A New MIMO Technique Utilizing Superimposed Auxiliary Signals for Simultaneously Achieving Spatial Multiplexing and Diversity Gains in MIMO-Aided Communication Systems (original) (raw)

Hybrid MIMO: A New Transmission Method For Simultaneously Achieving Spatial Multiplexing and Diversity Gains in MIMO Systems

RS Open Journal on Innovative Communication Technologies, 2021

Multiple input multiple output (MIMO) technology has evolved over the past few years into a technology with great potential to drive the direction of future wireless communications. MIMO technology has become a solid reality when massive MIMO systems (MIMO with large number of antennas and transceivers) were commercially deployed in several countries across the world in the recent past. Moreover, MIMO has been integrated into state-of-the-art paradigms such as fifth-generation (5G) networks as one of the main enabling technologies. MIMO possesses many attractive and highly desirable properties such as spatial multiplexing, diversity gains, and adaptive beamforming gains that leads to high data rates, enhanced reliability, and other enhancements. Nevertheless, beyond 5G technologies demand wireless communication systems with, among other properties, immensely higher data rates and better reliability simultaneously at the same time. In this work, a new, novel MIMO technique for simult...

MIMO channels: optimizing throughput and reducing outage by increasing multiplexing gain

TELKOMNIKA Telecommunication Computing Electronics and Control, 2020

The two main aims of deploying multiple input multiple out (MIMO) are to achieve spatial diversity (improves channel reliability) and spatial multiplexing (increase data throughput). Achieving both in a given system is impossible for now, and a trade-off has to be reached as they may be conflicting objectives. The basic concept of multiplexing: divide (multiplex) transmit a data stream several branches and transmit via several (independent) channels. In this paper, we focused mainly on achieving spatial multiplexing by modeling the channel using the diagonal Bell Labs space time scheme (D-BLAST) and the vertical Bell Labs space time architecture (V-BLAST) Matlab simulations results were a lso given to further compare the advantages of spatial multiplexing. Keywords: Diversity MIMO Multiplexing Reliability Spatial Throughput This is an open access article under the CC BY-SA license. 1. INTRODUCTION The need for and data rates and a high quality of service (QoS). Over the years, the ubiquity offered by wireless communication has made it the more preferred means over wired; hence, there has been an increase in research on how to improve the modulation schemes used over the air interface. Multiple input multiple output (MIMO) offers desirable properties that meet most of the requirement stated above. By using multiple output multiple input (MIMO) systems, diversity gain mitigates fading, increases coverage and improves QoS. Multiplexing gain increases capacity and spectral efficiency with no additional power or bandwidth expenditure [1]. The core idea under the MIMO systems is the ability to turn multi-path propagation, which is typically an obstacle in conventional wireless communication, into a benefit for users [2]. With MIMO, the capacity of a communication system increases linearly with the number of antennas, thereby achieving an increase in spectral efficiency, without requiring more resources in terms of bandwidth and power [3-5]. From Figure 1 shows that MIMO technology has two main objectives which it aims to achieve: high spatial multiplexing gain and high spatial diversity. To attain spatial multiplexing, the system is made to carry multiple data stream over one frequency, simultaneously-form multiple independent links (on same channel) between transmitter and receiver to communicate at higher data rates. In low SNR environment, spatial diversity techniques are applied to mitigate fading and the performance gain is typically expressed as diversity gain (in dB) [6]; for higher SNR facilitates the use of spatial multiplexing (SM), i.e., the transmission of parallel data streams, and information theoretic capacity in bits per second per Hertz (bits/s/Hz) is the performance measure of choice [7]. Spatial diversity works on the principle of transmission

Realization of MIMO Channel Model for Spatial Diversity with Capacity and SNR Multiplexing Gains

International Journal of Computer Information Systems and Industrial Management Applications, 2020

