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Showing 3 results for Moharam

A. Moharampour, J. Poshtan, A. Khaki-Sedigh,
Volume 4, Issue 3 (July 2008)
Abstract

In this paper, after defining pure proportional navigation guidance in the 3-

dimensional state from a new point of view, range estimation for passive homing missiles is

explained. Modeling has been performed by using line of sight coordinates with a particular

definition. To obtain convergent estimates of those state variables involved particularly in

range channel and unavailable from IR trackers, nonlinear filters such as sequential U-D

extended Kalman filter and Unscented Kalman filter in modified spherical coordinate

combined with a modified proportional navigation guidance law are proposed. Simulation

results indicate that the proposed tracking filters in conjunction with the dual guidance law

are able to provide the convergence of the range estimate for both maneuvering and nonmaneuvering

targets.


A. Moharampour, J. Poshtan, A. Khaki Sedigh ,
Volume 6, Issue 1 (March 2010)
Abstract

When a detector sensitive to the target plume IR seeker is used for tracking airborne targets, the seeker tends to follow the target hot point which is a point farther away from the target exhaust and its fuselage. In order to increase the missile effectiveness, it is necessary to modify the guidance law by adding a lead bias command. The resulting guidance is known as target adaptive guidance (TAG). First, the pure proportional navigation guidance (PPNG) in 3-dimensional state is explained in a new point of view. The main idea is based on the distinction between angular rate vector and rotation vector conceptions. The current innovation is based on selection of line of sight (LOS) coordinates. A comparison between two available choices for LOS coordinates system is proposed. An improvement is made by adding two additional terms. First term includes a cross range compensator which is used to provide and enhance path observability, and obtain convergent estimates of state variables. The second term is new concept lead bias term, which has been calculated by assuming an equivalent acceleration along the target longitudinal axis. Simulation results indicate that the lead bias term properly provides terminal conditions for accurate target interception.
Mohamed Hussien Moharam, Aya W. Wafik,
Volume 20, Issue 0 (In Press 2024)
Abstract

High peak-to-average power ratio (PAPR) has been a major drawback of Filter bank Multicarrier (FBMC) in the 5G system. This research aims to calculate the PAPR reduction associated with the FBMC system. This research uses four techniques to reduce PAPR. They are classical tone reservation (TR). It combines tone reservation with sliding window (SW-TR). It also combines them with active constellation extension (TRACE) and with deep learning (TR-Net). TR-net decreases the greatest PAPR reduction by around 8.6 dB compared to the original value.

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