1) The document discusses designing an anti-aliasing filter for an analog to digital converter. It explains that the filter must be placed before the ADC to avoid aliasing from frequencies above the Nyquist rate.
2) It provides guidelines for selecting the sampling rate and filter properties based on the maximum input frequency. A higher sampling rate or steeper filter roll-off allows a simpler filter design.
3) Examples are given of digitally-controlled Sallen-Key filters on an analog input module that can be configured as 2-pole or 4-pole filters to meet anti-aliasing needs for different sampling rates. Code is provided to set the filter cutoff frequency.
1) The document discusses techniques for envelope tracking power amplifiers, including reconfigurable depth adaptive biasing, to improve linearity and efficiency.
2) Reconfigurable depth adaptive biasing modifies the current consumption of the power amplifier based on the envelope signal using a controllable gain parameter.
3) This allows balancing nonlinear distortion effects to improve linearity, with the potential for degradation if the injected envelope exceeds a threshold. Memory effects must also be considered.
The Maspro DT330 is a satellite and terrestrial tuner for Japan's ISDB digital TV services. It has a sensitive tuner and supports HDTV. Setup is easy, only requiring connection to an antenna. It automatically finds and organizes channels. However, usability could be improved as it does not support an internet connection or HD program guide. While a low-cost option, it has some annoyances like defaulting audio settings when turned off.
This document summarizes an experiment on a radio-over-fiber system for hybrid wireless-optical broadband access networks. The system used 5 GHz radio frequency signals transmitted over a 60 km fiber link using 12.5 GHz dense wavelength division multiplexing with 5 channels. Digital coherent detection and Raman amplification were used to provide enhanced power budget and reach. Bit error rate measurements showed error-free transmission was achieved after the 60 km link with and without neighboring channel interference, demonstrating the feasibility of the system for long-reach hybrid wireless-optical networks.
The Dizipia DS4H-9160 HDTV satellite receiver is a large, sturdy device with numerous connection options and powerful capabilities. It has two satellite tuners, HDMI and digital audio outputs, and supports 170+ satellites. The setup process is easy and guides the user through initial configuration. The receiver scans and organizes channels quickly, and allows customization and editing of the channel list.
The Relook 400S is a Linux-based satellite receiver with twin tuners that allows recording two channels simultaneously. It has a large channel memory, supports various DiSEqC protocols, and can be updated via USB or Ethernet. Testing found the receiver had a stable operation with clear video and audio quality, though the remote control could be more ergonomic and fan noise was sometimes noticeable.
This document discusses implementing depth of field (DOF) effects on CPUs. It begins with an introduction to DOF and techniques for generating the effect, including traditional methods like Poisson disk and Gaussian blur as well as more advanced summed area table techniques. It then demonstrates a DOF explorer application that allows comparing different DOF techniques on GPUs and with CPU offloading. Performance results are shown for various DOF techniques on Sandy Bridge processors, finding speedups from CPU offloading for advanced techniques. The document aims to showcase techniques for implementing DOF on CPUs and compare their performance to GPU implementations.
1. The document tests the Amiko SHD-8900 Alien HDTV receiver, which has the unique feature of dual boot capability, allowing it to run either the Spark or Enigma 2 operating systems.
2. Key features highlighted include its small size, stylish design, robust build quality, and extensive connection options including HDMI, USB, and Ethernet. It also has excellent tuning and channel changing speeds.
3. The document then separately evaluates the receiver's performance and capabilities when running each operating system, covering aspects like the user interface, playback of multimedia formats, recording functions, and available online features.
1) The document discusses techniques for envelope tracking power amplifiers, including reconfigurable depth adaptive biasing, to improve linearity and efficiency.
2) Reconfigurable depth adaptive biasing modifies the current consumption of the power amplifier based on the envelope signal using a controllable gain parameter.
3) This allows balancing nonlinear distortion effects to improve linearity, with the potential for degradation if the injected envelope exceeds a threshold. Memory effects must also be considered.
The Maspro DT330 is a satellite and terrestrial tuner for Japan's ISDB digital TV services. It has a sensitive tuner and supports HDTV. Setup is easy, only requiring connection to an antenna. It automatically finds and organizes channels. However, usability could be improved as it does not support an internet connection or HD program guide. While a low-cost option, it has some annoyances like defaulting audio settings when turned off.
This document summarizes an experiment on a radio-over-fiber system for hybrid wireless-optical broadband access networks. The system used 5 GHz radio frequency signals transmitted over a 60 km fiber link using 12.5 GHz dense wavelength division multiplexing with 5 channels. Digital coherent detection and Raman amplification were used to provide enhanced power budget and reach. Bit error rate measurements showed error-free transmission was achieved after the 60 km link with and without neighboring channel interference, demonstrating the feasibility of the system for long-reach hybrid wireless-optical networks.
The Dizipia DS4H-9160 HDTV satellite receiver is a large, sturdy device with numerous connection options and powerful capabilities. It has two satellite tuners, HDMI and digital audio outputs, and supports 170+ satellites. The setup process is easy and guides the user through initial configuration. The receiver scans and organizes channels quickly, and allows customization and editing of the channel list.
The Relook 400S is a Linux-based satellite receiver with twin tuners that allows recording two channels simultaneously. It has a large channel memory, supports various DiSEqC protocols, and can be updated via USB or Ethernet. Testing found the receiver had a stable operation with clear video and audio quality, though the remote control could be more ergonomic and fan noise was sometimes noticeable.
