{"title":"XOR-Free Approach for Implementation of Polar Encoder","authors":"Navin Kumar;Deepak Kedia;Gaurav Purohit","doi":"10.1109/LES.2024.3495657","DOIUrl":"https://doi.org/10.1109/LES.2024.3495657","url":null,"abstract":"This letter presents a new algorithmic approach to construct an XOR-Free architecture for a nonsystematic polar encoder (NSPE). Optimization of XOR units is the main concern while implementing NSPE, which consumes a significant amount of dynamic power. To generate polar sequences of code length N, the approach uses <inline-formula> <tex-math>$(N/2)-1$ </tex-math></inline-formula> binary patterns extracted from the <inline-formula> <tex-math>$(N/2)^{mathrm { th}}$ </tex-math></inline-formula> order generator matrix <inline-formula> <tex-math>$G_{N/2}$ </tex-math></inline-formula> instead of <inline-formula> <tex-math>$G_{N}$ </tex-math></inline-formula>. The algorithm reduces the logical operations by virtue of the recursive patterns, thereby improving hardware (HW) cost. The pattern logics are inferred with 2:1 multiplexers and inverters, making the implementation XOR-Free. An auto HDL code generation script is written targeting variable code lengths (<inline-formula> <tex-math>$2{^{{3}}} leq {N} leq 2{^{{10}}}$ </tex-math></inline-formula>) for direct comparison with similar approaches, viz. stage folded and punctured NSPE design. The results show that the proposed architecture improves area by 31%–83% and power consumption by 15%–57% for various N and code rates (<inline-formula> <tex-math>$R{=}1$ </tex-math></inline-formula>, 1/2) on Virtex-6 FPGA devices.","PeriodicalId":56143,"journal":{"name":"IEEE Embedded Systems Letters","volume":"17 3","pages":"184-187"},"PeriodicalIF":1.7,"publicationDate":"2024-11-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144272954","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Wanju Doh;Seoyoung Ko;Michael Jaemin Kim;Jung Ho Ahn
{"title":"Hechi: A Hybrid Approach for Efficient Memory Reclamation Techniques in Mobile Systems","authors":"Wanju Doh;Seoyoung Ko;Michael Jaemin Kim;Jung Ho Ahn","doi":"10.1109/LES.2024.3494854","DOIUrl":"https://doi.org/10.1109/LES.2024.3494854","url":null,"abstract":"Application startup time, the time it takes for an application to become visible to the user from startup, is a crucial factor affecting user experience in mobile systems. The startup time of applications switching from the background (switching time) depends largely on the number of pages read from storage. When an application starts for the first time or reloads after being killed, it suffers from longer startup time (cold-launch time) as it begins from scratch. To mitigate this, minimizing application kills while retaining essential data in main memory can help, but it involves a tradeoff: reclaiming more file-backed pages (<monospace>file</monospace> pages) slows down switching due to the overhead of fetching them from storage, while reclaiming more anonymous pages (<monospace>anon</monospace> pages) that not associated with any file risks app termination due to limited swap space. Hechi addresses this tradeoff using a hybrid memory reclamation approach. By deprioritizing the reclamation of essential file pages and dynamically adjusting the reclamation ratio of the two types of pages based on the system states, Hechi improves startup time by up to 17%.","PeriodicalId":56143,"journal":{"name":"IEEE Embedded Systems Letters","volume":"17 3","pages":"192-195"},"PeriodicalIF":1.7,"publicationDate":"2024-11-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144272851","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Development of a Miniaturized Testing System for Resonant Frequency Difference Detection for Delay Line Surface Acoustic Wave Devices","authors":"Tao Li;Rui Sun;Rong Zhang;Cuiping Li;Huimin Liu","doi":"10.1109/LES.2024.3486992","DOIUrl":"https://doi.org/10.1109/LES.2024.3486992","url":null,"abstract":"This letter presents a resonant frequency difference (RFD) readout system for a surface acoustic wave (SAW) device using the feedback/loop method. The proposed miniaturized testing system with a nice interactive interface which offers a reliable and accurate solution for real-time monitoring of RFD signals. The design details of the system, including the selection of components, circuitry, and signal processing techniques, are discussed. Compare with the theoretical analysis results of commercial vector network analyzer, the test results error of this system do not exceed 0.2%.","PeriodicalId":56143,"journal":{"name":"IEEE Embedded Systems Letters","volume":"17 3","pages":"200-203"},"PeriodicalIF":1.7,"publicationDate":"2024-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144272963","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Configurable Multiport Memory Architecture for High-Speed Data Communication","authors":"Narendra Singh Dhakad;Santosh Kumar Vishvakarma","doi":"10.1109/LES.2024.3485509","DOIUrl":"https://doi.org/10.1109/LES.2024.3485509","url":null,"abstract":"Memory management is necessary with the increasing number of multiconnected AI devices and data bandwidth issues. For this purpose, high-speed multiport memory is used. The traditional multiport memory solutions are hard-bounded to a fixed number of ports for read or write