• Title/Summary/Keyword: logic gates

Search Result 256, Processing Time 0.033 seconds

Design of an Embedded System for Monitoring Devices of Elders Living Alone (독거노인 모니터링 디바이스를 위한 임베디드 시스템 설계)

  • Moon, Sang-Ook
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
    • /
    • 2010.05a
    • /
    • pp.833-835
    • /
    • 2010
  • The SPARTAN-3E development kit is equipped with an FPGA which holds 500 thousand logic gates and a bus system platform using MicroBlaze microprocessor system. This kind of embedded systems can be used to gather information from sensor nodes and send over to the main server periodically through the network gateway, using the microprocessor-based embedded system, so that edlers living alone under sensor coverage can send their moving information and can be applied to get help in the event of emergency situations. In this paper, we designed a simple embedded system based on a CPU and flash memories using such FPGAs which can be used to monitor those elderlies living alone. The developed hardware system can be directly combined with the web-based elders-living-alone monitoring system, making the system more efficient.

  • PDF

A New Multiplication Architecture for DSP Applications

  • Son, Nguyen-Minh;Kim, Jong-Soo;Choi, Jae-Ha
    • Journal of the Institute of Convergence Signal Processing
    • /
    • v.12 no.2
    • /
    • pp.139-144
    • /
    • 2011
  • The modern digital logic technology does not yet satisfy the speed requirements of real-time DSP circuits due to synchronized operation of multiplication and accumulation. This operation degrades DSP performance. Therefore, the double-base number system (DBNS) has emerged in DSP system as an alternative methodology because of fast multiplication and hardware simplicity. In this paper, authors propose a novel multiplication architecture. One operand is an output of a flash analog-to-digital converter (ADC) in DBNS format, while the other operand is a coefficient in the IEEE standard floating-point number format. The DBNS digital output from ADC is produced through a new double base number encoder (DBNE). The multiplied output is in the format of the IEEE standard floating-point number (FPNS). The proposed circuits process multiplication and conversion together. Compared to a typical multiplier that uses the FPNS, the proposed multiplier also consumes 45% less gates, and 44% faster than the FPNS multiplier on Spartan-3 FPGA board. The design is verified with FIR filter applications.

Digital Logic Extraction from QCA Designs (QCA 설계에서 디지털 논리 자동 추출)

  • Oh, Youn-Bo;Kim, Kyo-Sun
    • Journal of the Institute of Electronics Engineers of Korea SD
    • /
    • v.46 no.1
    • /
    • pp.107-116
    • /
    • 2009
  • Quantum-dot Cellular Automata (QCA) is one of the most promising next generation nanoelectronic devices which will inherit the throne of CMOS which is the domineering implementation technology for large scale low power digital systems. In late 1990s, the basic operations of the QCA cell were already demonstrated on a hardware implementation. Also, design tools and simulators were developed. Nevertheless, its design technology is not quite ready for ultra large scale designs. This paper proposes a new approach which enables the QCA designs to inherit the verification methodologies and tools of CMOS designs, as well. First, a set of disciplinary rules strictly restrict the cell arrangement not to deviate from the predefined structures but to guarantee the deterministic digital behaviors is proposed. After the gate and interconnect structures of. the QCA design are identified, the signal integrity requirements including the input path balancing of majority gates, and the prevention of the noise amplification are checked. And then the digital logic is extracted and stored in the OpenAccess common engineering database which provides a connection to a large pool of CMOS design verification tools. Towards validating the proposed approach, we designed a 2-bit adder, a bit-serial adder, and an ALU bit-slice. For each design, the digital logic is extracted, translated into the Verilog net list, and then simulated using a commercial software.