This document discusses implementing depth of field (DOF) effects on CPUs. It begins with an introduction to DOF and techniques for generating the effect, including traditional methods like Poisson disk and Gaussian blur as well as more advanced summed area table techniques. It then demonstrates a DOF explorer application that allows comparing different DOF techniques on GPUs and with CPU offloading. Performance results are shown for various DOF techniques on Sandy Bridge processors, finding speedups from CPU offloading for advanced techniques. The document aims to showcase techniques for implementing DOF on CPUs and compare their performance to GPU implementations.
1. The document tests the Amiko SHD-8900 Alien HDTV receiver, which has the unique feature of dual boot capability, allowing it to run either the Spark or Enigma 2 operating systems.
2. Key features highlighted include its small size, stylish design, robust build quality, and extensive connection options including HDMI, USB, and Ethernet. It also has excellent tuning and channel changing speeds.
3. The document then separately evaluates the receiver's performance and capabilities when running each operating system, covering aspects like the user interface, playback of multimedia formats, recording functions, and available online features.
The document summarizes a test of the C/Ku band LNB from INFOSAT. In 3 sentences:
The LNB allows reception of both C and Ku band signals with a single dish by replacing the existing Ku LNB, enabling the user to access channels from around the world without needing a second dish. Testing showed the LNB was able to receive numerous channels from satellites in both C and Ku bands, though reception depended on the signal strength which varied based on the satellite and could be improved with a larger dish. While performance was good overall, some transponders were only marginally receivable or not receivable at all using the 120cm test dish.
This paper presents an automated approach for high-quality preview rendering during lighting design for feature films. The system automatically generates a deep framebuffer and shaders from unmodified RenderMan scenes and shaders to enable interactive previews as lights are adjusted. It introduces an indirect framebuffer to efficiently handle antialiasing, motion blur, and transparency. Progressive refinement allows previews at coarse resolution with final quality after a few seconds. The system is being used in two major studios and demonstrates the approach on real-world production scenes.
IJERA (International journal of Engineering Research and Applications) is International online, ... peer reviewed journal. For more detail or submit your article, please visit www.ijera.com
This document provides information on the Panasonic AG-HMC151 memory card camera-recorder, including:
1) It records to SD memory cards in the AVCHD format and includes editing software. A 3-year warranty is also available.
2) It features functions from Panasonic's DVX100 tape-based camcorders adapted for tapeless recording, including a 28mm wide-angle lens.
3) Recording to reusable SD cards provides cost savings over tapes through reduced media, editing, and maintenance costs. This also has environmental benefits through lower power usage and less waste.
This document discusses techniques that television stations use to transmit programming feeds between stations via satellite while limiting reception to unintended viewers. These "feeds" transmit content like live sports or news reports.
The main techniques discussed are encryption, using less popular satellites that most dish owners can't receive, transmitting with specialized video formats like MPEG 4:2:2 that require professional receivers, and using very low symbol rates that most receivers can't process. The goal is to transmit content privately between stations while it is being distributed, before the final broadcast intended for households.
This document summarizes a research paper that investigates reducing peak-to-average power ratio (PAPR) in an MC-CDMA system using partial transmit sequence (PTS) technique with a suboptimal combination algorithm. The paper simulates a downlink MC-CDMA system with BPSK and QPSK modulation under varying system parameters like number of users and phase sequences. Results show the complementary cumulative distribution function (CCDF) of PAPR for the original and PTS-processed signals. Using PTS with 4, 8, or 16 phase sequences provides 1dB, 2dB, and 4.2dB of PAPR reduction respectively compared to the original signal for a 8-user BPSK modulated MC-CD
The Tape Company is a leading distributor of professional media based in Chicago with locations across the US. They offer next day delivery, valuable reward programs, the largest stock of authorized products, and competitive pricing. Their product lines include tapes from Sony, Fuji, Maxell and Panasonic for formats like HDCAM SR, DVCPRO HD, XDCAM, and P2 cards.
The document discusses various techniques for video compression, including reducing spatial, temporal, and spectral redundancy. It covers algorithms like DCT, VQ, and fractal compression. Key aspects of video compression standards like MPEG-1, MPEG-2, H.264 and techniques like motion estimation and motion compensated prediction are summarized. Current and developing video coding standards and their applications are also outlined.
The document summarizes the key features and specifications of the Panasonic AG-HMC151 memory card camera-recorder. Some of the key points include:
- It records to SD/SDHC memory cards in the AVCHD format for tapeless HD recording.
- It comes bundled with Edius Neo 2 Booster nonlinear editing software.
- It qualifies for a 3-year warranty on repairs through Panasonic's program.
- It features a 28mm wide-angle lens, 1/3" 16:9 CCD, 24p/25p/30p progressive recording, and gamma functions for creative image production.
1. The document discusses the TV Wall feature of the Spark receiver software from manufacturer Fulan, which provides an alternative to the standard channel list.
2. The TV Wall displays channel logos for up to 20 channels at a time along with an EPG and live video preview. It also allows grouping channels and searching by name.
3. Fulan provides a database of major channel logos that can be downloaded for free, and custom logos can also be added. The document provides instructions for preparing and adding custom logos.
This document discusses fiber lasers and amplifiers for applications such as environmental sensing and monitoring. It describes how lidar (light detection and ranging) uses backscattered light to determine properties of distant targets. Specifically, it focuses on using lidar for 2D/3D wind profiling applications. It provides details on lidar concepts and components, operating modes, laser requirements and characteristics, wavelengths used, and example laser systems suitable for wind profiling applications.
Introduction to Video Compression Techniques - Anurag JainVideoguy
The document provides an overview of video compression techniques and standards. It discusses the motivation for video compression to reduce data sizes for storage and transmission. It then reviews several key video compression standards including H.261, H.263, MPEG-1, MPEG-2, MPEG-4, H.264 and others. For each standard, it summarizes the goals, features, applications and technical details like motion compensation methods, block sizes, and bitrate ranges.
