Application of Convolutional Neural Network Framework on Generalized Spatial Modulation for Next Generation Wireless Networks

A novel custom auto-encoder Complex Valued Convolutional Neural Network (AE-CVCNN) model is proposed and implemented using MATLAB for multiple-input-multiple output (MIMO) wireless networks. The proposed model is applied on two dierent generalized spatial modulation (GSM) schemes: the single symbol generalized spatial modulation SS - GSM and the multiple symbol generalized spatial modulation (MS-GSM). GSM schemes are used with Massive-MIMO to increase both the spectrum eciency and the energy eciency. On the other hand, GSM schemes are subjected to high computational complexity at the receiver to detect the transmitted information. High computational complexity slows down the throughput and increases the power consumption at the user terminals. Consequently, reducing both the total spectrum eciency and energy eciency. The proposed CNN framework achieves constant complexity reduction of 22.73% for SSGSM schemes compared to the complexity of its traditional maximum likelihood detector (ML). Also, it gives a complexity reduction of 14.7% for the MS-GSM schemes compared to the complexity of its detector. The performance penalty of the two schemes is at most 0.5 dB. Besides to the proposed custom AE CV-CNN model, a dierent ML detector0s formula for SS -GSM schemes is proposed that achieves the same performance as the traditional ML detector with a complexity reduction of at least 40% compared to that of the traditional ML detector. In addition, the proposed AE-CV-CNN model is applied to the proposed ML detector,and it gives a complexity reduction of at least 63.6% with a performance penalty of less than 0.5 dB. An interesting result about applying the proposed custom CNN model on the proposed ML detector is that the complexity is reduced as the spatial constellation size is increased which means that the total spectrum eciency is increased by increasing the spatial constellation size without increasing the computational complexity

Min-Max Hamming Distance Considerations for Activation Pattern Design in Index Modulation

Index modulation (IM) has been widely studied showing promising performance over traditional communication systems. Index pattern plays an important role since its activation methodology determines bit error rate (BER), spectral efficiency (SE) and energy efficiency (EE). This work proposes efficient index activation patterns according to a min-max Hamming distance metric for both orthogonal frequency division multiplexing (OFDM) and non-orthogonal spectrally efficient FDM (SEFDM). Simulations of low-density parity-check (LDPC) coded IM systems in both additive white Gaussian noise (AWGN) and frequency selective channels are provided. Results reveal that the proposed index activation patterns in IM systems lead to improved BER and SE compared to that in traditional OFDM systems. Moreover, peak-to-average power ratio (PAPR) distribution results are presented to demonstrate the EE advantage of the proposed IM systems over OFDM systems

Bit-Interleaved Coded Energy-Based Modulation with Iterative Decoding

This paper develops a low-complexity near-optimal non-coherent receiver for a multi-level energy-based coded modulation system. Inspired by the turbo processing principle, we incorporate the fundamentals of bit-interleaved coded modulation with iterative decoding (BICM-ID) into the proposed receiver design. The resulting system is called bit-interleaved coded energy-based modulation with iterative decoding (BICEM-ID) and its error performance is analytically studied. Specifically, we derive upper bounds on the average pairwise error probability (PEP) of the non-coherent BICEM-ID system in the feedback-free (FF) and error-free feedback (EFF) scenarios. It is revealed that the definition of the nearest neighbors, which is important in the performance analysis in the FF scenario, is very different from that in the coherent BICM-ID counterpart. The analysis also reveals how the mapping from coded bits to energy levels influences the diversity order and coding gain of the BICEM-ID systems. A design criterion for good mappings is then formulated and an algorithm is proposed to find a set of best mappings for BICEM-ID. Finally, simulation results corroborate the main analytical findings

Self-concatenated code design and its application in power-efficient cooperative communications

In this tutorial, we have focused on the design of binary self-concatenated coding schemes with the help of EXtrinsic Information Transfer (EXIT) charts and Union bound analysis. The design methodology of future iteratively decoded self-concatenated aided cooperative communication schemes is presented. In doing so, we will identify the most important milestones in the area of channel coding, concatenated coding schemes and cooperative communication systems till date and suggest future research directions

Differential spatial modulation for high-rate transmission systems

This paper introduces a new differential spatial modulation (DSM) scheme which subsumes both the previously introduced DSM and high-rate spatial modulation (HR-SM) for wireless multiple input multiple output (MIMO) transmission. By combining the codeword design method of the HR-SM scheme with the encoding method of the DSM scheme, we develop a high-rate differential spatial modulation (HR-DSM) scheme equipped with an arbitrary number of transmit antennas that requires channel state information (CSI) neither at the transmitter nor at the receiver. The proposed approach can be applied to any equal energy signal constellations. The bit error rate (BER) performance of the proposed HR-DSM schemes is evaluated by using both theoretical upper bound and computer simulations. It is shown that for the same spectral efficiency and antenna configuration, the proposed HR-DSM outperforms the DSM in terms of bit error rate (BER) performance

Differential spatial modulation for high-rate transmission systems

This paper introduces a new differential spatial modulation (DSM) scheme which subsumes both the previously introduced DSM and high-rate spatial modulation (HR-SM) for wireless multiple input multiple output (MIMO) transmission. By combining the codeword design method of the HR-SM scheme with the encoding method of the DSM scheme, we develop a high-rate differential spatial modulation (HR-DSM) scheme equipped with an arbitrary number of transmit antennas that requires channel state information (CSI) neither at the transmitter nor at the receiver. The proposed approach can be applied to any equal energy signal constellations. The bit error rate (BER) performance of the proposed HR-DSM schemes is evaluated by using both theoretical upper bound and computer simulations. It is shown that for the same spectral efficiency and antenna configuration, the proposed HR-DSM outperforms the DSM in terms of bit error rate (BER) performance

Index modulation for next generation wireless communications.