Efficient Symbol Detection Algorithm for Space-frequency OFDM Transmit Diversity Scheme (공간-주파수 OFDM 전송 다이버시티 기법을 위한 효율적인 심볼 검출 알고리즘)

  • Jung Yun ho;Kim Jae seok
    • The Journal of Korean Institute of Communications and Information Sciences
    • /
    • v.30 no.4C
    • /
    • pp.283-289
    • /
    • 2005
  • In this paper, we propose two efficient symbol detection algorithms for space-frequency OFDM (SF-OFDM) transmit diversity scheme. When the number of sub-carriers in SF-OFBM scheme is small, the interference between adjacent sub-carriers may be generated. The proposed algorithms eliminate this interference in a parallel or sequential manlier and achieve a considerable performance improvement over the conventional detection algorithm. The bit error rate (BER) performance of the proposed detection algorithms is evaluated by the simulation. In the case of 2 transmit and 2 receive antennas, at $BER=10^{-4}$ the proposed algorithms achieve the gain improvement of about 3 dB. The symbol detectors with the proposed algorithms are designed in a hardware description language and synthesized to gate-level circuits with the $0.18{\mu}m$ 1.8V CMOS standard cell library. With the division-free architecture, the proposed SF-OFDM-PIC and SF-OFDM-SIC symbol detectors can be implemented using 140k and 129k logic gates, respectively.

Implementation and verification of H.264 / AVC Intra Predictor for mobile environment (모바일 환경에서의 H.264 / AVC를 위한 인트라 예측기의 구현 및 검증)

  • Yun, Cheol-Hwan;Jeong, Yong-Jin
    • Journal of the Institute of Electronics Engineers of Korea SD
    • /
    • v.44 no.12
    • /
    • pp.93-101
    • /
    • 2007
  • Small area and low power implementation are important requirements for various multimedia processing hardware, especially for mobile environment. This paper presents a hardware architecture of H.264/AVC Intra Prediction module aiming on small area and low power. A single arithmetic unit was shared and processed sequentially for all mode decisions and computations to predict an image frame. As a result, we could get smaller area and smaller memory size compared to other existing implementations. The proposed architecture was verified using the Altera Excalibur device, and the implemented hardware has been described in Verilog-HDL and synthesized on Samsung STD130 0.18um CMOS Standard Cell Library using Synopsys Design Compiler. The synthesis result was about 11.9K logic gates and 1078 byte internal SRAM and the maximum operating frequency was 107Mhz. It consumes 879,617 clocks to process one QCIF frame, which means it can process 121.5 QCIF$(176\times144)$ frames per second, therefore it shows that it can be used for real time H.264/AVC encoding of various multimedia applications.

A High Speed FFT Processor for OFDM Systems (OFDM 시스템을 위한 고속 FFT 프로세서)

  • 조병각;손병수;선우명훈
    • Journal of the Institute of Electronics Engineers of Korea TC
    • /
    • v.39 no.12
    • /
    • pp.513-519
    • /
    • 2002
  • This paper proposes a high-speed FFT processor for orthogonal frequency-division multiplexing(OFDM) systems. The Proposed architecture uses a single-memory architecture and uses a radix-4 algorithm for high speed. The proposed memory is partitioned into four banks for high-speed computation. It uses an in-place memory strategy that stores butterfly outputs in the same memory location used by butterfly inputs. Therefore, the memory size can be reduced. The SQNR of about 80dB is achieved with 20-bit input and 20-bit twiddle factors. The architecture has been modeled by VHDL and logic synthesis has been performed using the SamsungTM 0.5㎛ SOG cell library (KG80). The implemented FFT processor consists of 98,326 gates excluding memory. It has smaller hardware than existing pipeline FFT processors for more than 1024-point FFTs. The processor can operate at 42MHz and calculate a 256-point complex FFT in 6us. It satisfies tile required processing speed of 8.4㎲ in the HomePlug standard.

A Study on the Parallel Multiplier over $GF(3^m)$ Using AOTP (AOTP를 적용한 $GF(3^m)$ 상의 병렬승산기 설계에 관한 연구)

  • Han, Sung-Il;Hwang, Jong-Hak
    • Journal of IKEEE
    • /
    • v.8 no.2 s.15
    • /
    • pp.172-180
    • /
    • 2004
  • In this paper, a parallel Input/Output modulo multiplier, which is applied to AOTP(All One or Two Polynomials) multiplicative algorithm over $GF(3^m)$, has been proposed using neuron-MOS Down-literal circuit on voltage mode. The three-valued input of the proposed multiplier is modulated by using neuron-MOS Down-literal circuit and the multiplication and Addition gates are implemented by the selecting of the three-valued input signals transformed by the module. The proposed circuits are simulated with the electrical parameter of a standard $0.35{\mu}m$CMOS N-well doubly-poly four-metal technology and a single +3V supply voltage. In the simulation result, the multiplier shows 4 uW power consumption and 3 MHzsampling rate and maintains output voltage level in ${\pm}0.1V$.