The Metabox HD Combo CI is an innovative HDTV receiver that can receive both satellite and terrestrial signals via DVB-S, DVB-S2, and DVB-T. It is the first receiver to combine these two reception modes into one box. The receiver has an easy-to-use interface and features multiple tuners, HDMI output, and the ability to store up to 10,000 channels. It also supports software updates and comes with a comprehensive EPG. The Metabox HD Combo CI provides a convenient solution for receiving both local terrestrial channels and satellite TV with one receiver.
The document provides a review of the Topfield TMS SRP-2100 receiver. It summarizes that the receiver combines satellite television and internet capabilities. It features a new chipset that supports high-definition DVB-S2 and H.264 signals. The receiver has a touch-sensitive front panel with LED lighting and hides two CI slots and two USB ports behind a flap. Connections on the back include HDMI, scart, and RCA ports.
This document discusses optimal selection of binary codes for pulse compression in surveillance radar. It describes how pulse compression allows radar to achieve high range resolution while maintaining high signal energy by modulating a long pulse. Binary phase coding is discussed as a method for pulse compression where a long pulse is divided into sub-pulses that are coded with either 0 or pi phase shifts according to a binary sequence. The autocorrelation properties of different binary codes impact the performance of pulse compression radar. The document aims to compare binary codes through simulation of their autocorrelation functions to identify the most optimal code for surveillance applications.
This document presents a generalized discrete cosine transform (DCT) decimation scheme for DCT-domain spatial downscaling to improve visual quality. It proposes performing two-fold decimation on flexible-sized subframes larger than 8x8 blocks to reduce aliasing artifacts compared to pixel-domain downscaling schemes. Sparse matrix representations are derived to reduce the computation cost of the proposed DCT decimation method. Experimental results show the proposed approach achieves better visual quality than existing schemes while computational complexity increases but can be optimized by applying larger subframe sizes only to high activity regions.
The document discusses video technology including analogue and digital video. It explains that analogue video uses continuously varying electrical signals to represent brightness and color, while digital video represents this information using discrete binary numbers. The document also covers video concepts such as frame rate, resolution, compression methods, and standards for analogue television like NTSC, PAL, and SECAM.
It's my ppt of disseration defense at 2012_06_04. Please give me some feedback so I can improve my ppt skills. Feel free to discuss any problem with me. Thank you!
The document discusses different types of video compression standards including MPEG, H.261, H.263, and JPEG. It explains key concepts in video compression like frame rate, color resolution, spatial resolution, and image quality. MPEG standards like MPEG-1, MPEG-2, MPEG-4, and MPEG-7 are defined for compressing video and audio at different bit rates. Techniques like spatial and temporal redundancy reduction are used to compress video frames and consecutive frames. Compression reduces file sizes but can cause data loss during transmission.
This document summarizes techniques for core allocation and relocation management in self-dynamically reconfigurable architectures. It introduces basic concepts like cores, IP cores, and reconfigurable regions. It then describes proposed 1D and 2D relocation solutions like BiRF and BiRF Square that allow runtime relocation with low overhead. A core allocation manager is introduced to choose core placements optimizing criteria like rejection rate and completion time with low management costs. Evaluation shows the techniques improve metrics like rejection rate and routing costs compared to other approaches.
This document discusses an FPGA implementation of a four phase code design using a modified genetic algorithm. It summarizes the key aspects of the implementation as follows:
1) The proposed architecture efficiently implements a modified genetic algorithm on an FPGA to identify good pulse compression sequences based on discrimination factor.
2) Pulse compression techniques in radar allow long pulses to achieve high energy while maintaining the range resolution of short pulses. The receiver compresses the long signal into a narrow signal.
3) The criteria for good pulse compression sequences include high merit factor and discrimination factor. Merit factor measures quality by comparing main lobe energy to side lobe energy. Discrimination factor compares the main peak to maximum side lobes.
A Coarse-Grained Reconfigurable Wavelet Denoiser Exploiting the Multi-Dataflo...MDC_UNICA
In the last few years, efficient resource management turned out to be one of the major challenges for hardware designers. Strategies of reusability through reconfiguration have demonstrated interesting potentials to address it, providing also power and area minimization. The Multi-Dataflow Composer (MDC) tool has been presented to the scientific community to automatically build-up runtime coarse-grained reconfigurable platforms. Originally conceived in the field of Reconfigurable Video Coding (RVC), the MDC allows achieving attractive results also for hardware designers operating in different application fields. In this work, we intend to demonstrate the potential orthogonality of the MDC approach with respect to the RVC domain. A runtime reconfigurable wavelet denoiser, targeted for biomedical applications, has been developed and prototyped onto an FPGA Development Board Spartan 3E 1600. Impressive results in terms of resource minimization have been achieved with respect to more traditional solutions.
The document summarizes a test of the C/Ku band LNB from INFOSAT. In 3 sentences:
The LNB allows reception of both C and Ku band signals with a single dish by replacing the existing Ku LNB, enabling the user to access channels from around the world without needing a second dish. Testing showed the LNB was able to receive numerous channels from satellites in both C and Ku bands, though reception depended on the signal strength which varied based on the satellite and could be improved with a larger dish. While performance was good overall, some transponders were only marginally receivable or not receivable at all using the 120cm test dish.
This paper presents an automated approach for high-quality preview rendering during lighting design for feature films. The system automatically generates a deep framebuffer and shaders from unmodified RenderMan scenes and shaders to enable interactive previews as lights are adjusted. It introduces an indirect framebuffer to efficiently handle antialiasing, motion blur, and transparency. Progressive refinement allows previews at coarse resolution with final quality after a few seconds. The system is being used in two major studios and demonstrates the approach on real-world production scenes.