operations. In this letter, we proposed a pseudo-quad-port memory architecture. Here, ports can be configured (1-port, 2-port, 3-port, and 4-port) for all possible combinations of read/write operations for the 6T static random access memory (SRAM) memory array, which improves the speed and reduces the bandwidth for data transfer. The proposed architecture improves the bandwidth of data transfer by <inline-formula> <tex-math>$4times $ </tex-math></inline-formula>. The architecture provides <inline-formula> <tex-math>$1.3times $ </tex-math></inline-formula> and <inline-formula> <tex-math>$2times $ </tex-math></inline-formula> area efficiency compared to dual-port 8T and quad-port 12T SRAM.","PeriodicalId":56143,"journal":{"name":"IEEE Embedded Systems Letters","volume":"17 3","pages":"139-142"},"PeriodicalIF":1.7,"publicationDate":"2024-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144272964","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Adaptive Extended Kalman Filtering for Battery State of Charge Estimation on STM32","authors":"António Barros;Edoardo Peretti;Davide Fabroni;Diego Carrera;Pasqualina Fragneto;Giacomo Boracchi","doi":"10.1109/LES.2024.3489352","DOIUrl":"https://doi.org/10.1109/LES.2024.3489352","url":null,"abstract":"Accurate and computationally light algorithms for estimating the state of charge (SoC) of a battery’s cells are crucial for effective battery management on embedded systems. In this letter, we propose an adaptive extended Kalman filter (AEKF) for SoC estimation using a covariance adaptation technique based on maximum likelihood estimation—a novelty in this domain. Furthermore, we tune a key design parameter—the estimation window size—to obtain an optimal memory-performance tradeoff, and experimentally demonstrate our solution achieves superior estimation accuracy with respect to existing alternative methods. Finally, we present a fully custom implementation of the AEKF for a general-purpose low-cost STM32 microcontroller, showing it can be deployed with minimal computational requirements adequate for real-world usage.","PeriodicalId":56143,"journal":{"name":"IEEE Embedded Systems Letters","volume":"17 3","pages":"160-163"},"PeriodicalIF":1.7,"publicationDate":"2024-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144272955","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Aditya Anirudh Jonnalagadda;Rishi Thotli;Sreehari Veeramachaneni;Uppugunduru Anil Kumar;Syed Ershad Ahmed
{"title":"Energy-Efficient Decoding and Encoding Hardware for Optimized Posit Arithmetic","authors":"Aditya Anirudh Jonnalagadda;Rishi Thotli;Sreehari Veeramachaneni;Uppugunduru Anil Kumar;Syed Ershad Ahmed","doi":"10.1109/LES.2024.3485002","DOIUrl":"https://doi.org/10.1109/LES.2024.3485002","url":null,"abstract":"The posit number system represents a binary numerical format devised primarily to mitigate the shortcomings of the IEEE 754 floating-point standard commonly used in modern computer arithmetic. Unlike IEEE 754, which utilizes a fixed-width representation, posits offer a variable-size encoding, dynamically adjusting the number of bits allocated based on the magnitude of the represented number. This adaptability enables posits to provide enhanced precision across a broader range of values, addressing issues like gradual underflow and the multiple representations of zero and NaN values inherent in IEEE 754. However, the dynamic bit allocation also poses significant challenges in decoding the posit number into its constituent fields and packing back the fields of the resultant posit once the arithmetic operations have been performed. For posits to become a viable alternative to floating-points in practical computing systems, the decoding and encoding overheads of posits need to be minimized. Hence, the aim of this letter is to develop energy-efficient hardware for posit decoding and encoding. The proposed <inline-formula> <tex-math>$langle 16,2rangle $ </tex-math></inline-formula> posit decoders, Decoders A and B show an improvement of over 65% and 33% compared to literature in terms of energy requirements. Similarly, the proposed <inline-formula> <tex-math>$langle 16,2rangle $ </tex-math></inline-formula> encoder circuit is over 52% more energy-efficient than existing encoder circuits.","PeriodicalId":56143,"journal":{"name":"IEEE Embedded Systems Letters","volume":"17 3","pages":"131-134"},"PeriodicalIF":1.7,"publicationDate":"2024-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144272852","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Developing Compact Models Using Regression Confidence Forge Knowledge Distillation for IMU-Based Indoor Positioning System","authors":"Nur Achmad Sulistyo Putro;Jenq-Shiou Leu;Nias Ananto;Cries Avian;Muhammad Izzuddin Mahali;Setya Widyawan Prakosa","doi":"10.1109/LES.2024.3487236","DOIUrl":"https://doi.org/10.1109/LES.2024.3487236","url":null,"abstract":"This letter focuses on developing practical and resource-efficient solutions for indoor positioning systems using inertial measurement unit sensors (IMU) by introducing a compact and efficient model. The model, derived from the robust neural inertial navigation (RoNIN) architecture, features a lightweight model that is achieved by reducing the number of filters. A specific knowledge distillation (KD) method, regression