4G to 5G Network Evolution: Advantages and Differences

Starting from the emergence of 1st Generation network (1G), wireless mobile communications have been undergoing an evolution - from 2nd Generation (2G), 3rd Generation (3G), 4th Generation (4G) networks to 5th Generation network (5G) at present. The fifth era is only a continuation of the ongoing evolution as it is still in the research phase and is also the basis for further development of industries and the society in general. The paper presents and compares the fourth and fifth generation of wireless mobile communications, focusing on the differences and progress in terms of data transmission rate, capacity, architecture, technology and applied multiple-technique approaches and services provided.

SPARSE CODE MULTIPLE ACCESS CODEBOOK DESIGN USING SINGULAR VALUE DECOMPOSITION

Currently, sparse code multiple access (SCMA) is a commonly used multiple-access technique, and it is a strong candidate for implementation as part of the fifth generation (5G) of wireless mobile communications. Although several design methods are available for SCMA codebooks, we propose a new method that optimizes point-to-point distances within the same codeword and from codebook-to-codebook for the same carrier based on singular value decomposition (SVD). A neural network-based receiver is proposed for detecting and decoding SVD–SCMA codewords. The simulation results show an improvement in the bit error rate (BER) compared to that for methods such as low-density signatures (LDS), SCMA, and multidimensional SCMA (MD-SCMA).

Discrete Multiwavelet Critical-Sampling Transform-Based OFDM System over Rayleigh Fading Channels

Discrete multiwavelet critical-sampling transform (DMWCST) has been proposed instead of fast Fourier transform (FFT) in the realization of the orthogonal frequency division multiplexing (OFDM) system. The proposed structure further reduces the level of interference and improves the bandwidth efficiency through the elimination of the cyclic prefix due to the good orthogonality and time-frequency localization properties of the multiwavelet transform. The proposed system was simulated using MATLAB to allow various parameters of the system to be varied and tested. The performance of DMWCST-based OFDM (DMWCST-OFDM) was compared with that of the discrete wavelet transform-based OFDM (DWT-OFDM) and the traditional FFT-based OFDM (FFT-OFDM) over flat fading and frequency-selective fading channels. Results obtained indicate that the performance of the proposed DMWCST-OFDM system achieves significant improvement compared to those of DWT-OFDM and FFT-OFDM systems. DMWCST improves the performance of the OFDM system by a factor of 1.5–2.5 dB and 13–15.5 dB compared with the DWT and FFT, respectively. Therefore the proposed system offers higher data rate in wireless mobile communications.

AT90s8535D CHIP APPLICATION FOR HEART RATE VARIABILITY DIAGNOSTIC SYSTEMS

By using wireless mobile communications and mobile information terminals, Internet and the linking of computers and information technology to human bodies effectively, mobile computing can play an important role in modern technology that can be used by anybody anytime, anywhere, and can reconsider new technology with physiological measurements and reconstruct it creatively. In particular, mobile computing can intervene in the process of inducing biometric changes before diseased symptoms develop into diseases in an aging society. Nevertheless, there are difficulties, such as data, treatment by many parameters, ambiguity of data standardization and difficulty of the simultaneous collection of data etc. Therefore, in this study, a system was embodied by excluding time limiting factors using mobile computing and selecting the mobile neural dynamic coding method based on bioelectric signals. As a result of the experiment, it could be a model for biomedical Signal Mobile Analysis Devices and mobile biometric measuring devices, whose self-measurement can be made possible by an academic approach. Furthermore, it became the research foundation of the atypical characteristics of the formation of bioelectrical signals based on mobile applications and could be modeled in the structure circuit form of a biosignal.