Bidirectional Communication System Research Articles

Bidirectional chaos communication based on semiconductor laser with incoherent optical feedback

In this paper, a bidirectional chaos communication system based on semiconductor lasers with incoherent optical feedback is presented, and the synchronization characteristics and the communication performances of such a system are numerically investigated. The results show that when the parameters of the two lasers are matched, the good-quality chaos synchronization with zero lag time and simultaneously bidirectional message transmission can be realized and when the parameters of the two lasers are mismateched, the synchronization quality and communication performance are affected to a certain extent, but this system possesses good robustness against mismatched parameters and can still realize bidirectional chaos communication within a certain mismatched parameter range.

A 30–50 GHz Wide Modulation Bandwidth Bidirectional BPSK Demodulator/ Modulator With Low LO Power

A 30-50 GHz wide modulation bandwidth bidirectional binary phase shift keying (BPSK) demodulator/modulator using a 2 mum standard GaAs HBT process is presented in this letter. A single balanced mixer with HBT PN-junction diodes is employed in the circuit design. With a local oscillator (LO) power of 0 dBm, this letter demonstrates a maximum conversion loss of 13 dB, a modulation bandwidth of wider than 3 GHz, and a LO-to-RF isolation of better than 45 dB. The BPSK demodulation or modulation can be performed at the same input/output ports of the circuit, and therefore it can be applied to millimeter-wave (MMW) gigabit bidirectional communication systems to further reduce the complexity of the transceivers.

Bidirectional chaos synchronization and communication in semiconductor lasers with optoelectronic feedback

In this paper, a bidirectional chaos communication system based on the optoelectronic feedback semiconductor lasers (SLs) is presented, and the synchronization characteristics and the communication performances of such system are simulated numerically. The results show that the high-quality synchronization with zero lag time and simultaneous bidirectional message transmission can be realized under the suitable system parameters; the internal parameter mismatches of the lasers have influence on the synchronization quality and communication performance, but this system still possesses good robustness to parameter mismatches. Meanwhile, the security can be ensured through a suitable encoding–decoding technique.

A 2 Gb/s Bi-Directional Inter-Chip Data Transceiver With Differential Inductors for High Density Inductive Channel Array

A 2Gb/s bi-directional inter-chip data transceiver is experimentally demonstrated for the first time in 180 nm CMOS technology. Two orthogonal differential inductor pairs are vertically overlapped to make a bi-directional channel. Using these channels, bi-directional communication system is established without any complex circuit techniques. The crosstalk interference problem in channel array is also considered. Differential inductors, due to their noise immunity can make shorter pitches possible in channel array. Compared with the data link with conventional inductor array, this proposed technique achieves 2 times higher channel density with the same speed.

Trans-endocytosis of CD47 and SHPS-1 and its role in regulation of the CD47–SHPS-1 system

CD47 and SHPS-1 are transmembrane proteins that interact with each other through their extracellular regions and constitute a bidirectional cell-cell communication system (the CD47-SHPS-1 system). We have now shown that the trans-interaction of CD47 and SHPS-1 that occurred on contact of CD47-expressing CHO cells and SHPS-1-expressing CHO cells resulted in endocytosis of the ligand-receptor complex into either cell type. Such trans-endocytosis of CD47 by SHPS-1-expressing cells was found to be mediated by clathrin and dynamin. A juxtamembrane region of SHPS-1 was indispensable for efficient trans-endocytosis of CD47, which was also regulated by Rac and Cdc42, probably through reorganization of the actin cytoskeleton. Inhibition of trans-endocytosis of CD47 promoted the aggregation of CD47-expressing cells with the cells expressing SHPS-1. Moreover, CD47 expressed on the surface of cultured mouse hippocampal neurons was shown to undergo trans-endocytosis by neighboring astrocytes expressing endogenous SHPS-1. These results suggest that trans-endocytosis of CD47 is responsible for removal of the CD47-SHPS-1 complex from the cell surface and hence regulates the function of the CD47-SHPS-1 system, at least in neurons and glial cells.

System for reporting high resolution ocean pressures in near real time for the purpose of tsunami monitoring

This invention is the NOAA Deep ocean Assessment and Reporting of Tsunami (DART) system, which utilizes a seafloor tsunameter linked to an ocean surface buoy via bi-directional communication system for near real-time measurement and reporting of tsunamis. The buoy is equipped with a bi-directional satellite and acoustic modem communication system for transmitting data between remote locations, such as tsunami warning centers and the tsunameter on the seafloor.

