The classical Clarke model of mobile radio reception assumes a constant mobile velocity. We, in this paper, relax the assumption of constant mobile velocity to allow the mobile to have constant acceleration and derive expression for the non-stationary autocorrelation function of the channel process in general 2-dimensional (2D) scattering environments. Under suitable assumptions, an expression for Wigner-Ville spectrum is obtained in isotropic scattering environment which suggests that the Wigner-Ville spectrum is a natural generalization of the Clarke's model to constant mobile acceleration scenario.
Mobile agents have the ability to relocate computation and then carry communication with their peers locally. The design and implementation of mechanism to relocate computations requires a careful assessment of security issues. If these issues are not addressed properly, mobile agent technology cannot be used to implement real-world applications. To address such issues this paper proposes two code obfuscation techniques (Memon at el., 2006) for Java-based mobile agents that are compiled into a platform independent byte code format. These techniques involve applying obfuscating transformations to the mobile agent's byte code in order to protect them against malicious attacks. Consequently these techniques prevent automatic software analysis tools, De-compilers, from generating correct source code by introducing syntax and semantic errors in the generated source code. The proposed techniques are applied on sample mobile agent's class files to examine the effectiveness of the techniques in impeding reverse engineering. After obtaining the results, we will reveal the erroneous codes generated by the tested de-compilers
