Earticle

This paper presents two modifications of the gpICA (geometric post non-linear independent component analysis) algorithm. gpICA algorithm is a novel method to solve the PNL (Post non-linear) scheme. We propose these modifications to improve the mean squared error, the correlation of the recovered signals and algorithm reliability . The first improvement, called compensation, takes advantage of the implicit information given by the point to be linearized. On the other hand, while the original gpICA algorithm uses two sets of two points to make an update, our second modification uses two sets of four points. We present experimental results which validates the effectiveness of each modification. The PNL applications can be seen in sensor array processing, digital satellite, microwave communications, biological systems and nonlinear blind source separation tasks. gpICA can recover the original sources of a nonlinear mixture, unlike some of the other nonlinear BSS algorithms, it does not require any assumption on the distribution of the input signals.

In this paper, we study the performance benefits of turbo coded HSDPA system. This paper provide an overview of high speed data packet access (HSDPA) and focus on the business values that such a highly-efficient access technology would bring to wireless operators, including higher capacity and newer services. In this paper each frame is encoded using a turbo code and channel coding is done by turbo codes is the best method for transmitting information with fewer errors and lower signal power. Turbo coding includes two main modules in it, one being turbo encoder made up of recursive systematic code encoders and second turbo decoder where Log Map algorithm is implemented. HSDPA increases the downlink data rate within a cell to a theoretical maximum of 14Mbps, with 2Mbps on the uplink. The changes that HSDPA enables include better quality and more reliable, more robust data services. In other words, while realistic data rates may only be a few Mbps, the actual quality and number of users achieved will improve significantly.

Chaotic systems are extremely sensitive to control parameters and initial conditions. This feature is effective in the field of cryptography. In this paper we propose image encryption scheme which is based on the chaotic maps of Peter de Jong’s attractor. The image is transferred into the wavelet domain and then appropriate modifications of the wavelet coefficients are done. The main purpose of application of the wavelet transformation is to reduce computation time needed for the encryption process and to reach higher or similar security of the encrypted image.

Route Optimization (RO) is an emerging technique in the area of Mobile Networks (MN). Finding a best solution for the route optimization is still in research. The NEMO (NEtwork MObility) protocol provides network mobility and MIPv6 provides host mobility. A MN can have nodes with NEMO or MIPv6. The NEMO has more complexity in providing RO than MIPv6 in terms of throughput, payload, etc. Sometimes each and every node in the mobile network may not support RO. The nodes that do not support RO must be identified early in order to avoid excessive delay in setting up RO. In this paper, we have proposed a mechanism to reduce the delay in establishing RO by effectively maintaining a table that stores information about whether a node supports RO or not. In order to reduce the table size and search delay, information about RO support is stored in binary value. The outcome of this paper reduces time taken for fall back procedure that in turn reduces excessive delay in establishing RO. In general, it helps to offer better Quality of Services to the customers.