Improvement of Signal Integrity in Transcutaneous Optical Full Duplex Bidirectional Communication System with Same Near Infrared Wavelength Using Optical Polarizer

Improvement of Signal Integrity in Transcutaneous Optical Full Duplex Bidirectional Communication System with Same Near Infrared Wavelength Using Optical Polarizer

Wireless real time compact radiation detector based on Bi 2O 3/Nb 2O 5 thick film capacitors

A novel cost-effective gamma radiation monitoring system based on metal oxide thick films is presented. The changes in Bi 2O 3/Nb 2O 5 thick film capacitors were monitored in real time under the influence of gamma radiation using miniaturized, low power, bi-directional wireless communication system. The capacitive interface circuitry was based on a Delta-sigma (ΣΔ) modulator using switched capacitor (SC) circuit architecture with integrated on-chip temperature sensor.

Build-on Technology of Bidirectional Optical Communication System Using Bifunctional Organic Diodes

A bidirectional optical communication system using bi-functional organic diodes (BiORDs) has been investigated. The stacked structure used was a front transparent organic light emitting diode (TOLED) and a back organic photodiode (OPD). For a device structure of LiF (1 nm)/semitransparent AlNd (15 nm)/MoO3 (30 nm)/TPD (100 nm)/td-PTC (perylene derivative, 50 nm)/Al, a maximum luminance of 77,400 cd/m2 and a ratio of photo- to dark current of 1,100 were obtained. As a result, an excellent linearity range between the input TOLED current and the output OPD current was obtained at over three orders of magnitude. Cutoff frequencies of the TOLED and OPD were 1.4 MHz and 150 kHz, respectively. For an optical transmission experiment, random burst waveforms of return-to-zero and nonreturn-to-zero were applied to the BiORDs, and an operational frequency of 100 kbps was realized.

Improving neuronal adhesion on chip using a phagocytosis-like event

Efficient integration of neuronal cells and electronic devices could result in hybrid bi-directional communication systems that would enable us to interact at fundamental levels with biological structures and gain insight in the mechanisms governing their functions. Such systems require a very tight coupling between the neuronal cell membrane and the surface of an electronic chip. In this paper we report an approach where the combination of specialized surface chemistry and the manipulation of biological processes, like a phagocytosis-like process, might improve this coupling. As a model, we used coated micro- and nano-sized beads and induced phagocytosis-like events by adding them to cultured cells. The development of the surface chemistry and the results obtained with beads functionalized with a laminin derived peptide are presented.

CMOS Microelectrode Array for Bidirectional Interaction With Neuronal Networks

A CMOS metal-electrode-based micro system for bidirectional communication (stimulation and recording) with neuronal cells in vitro is presented. The chip overcomes the interconnect challenge that limits today's bidirectional microelectrode arrays. The microsystem has been fabricated in an industrial CMOS technology with several post-CMOS processing steps to realize 128 biocompatible electrodes and to ensure chip stability in physiological saline. The system comprises all necessary control circuitry and on-chip A/D and D/A conversion. A modular design has been implemented, where individual stimulation- and signal-conditioning circuitry units are associated with each electrode. Stimulation signals with a resolution of 8 bits can be sent to any subset of electrodes at a rate of 60 kHz, while all electrodes of the chip are continuously sampled at a rate of 20 kHz. The circuitry at each electrode can be individually reset to its operating point in order to suppress artifacts evoked by the stimulation pulses. Biological measurements from cultured neuronal networks originating from dissociated cortical tissue of fertilized chicken eggs with amplitudes of up to 500 muVpp are presented

NEUROBIOLOGY OF THE STRESS RESPONSE: CONTRIBUTION OF THE SYMPATHETIC NERVOUS SYSTEM TO THE NEUROIMMUNE AXIS IN TRAUMATIC INJURY

Acute injury produces an immediate activation of neuroendocrine mechanisms aimed at restoring hemodynamic and metabolic counter-regulatory responses. These counter-regulatory responses are mediated by the systemic and tissue-localized release of neuroendocrine-signaling molecules known to affect immune function. This has led to the recognition of the importance of neuroendocrine-immune modulation during acute injury as well as throughout the recovery period. The period immediately after acute injury is characterized by upregulation of proinflammatory cytokine expression leading to a later period of generalized immunosuppression. The course and progression of the host recovery from traumatic injury and the integrity of its response to a secondary challenge is directly related to the effective control of the immediate proinflammatory responses to the initial insult. Among the neuroendocrine mechanisms involved in restoring homeostasis, the sympathetic nervous system plays a central role in mediating acute counter-regulatory stress responses to injury. In addition to its recognized cardiovascular, hemodynamic, and metabolic effects, the neurotransmitters released by the sympathetic nervous system have been shown to affect immune function through specific adrenergic receptor-mediated pathways. In turn, cells of the immune system and their products have been shown to influence peripheral and central neurotransmission, leading to the conceptualization of a bidirectional neuroimmune communication system. The reflex activation of this bidirectional neuroimmune pathway in response to injury, integrated with the parasympathetic nervous system, and opioid and glucocorticoid pathways responsible for orchestrating the counterregulatory stress response, results in dynamic regulation of host defense mechanisms vital for immune competence and tissue repair. This review provides the biological framework for the integration of our understanding of the neuroendocrine mechanisms involved in mediating the stress response and their role in modulating immune function during and after traumatic injury.

