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 presents fundamental limits and practical schemes for managing data and feedback of coded flows over multiple, half-duplex communication interfaces (routes). We set forth closed-form bounds on the capacity of resource constrained routes. Our work also provides a systematic approach to exploit these bounds in order to solve the allocation of coded packets with a reliability constraint efficiently,...
In this paper, we design an efficient method of simulating wireless networks that use CSMA/CA-based protocols in the MAC layer. In the method, a stochastic model to estimate the CSMA/CA frame transmission delay is naturally incorporated into the conventional fully event-based model. The stochastic model can simplify the interactions between a frame transmitter and its surrounding nodes, which alleviates...
This paper presents a low power UWB radar transceiver IC, which is used to make a radar system with precise range accuracy. The range accuracy is allowed by a variable delay circuit which can control the delay by 5 ps resolution. The detecting range of the transceiver is from 0.15 m to 8.4 m. The measurement results show that the maximum error is 3.75 mm. The circuit is implemented in a 0.13 µm CMOS...
In this paper, a few schemes are presented to improve the performance of aggressive packet combining scheme (APC). To combat error in computer / data communication networks, ARQ (Automatic Repeat Request) techniques are used. Several modifications to improve performance of ARQ are suggested by recent research and are found in literature. The important modifications are majority packet combining scheme...
In this paper the simulation of Rician and Rayleigh fading model and calculation of channel impulse response for these models are reported. Radio channels in radio systems are usually characterized as multipath fading channels. In environment between transmitter and receiver there exist two main signal propagation components, Line-of-Sight (LOS) and Non-Line-of-Sight (NLOS), which are described through...
We Propose a 2K/4K/8K point FFT (Fast Fourier Transform) for OFDM (Orthogonal Frequency Division Multiplexing) of DVB-H (Digital Video Broadcast Terrestrial) Receiver. The proposed FFT architecture utilizes cascaded radix-4 single path feedback (SDF) structure based on the Radix-2/Radix-4 FFT algorithm.[11] We use block floating point scaling technique in order to increase SQNR. The 2K/8K FFT consists...
An adaptive Recursive algorithm based on a simple two sensor system for accurate estimation of the incident angle of a radar reflecting object or alternatively an active emitter is proposed. The overall objective is to find a low complexity method, which provides high resolution estimates and which is capable of adapting to a time varying scenario. Time delay estimation is followed by calculation...
Covering both theoretical and practical interest in different networks layers, multicast routing remains an important topic. In network layer, there are several multicast routing protocols using different multicast routing trees in the literature. However PIM-SM and CBT protocols remains the most used multicast routing protocols; they propose using a shared tree (ST). This kind of tree provides efficient...
We propose a method to measure available network bandwidth using the Internet Control Message Protocol (ICMP). The recently proposed ImTCP technique uses Transmission Control Protocol (TCP) data packets and the corresponding acknowledgement responses to measure the available bandwidth between sender and receiver. Since ImTCP needs to change the sender's TCP implementation, it needs modifications to...
A simplified radar processing scheme for multiple-input multiple-output (MIMO) radar is presented. The scheme uses a single matched filter to process all K waveforms in the MIMO waveform set however requires that K range gates are computed rather than a single range gate as in single waveform radar. The scheme assumes the MIMO waveform set is comprised of time-staggered waveforms and there are mild...
Noncoherent UWB receivers promise low power consumption and low processing complexity but their peak data rate is limited by the delay spread of the multipath radio channel. A recently proposed multichannel autocorrelation receiver (AcR) can break this rate limit because it can demodulate multicarrier signals. The hardware implementation of this receiver architecture is addressed in this paper. We...
Fully automated agricultural field treatments and Precise Farming are coming in shortly; yet increasing production needs demand a more efficient, planned and harmonized interaction between the machinery clusters involved in the work session. Soon a strong, effective and integrated standardization will be more than needed. This is the path the ISO standardization working group ISO TC-127/SC19/WG5 has...
This paper presents a 25 Gb/s clock and data recovery circuit using a full-rate clock and quadrature data phases. An adaptive slicer is used in the system front-end to equalize the distorted data to minimize duty-cycle distortion due to inter-symbol interference. The proposed structure uses an open-loop phase averaging block in the data path to generate the required quadrature phases for phase detection...
Multi-homing is a new feature of SCTP not existed in UDP or TCP. It allows multiple IP addresses to be attached to a single connection to improve stability of data transfer. It significantly enhances reliability and redundancy of transport layer in several levels - from multiple physical network interface cards to complete different logical end-to-end paths. Recently, SCTP protocol was officially...
In this paper, a minimum nonlinear prediction error (MNPE) based channel equalization and timing recovery technique is proposed for chaotic communications systems. This blind technique utilizes the short-term predictability of a chaotic signal to estimate the equalizer coefficients and the timing delay without any training signals. Both computer simulation and experimental setup are carried out to...
Active and passive detection using CP-OFDM modulated signals traditionally assume that targets do not move significantly during the entire observation period. In this paper, a “time-shift” model that compensates for the motion of targets between pulses during the observation period is introduced. Matched filtering based upon this model can be efficiently performed using a combination of the chirp-z...
In this work, a novel online learning algorithm is presented for the synchronization of Global Positioning System (GPS) signal parameters at the acquisition, or coarse synchronization, stage. The algorithm is based on a Bayesian approach, which has, to date, not been exploited for the acquisition problem. Simulated results are presented to illustrate the algorithm performance, in terms of accuracy...
In this paper we study in-order packet delivery delay of two recently proposed network coded transmission schemes with applications in wireless broadcast. Unlike previous works where asymptotic behaviour of decoding or delivery delay was presented, we provide a general analysis of the three conditions under which in-order packet delivery is possible at a receiver: by 1) catching up with the sender,...
To combat Inter-Carrier Interference (ICI) in mobile OFDM systems, ICI can be reconstructed and removed from the received signal with the aid of channel estimation and decision-feedback. Successful ICI cancellation hinges on accurate channel estimation, which includes both the channel gains and ICI gains, the multiplicative coefficients to the neighbor subcarrier signals representing their power leakage...
Intra-vehicular wireless sensor networks is a promising new research area that can provide part cost, assembly, maintenance savings and fuel efficiency through the elimination of the wires, and enable new sensor technologies to be integrated into vehicles, which would otherwise be impossible using wired means, such as Intelligent Tire. The most suitable technology that can meet high reliability, strict...
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.