The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
This paper examines the problem of generating testing actions for electronic industry test systems designed for verification of electronic packages of UHF band. This paper shows complex problems of setting amplitude and time parameters of multichannel generators of test signals. The problems of multichannel wide range signal generation and frequency control, rise and fall time control, pulse time...
The Trustful Space-Time Protocol (TSTP) allows for time synchronization to be performed upon receiving any message from another node in a sensor network, removing the need for explicit synchronization messages. Previous work has shown that TSTP performs well under controlled experimental environments. In this work, we analyze how the quality of synchronization in TSTP is affected when nodes are communicating...
This paper propose an asynchronous impulsive control scheme for consensus of second-order multi-agent systems. The proposed control scheme do not require time synchronization among agents. Each agents has its won clock to determine the impulsive instants. By using discretization approaches and the stochastic matrix theory, it is find that the stability of the proposed control scheme depends on the...
Requirements of different applications and usage scenarios on a wireless positioning system is very different. A single positioning system is unlikely to meet all the requirements. UWB based positioning systems offer a solution which would meet all the indoor usage requirements. Though, the theoretical positioning accuracy offered by such systems is very good, in actual implementation, their accuracy...
In beyond silicon research, Quantum-dot Cellular Automata (QCA) emerged as a candidate for replacing the traditional CMOS logic circuits. QCA is a paradigm based on the exchange of information between cells that takes advantage of Coulomb's law. In this work, we managed to extract dependence relations through a circuit designed on QCA Designer simulator. We built small models representing fragments...
This paper discusses the time synchronization issue in wireless sensor networks. An event-triggered average consensus time synchronization algorithm is proposed. This algorithm uses the average time message from one node's one-hop neighbors to update the clock parameters of the node. And it achieved acceptable synchronization accuracy. We also proposed an event-trigger mechanism to reduce the communication...
Underwater wireless sensor networks (UWSNs) provide a promising approach for ocean monitoring. Locating the sensor nodes (SNs) in UWSNs is critical for annotating data samples. However, the global positioning system (GPS) is not available underwater. The locations of SNs are usually interpreted from anchor nodes which are deployed at known locations on the seafloor or sea surface. Due to the characteristics...
Time synchronization over a distributed BLE wireless network poses several challenging problems which may affect the accuracy of time stamping of events recorded by BLE devices. In this paper, we study the accuracy of a time synchronization scheme based on generation of an event in the application program at the time of BLE connection establishment. We discuss the background of the problem, explain...
In industrial applications synchronized sensor nodes are vital for many tasks like multi parameter sampling of complex machinery behavior. The wirelessly connected nodes are usually synchronized to a base station. Therefore, frequency or period estimation of the reference clock is a key issue for all connected tasks like sampling, localization or applying energy optimized communication protocols....
This paper presents the considerations on NCR (Network Clock Reference) variations which impact on the stability of the satellite interactive system operation. We identified what kinds of factors can influence system performance in timing synchronization aspects. The amount of impacts that each factors can cause to the system operations from the realistic calculations and corresponding solutions are...
Although a number of asynchronous physical-layer network coding (PNC) schemes have been proposed, synchronous PNC may still be preferred for its simplicity. In this paper we propose a new symbol-level synchronization scheme which reduces the misalignment to less than one hardware clock cycle period. In addition, we prototype the proposed scheme on the Universal Software Radio Peripheral (USRP) platform...
Localization of wireless networks has remained an active research topic for more than a decade, as it finds more and more applications in numerous scenarios, including environment surveillance, asset tracking, and healthcare monitoring, etc. In this paper, we consider the maximum likelihood localization of a network where some of the nodes are GPS-capable while the others attempt to achieve self localization...
A design and implementation method of radar time domain waveform based on FPGA is presented in this paper, in order to achieve the waveform library building, waveform selection or agility in the transmitter of cognitive radar system. First, the resident phase method and the waveform parameter design method are used to feedback the emission waveform parameters. Then, the DDS (Direct Digital Synthesizer)...
A time synchronization algorithm for hidden mobile node (HMB), which can only receive signals, joining an existing synchronized underwater Acoustic (UWA) sensor network (UASN) is proposed. In order to obtain the location of the HMB or communicate with it, the local time of the HMB should synchronize with the UASN. However, the propagation delay in UWA channels could not be ignored compared to electromagnetic...
The clock synchronization technologies applied to controlling layer and primary equipment like intelligent switchgear of processing layer in intelligent substation are analyzed in this paper. IEEE1588 message timing mode, which can be accurate to nanosecond, is used as the mode of substation system, in order to fulfill the real-time and accuracy requirements of intelligent switchgears and remote control...
In converters possessing multiple distributed controllers the synchronization of and the communication between the various controllers are important topics requiring careful consideration. The controllers should be able to transmit data and commands to each other so that different control modes can be selected, reference values updated, parameters shared and so forth. Synchronization is important...
Emerging protocols for low-power wireless networks increasingly exploit constructive interference and the capture effect. The basic idea is that the synchronous transmission of identical packets by neighboring nodes leads to constructive interference - or at least do not cause destructive interference. This requires that the temporal displacement of packets at receiving nodes is lower than 0.5 μs...
After analyzing the shortcomings of existing synchronization methods based on GPS and the research status of synchronization for Crosswell Electromagnetic Imaging Logging Tool(CEMIT), a feasible synchronization method combined the actual conditions of CEMIT with the basis of existing research is proposed. First of all, GPS receiver provides a high accurate 1PPS, which received by Surface System, and...
In this paper, we simulate the tri-message time synchronization protocol within the cluster sub net for the MAC layer of underwater acoustic network. Distinguished with the traditional TDMA protocols, all sub nodes are time consistent with the cluster node and the sub nodes can be quickly netted in the improved TDMA protocol. We established a network simulation with a bunch of 6 nodes in OPNET software...
A novel run-pause-resume (RPR) debug methodology that can achieve complete cycle-level granularity of debug resolution for multiple clock domain systems is proposed. With this methodology one can pause the normal operation of a system at any cycle of any clock domain and resume the system without causing any data invalidation problem. Bidirectional transactions among different clock domains are analyzed...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.