IJERA (International journal of Engineering Research and Applications) is International online, ... peer reviewed journal. For more detail or submit your article, please visit www.ijera.com
This document provides information on the Panasonic AG-HMC151 memory card camera-recorder, including:
1) It records to SD memory cards in the AVCHD format and includes editing software. A 3-year warranty is also available.
2) It features functions from Panasonic's DVX100 tape-based camcorders adapted for tapeless recording, including a 28mm wide-angle lens.
3) Recording to reusable SD cards provides cost savings over tapes through reduced media, editing, and maintenance costs. This also has environmental benefits through lower power usage and less waste.
This document discusses techniques that television stations use to transmit programming feeds between stations via satellite while limiting reception to unintended viewers. These "feeds" transmit content like live sports or news reports.
The main techniques discussed are encryption, using less popular satellites that most dish owners can't receive, transmitting with specialized video formats like MPEG 4:2:2 that require professional receivers, and using very low symbol rates that most receivers can't process. The goal is to transmit content privately between stations while it is being distributed, before the final broadcast intended for households.
This document summarizes a research paper that investigates reducing peak-to-average power ratio (PAPR) in an MC-CDMA system using partial transmit sequence (PTS) technique with a suboptimal combination algorithm. The paper simulates a downlink MC-CDMA system with BPSK and QPSK modulation under varying system parameters like number of users and phase sequences. Results show the complementary cumulative distribution function (CCDF) of PAPR for the original and PTS-processed signals. Using PTS with 4, 8, or 16 phase sequences provides 1dB, 2dB, and 4.2dB of PAPR reduction respectively compared to the original signal for a 8-user BPSK modulated MC-CD
The Tape Company is a leading distributor of professional media based in Chicago with locations across the US. They offer next day delivery, valuable reward programs, the largest stock of authorized products, and competitive pricing. Their product lines include tapes from Sony, Fuji, Maxell and Panasonic for formats like HDCAM SR, DVCPRO HD, XDCAM, and P2 cards.
The document discusses various techniques for video compression, including reducing spatial, temporal, and spectral redundancy. It covers algorithms like DCT, VQ, and fractal compression. Key aspects of video compression standards like MPEG-1, MPEG-2, H.264 and techniques like motion estimation and motion compensated prediction are summarized. Current and developing video coding standards and their applications are also outlined.
The document summarizes the key features and specifications of the Panasonic AG-HMC151 memory card camera-recorder. Some of the key points include:
- It records to SD/SDHC memory cards in the AVCHD format for tapeless HD recording.
- It comes bundled with Edius Neo 2 Booster nonlinear editing software.
- It qualifies for a 3-year warranty on repairs through Panasonic's program.
- It features a 28mm wide-angle lens, 1/3" 16:9 CCD, 24p/25p/30p progressive recording, and gamma functions for creative image production.
1. The document discusses the TV Wall feature of the Spark receiver software from manufacturer Fulan, which provides an alternative to the standard channel list.
2. The TV Wall displays channel logos for up to 20 channels at a time along with an EPG and live video preview. It also allows grouping channels and searching by name.
3. Fulan provides a database of major channel logos that can be downloaded for free, and custom logos can also be added. The document provides instructions for preparing and adding custom logos.
This document discusses fiber lasers and amplifiers for applications such as environmental sensing and monitoring. It describes how lidar (light detection and ranging) uses backscattered light to determine properties of distant targets. Specifically, it focuses on using lidar for 2D/3D wind profiling applications. It provides details on lidar concepts and components, operating modes, laser requirements and characteristics, wavelengths used, and example laser systems suitable for wind profiling applications.
Introduction to Video Compression Techniques - Anurag JainVideoguy
The document provides an overview of video compression techniques and standards. It discusses the motivation for video compression to reduce data sizes for storage and transmission. It then reviews several key video compression standards including H.261, H.263, MPEG-1, MPEG-2, MPEG-4, H.264 and others. For each standard, it summarizes the goals, features, applications and technical details like motion compensation methods, block sizes, and bitrate ranges.
The Metabox HD Combo CI is an innovative HDTV receiver that can receive both satellite and terrestrial signals via DVB-S, DVB-S2, and DVB-T. It is the first receiver to combine these two reception modes into one box. The receiver has an easy-to-use interface and features multiple tuners, HDMI output, and the ability to store up to 10,000 channels. It also supports software updates and comes with a comprehensive EPG. The Metabox HD Combo CI provides a convenient solution for receiving both local terrestrial channels and satellite TV with one receiver.
The document provides a review of the Topfield TMS SRP-2100 receiver. It summarizes that the receiver combines satellite television and internet capabilities. It features a new chipset that supports high-definition DVB-S2 and H.264 signals. The receiver has a touch-sensitive front panel with LED lighting and hides two CI slots and two USB ports behind a flap. Connections on the back include HDMI, scart, and RCA ports.
This document discusses optimal selection of binary codes for pulse compression in surveillance radar. It describes how pulse compression allows radar to achieve high range resolution while maintaining high signal energy by modulating a long pulse. Binary phase coding is discussed as a method for pulse compression where a long pulse is divided into sub-pulses that are coded with either 0 or pi phase shifts according to a binary sequence. The autocorrelation properties of different binary codes impact the performance of pulse compression radar. The document aims to compare binary codes through simulation of their autocorrelation functions to identify the most optimal code for surveillance applications.
