Analog Transmission Research Articles

A 5-6.4-Gb/s 12-channel transceiver with pre-emphasis and equalization

A 5-6.4 Gb/s transceiver, consisting of a parallel 12-channel transmitter (Tx), 12-channel receiver (Rx), clock generators based on LC-VCO phase-locked loops (PLLs), and a clock recovery unit, was developed. The Tx has a five-tap pre-emphasis filter, and the Rx has an equalizer with an intersymbol interference (ISI) monitor. Monitoring the ISI enables fine adjustment of loss compensation. The pre-emphasis filter in the Tx and the equalizer in the Rx compensate for transmission losses of up to 20 dB at 6.4 Gb/s, respectively. Both the Tx and Rx channels, including the PLLs, are 3.92 mm/sup 2/ in area. The transmitter dissipates 150 mW/channel at 6.4 Gb/s when compensating for a loss of 20 dB, and the receiver 90 mW/channel when compensating for the same loss.

Performance of Centrifuge Data Acquisition Systems Using Wireless Transmission

Abstract Centrifuge testing requires transmitting data collected in a moving, increased-acceleration environment to a data acquisition system. Typical transmission methods include analog and digital data transmission through slip rings. However, these methods have often limited the accuracy of the measured data as well as the number of instruments that can be used in a test. A wireless ethernet data acquisition system was implemented for a centrifuge in this study. Using a computer equipped with a wireless ethernet card inside the centrifuge allows increased throughput while maintaining control of the centrifuge test by an external computer. Such a computer workgroup connected with wireless ethernet provides high throughput of noiselessly transmitted data. This approach allows a significant increase in the number of channels, and thus instruments, that can be used in a test when compared with other digital communication standards. An evaluation of the performance of this system indicates that the data throughput of the wireless system is consistently higher than conventional hard-wired serial communication systems, but depends on the g-level, transmission direction, and type of wireless card.

Investigation and optimisation of a multipass resonant photoacoustic cell at high absorption levels

A theoretical and experimental investigation of photoacoustic (PA) signals in a resonant multipass PA cell with high background absorption (up to 29 m-1) is presented. An analogous electric transmission line model including discontinuity inductances at cross section changes was used to model the first longitudinal acoustic mode of the multipass PA cell equipped with two buffer volumes. This model was validated with experimentally obtained results and used to predict the behaviour of the PA cell for different multipass arrangements and different buffer volume diameters. The highest PA signal is obtained for high pass number and large buffer radius. Increasing the absorption coefficient of the medium enhances the PA signal until a maximum is reached, leading to a minimum for the PA signal sensitivity. For a given background absorption, the number of passes required to maximise the sensitivity depends on the absorption coefficient. The model allows the determination of the best-suited number of passes for a given absorption coefficient and cell geometry.

Optical wireless links with enhanced linearity and selectivity [Invited

Feature Issue on Optical Wireless Communications (OWC) Optical wireless is an attractive medium as an alternative to optical fiber communications, and also to RF, because of its high bandwidth and relative ease of use, especially when it comes to deployment in new physical situations. We describe an optical wireless link approach that offers a performance that gives analog transmission with significantly reduced distortion levels and enhanced reception sensitivity by combining a novel hybrid detector-amplifier technique. Reduction of distortion by 40 dB and improvement in sensitivity of 20-30 dB is possible, using the techniques described.

Speech encryption system with a low bit rate coding algorithm for analogue transmission line

Speech encryption system with a low bit rate coding algorithm for analogue transmission line

Network-based fire-detection system via controller area network for smart home automation

This paper presents a network-based fire-detection system via the controller area network (CAN) to evaluate the feasibility of using such a home automation protocol in a smart home. In general, a conventional fire-detection system has several shortcomings, such as weakness to noise, because it uses an analog transmission with 4-20 mA current lines. Hence, as an alternative to the conventional system, this paper describes the structure of a CAN-based fire-detection system and the design method of a CAN communication network. The performance of the proposed system is evaluated through experimental tests. The CAN has several advantages, such as low cost and ease of implementation, as compared to the other low layers of the BACNet, such as Ethernet or ARCNET. Therefore, if the CAN is selected for the low layer of the BACNet, a home automation system can be implemented more effectively.

Galvanically isolated and linear transmission of analog current-signals using the optically coupled current–mirror architecture

We describe a novel circuit architecture, the optically coupled current-mirror (OCCM), that allows linear transmission of analog current signals over optical fibers. The OCCM ensures Galvanic isolation between the detector where the current-signals flow, and ground. A remarkable difference compared to other methods used so far for the analog transmission of signals via optical means, is that the input stage of the OCCM, the only one that remains at the detector side, is passive; therefore, it does not require to be powered. This is the most distinctive feature of the OCCM, which opens new opportunities for the realization of multichannel analog links for particle physics experiments and other applications requiring Galvanic isolation and linear transmission with a dynamic range of at least two orders of magnitude. In addition, operation at LAr or LXe temperatures improves the loop-gain by a factor × 2 . The signal bandwidth, at present about 5 MHz , is expected to increase by at least the same factor by optimizing the gain-bandwidth product of the open-loop amplifier.

