实现.仿真还表明,APC-Capon滤波器及其相应的CFAR检测器对发射波形的相关性(包括自相关性能和互相关性能)有一定的依赖性,但随着发射波形数量的增加,这种依赖...     

A CFAR detector for MIMO array radar based on adaptive pulse compression-Capon filter

Under the condition of strong clutter and finite training samples,a novel CFAR detector based on the proposed adaptive pulse compression-Capon filter (APC-Capon filter) is presented for MIMO array radar which transmits intrapulse coded waveforms.Both theoretical analysis and numerical simulations show that the proposed APC-Capon filter can utilize the non-reiterative adaptive pulse compression technique to alleviate both range sidelobes and mutual interference;at the same time it also can borrows ideas from the coherent signals cancellation of adaptive beamforming to perform clutter suppression.The detection performance simulations show that,with the same size parameters (including code length and the numbers of transmitter elements,receiver elements as well as pulses),the proposed CFAR detector is inferior to the adaptive matched filter (AMF) detector.But as the size parameters increase,the proposed CFAR detector will gradually outperform the AMF detector with smaller size parameters,and more importantly,unlike the AMF detector which has a lot of difficulties in performing due to the inordinate demands for the computational complexity and training sample size,this demands of the proposed CFAR detector will not significantly increase.The simulations also show that,the correlation properties of these intrapulse coded waveforms have certain effect on the APC-Capon filter and its corresponding CFAR detector.But fortunately,the effect will decrease as the number of intrapulse coded waveforms increases.     

一种基于ATP微生物检测仪的设计与实现

介绍了一种基于三磷酸腺苷(ATP)生物发光原理的微生物含量检测方法,并利用这种方法设计了一种检测仪的软硬件系统.其中主要采用光电倍增管以及外部放大处理电路将ATP光信号转换为电脉冲信号,然后利用微控制器进行脉冲计数从而计算出待测物体中的ATP的浓度,通过μC/OS-Ⅱ实时操作系统以及μC/GUI图形库将结果实时地显示在触摸屏上,并同时保存在外部microSD卡中.最后对系统进行了详细测试并给出了相关数据.     

MIMO技术在无线通信领域的应用研究

在第4代移动通信技术（4G）飞速发展的今天,MIMO（MultipleInputMultipleOutput,多输入多输出）技术由于其在通信领域的先天技术优势,被广泛的应用于无线通信技术中。文章从MIMO从无线通信技术的发展引出MIMO的概念,详细介绍了MIMO的系统原理、关键技术应用研究、发展前景等。     

A GPU implementation of an iterative receiver for energy saving MIMO ID-BICM systems

Iterative detection and decoding in communication systems with multiple transmitter and receiver antennas suffer from a significant increase in the computational cost and energy consumption. Nowadays, application of specific high-performance computing techniques for signal processing in communication systems is receiving considerable attention. In this paper, we present an accelerated and efficient iterative receiver, which has been implemented following two strategies. First, we reduce the computational cost using parallelized algorithms executed on graphics processing unit. In addition, our receiver allows the selection between two types of detectors with different complexity and performance. The selection can be done to fulfill a given compromise between bit error rate and power consumption.     

Design and implementation of a new lightweight chaos-based cryptosystem to secure IoT communications

International Journal of Information Security - Internet of things (IoT) provides several applications such as intelligent urban transportation, smart factory, and smart health. In such systems,...     

Software Standards for the Multicore Era

Systems architects commonly use multiple cores to improve system performance. Unfortunately, multicore hardware is evolving faster than software technologies. New multicore software standards are necessary in light of the new challenges and capabilities that embedded multicore systems provide. The newly released Multicore Communications API standard targets small-footprint, highly efficient intercore and interchip communications.     

Hopfield neural network implementation of the optimal CDMAmultiuser detector

We investigate the application of Hopfield neural networks (HNN's) to the problem of multiuser detection in spread spectrum/CDMA (code division multiple access) communication systems. It is shown that the NP-complete problem of minimizing the objective function of the optimal multiuser detector (OMD) can be translated into minimizing an HNN “energy” function, thus allowing to take advantage of the ability of HNN's to perform very fast gradient descent algorithms in analog hardware and produce in real-time suboptimal solutions to hard combinatorial optimization problems. The performance of the proposed HNN receiver is evaluated via computer simulations and compared to that of other suboptimal schemes as well as to that of the OMD for both the synchronous and the asynchronous CDMA transmission cases. It is shown that the HNN detector exhibits a number of attractive properties and that it provides a powerful generalization of a well-known and extensively studied suboptimal scheme, namely the multistage detector     

木马网络通信特征提取模型的设计与实现

由于木马等窃密型恶意程序对网络安全的危害性日益增加,为了提高网络入侵检测系统对木马的检测效果,研究分析了木马的网络通信形式和特点,结合一种改进的序列联配算法,设计并实现了一个木马网络通信特征自动提取模型.该模型提高了对木马通信特征进行分析的自动化程度和准确性,实例测试表明了该模型的实用性和有效性.