This document presents a generalized discrete cosine transform (DCT) decimation scheme for DCT-domain spatial downscaling to improve visual quality. It proposes performing two-fold decimation on flexible-sized subframes larger than 8x8 blocks to reduce aliasing artifacts compared to pixel-domain downscaling schemes. Sparse matrix representations are derived to reduce the computation cost of the proposed DCT decimation method. Experimental results show the proposed approach achieves better visual quality than existing schemes while computational complexity increases but can be optimized by applying larger subframe sizes only to high activity regions.
The document discusses video technology including analogue and digital video. It explains that analogue video uses continuously varying electrical signals to represent brightness and color, while digital video represents this information using discrete binary numbers. The document also covers video concepts such as frame rate, resolution, compression methods, and standards for analogue television like NTSC, PAL, and SECAM.
It's my ppt of disseration defense at 2012_06_04. Please give me some feedback so I can improve my ppt skills. Feel free to discuss any problem with me. Thank you!
The document discusses different types of video compression standards including MPEG, H.261, H.263, and JPEG. It explains key concepts in video compression like frame rate, color resolution, spatial resolution, and image quality. MPEG standards like MPEG-1, MPEG-2, MPEG-4, and MPEG-7 are defined for compressing video and audio at different bit rates. Techniques like spatial and temporal redundancy reduction are used to compress video frames and consecutive frames. Compression reduces file sizes but can cause data loss during transmission.
This document summarizes techniques for core allocation and relocation management in self-dynamically reconfigurable architectures. It introduces basic concepts like cores, IP cores, and reconfigurable regions. It then describes proposed 1D and 2D relocation solutions like BiRF and BiRF Square that allow runtime relocation with low overhead. A core allocation manager is introduced to choose core placements optimizing criteria like rejection rate and completion time with low management costs. Evaluation shows the techniques improve metrics like rejection rate and routing costs compared to other approaches.
This document discusses an FPGA implementation of a four phase code design using a modified genetic algorithm. It summarizes the key aspects of the implementation as follows:
1) The proposed architecture efficiently implements a modified genetic algorithm on an FPGA to identify good pulse compression sequences based on discrimination factor.
2) Pulse compression techniques in radar allow long pulses to achieve high energy while maintaining the range resolution of short pulses. The receiver compresses the long signal into a narrow signal.
3) The criteria for good pulse compression sequences include high merit factor and discrimination factor. Merit factor measures quality by comparing main lobe energy to side lobe energy. Discrimination factor compares the main peak to maximum side lobes.
A Coarse-Grained Reconfigurable Wavelet Denoiser Exploiting the Multi-Dataflo...MDC_UNICA
In the last few years, efficient resource management turned out to be one of the major challenges for hardware designers. Strategies of reusability through reconfiguration have demonstrated interesting potentials to address it, providing also power and area minimization. The Multi-Dataflow Composer (MDC) tool has been presented to the scientific community to automatically build-up runtime coarse-grained reconfigurable platforms. Originally conceived in the field of Reconfigurable Video Coding (RVC), the MDC allows achieving attractive results also for hardware designers operating in different application fields. In this work, we intend to demonstrate the potential orthogonality of the MDC approach with respect to the RVC domain. A runtime reconfigurable wavelet denoiser, targeted for biomedical applications, has been developed and prototyped onto an FPGA Development Board Spartan 3E 1600. Impressive results in terms of resource minimization have been achieved with respect to more traditional solutions.
On the Performance Analysis of Multi-antenna Relaying System over Rayleigh Fa...IDES Editor
In this work, the end-to-end performance of an
amplify-and-forward multi-antenna infrastructure-based relay
(fixed relay) system over flat Rayleigh fading channel is
investigated. New closed form expressions for the statistics of
the received signal-to-noise ratio (SNR) are presented and
applied for studying the outage probability and the average
bit error rate of the digital receivers. The results reveal that
the system performance improves significantly (roughly 3 dB)
for M=2 over that for M=1 in both low and high signal-tonoise
ratio. However, little additional performance
improvement can be achieved for M>2 relative to M=2 at high
SNR.
The document analyzes the performance of LDPC coded WLAN physical layer under BPSK and 16-QAM modulation. It finds that an LDPC encoded WLAN system with a code rate of (48,46) performs best under BPSK modulation in an AWGN channel, achieving the lowest bit error rate. Simulation results show LDPC coding improves performance by reducing bit error rates compared to without coding. The best performing configuration provides power efficiency through lower transmitted power requirements for a given bit error rate.
FPGA Based Design of High Performance Decimator using DALUT AlgorithmIDES Editor
This paper presents a multiplier less approach
to implement high speed and area efficient decimator for
down converter of Software Defined Radios. This
technique substitutes multiply-and-accumulate (MAC)
operations with look up table (LUT) accesses. Proposed
decimator has been implemented using Partitioned
distributed arithmetic look up table (DALUT) algorithm
by taking optimal advantage of embedded LUTs of target
FPGA device. This method is useful to enhance the system
performance in terms of speed and area. The proposed
decimator has used half band polyphase decomposition
FIR structure. The decimator has been designed with
Matlab 7.6, simulated with Modelsim 6.3XE simulator,
synthesized with Xilinx Synthesis Tool (XST) 10.1 and
implemented on Spartan-3E based 3s500efg320-4 FPGA
device. The proposed DALUT approach has shown an
improvement of 24% in speed by saving almost 50%
resources of target device as compared to MAC based
approach.