SYNCHRONIZATION OF CHUA CHAOTIC CIRCUITS WITH APPLICATION TO THE BIDIRECTIONAL SECURE COMMUNICATION SYSTEMS

In this paper, a scheme of a bidirectional hyperchaotic communication system is proposed. The hyperchaotic communication system including the transmitter and the receiver is composed of a pair of Chua circuit with coupling characteristics respectively. From the viewpoint of communication security, directly adopting the bidirectional communication system would provide a so-called "theoretical security". This is caused by the coupling relationship between the transmitter and the receiver. With the technique of frequency spectrum, the theoretical security of bidirectional communication systems can be proven. In other words, even if an intruder knows the parameter values of the system, he could not steal information from the system. As a result, it is not necessary for us to use the additional encryption. On the other hand, to achieve the synchronization of bidirectional communications, the method which applies a suitable Lyapunov function and the property of positive definite of a matrix is proposed to design the feedback controllers. Therefore, the message masked by chaotic signal from the transmitter can be perfectly recovered in the receiver. Finally, the simulation results can verify that the proposed method and the scheme of the bidirectional communication are favorable.

The Synaptotagmins: Calcium Sensors for Vesicular Trafficking

The synaptotagmin family of vesicle proteins is believed to mediate calcium-dependent regulation of membrane trafficking. Detailed biochemical and in vivo studies of the most characterized isoform, synaptotagmin 1 (syt 1), have provided compelling evidence that it functions as a calcium sensor for fast neurotransmitter release at synapses. However, the function of the remaining isoforms is unclear, and multiple roles have been hypothesized for several of these. Recent evidence in Drosophila has given insight into the function of some of the remaining synaptotagmin family members. Of the five evolutionarily conserved isoforms in Drosophila, only two, syt 1 and syt 4, localize to most, if not all, synapses. The former is localized to presynaptic terminals, whereas the latter is predominantly postsynaptic. This suggests an intriguing possibility that syt 4 may mediate a postsynaptic vesicle trafficking pathway, providing a molecular basis for an evolutionarily conserved bidirectional vesicular trafficking communication system at synapses.

Performance analysis of low earth orbit satellites for power system communication

In this paper the main performances of communication services based on low earth orbit satellites (LEOs) have been analyzed in order to evaluate their suitability for a typical set of power system monitoring functionalities. As an experimental test bed, an intelligent electronic device (IED) for remote monitoring and protection of power components equipped with a bi-directional communication system based on the LEO satellites of the Globalstar ® consortium has been prototyped. Thanks to the adoption of this facility the main parameters characterizing the performance of the satellite TCP/IP services have been evaluated. They comprise in particular the connection time, the degradation of service and data latency for both packet and asynchronous data services. The experimental results obtained show that the application of LEO satellites based communication technologies exhibits a set of intrinsic advantages that could be particularly useful in several fields of power system communication.

Proposal and implementation of IPv4–IPv6 bidirectional communication system

AbstractCommunication between an IPv6 host and an IPv4 host requires a name server that makes a mapping between an IPv4 address and an IPv6 address, and a translator that performs IP packet conversion. In this paper, we propose an IPv4–IPv6 bidirectional communication system, implement our proposed method, and present the results of performance evaluation. Our system can provide IPv4 hosts with connectivity to more IPv6 hosts in spite of pooling fewer IPv4 addresses. It is realized by adding a source IPv4 address and a port number to an address mapping with cooperation between a name server and a translator. © 2004 Wiley Periodicals, Inc. Electron Comm Jpn Pt 1, 87(12): 49–59, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecja.10203

Implementation of bidirectional chaotic communication systems based on Lorenz circuits

In this paper, we proposed a scheme of the bidirectional secure communication hyperchaotic system, where the chaotic circuits are constituted by two pairs of Lorenz circuits with coupling characteristics between the transmitter and receiver. Because of the coupling relationship between the transmitter and the receiver, even if an intruder knows the coupling values of the system, he could not steal the message from the system from practical simulation results. On the other hand, to achieve the synchronization between transmitter and receiver, two methods are presented to design the feedback control gain. The design idea is to apply a suitable Lyapunov function and the property of positive definite of a matrix to satisfy the direct Lyapunov theorem. Therefore, the transmitting message masked by chaotic state from the transmitter can be guaranteed to perfectly recover in the receiver. To implement the proposed communication scheme, the pairs of Lorenz circuits designed by the operational amplifier, resistor and capacitor elements are also presented in the paper. Finally, the test results containing simulation and the circuit measurement are shown to demonstrate that the proposed method is correct and feasible.

