Object detection in aerial images is widely applied in many applications. In recent years, faster region convolutional neural network shows a great improvement on object detecting in natural images. Considering the size and distribution characteristic of object in remote sensing images, the region proposal network (RPN) should be changed before being adopted. In this letter, a scale adaptive proposal network (SAPNet) is proposed to improve the accuracy of multiobject detection in remote sensing images. The SAPNet consists of multilayer RPNs which are designed to generate multiscale object proposals, and a final detection subnetwork in which fusion feature layer has been applied for better multiobject detection. Comparative experimental results show that the proposed SAPNet significantly improves the accuracy of multiobject detection.
1 June 2020 in IEEE Transactions on Computer-Aided Design of Integrated Circuits and Systems
Conventional mapping method between RRAM array and convolutional weights faces two key challenges: (1) non-optimal energy efficiency and (2) RRAM’s temporal variation. To address these challenges, we propose “shift and duplicate kernel” (SDK) convolutional weight mapping architecture. Each kernel is duplicated multiple times and rearranged on different bitlines in a shifted manner, enabling higher intra-layer computational parallelism, and reducing the number of input data loading. Hence, this architecture reduces the computational latency and energy consumption in both forward and backward propagation phases. Furthermore, we have introduced a parallel-window size allocation algorithm and a kernel synchronization method. Our proposed parallel-window size allocation algorithm aims to balance the inter-layer pipeline architecture, thus improving the overall energy efficiency and area efficiency. Our proposed kernel synchronization method uses an averaging method to suppress the effect of temporal variation during weight update, enhancing the system’s robustness for training. From our experiment results, our proposed architecture achieves 6.8× area efficiency and 2.1× energy efficiency over the conventional inter-layer pipeline architecture. Significant improvement in classification accuracy by 21.7% under a temporal variation of 1% 5% is achieved during on-chip training task on the Cifar-10 dataset.
30 July 2020 in IEEE Transactions on Circuits and Systems I: Regular Papers
Aiming at reducing the complexity of minimum mean square error (MMSE) detection in massive multiple-input multiple-output (MIMO) systems, this paper proposes a detection algorithm with high convergence rate and an efficient hardware architecture based on second-order Richardson iteration (SORI). In the proposed algorithm, a pre-iteration-based initialization method is presented to accelerate the convergence without extra complexity. In addition, the approximation of relaxation factor and the log-likelihood ratio (LLR) is introduced to further reduce computing load. Theoretical analysis demonstrates the advantages of the proposed algorithm in fast convergence and low complexity, and simulation results show that the proposed algorithm can efficiently approach MMSE performance. Based on this algorithm, a flexible hardware architecture is designed, which is deeply pipelined to support 128x U (8≤ U≤ 32) massive MIMO detection with the configurable number of iterations, and a folded dual-mode systolic array (DMSA) is fully utilized to achieve the flexibility with low hardware consumption. Implemented on Xilinx Virtex-7 FPGA and SMIC 40nm CMOS technology, the proposed detector is competitive in terms of energy and area efficiency compared to state-of-the-art iterative detectors, and it can adapt to the varied channel condition and the number of users in massive MIMO systems.
15 January 2024 in IEEE Transactions on Circuits and Systems I: Regular Papers
Large language models (LLMs) have sparked a new revolution in the field of natural language processing (NLP), and have garnered tremendous attention in both academic research and everyday life, thanks to their unprecedented performance in a wide range of applications. However, their deployment remains a significant challenge, primarily due to their intensive computational and memory requirements. Hardware acceleration and efficient quantization are promising solutions to address the two issues. In this paper, a quantization and hardware architecture co-design is presented for matrix-vector multiplications (MVMs) of LLMs. During quantization, we uniformly group weights and activations to ensure workload balance for hardware. To enhance the performance of quantization, we further propose two approaches called channel sorting and channel selection, which can be applied simultaneously. To support the proposed quantization scheme, we develop two precision-scalable MVM hardware architectures. They are specifically designed for high speed and high energy efficiency, respectively. Experimental results show that our proposed quantization scheme achieves state-of-the-art performance among all the reported post-training schemes that quantize both weights and activations into integers. Compared to MVM architecture of the state-of-the-art LLM accelerator OliVe, our design exhibits significant advantages in terms of area efficiency and energy efficiency.
Recently, the single image super-resolution (SISR) based on deep learning algorithm has taken more attention from the research community. There are many methods that are developed to solve this task using CNNs methods. However, most of these methods need large computational resources and consume more runtime. Due to the fact that the runtime is essential for some applications, we propose a mixer-based local residual network (MLRN) for lightweight image super-resolution (SR). The idea of the MLRN model is based on mixing channel and spatial features and mixing low and high-frequency information. This is done by designing a mixer local residual block (MLRB) to be the backbone of our model. Moreover, the bilinear up-sampling is utilized to transfer and mix low-frequency information with extracted high-frequency information. Finally, the GELU activation is used in the main model, proving its efficiency for the SR task. The experimental results show the effectiveness of the model against other state-of-the-art lightweight models. Finally, we took part in the Efficient Super-Resolution 2023 Challenge and achieved good results.