Design And Performance of Finite impulse Response Filter Using Hyperbolic Cos...IDES Editor
In this paper a proposed of design and analysis of
Finite impulse response filter using Hyperbolic Cosine
window (Cosh window for short). This window is very useful
for some applications such as beam forming, filter design,
and speech processing. Digital FIR filter designed by Kaiser
window has a better far-end stop-band attenuation than filter
designed by the other previously well known adjustable
windows such as Dolph-Chebyshev and Saramaki, which are
special cases of Ultraspherical windows, but obtaining a digital
filter which performs higher far-end stop band attenuation
than Kaiser window will be useful. In this paper, the design of
nonrecursive digital FIR filter has been proposed by using
Cosh window. It provides better side lobe roll-off ratio & farend
stop band attenuation than filter designed by well known
Kaiser window, which is the advantage of filter designed by
Cosh window over filter designed by Kaiser window. An
expression for the side lobe & far field level has been developed.
Simulation & experimental results showing a good agreement
with theory has been provided
A Noise Reduction Method Based on Modified Least Mean Square Algorithm of Rea...IRJET Journal
This document presents a modified least mean square (LMS) algorithm to reduce noise in real-time speech signals. The proposed approach modifies the standard LMS algorithm by incorporating a Wiener filter. Experiments are conducted on speech samples from the NOIZEUS database with various types of noise at different signal-to-noise ratios. Objective measures like segmental SNR, log likelihood ratio, Itakura-Saito spectral distance, and cepstrum are used to evaluate the performance of the proposed algorithm compared to the standard LMS algorithm. The results show that the modified LMS algorithm with Wiener filter outperforms the standard LMS algorithm in enhancing the quality of noisy speech signals based on the objective measure values.
This document summarizes several sensor projects being conducted by EPRI related to transmission lines, underground transmission, and substations. It lists projects assessing transmission line sensors, developing sensors for conductor condition, fault currents, image processing, insulator leakage currents, and vibrations. It also describes projects creating sensors for oil pressure in underground transmission, 3D acoustic emission transformer monitoring, assessing substation sensors, monitoring geomagnetically induced currents, and wirelessly monitoring load tap changers and acoustic emissions. The document provides high-level overviews of these various sensor technologies and applications.
1. This document provides an A-Z glossary of terms related to digital photography.
2. Entries include definitions of technical terms like analog, digital, pixel, and compression as well as descriptions of camera components and features such as aperture, autofocus, battery, and memory cards.
3. The glossary also covers digital imaging concepts and processes including color depth, downloading, printing, and file formats.
This document summarizes a research paper on developing efficient neural network architectures for universal audio source separation. The proposed model, called SuDoRM-RF, uses successive downsampling and resampling of multi-resolution features to extract information from multiple temporal scales with fewer computations. Experimental results show that SuDoRM-RF achieves comparable or better source separation performance than state-of-the-art models while requiring significantly fewer computational resources in terms of FLOPs, memory usage, and training time. Improved and causal variants of SuDoRM-RF are also proposed to further reduce parameters and enable real-time processing.
This document discusses real-time embedded acoustic DSP projects. It begins by describing the objective of creating audio special effects using DSP algorithms. It then discusses the technologies applied, including the hardware used which is a TMS320C6713 DSK and the Code Composer Studio software. The core of the document discusses the theory behind building blocks like comb filters, all-pass filters, and notch filters that are used to create effects like echo, flanging, chorus, phasing, reverb, tremolo, and more. It concludes by discussing considerations for real-time embedded DSP applications using the TMS320C6713 architecture.
Welcome to International Journal of Engineering Research and Development (IJERD)IJERD Editor
This document discusses the design and analysis of multirate filters for WiMAX applications. It proposes a programmable multirate filter architecture that can be implemented using software-defined radio technology and multirate signal processing principles. The filters are designed using MATLAB's filter design and analysis tool to meet WiMAX specifications. A digital upconverter is presented that uses three cascaded FIR filters with interpolation factors of 1, 2, and 4 to achieve an overall interpolation factor of 8 as required by WiMAX. The filters are analyzed and simulated in MATLAB to verify they satisfy WiMAX's spectral mask requirements.
This document compares techniques for reducing out-of-band interference in OFDM systems, including carrier nulling, windowing, and active interference cancellation (AIC). It implements these techniques in MATLAB and analyzes their effectiveness in lowering interference levels. Specifically, it shows that AIC provides the most interference suppression but results in power peaks as the number of AIC tones increases. To address this, the document proposes incorporating an optimization technique to restore power levels when varying the number of AIC tones.
The document discusses beamforming antennas and their applications. It begins by outlining beamforming concepts and configurations like phased arrays and adaptive arrays. It then discusses applications of beamforming antennas in areas like radar, sonar, communications and imaging. Specific examples covered include phased array radar, neuronal spike sorting, and smart antenna systems for wireless networks. Vector antennas and their advantages over phased arrays are also summarized. Finally, the document discusses potential uses and challenges of beamforming antennas for wireless ad hoc networks.
The LaserSCANNER is a VESDA air sampling smoke detector that can divide its detection area into four separate sectors. It draws air from all sectors and uses a laser to quickly scan and identify which sector is carrying smoke during an alarm. It has adjustable alarm thresholds for each sector to optimize detection. Key features include individual sector identification and monitoring, adaptive scanning, VESDAnet communication, and software for automatic setup and environmental compensation.
IFKSA-ESPRIT - Estimating the Direction of Arrival under the Element Failures...IDES Editor
This paper presents the use of Inverse Free Krylov
Subspace Algorithm (IFKSA) with Estimation of Signal
Parameters via Rotational Invariance Technique (ESPRIT)
for the Direction-of-Arrival (DOA) estimation under element
failure in a Uniform Linear Antenna Array (ULA). Failure of
a few elements results in sparse signal space. IFKSA algorithm
is an iterative algorithm to find the dominant eigenvalues
and is applied for decomposition of sparse signal space, into
signal subspace and the noise subspace. The ESPRIT is later
used to estimate the DOAs. The performance of the algorithm
is evaluated for various elements failure scenarios and noise
levels, and the results are compared with ESPRIT and Cramer
Rao Lower bound (CRLB). The results indicate a better
performance of the IFKSA-ESPRIT based DOA estimation
scheme under different antenna failure scenarios, and noise
levels.
