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Abstract: This article deals with several aspects relative to the MIMO propagation channel. Based on simulations and/or measurements, different approaches are used to model the propagation channel. These models are useful for the MIMO system design. Several studies are performed in order to realize realistic simulation of MIMO channel. Different measurement techniques are used in characterizing the propagation channel in various environments. Measurement campaigns made in different situations have been analyzed to obtain the relevant statistical parameters of the channel. Simulation of MIMO channel is then presented. Measurement and simulation results provide an evaluation of the capacity of MIMO channel. Obtained results show feasibility in the integration of MIMO techniques in practical wireless communication systems. [Copyright &y& Elsevier]

Abstract This paper proposes a new scheme for the generation and transmission of a MIMO-OFDM signal over optical fiber using a single local oscillator (LO) at 15 GHz. This technique is based on subcarrier multiplexing and Optical Carrier Suppression (OCS) modulation using both Dual-Parallel Mach–Zehnder Modulator (DP-MZM) and Dual-Drive Mach–Zehnder Modulator (DD-MZM). DP-MZM is used to multiplex the MIMO-OFDM signals while DD-MZM is used to generate the 90 GHz signal by quadrupling. The realistic and global simulation of the complete system is performed to predict the behavior of a Radio over Fiber (RoF) system prior to its realization. The optical and wireless channels are based on Single Mode Fiber (SMF) and Triple-S-and-Valenzuela (TSV) models, respectively. We have exploited the allocated 7 GHz in the 60 GHz band for unlicensed use and we have successfully achieved 50km SMF followed by 3m wireless link at 70Gb/s. In comparison with traditional methods, the technique proposed combines better performance at relatively low-cost. Highlights • New scheme for 2 × 2 MIMO-OFDM RoF using a single local oscillator. • A realistic and global simulation of 2 × 2 MIMO-OFDM RoF system is proposed. • Low-cost technique for Radio over Fiber system [ABSTRACT FROM AUTHOR]

This paper proposes a realistic and global simulation to predict the behavior of a Radio over Fiber (RoF) system before its realization. In this work we consider a 2 × 2 Multiple-Input Multiple-Output (MIMO) Orthogonal Frequency Division Multiplexing (OFDM) RoF system at 60 GHz. This system is based on Spatial Diversity (SD) which increases reliability (decreases probability of error) and Spatial Multiplexing (SMX) which increases data rate, but not necessarily reliability. The 60 GHz MIMO channel model employed in this work based on a lot of measured data and statistical analysis named Triple-S and Valenzuela (TSV) model. To the authors best knowledge; it is the first time that this type of TSV channel model has been employed for 60 GHz MIMO-RoF system. We have evaluated and compared the performance of this system according to the diversity technique, modulation schemes, and channel coding rate for Line-Of-Sight (LOS) desktop environment. The SMX coded is proposed as an intermediate system to improve the Signal to Noise Ratio (SNR) and the data rate. The resulting 2 × 2 MIMO-OFDM SMX system achieves a higher data rate up to 70 Gb/s with 64QAM and Forward Error Correction (FEC) limit of 10 −3 over 25-km fiber transmission followed by 3-m wireless transmission using 7 GHz bandwidth of millimeter wave band. [ABSTRACT FROM AUTHOR]

4×4 Multiple Input Multiple Output (MIMO) optical architecture based on Radio over Fiber (RoF) is proposed for 5G millimeter Wave (mmWave) indoor applications in the unlicensed 60 GHz band. First-order and second-order sidebands, generated by Dual-Drive Mach-Zehnder Modulator (DD-MZM), are exploited as optical subcarriers in order to reduce the number of Local Oscillators (LOs) implemented. Four MIMO-OFDM signals are multiplexed using Dual-Parallel Mach-Zehnder Modulator (DP-MZM) configured to perform Optical Carrier Suppression (OCS) modulation. 60 GHz spacing is ensured between each data signal and its corresponding subcarrier which allows simple heterodyne detection at Radio Access Point (RAP) level. In addition, we have proposed a 4×4 MIMO extension of Triple-S-and-Valenzuela (TSV) radio channel model based on geometrical approach. We demonstrate that the proposed RoF system with adequate configuration can meet the 5G New Radio (NR) requirement in terms of Error Vector Magnitude (EVM). Moreover, Bit Error Rate (BER) performance is evaluated with and without 5G NR channel coding, for transmission over 25 km of optical fiber followed by 3 m of radio channel, by exploiting the overall allocated band at 60 GHz which allows to achieve a very high data rate up to 122.5 Gb/s. • New 4x4 MIMO RoF scheme is proposed to transmit 5G mmWave signals. • MIMO extension of the TSV radio channel model is introduced and used. • Performance evaluation of the proposed RoF system with and without 5G NR channel coding. [ABSTRACT FROM AUTHOR]