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Top1. Introduction
The twenty-first century is the era of evolution of mobile technology. The services and applications demanded by the user from the mobile systems are accelerating with each coming day. Earlier and even today, mobile is the preferred way for voice communication for more than million subscribers in rural and urban areas in India. The introduction of packet switching technique allows a large set of data services from smart-phones, tablets and laptops to go mobile. Presently from the traffic point of view, data volumes in mobile networks have greatly exceeded the voice volumes. Therefore, mobile networks have turned from voice dominated to data dominated. Intensive growth is catered by, Long Term Evolution (LTE) standards that are developed to furnish necessary network capacity. Increasing channel utilization achieves increase in capacity.
Polar codes have been the subject of active research in recent times, mainly due to the fact that they are the provably capacity achieving codes, with explicit construction and very low complexity of encoding and decoding. The polar codes were invented by Erdal Arikan using a novel concept called channel polarization. Soon after, both the concept of channel polarization as well as polar codes has been extended to a number of applications and generalizations. An important characteristic of polar codes is their non-universality. That is, different polar codes are generated depending on the specified value of signal-to-noise ratio (SNR), known as the design-SNR. A change in operating SNR is possible in practice but a change in code according to SNR is not desirable. Therefore, to construct a polar code at one design-SNR and use it for a range of possible SNRs is the biggest challenge. The choice of design-SNR is critical for the performance at all SNRs of interest. Therefore, there is a need to study in identifying the best design-SNR for polar code construction-based communication systems (Vangala & Viterbo, 2015). This work focuses on developing a system using polar-code. The application considered is voice and data for mobile communication. Further, modulation M-ary Phase Shift Keying (MPSK) techniques in the presence of additive white Gaussian noise with Rayleigh fading effect are considered in this work. For performance optimization, Taguchi Methodology is used. This method helps in the selection of appropriate modulation techniques and effective FEC coding scheme for efficient utilization of two communication resources, transmitter power and channel bandwidth. In mobile communication system, both the resources are precious. By predicting network coverage, proper radio link design is useful for network optimization.
In this paper an attempt to double the network capacity by adopting higher modulation scheme and designing efficient encoding and decoding algorithm for polar code based mobile communication system that can utilize available bandwidth efficiently. The propose system saves channel bandwidth and provides services to more and more mobile users by minimizing network congestion. The contents of the paper are organized as follows. Section 2 outlines more insight into the literature survey. Section 3 develops the parameter interaction through fish bone diagram for experimental design. Section 4 presents the test engine model development for simulation and experimentation. Section 5 explains about plan of design of experiment using Taguchi method for system optimization. Section 6 discusses result. Finally, the paper concludes in section 7, based on the inferences of the study.
This work is valuable for the field of mobile communication due to use of polar code for better performance and capacity increase as well as the Euclidian distance technique is used further to co-relate the received bits with transmitted bits. The paper uses correction after decoding process to improve bit error rate, this algorithm is very well suited for polar code-based communication system. The concept used in paper optimizes number of computations, complexity and required SNR to design practical implementable decoder.