The document proposes a new signaling technique called Auto-Correlated Optical OFDM (ACO-OFDM) for free space optical communications based on bit error rate. ACO-OFDM uses the autocorrelation of frequency coefficients to generate signals directly without constraining modulation bandwidth, ensuring non-negativity. Simulation results show that ACO-OFDM has better bit error rate performance compared to existing techniques like DC-biased OFDM and Asymmetrically Clipped Optical OFDM.
Similar to eTech 6 - Connecting the analouge world to RS EDP (20)
RS has over 500,000 products for design, research, and development needs. The document is a product guide for electronics that introduces RS's commitment to providing customers with high-quality product offerings and service. It highlights some of the electronic product categories and brands available from RS to support customers' design needs.
Version 2 of DesignSpark PCB adds several new features, most notably a 3D viewer that allows engineers to visualize their PCB design in 3D. It has also improved usability with enhanced rotation and library management capabilities. Over 60,000 downloads have been made since its launch 9 months ago, showing its growing popularity among engineers from over 150 countries.
1. The Rapid Power System (RPS) is a new concept in power system design that allows product designers to implement a custom multi-rail power supply early in development.
2. The RPS provides a main 12Vdc rail and four user pluggable module zones, allowing up to five DC output rails totaling 60W. It monitors voltage, current, power, efficiency and temperature on each rail.
3. Testing an external hard disk drive with the RPS provided detailed power consumption data, showing peak startup power of 32W lasting 5 seconds and steady state power of 10W. Analysis of rail power revealed opportunities to reduce power during disk inactivity.
eTech 6 - Networker - an advanced web server with a microRS Components Malta
Here are 3 tips for designing a microcontroller network: 1) Use a microcontroller with an advanced web server capability to allow networking and remote access/control, 2) Include voltage regulators to supply stable power to the microcontroller from the network or power source, 3) Add status LEDs connected to I/O pins to provide visual feedback on the operation and connectivity of the network.
This document discusses open source hardware (OSHW) and its growth from a niche phenomenon to a multi-million dollar industry. It notes that OSHW projects make hardware design files and documentation available with liberal licenses, allowing anyone to study, modify, and distribute designs. The Arduino microcontroller is cited as the poster child of OSHW due to its success stemming from its open and collaborative development model that has fostered a large ecosystem and global support community.
eTech 6 - How unlocking information from a fan is a blastRS Components Malta
1) Communicating with electronically commutated (EC) fans allows users to access vital information for optimizing system performance and preventing downtime through closed-loop speed control and condition monitoring.
2) EC fans contain onboard electronics that support the RS-485 and Modbus RTU communication protocols, enabling two-way communication for fan speed control, monitoring, and fault detection.
3) Collecting operating data from fans through communication protocols helps maintenance personnel implement predictive maintenance and avoid costly downtime by detecting potential issues early.
The use of additional visual or audio feedback can compensate for the reduction in tactile response from newer human-machine interfaces. Changes in lighting or synthesized click sounds provide feedback to users where the tactile feedback of older mechanical interfaces is absent. Membrane keypads and touchscreens demonstrate that usability does not require tactile feedback, as long as the system response is consistent and immediate.
The document discusses connectivity technologies and how they enable new functionality. It introduces several connectivity topics that are featured in the issue, including USB 3.0, ZigBee mesh networking, Power over Ethernet, and human-machine interfaces. The goal of RS Components is to help customers find the right connectivity solutions for their projects and provide components to support prototyping and production. An interactive iPad app has been created to deliver enhanced content for eTech magazine.
This document provides a selection of over 400 star products and offers that are ready for fast delivery from www.rs-components.com. It includes a wide range of products across applications to meet various needs. Customers can also find 500,000 additional products online and always with the trusted reliability of RS Service.
The document discusses how electronic circuit breakers from E-T-A helped reduce downtime on production lines at a Nissan automobile plant. Specifically, installing E-T-A's ESS20 electronic circuit breakers on circuits powered by 24V switch-mode power supplies reduced wiring fault downtime by 75% on one line and 50-70% on another line by enabling selective protection and isolation of faulty circuits from the power supply. This minimized disruption when faults occurred.
The article discusses the future of user interfaces, focusing on the growth of touch interfaces and optical sensing technologies. Touch interfaces are becoming more sophisticated, moving from simple touch to multi-touch capabilities. Optical sensing allows for touchless interfaces using 3D mapping and gesture recognition. These consumer-oriented technologies could inspire new generations of intuitive, productive interfaces for industrial and professional equipment.
The document is an issue of an electronics magazine published by RS Components. It highlights several topics, including:
1) RS Components' new online Electronics Centre and upgrade to help customers complete designs more quickly. It also details a partnership between RS, ARM and mbed to support ARM's virtual design environment.
2) Technical articles on renewable energy sources like solar power and low-power communication, processor, connector, and display technologies.
3) New products including over 4,000 additional Tyco Electronics connector lines and energy-saving lighting products from RS light Energy.
The magazine seeks feedback from readers on technical articles and ideas.
The document discusses new online design resources launched by RS Components to help engineers. It introduces Component Chooser, a new parametric search tool that allows intuitive searching and comparison of over 260,000 electronic components. It also discusses the availability of downloadable 3D CAD models of over 20,000 products. Finally, it mentions DesignSpark, a new website providing design tools, reviews and industry discussion to simplify and accelerate the design process.
eTEch 5 - Balancing the Power Options.
