IEEE Transactions on Vehicular Technology

This paper presents a theoretical and experimental analysis on the application of power-line communication (PLC) on a cruise ship. The authors have developed an accurate model of the power grid of a ship when it is used as a PLC channel. The model is developed based on a theoretical approach and validated by a thorough measurement campaign. The accuracy of the model is addressed by a comparison be... View full abstract»

In this paper, the characteristics of ultrawideband (UWB) channels on outdoor roadway and indoor parking environments are investigated. A set of propagation measurements were conducted on roadways and in underground parking garages, and the resulting propagation data consist of approximately 1200 measured signals. Multipath properties are characterized using tapped-delay-line and Saleh-Valenzuela ... View full abstract»

Tropospheric scintillation on Earth-space paths greatly increases at low elevation angles and/or higher carrier frequencies, may impair low margin systems, and can interfere with the power control algorithms used to mitigate rain fading. The amplitude and spectral characteristics of tropospheric scintillation have been well studied for Earth-geostationary-Earth-orbit (Earth-GEO) links, which have ... View full abstract»

In this paper, a generalized 3-D scattering model is presented for macrocellular land mobile radio cellular systems with a mobile station (MS) located at the center of a 3-D scattering semispheroid and a base station (BS) employing a directional antenna located outside of the semispheroid. The effect of the directional antenna is thoroughly observed on spatial and temporal characteristics of the p... View full abstract»

The estimation of the frictional and clamping forces is one of the key issues in the design and implementation of the electromechanical brake (EMB) system. In this paper, a clamping-force control algorithm is presented along with a consideration of the frictional characteristics and the estimation of the clamping force for a planetary reduction gear-type EMB. The frictional model is developed by i... View full abstract»

A control algorithm is proposed for an independent motor-drive vehicle. A sliding-mode control is designed based on the slip ratio, yaw rate, and lateral acceleration of the vehicle to reduce the motor torque at each wheel. The performance of the control algorithm is evaluated by MATLAB/Simulink-CarSim cosimulation and experiments. A test car with two independent drive motors at the rear wheels is... View full abstract»

In this paper, an innovative power-split device (PSD) is introduced, and its application in a hybrid powertrain system is studied. The new PSD is a mechanism that allows operation in two different power-split modes through locking/unlocking of two clutches. In one mode, the PSD operates similar to a standard planetary gear unit, and in the other mode, it works the same as a compound planetary set.... View full abstract»

Collision warning is one of the most important functions of a vehicle safety system. The emergence and expansion of the applications of positioning techniques and dedicated short-range communication (DSRC) have promoted the collision warning system evolution from a simple ranging-sensor-based system to a cooperative system. Differing from prior work that relied heavily on the e-Map, high-accuracy ... View full abstract»

This paper presents a novel batteryless wireless sensor that can be embedded in the road and used for the measurement of traffic-flow rate. Compared with existing inductive loop-based traffic sensors, the new sensor is expected to provide increased reliability, easy installation, and low cost. The sensor requires no external power source and has zero idle power loss. Energy to power this sensor is... View full abstract»

A novel method for guidance of vision-based autonomous vehicles for indoor security patrolling using scale-invariant feature transformation (SIFT) and vehicle localization techniques is proposed. Along-path objects to be monitored are used as landmarks for vehicle localization. The localization work is accomplished by three steps: SIFT-based object image feature matching, 2-D affine transformation... View full abstract»

With the desire bring more comfort and safety to disabled drivers, new technologies have been deemed appropriate for the development of innovative driving assistance. This paper describes the possibility of integrating these technologies for the development of a positive interacting system with disabled drivers. In this context, we suggest a new solution for a braking device that aims at helping p... View full abstract»

In this paper, we propose a systematic design method for an on-glass antenna, which is suitable for receiving frequency modulation (FM) radio in a commercial recreational vehicle (RV). For the main antenna body, we used a mesh-grid structure that most efficiently uses the given space of the glass for broad-matching bandwidth. To obtain the detail design parameters that exhibit optimum radiating pe... View full abstract»

Next-generation wireless networks for personal communication services should be designed to transfer delay-sensitive bursty-traffic flows over energy-limited buffer-equipped faded connections. In this application scenario, a still-open question concerns the closed-form design of scheduling policies minimizing the average transfer delay under constraints on both average and peak energies. Since, in... View full abstract»

We propose a novel class of protograph low-density parity-check (LDPC) codes having a combinatorial rather than a random structure, which are termed multilevel-structured (MLS) LDPC codes. It is demonstrated that they posses a strikingly simple structure and, thus, benefit from reduced storage requirements, hardware-friendly implementations, and low-complexity encoding. Our simulation results prov... View full abstract»

As third-generation (3G) cellular communication systems evolve to higher data rates, channel equalization becomes an important tool in maintaining receiver performance in dispersive channels. Because these systems employ direct-sequence code-division multiple-access (DS-CDMA), they pose unique challenges in equalizer design. In this paper, linear equalization (LE) and decision feedback equalizatio... View full abstract»

This paper develops a family of irregular convolutional codes for bit-interleaved coded modulation (BICM) systems under iterative detection and decoding. Irregular convolutional codes are constructed through irregular puncturing over multiple mother codes of different memory. Strategies based on fixed- and variable-size trellises are proposed to connect different memory mother codes. The use of ir... View full abstract»

The throughput of conventional wireless multicast systems is limited by the multicast user with the lowest channel quality, which leads to a low throughput, particularly if the number of multicast users is large. In this paper, we show that hybrid-automatic repeat request with Chase combining (HARQ-CC) is a promising technique to overcome this problem and optimize the corresponding transmission ra... View full abstract»

Although the system throughput of a wireless communication system considering multiple users' geographical distribution on a 2-D plane and various traffic characteristics is an important performance metric, its mathematical analysis is very difficult due to the nonindependent identically distributed distribution of the received signal-to-noise ratio (SNR) of each mobile terminal and the complex dy... View full abstract»

Characterizing the distribution of the sum of lognormal random variables (RVs) is still an open issue. This paper proposes simple and new quadrature-based approximations of the characteristic function (CF) and the cumulative distribution function (cdf) of the sum of independent and correlated lognormal RVs. Exploiting the recent Hermite-Gauss quadrature-based approximation, which is provided for t... View full abstract»

The design and analysis of differential space-time coding is considered where the receiver, with a single radio frequency (RF) chain, uses switch and stay combining (SSC). Without channel knowledge at the receiver, a receive-power-based switching algorithm is proposed. By deriving the distribution of the received signal on the selected antenna, upper and lower bounds on the Chernoff bound on the p... View full abstract»

This paper proposes computationally efficient algorithms for the detection of symbols of high-level modulation constellations in multiple-input-multiple-output (MIMO) systems. The proposed approach is based on replacing the maximum-likelihood constraint with a finite set of power equality constraints (PECs), resulting in a set of nonconvex optimization problems, which can efficiently be solved usi... View full abstract»

Two pricing games are derived for distributed rate allocation in two cooperative transmission schemes, in which source nodes are assigned orthogonal channels. In the first game, the source nodes multiplex the data streams of the outgoing links through superposition coding. In the second game, the source nodes perform time-division multiplexing over their outgoing links. At the Nash equilibrium of ... View full abstract»

Aiming at minimizing the transmit power of orthogonal frequency-division multiplexing (OFDM) systems subject to the target data rate, the target bit error rate (BER), the maximum allowable power per subcarrier, and the maximum allowable size of constellations, we present a couple of new discrete bit-loading algorithms, named efficient bit filling (EBF) and efficient bit removal (EBR), which are ba... View full abstract»