Development of remote control and monitoring system for the FE gun in HVEM.

This paper describes a control and monitoring system for the field emission (FE) gun in the high-voltage electron microscope (HVEM), where the whole FE gun system is located inside a pressure vessel and is floated on a high voltage of 1 MV. The operating condition of the FE gun system is controlled and monitored mainly by a bi-directional communication system between ground and high potential through optical fibres. A mechanical driving system by combination of insulator rods and stepping motors is partially used as a control system for FE gun operation. The monitoring system developed here also functions as a safety circuit that detects abnormal situations, such as an abnormal deterioration of vacuum, and protects the FE tip against fatal damage. The fundamental performance of the microscope has been tested for transmission electron microscope (TEM) and scanning TEM operation modes.

In Vitro Development of Growing Oocytes from Fetal Mouse Oocytes: Stage-Specific Regulation by Stem Cell Factor and Granulosa Cells

The development of follicles in the mammalian ovary involves a bidirectional communication system between the follicular cells and oocyte that is now beginning to be characterized. Little is known about the mechanisms underlying the beginning of the oocyte growth and the acquisition of the competence to resume meiosis by the growing oocyte. In the present study, we devised a multistep culture system for mouse oocytes obtained from 15.5- to 16.5-days postcoitum embryos (mean diameter ± SEM, 9.7 ± 1.3 μm), allowing three stages of the oocyte growth to be identified: (i) an early stage in which the oocyte growth is induced by direct stimulation of a soluble growth factor, namely stem cell factor (SCF), independent of the formation of gap junctions with granulosa cells; (ii) a second phase in which the oocyte growth depends on the combined action of SCF and contacts with granulosa cells; and (iii) a third phase of granulosa cell-dependent, SCF-independent growth. At each stage, key events of oocyte development and differentiation, such as the c-kit reexpression, the early zona pellucida assembly, and the beginning of follicologenesis, were observed to occur independently by the presence of SCF. At the end of the in vitro growing phases, lasting 18–20 days, oocytes reached a size (50 ± 2.5 μm) and a chromatin differentiation (stage I-II) equivalent to those of 9- to 10-day-old preantral oocytes and were unable to complete the growth phase. About 50% of the in vitro-grown oocytes were induced to resume meiosis by okadaic acid (OA) treatment. However, a significant fraction of them (48%) showed inability to maintain the chromosome condensation in M-phase. When in vitro-grown oocytes were treated with UO126, a specific MEK inhibitor that prevents activation of mitogen-activated protein kinases (ERK-1 and ERK-2), for 1 h before, during, and following OA treatment, only 22% of oocytes underwent germinal vesicle breakdown after 24 h from the OA treatment. These studies demonstrate that SCF alone can induce the onset of the oocyte growth. This is, however, not sufficient to fully activate the mechanisms governing the acquisition of the meiotic competence previously described as a 15-day oocyte-autonomous clock starting at the onset of growth. The inability of oocytes to progress into the last stages of growth and the lack of synchrony between nuclear and cytoplasm maturation showed by a subset of them resemble the characteristics of oocytes from connexin-37- and -43-deficient mice and indicate the preantral/antral transition point as a critical stage of oocyte development requiring the coordinated differentiation of the oocyte with granulosa cells and the maintenance of adequate communication between these two cell types to assure the correct oocyte meiotic maturation.

Bidirectional communication system in katydids: the effect on chorus structure

Unlike most acoustic systems evolved for pair formation where only males signal, the katydid Phaneroptera nana has a bidirectional communication system where both males and females sing. Despite extensive study on male chorusing behavior in different communication systems, this behavior has rarely been explored in duetting species. I examined how this bidirectional communication system affects the collective pattern of male signaling. P. nana males alternate their songs, and in response to synthetic stimuli delay their calls, according to the phase of stimulation. Pairs of synthetic calls (simulating alternating males) presented to females elicited equal female response, as long as the intercall interval was 200 ms. Thus, male alternation is imposed by the female’s responsiveness and may be interpreted as a ‘‘jamming avoidance reaction.’’ Further evidence suggests that chorus structure is not merely constrained by the female sensory temporal resolution, but rather is adaptively related to female choice in this species.