Explore the latest issue and find out about Power efficiency for the modern electronics system, Fibre optic choices for today's energy challenges and ESD protection.
Want a hard copy of eTech 5
request one at rssales@tccmalta.com and we will send one right away.
RS Components has renewed its focus on keeping its electronic components and test equipment offerings up to date. It has added over 5,000 new products per month and reduced prices on 165,000 existing products. It has also redesigned its quarterly magazine, now called eTech, to provide more relevant content. RS aims to be a comprehensive source for the latest technologies, components, industries and tools through its supplier-agnostic approach and strengthened product management team with semiconductor expertise. Customers are encouraged to provide feedback to help shape eTech's coverage of significant technologies, products and information.
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Paper Link: https://eprint.iacr.org/2024/257
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eTech 6 - Connecting the analouge world to RS EDP
1. DESIGN DESIGN
REVIEW REVIEW
CONNECTING
Design considerations for the Programming the Digital Potentiometers Resources
anti-aliasing filter The potentiometers are programmed from an [1] Software drivers for the AN16 module
The frequency plots in Fig.1 provide a I2C serial bus with two allocated to each filter together with full code listings of sample
ThE aNalOGUE
graphical representation of aliasing. In this controlling the resistive components which set programs can be downloaded from the EDP
example we are going to sample a signal the cut-off frequency. [1] Advantage is taken Design Centre on the DesignSpark website at:
which has a maximum frequency component of a simplification of the Sallen-Key filter which http://www.designspark.com/design-centre.
of fmax (the band in green) using a sampling occurs when the two resistances and two
WORlD TO
frequency of fs. The plot on the left shows capacitances are in the ratio 2 to 1. [2] [2] Analysis of the Sallen-Key Architecture, TI
all the new frequencies present in the non- Application Report, SLOA024B.
aliased sampled signal. Note that we now
RS EDP
have new bands of frequencies (in blue) each
with a width of 2 x fmax and centred on the Share your views on this article
sampling frequency ƒs and its harmonics. This at www.designspark.com
is a correctly sampled signal because fs > 2 x
fmax. By contrast the plot on the right shows
extensive aliasing where the various bands
overlap leading to the production of erroneous
frequencies in the green baseband. dB
analogue Input module: Setting up the anti-aliasing filter 0 2-Pole Filters, AN0 or AN1
The practical problem is that few ‘raw’ signals Roll-off = -40dB/decade
have a nice, clean fmax. In order to avoid
aliased components being produced, a low- -
Get the Specification pass anti-aliasing filter needs to be placed in 20
4-Pole Filter, AN0 + AN1
circuit before the ADC. Roll-off = -80dB/decade
Before the considering the analogue input f > 2f : No aliasing f < 2f : aliasing
S max S max
to a digital system, the designer must have -
available a certain amount of numerical data: Fig.2 shows the trade-off between sampling 40
Signal Power Signal Power rate and the order of the low-pass filter. The
• The maximum frequency component of Aliased Frequencies designer can massively over-sample and then -
the analogue signal use a simple low-order filter or select a lower 60
rate and then be faced with the need for a
• The Dynamic Range of the analogue complex multi-pole type. However the ability
signal (ratio of the maximum to the of the DSP device to process the algorithm
minimum input signal level) between consecutive samples must be 100 1000 10000 100000 1000000 f Hz
• The required Signal-to-Noise ratio of the considered before the sampling rate is set. Filter cut-off range
digitized signal It can save a lot of trouble later if the DSP AN0 or AN1
program is tested and timed on a suitable
fig. 3 frequency response of digitally-controlled filters on aN0 and aN1
development system before the sampling rate
The first point is what concerns us here when is fixed and the filter designed.
deciding on the cut-off frequency of the input fig.1 aliasing
analogue low-pass-filter. anti-aliasing filters on the analogue
Input module (EDP-am-aN16)
Signal Power
Decide on the sampling rate Sampling rate mUCh greater than Nyquist Sallen-Key filters are used on the Analogue
The sampling rate is set according to the Input module which provides filter circuits for
Nyquist criterion which states that it must be up to 16 input channels. Eight have simple
Lower Order, shallow roll-off LPF required Rf = 6772556u/Fcut_off; /* Calculate filter R2 resistor value */
at least twice that of the maximum frequency passive 1-pole filters, six have fixed cut-off R2_Pot = 12000u*Rf/(12000u-Rf); /* Digital pot in parallel with 12k resistor */
component present in the analogue signal. This (12kHz) 2-pole Sallen-Key filters with a roll-off R1_Pot = R2_Pot/2u; /* R1 resistor value = R2/2 */
ensures accurate reproduction of the signal, of -40dB/decade and two have 2-pole filters
but a much higher rate will ease the design whose cut-off frequency can be set by digital Set_resistance(1u,R1_Pot); /* Call AN16 driver and set Pot channel 1 */
of a vital circuit that precedes the ADC: potentiometers. These two filters on channels Set_resistance(2u,R2_Pot); /* Call AN16 driver and set Pot channel 2 */
the Anti-Aliasing filter. AN0 and AN1 can be cascaded by means of
Signal Power a solder-link to provide a single 4-pole filter on
AN0 with -80dB/decade roll-off. listing 1. C code for calculating the aN0 filter resistance values
Sampling rate JUST greater than Nyquist
High Order, steep roll-off LPF required
Get more online...
fig.2 Designing the anti-aliasing filter: Cut-off and Roll-off See the latest on EDP at www.designspark.com/theme/rs-edp
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