Multiple input multiple output (MIMO) system transmission is a popular diversity technique to improve the reliability of a communication system where transmitter, communication channel and receiver are the important elements. Data transmission reliability can be ensured when the bit error rate is very low. Normally, multiple antenna elements are used at both the transmitting and receiving section in MIMO Systems. MIMO system utilizes antenna diversity or spatial diversity coding system in wireless channels because wireless channels severely suffer from multipath fading in which the transmitted signal is reflected along various multiple paths before reaching to the destination or receiving section. Overwhelmingly, diversity coding drives multiple copies through multiple transmitting antennas (if one of the transmitting antenna becomes unsuccessful to receive, other antennas are used in order to decode the data) for improving the reliability of the data reception. In this paper, the MIMO channel model has been illustrated. Moreover, the vector for transmitting signal has been considered by implementing least square minimization as well as linear minimum mean square estimation. Parallel transmission of MIMO system has also been implemented where both the real part and imaginary part of the original, detected and the corresponding received data sequence has been described graphically. One of the important qualities of MIMO is a substantial increase in the capacity of communication channel that immediately translates to comparatively higher signal throughputs. The MIMO communication channels have a limited higher capacity considering the distortions for various deterministic channel recognitions and SNR. The MIMO channel average capacity is achieved more than 80% for dissimilar levels of impairments in transceiver when the value of kappa (Level of impairments in transmitter hardware) reduces from 0.02 to 0.005. The finite-SNR multiplexing gain (Proportion of MIMO system capacity to SISO system capacity) has been observed for deterministic and uncorrelated Rayleigh fading channels correspondingly. The core difference is in the high SNR level. It may occur for two reasons: (a) there is a quicker convergence to the limits under transceiver impairments (b) deterministic channels that are built on digital architectural plans or topographical maps of the propagation environment acquire an asymptotic gain superior than multiplexing gain when the number of transmitting antenna is greater than the number of receiving antenna.

MIMO: State of the Art and the Future in Focus

2016

Antennas of transmitters and receivers have been manipulated to increase the capacity of transmission and reception of signals. Using many elements in antennas to shape beams and direct nulls in a particular point for optimum signal transmission and reception has over decades, had tremendous positive influence in received power and signal to noise ratio (SNR). However, since the antenna elements manipulation can be done both at base station and device terminal, it gives rise to an important method of using several antennas to put and obtain signals to and from space with increased capacity. This principle is termed Multiple-input and Multiple-output (MIMO). This paper discusses application of MIMO in the state of the art and next generation of wireless systems (5G). It also discusses four models of MIMO; SISO, SIMO, MISO and MIMO, considering three method of combing the signals from multipath propagations; Selection combining (SC), Equal gain combing (EGC) and maximum ratio combinin...

MIMO System for Next Generation Wireless Communication

It is well known that Multiple Input-Multiple Output systems enhance the spectral efficiency significantly of wireless communication systems. However, their remarkable hardware and computational burden hinders the wide deployment of such architectures in modern systems. It is a big challenge to reduce hardware complexity, use power with flexible capacity, data rate and bit error rate for the MIMO technology. In this paper we give a theoretical overview of several important theoretical concepts which is related to MIMO. The main part of this thesis can be considered as a most efficient decision for highest capacity with the reasonable BER performance. Hence we came up with an idea to write this thesis paper where we investigated the techniques which we can utilize in order to increase capacity (Bit/s/Hz) and hence provide the less BER in MIMO system. For this system we use Hybrid selection/Maximal-ratio transmission technique over a faded correlated MIMO quasi-static channel. Here faded correlated channel has the ability to carry high capacity data and HS/MRT technique minimizes the BER of system. For this system we use MSK modulation technique which reduces the complexity at transmission side. In practically, For more complexity free in this technique excludes the up converter, amplifier and filtered stage which also alleviate the cost. In this paper at first we try to focus the main important related techniques used in MIMO with the advantages and drawbacks. Then we review the MIMO system from the several past paper works and then we compare the performance of this technique. From this comparison result and using best technique we suggest a future work which will give the best performance. Finally, we describe the technique which we used in our suggested work.

Spatial Multiplexing in Modern Mimo Systems

2016

Digital communication using multiple-input-multiple-output (MIMO) has been regarded as one of the most significant technical breakthrough modern communications. Beside, several different open loop MIMO systems include, Spatial Multiplexing (SM) to provide diversity gain and increase the reliability of wireless links. Under suitable channel fading conditions, having both multiple transmit and multiple receive antennas (i.e., a MIMO channel) provides an additional spatial dimension for communication and yields a degree-of-freedom gain. These additional degrees of freedom can be exploited by spatially multiplexing several data streams onto the MIMO channel, and lead to an increase in the capacity: the capacity of such a MIMO channel with n transmit and receive antennas is proportional to n. Index Terms-Diversity, spatial multiplexing(SM or SMX) , , MIMO, SIC, ML, ZF..

Special Issue: Multiple‐Input Multiple‐Output (MIMO) Communications

2004

The idea of using multiple transmit and receive antennas in wireless communication systems is one of the most important breakthroughs in communication theory during the last decade. Popularly referred to as MIMO technology, this concept can greatly improve data throughput and link performance in wireless networks. In principle, a MIMO system can operate in, or anywhere between, one of the two possible modes.