스마트 홈을 위한 CAN 기반 화재 감지 시스템의 구현

This paper presents a network based fire detection system using CAN, in order to evaluate feasibility of home automation protocol for smart home. In general, because a traditional fire detection system has an analog transmission method with 4-20mA current, it has several shortcomings such as weakness to noise. Hence, as an alternative to the traditional system, this paper presents the architecture of CAN based fire detection system and the design method of CAN communication network. Also, the performance of the suggested system is evaluated through an experimental testbed. Especially, CAN has several advantages such as low cost and easiness of implementation compared to Ethernet or ARCNET, which are low layer of BACNet. Therefore, if CAN is adopted as low layer of BACNet, the home automation system is implemented more effectively.

Brain haemodynamics modelling using electromagnetic systems characteristics

The paper deals with modelling and simulation of a human brain arterial system using analogous electromagnetic systems, especially propagation characteristics of electric transmission lines. Cascade connection of analogous equivalent transmission line elements represents a vessel tree concerning both the electromagnetic parameters and the topology. Elec- tromechanical analogy between physiological and electromagnetic values enables a description and following simulation of a cerebral haemodynamics by means of electric circuits analogous relations. The vascular dynamics modelling and simulation represents an important tool for the non-invasive computer-aided investigation of the brain arteries pathological deformations. The presented simulation results give the information about the blood dynamic characteristics also in the case of cerebral arterial stenoses or aneurysms under various stenosis degrees. The obtained results can provide helpful knowledge for the practical treatment of the basic brain arteries.

Trigger electronics for the Alice PHOS detector

The Photon Spectrometer of ALICE consists of 5 identical modules of 56×64 PWO crystals with a total of 100° azimuthal coverage of the barrel. The electronics required for implementing both the L0 trigger for high luminosity p–p physics and the L1 trigger for high p T Pb+Pb physics has been studied. A full integration of the trigger logic into the detector's enclosure is based on analog transmission of fast trigger sums between stacks of front-end boards and trigger-router units. The latter contain 112 digitizer channels of 10 bit, which are mapped into a single FPGA per trigger unit, covering areas of 24×16 crystals. The running modes allow for Level-0 trigger at 800 ns and Level-1 at 6200 ns trigger latencies. The design and status of the PHOS trigger electronics are outlined.

Sampled-grating DBR laser-based analog optical transmitters

Sampled-grating distributed Bragg grating (SGDBR) laser-based widely tunable optical transmitters are investigated for application in high-performance analog links. More than 45 nm tuning range, 40 dB sidemode suppression ratio, and peak relative intensity noise below -153 dB/Hz is measured. SGDBR lasers integrated with semiconductor optical amplifiers and electroabsorption modulators (EAMs) are characterized with spurious free dynamic range of 125-127 dB/spl middot/Hz/sup 4/5/ over the wavelength tuning range. It is also shown how the modulation response of the EAM is affected by the optical power to limit the performance of the analog transmitter.

Study of the reliability of a binary symmetric channel under non‐Gaussian disturbances

AbstractThe field of digital and data communications is becoming increasingly dominant because digital transmission offers data processing options and flexibilities not available with analog transmission. The main feature of a digital communication system is that during a finite interval of time, it sends a waveform from a finite set of possible waveform. One of the most important and fundamental models of communications channels is the binary symmetric channel (BSC). An important measure of system performance in a digital communication system is the probability of error. In this paper, the probability of error, the reliability, the entropy and the channel capacity of a BSC model are studied under non‐Gaussian noise disturbances. Namely, Cauchy, Laplace and logistic distributions are considered. It is found that the reliability of the signaling system is low under non‐Gaussian noise distributions compared to the Gaussian noise distribution. Several methods were used to reduce the error probability. The amount of improvement in reliability using the reduction methods is higher in the case of Gaussian noise. In order to achieve high reliability under non‐Gaussian noise distribution, it is required to increase signal‐to‐noise ratio (SNR) and increase number of repetitions when sending the same signal different times. Finally, it is observed that increasing the reliability for Cauchy distribution noise has totally failed based on sending the same signal different times and summing the received signals. Copyright © 2003 John Wiley & Sons, Ltd.

Multimedia on TV and the Future for Mobile Usage

Traditional television provided via terrestrial antenna is in a state of disuse, designated as antiquated by many people who are unaware that this reception was the only means of receiving TV for decades, until the advent of cable and satellite. Only 8% of the viewers in Germany have been able to resist the definite added value provided by these alternative forms of reception. — The change in recent years mainly concerns the public broadcasters who are bound by German law to deliver programs to the whole population. As a consequence of the loss of audience share, the cost per viewer of terrestrial program delivery services has increased exorbitantly. However, instead of ending terrestrial transmission, the German government decided to digitize current analog transmissions in order to offer a new system. The new system would afford an opportunity to utilize the benefits of digital transmission and incorporate the experiences of foreign markets into a plan for the successful introduction of digital terrestrial television (DTT). — In spite of diminished euphoria in other countries, Germany has concentrated on the clear advantages of DTT, including its ability to support mobile reception and data services. As a consequence, the introduction of DTT has great potential for successful placement in the market. German Television Zweites Deutsches Fernsehen (ZDF), the largest TV broadcaster in Europe, aware of its special responsibility has been involved in the project from the very beginning.

