In this paper, we propose two estimation schemes of orthogonal frequency division multiplexing (OFDM) integer frequency offset (IFO) for digital video broadcasting-terrestrial (DVB-T) systems. In the conventional scheme, the decision variable is based on the limited number of the correlations and ratios of pilots of the received samples, and thus, the decision variable contains only a small por...

BACKGROUND For over 60 yr, researchers and engineers have based investigations and the design of cockpit displays and structures upon the presupposition that during flight the pilot maintains a head alignment coincident with the aircraft's vertical axis (z-axis). Recent simulator studies have verified the existence of a pilot neck reflex which refutes this long-standing assumption. This reflex,...

There is a critical gap in attempting to predict aviation system performance between large-scale engineering-oriented simulations and human-in-the-loop experiments. In order to bridge this gap, we have constructed a model of a human pilot taxiing a commercial jetliner using ACT-R, a computational theory of human cognition and performance. The model was constructed on the basis of a task analysi...

Spatial disorientation (SD) accidents are a major contributor to the Class A mishap rate in the US Air Force. A recent investigation showed that transitions between visual meteorological conditions (VMC), when pilots use real-world visual cues to fly, to instrument meteorological conditions (IMC), when pilots have to use instruments to fly, were a leading cause of SD. In VMC, the true horizon i...

BACKGROUND Little is known regarding the symptoms of fatigue that maritime pilots experience during shift work. Moreover, the strategies these individuals use to cope with the onset of fatigue are also unknown. The current study explored the symptoms of fatigue and coping strategies experienced by maritime pilots when on-shift. MATERIAL AND METHODS Fifty maritime pilots were recruited via an ...

A multiple-input multiple-output (MIMO) indoor radio system is studied to identify the origin of a typical performance degradation. When the data and overlay pilot-sequences for the channel estimation are transmitted at the same time, an error floor at high signal-to-noise ratio is normally observed. The floor is caused by channel estimation errors due to the interfering data signal. The cross-...

The most common lethal accidents in General Aviation are caused by improperly executed landing approaches in which a pilot descends below the minimum safe altitude without proper visual references. To understand how expertise might reduce such erroneous decision-making, we examined relevant neural processes in pilots performing a simulated landing approach inside a functional MRI scanner. Pilot...

Massive multiple-input multiple-output (MIMO) is a promising technology that provides high system capacity, and with excellent performance in energy efficiency and system robustness. However, pilot contamination restricts the system performance due to the limited length of orthogonal training sequences. In this paper, we propose optimization of nonorthogonal pilots for uplink training. The Gras...

This study reports the development and evaluation of time series based objective pilot performance metrics. From a previously developed array of autocorrelation and Fourier analysis based metrics, five Fourierbased metrics that employed a threshold value were chosen to investigate their effectiveness in separating pilots who, based on instructor pilot (IP) evaluations, had either passed or fail...

Pilot-assisted channel estimation has been studied only in common cooperative AF (Amplify-and-Forward) OFDM which has no feedback mechanism. In this paper, for cooperative AF-OFDM system, we propose a feedback technique in which the pilot allocation mechanism is adapted to the cooperative mobile channel. Then we show how uniform pilots may no longer be optimal compared with our pilots. After de...