Browsing by Author "Tsai, Pei-Yun"

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A 75-Gb/s/mm(2) and Energy-Efficient LDPC Decoder Based on a Reduced Complexity Second Minimum Approximation Min-Sum Algorithm
(2020-04-01)
Lopez, Henry
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Chan, Hsun-Wei
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Chiu, Kang-Lun
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Tsai, Pei-Yun
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Jou, Shyh-Jye Jerry
This article presents a high-throughput and low-routing complexity low-density parity check (LDPC) decoder design based on a novel second minimum approximation min-sum (SAMS) algorithm. The routing congestion is mitigated by reducing the required interconnections in the critical path of the routing network. The implementation and postlayout results with 28-nm 1P9M CMOS process show that the proposed design can achieve a throughput of 10.5 Gb/s for a millimeter-wave 60-GHz baseband system while satisfying the low bit error rate (BER) requirements (10(-7)). The proposed design reduces the wiring in the routing network by 21% and improves the area by 12% compared to the conventional min-sum (MS) and normalized MS (NMS) algorithm. Additional hardware optimizations are obtained by considering the internal message passing resolution based on the BER and signal-to-noise ratio (SNR) requirements for a practical baseband system. The power consumption is efficiently reduced by the employment of a shared address generator that exploits the degree of parallelism to reduce the switching activity on a group of memory elements. The LDPC decoder is implemented with a core area of 0.14 mm(2), power consumption of 81 mW at 312.5 MHz, and the area and power efficiency of 75 Gb/s/mm(2) and 10.2 pJ/bit, respectively.
A Millimeter Wave Digital CMOS Baseband Transceiver for Wireless LAN Applications
(2019-01-01)
Chiu, Kang-Lun
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Chan, Hsun-Wei
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Lee, Wei-Che
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Wu, Chang-Ting
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Lopez, Henry
In this paper, we introduce a 10 Gbps digital baseband transceiver with IV supply voltage, 16-QAM, 3/4 code rate single carrier mode using 28 nm CMOS process to do the implementation. In millimeter wave communications, well-defined standard, IEEE 802.11ad is referenced for our system design and simulation. We target at modified chip rate 2.5 GHz with 4 times parallelism hardware at clock rate 625 MHz. The overall transceiver architecture design with hardware implementation considerations will be proposed. With the smart shared memory allocation, we can reduce 31% of the total amount. According to the referenced specifications, we achieve the required bit error rate 3 x 10(-7) before SNR 18.5 dB. After the system algorithm design, we implement the hardware with the core area 2.92 mm(2) with measured power 1.8 Watt for baseband transceiver chip. The performance of energ,y per bit is 0.023 nJ and 0.211 nJ per hit 6w Tx and Rx, including ADC/DAC.
Personalized Popular Blog Recommender Service for Mobile Applications
(2009)
Tsai, Pei-Yun
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Liu, Duen-Ren
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資訊管理與財務金融系註：原資管所+財金所
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Department of Information Management and Finance
Weblogs have emerged as a new communication and publication medium on the Internet for diffusing the latest useful information. Providing value-added mobile services such as blog articles is increasingly important to attract mobile users to mobile commerce. There are, however, a tremendous number of blog articles, and mobile users generally have difficulty in browsing weblogs. Accordingly, providing mobile users with blog articles that suit their interests is an important issue. Very little research, however, focuses on this issue. In this work, we propose a Customized Content Service on a mobile device (m-CCS) to filter and push blog articles to mobile users. The m-CCS can predict the latest popular blog topics by forecasting the trend of time-sensitive popularity of weblogs. Furthermore, to meet the diversified interest of mobile users, m-CCS further analyzes users' browsing logs to derive their interests, which are then used to recommend their preferred popular blog topics and articles. The prototype system of m-CCS demonstrates that the system can effectively recommend mobile users desirable blog articles with respect to both Popularity and personal interests.
Personalized recommendation of popular blog articles for mobile applications
(2011-05-01)
Liu, Duen-Ren
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Tsai, Pei-Yun
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Chiu, Po-Huan
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資訊管理與財務金融系註：原資管所+財金所
;
Department of Information Management and Finance
Weblogs have emerged as a new communication and publication medium on the Internet for diffusing the latest useful information. Providing value-added mobile services, such as blog articles, is increasingly important to attract mobile users to mobile commerce, in order to benefit from the proliferation and convenience of using mobile devices to receive information any time and anywhere. However, there are a tremendous number of blog articles, and mobile users generally have difficulty in browsing weblogs owing to the limitations of mobile devices. Accordingly, providing mobile users with blog articles that suit their particular interests is an important issue. Very little research, however, has focused on this issue. In this work, we propose a novel Customized Content Service on a mobile device (m-CCS) to filter and push blog articles to mobile users. The m-CCS includes a novel forecasting approach to predict the latest popular blog topics based on the trend of time-sensitive popularity of weblogs. Mobile users may, however, have different interests regarding the latest popular blog topics. Thus, the m-CCS further analyzes the mobile users' browsing logs to determine their interests, which are then combined with the latest popular blog topics to derive their preferred blog topics and articles. A novel hybrid approach is proposed to recommend blog articles by integrating personalized popularity of topic clusters, item-based collaborative filtering (CF) and attention degree (click times) of blog articles. The experiment result demonstrates that the m-CCS system can effectively recommend mobile users' desired blog articles with respect to both popularity and personal interests. (C) 2011 Elsevier Inc. All rights reserved.