  • PDF

Design of a High-speed Decision Feedback Equalizer using the Constant-Modulus Algorithm (CMA 알고리즘을 이용한 고속 DFE 등화기 설계)

  • Jeon, Yeong-Seop;;Kim, Gyeong-Ho
    • Journal of the Institute of Electronics Engineers of Korea TC
    • /
    • v.39 no.4
    • /
    • pp.173-179
    • /
    • 2002
  • This paper describes an equalizer using the DFE (Decision Feedback Equalizer) structure, CMA (Constant Modulus Algorithm) and LMS (Least Mean Square) algorithms. The DFE structure has better channel adaptive performance and lower BER than the transversal structure. The proposed equalizer can be used for 16/64 QAM modems. We employ high speed multipliers, square logics and many CSAs (Carry Save Adder) for high speed operations. We have developed floating-point models and fixed-point models using the COSSAP$\^$TM/ CAD tool and developed VHDL filter. The proposed equalizer shows low BER in multipath fading channel. We have performed models. From the simulation results, we employ a 12 tap feedback filter and a 8 tap feedforward logic synthesis using the SYNOPSYS$\^$TM/ CAD tool and the SAMSUNG 0.5$\mu\textrm{m}$ standard cell library (STD80) and verified function and timing simulations. The total number of gates is about 130,000.

Design and Implementation of a Low-Complexity Real-Time Barrel Distortion Corrector for Wide-Angle Cameras (광각 카메라를 위한 저 복잡도 실시간 베럴 왜곡 보정 프로세서의 설계 및 구현)

  • Jeong, Hui-Seong;Kim, Won-Tae;Lee, Gwang-Ho;Kim, Tae-Hwan
    • Journal of the Institute of Electronics and Information Engineers
    • /
    • v.50 no.6
    • /
    • pp.131-137
    • /
    • 2013
  • The barrel distortion makes serious problems in a wide-angle camera employing a lens of a short focal length. This paper presents a low-complexity hardware architecture for a real-time barrel distortion corrector and its implementation. In the proposed barrel distortion corrector, the conventional algorithm is modified so that the correction is performed incrementally, which results in the reduction of the number of required hardware modules for the distortion correction. The proposed barrel distortion corrector has a pipelined architecture so as to achieve a high-throughput correction. The correction rate is 74.86 frames per sec at the operating frequency of 314MHz in a $0.11{\mu}m$ CMOS process, where the frame size is $2048{\times}2048$. The proposed barrel distortion corrector is implemented with 14.3K logic gates.

Design of ${\gamma}$=1/3, K=9 Convolutional Codec Using Viterbi Algorithm (비터비 알고리즘을 이용한 r=1/3, K=9 콘벌루션 복부호기의 설계)

  • 송문규;원희선;박주연
    • The Journal of Korean Institute of Communications and Information Sciences
    • /
    • v.24 no.7B
    • /
    • pp.1393-1399
    • /
    • 1999
  • In this paper, a VLSI design of the convolutional codec chip of code rate r=l/3, and constraint length K=9 is presented, which is able to correct errors of the received data when transmitted data is corrupted in channels. The circuit design mainly aimed for simple implementation. In the decoder, Viterbi algorithm with 3-bit soft-decision is employed. For information sequence updating and storage, the register exchange method is employed, where the register length is 5$\times$K(45 stages). The codec chip is designed using VHDL language and Design Analyzer and VHDL Simulator of Synopsys are used for simulation and synthesis. The chip is composed of ENCODER block, ALIGN block, BMC block, ACS block, SEL_MIN block and REG_EXCH block. The operation of the codec chip is verified though the logic simulations, where several error conditions are assumed. As a result of the timing simulation after synthesis, the decoding speed of 325.5Kbps is achieved, and 6,894 gates is used.

  • PDF