Doctoral Degree. University of KwaZulu-Natal, Durban.A multicarrier index modulation technique in the form of quadrature spatial modulation (QSM) orthogonal frequency division multiplexing (QSM-OFDM) is proposed, in which transmit antenna indices are employed to transmit additional bits. Monte Carlo simulation results demonstrates a 5 dB gain in signal-to-noise ratio (SNR) over other OFDM schemes. Furthermore, an analysis of the receiver computational complexity is presented. A low-complexity near-ML detector for space-time block coded (STBC) spatial modulation (STBC-SM) with cyclic structure (STBC-CSM), which demonstrate near-ML error performance and yields significant reduction in computational complexity is proposed. In addition, the union-bound theoretical framework to quantify the average bit-error probability (ABEP) of STBC-CSM is formulated and validates the Monte Carlo simulation results. The application of media-based modulation (MBM), to STBC-SM and STBC-CSM employing radio frequency (RF) mirrors, in the form of MBSTBC-SM and MBSTBC-CSM is proposed to improve the error performance. Numerical results of the proposed schemes demonstrate significant improvement in error performance when compared with STBC-CSM and STBC-SM. In addition, the analytical framework of the union-bound on the ABEP of MBSTBC-SM and MBSTBC-CSM for the ML detector is formulated and agrees well with Monte Carlo simulations. Furthermore, a low-complexity near-ML detector for MBSTBC-SM and MBSTBC-CSM is proposed, and achieves a near-ML error performance. Monte Carlo simulation results demonstrate a trade-off between the error performance and the resolution of the detector that is employed. Finally, the application of MBM, an index modulated system to spatial modulation, in the form of spatial MBM (SMBM) is investigated. SMBM employs RF mirrors located around the transmit antenna units to create distinct channel paths to the receiver. This thesis presents an easy to evaluate theoretical bound for the error performance of SMBM, which is validated by Monte Carlo simulation results. Lastly, two low-complexity suboptimal mirror activation pattern (MAP) optimization techniques are proposed, which improve the error performance of SMBM significantly

Proceedings of the Second International Mobile Satellite Conference (IMSC 1990)

Presented here are the proceedings of the Second International Mobile Satellite Conference (IMSC), held June 17-20, 1990 in Ottawa, Canada. Topics covered include future mobile satellite communications concepts, aeronautical applications, modulation and coding, propagation and experimental systems, mobile terminal equipment, network architecture and control, regulatory and policy considerations, vehicle antennas, and speech compression

Double spatial media based modulation.

Masters Degree. University of KwaZulu-Natal, Durban.Multiple-input multiple-out (MIMO) systems have become an increasingly popular technology in wireless communications due to their high data rates and increased reliability. However, several drawbacks degrade the performance of MIMO systems. Inter-channel interference, inter- antenna synchronization, low energy e ciency, and relatively high-complexity receive algorithms are several of the challenges that MIMO systems face. As such, spatial modulation (SM) was introduced as a scheme that is capable of exploiting the advantages of MIMO systems, while simultaneously mitigating its drawbacks. SM provided an excellent method of exploiting spatial diversity, which eventually replaced MIMO systems. However, as the use of SM became more prominent, its drawbacks became more apparent. The spectral e ciency of SM is limited by the logarithmic relationship between spectral efficiency and the number of transmit antennas. Several SM-based transmission schemes, such as quadrature spatial modulation and double spatial modulation (DSM), were introduced with the prospect of improving the spectral efficiency of SM. These schemes have a single radio frequency (RF) chain; therefore, relatively low-complexity receive algorithms are employed. Conventional transmission techniques are referred to as source-based modulation (SBM). Media-based modulation (MBM) is a new attractive transmission scheme that has been recently receiving increased research attention. MBM employs the use of RF mirrors to vastly improve the error performance and/or spectral efficiency of modulation schemes. It has been demonstrated that MBM, coupled with SBM techniques, vastly improves the error performance and can potentially increase the spectral efficiency of these systems. In this dissertation, DSM is extended to employ MBM, such as to improve error performance. The proposed transmission scheme is called double spatial media-based modulation (DSMBM). The theoretical average bit error probability (ABEP) of DSMBM over an independent and identically distributed Rayleigh frequency- at fading channel in the presence of additive white Gaussian noise is formulated. The theoretical ABEP of DSMBM is validated by Monte Carlo simulations, where the error performance matches the theoretical ABEP at high signal-to-noise ratios (SNRs). Lastly, coded channels are investigated. Typically soft-output detection coupled with soft-input channel decoding yields a signicant SNR gain. Motivated by this, this dissertation further proposes a soft-output maximum-likelihood detector for the DSM and DSMBM schemes.List of acronyms on pages xv-xvi