Hybrid AM-VSB/256-QAM/internet transport systems in the campus

We propose and demonstrate simultaneous transport of 1556 nm downstream CATV analog video, 256-quadrature amplitude modulation (QAM) digital TV and Internet access signals, as well as 1310 nm upstream Internet access signals over the existing multimode fiber (MMF) in the campus. This technique makes possible analog and digital video transmission, gigabit Ethernet as well as Internet access to the classrooms through the existing MMF. Our proposed system has the distinctive advantages of simplicity and lower cost, and is thus eminently suitable for fiber to the classrooms application.

MF AM folded monopole characteristics

Folded monopole antennas have been used for many years in medium frequency amplitude modulation broadcast applications. These antennas offer a grounded radiating structure with a height approximating a quarter wavelength. Folded monopoles have been studied exhaustively during a previous effort in an attempt to characterize the input impedance and directivity characteristics as a function of monopole height. As a result it was observed that several impedance regions can be achieved as a function of antenna height and cage diameter: Some of these regions permit a bandwidth operation sufficiently broad to support a high fidelity response for analog or digital transmissions. This type of antenna can be useful at different heights including a self matching region at the standard 50 ohms impedance. By choosing the appropriate antenna physical dimensions, antenna tuners can be avoided and thus it increases efficiency. Measurements have been made on a full scale 72 meter tower with a 6 wire cage in order to validate the calculated antenna input impedance and directivity. The cage and supporting mast make up the equivalent of a transmission line. For this reason different standard triangular towers were analyzed in order to determine their effect on the input impedance. Tower effective radius is determined taking into account the tower width and the tower leg diameter. At the same time, a minimum antenna height with maximum efficiency has been analyzed to solve the hard problem for installations at places where antenna height is a challenge for the designer.

Combining digital and analog signals for US IBOC FM broadcasting

IBOC DAB (In-Band On-Channel Digital Audio Broadcasting) requires the simultaneous broadcast of an analog and a digital signal within one channel of the FM band. Because broadcasters are adding IBOC to their existing systems, it is vital that they achieve maximum power efficiency while working within their existing space and power limitations. There are currently three different strategies proposed for accomplishing this goal, each having its own advantages and disadvantages. One strategy is to establish a separate, second antenna for the digital service. The other two strategies involve combining the analog and digital signals, either in a single hybrid transmitter or at the output of separate analog and digital transmitters. This paper discusses the equipment required for accomplishing this last strategy.

Wavelength-division-multiplexed analog transmission through plastic optical fiber for use in factory communications

A simple inexpensive analog transmission system is realized using a dual-channel-color LED assembly, a plastic optical fiber, a dual-channel-color sensor assembly, and a crosstalk elimination circuit. The transmission system, covering DC to 10 kHz, has a distortion factor of less than 2% and a crosstalk of less than -40 dB, and is suitable for use in factory communications.

Nonquasistatic transient model of fully-depleted SOI MOSFET and its application to the analysis of charge sharing in an analog switch

A fast one-dimensional (1-D) numerical model suitable for circuit analysis has been developed for fully-depleted silicon-on-insulator MOSFETs. The novel important feature of our CAD-oriented approach consists in a rigorous treatment of the nonquasistatic charge redistribution that ensures accuracy under fast switching conditions. The capabilities of this model are exemplified through the simulation of an analog transmission gate to evaluate the impact of charge sharing effects.

Spatial phase information transmission through an optical fiber by coherence function synthesis

Transmission of one-dimensional spatial phase information by low-coherence light through a single-mode optical fiber is experimentally demonstrated by use of space-time conversion at a 4-f Fourier coherence function shaper and time-space conversion with spectral holography. The dispersion during the fiber propagation can be automatically compensated for with spectral holography. However, space-time coupling caused by the transmitter limits the capacity of information transmittable with one coherence function shaping. A significant advantage in the space-time-space conversion with low-coherence light is that an infinite number of signal channels can be multiplexed with a newly invented delay-time division scheme, which can extend this analog transmission to two-dimensional spatial phase patterns.

The port card for the silicon vertex detector upgrade of the Collider Detector at Fermilab

The collider detector at Fermilab is approaching the completion of the silicon vertex detector upgrade for Run II. The port card is a Beryllia multichip module developed to control, read out, and regulate power for the silicon strip readout chips. It has two radiation hard application-specific integrated circuits, parallel fiber-optic transmitters, and voltage regulators. It resides 14 cm from the accelerator beam inside the tracking volume. The function and location of the port card impose severe constraints on its design. This paper presents the port card and describes the adopted solutions to address the main design issues, as well as the result of many characterization tests.