confidence forge (ReCoF) KD, is proposed and employed to address potential performance implications, enhancing the efficacy of the streamlined model. The smallest proposed model exhibits an 86% size reduction from RoNIN Resnet, leading to an 18.8% acceleration in inference time and 56% more power efficiency on the edge. Notably, the proposed model maintains high performance, as evidenced by its absolute trajectory error (ATE) and relative trajectory error (RTE).","PeriodicalId":56143,"journal":{"name":"IEEE Embedded Systems Letters","volume":"17 2","pages":"99-102"},"PeriodicalIF":1.7,"publicationDate":"2024-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143845337","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"VANet: A Solution for Ventricular Arrhythmias Detection of IEGM on Embedded Devices","authors":"Chaoyao Shen;Cheng Chen;Meng Zhang","doi":"10.1109/LES.2024.3483895","DOIUrl":"https://doi.org/10.1109/LES.2024.3483895","url":null,"abstract":"Real time detection of ventricular arrhythmias (VAs) in patients and timely provision of defibrillation treatment are crucial in the recording of intracardiac electrograms (IEGMs). Recently, deep convolutional networks have been used to detect VAs in IEGM recordings. However, due to their complex computations and model structures make them difficult to deploy on resource-constrained, low-power embedded devices. This letter introduces VANet, a fully convolutional lightweight neural network architecture for detecting VAs in IEGM recordings. Our hardware INT8 quantization implementation method effectively enables its deployment on embedded devices. Results show that it achieves the best performance in terms of accuracy, storage, and latency compared to state-of-the-art network architectures, X-Cube-AI and Tensorflow Lite Micro libraries.","PeriodicalId":56143,"journal":{"name":"IEEE Embedded Systems Letters","volume":"17 3","pages":"176-179"},"PeriodicalIF":1.7,"publicationDate":"2024-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144272957","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Design of an Embedded System for Integrated Underwater Communication and Detection","authors":"Jing Yan;Lifang Cui;Xian Yang;Cailian Chen;Xinping Guan","doi":"10.1109/LES.2024.3485608","DOIUrl":"https://doi.org/10.1109/LES.2024.3485608","url":null,"abstract":"This letter develops an embedded system for integrated underwater communication and detection. Specifically, it consists of an integrated waveform modulator, an echo signal detector and a communication waveform demodulator. For the waveform modulator, the time division modulation technology is adopted to design hybrid frequency multicarrier (MC) waveforms, such that the communication and detection signals can be integrated on the same channel. Based on this, the echo signal detector is designed to estimate the target parameters by extracting the delay and doppler frequency shift with a frequency domain matching filter. Meanwhile, the communication waveform demodulator is developed to receive data by demodulating frequency domain MC mapping. Finally, experimental results are given to verify the effectiveness of our embedded system.","PeriodicalId":56143,"journal":{"name":"IEEE Embedded Systems Letters","volume":"17 2","pages":"83-86"},"PeriodicalIF":1.7,"publicationDate":"2024-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143845507","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Zhuowen Zou;Yang Ni;SungHeon Jeong;Satish Ravindran;Binbin Shi;Phil Chen;Mohsen Imani
{"title":"DynHD: Hyperdimensional Computing Approach for Efficient Radar Spectrum Classification","authors":"Zhuowen Zou;Yang Ni;SungHeon Jeong;Satish Ravindran;Binbin Shi;Phil Chen;Mohsen Imani","doi":"10.1109/LES.2024.3485638","DOIUrl":"https://doi.org/10.1109/LES.2024.3485638","url":null,"abstract":"Radar technology plays a critical role in target detection, classification, and tracking. However, the computational demands of training deep neural networks (DNNs) on radar signals can be overwhelming, posing challenges for edge devices with limited energy and computing resources. In this article, we propose leveraging hyperdimensional computing (HDC), a brain-inspired computing paradigm, as an efficient alternative. HDC utilizes high-dimensional vectors for information representation and processing, offering robustness and energy efficiency. We propose a novel HDC classification algorithm named DynHD, with a dynamic HDC encoder that adapts to more challenging radar spectrum recognition tasks. We designed this mechanism to provide great flexibility to the HDC encoder that is otherwise fixed. Our evaluations demonstrate that HDC-based approaches achieve comparable accuracy to DNN-based methods with lower-computational complexity, making them suitable for resource-constrained devices. We achieve significant improvements in latency during training and inference phases, enabling efficient processing of radar signals on edge devices.","PeriodicalId":56143,"journal":{"name":"IEEE Embedded Systems Letters","volume":"17 2","pages":"95-98"},"PeriodicalIF":1.7,"publicationDate":"2024-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10734137","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143845510","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}