The advancement in wireless communication applications encourages the use of effective and efficient channel estimation (CE) techniques because of the varying behaviour of the Rayleigh fading channel. In most cases, the emphasis of most proposed CE schemes is to improve the CE performance and complexity for ensuring quality signal reception and improved system throughput. Candidate waveforms whose designs are based on filter bank multi-carrier (FBMC) modulation techniques such as filter bank orthogonal frequency division multiplexing based on offset quadrature amplitude modulation (OFDM-OQAM), universal filtered multicarrier (UFMC) and generalised frequency division multiplexing based on offset quadrature amplitude modulation (GFDM-OQAM) are no exception to the use of these proposed CE techniques in the literature. These schemes are considered as potential waveform candidates for the physical/media access control layer of the emerging fifth generation (5G) networks. Therefore, pinpoint CE techniques represent an important requirement for these waveforms to attain their full potentials. In this regard, this paper reviews the concept of CE as applicable to these waveforms as well as other waveform candidates under consideration in the emerging 5G networks. Since the design of the majority of the waveform candidates is filter based, a review of the general filter design considerations is presented in this paper. Secondly, we review general CE techniques for candidate waveforms of next generation networks and classify some of the studied CE techniques. In particular, we classify the CE schemes used in filter bank OFDM-OQAM and GFDM-OQAM based transceivers and present a performance comparison of some of these CE schemes. Besides, the paper reviews the performances of two linear CE schemes and three adaptive based CE schemes for two FBMC based waveform candidates assuming near perfect reconstruction (NPR) and non-perfect reconstruction (Non-PR) filter designs over slow and fast frequency selective Rayleigh fading channels. The results obtained are documented through computer simulations, where the performances of the studied CE schemes in terms of the normalised mean square error (NMSE) are analysed. Lastly, we summarise the findings of this work and suggest possible research directions in order to improve the potentials of the studied candidate waveforms over Rayleigh fading channels.

Signal blanking is a simple and efficient method to reduce the effect of impulsive noise over power-line channels. The efficiency of this method, however, is found to be not only impacted by the threshold selection but also by the average peak-to-average ratio (PAPR) value of the orthogonal frequency division multiplexing (OFDM) signals. As such, the blanking capability can be further enhanced by reducing the PAPR value. With this in mind, in this paper we evaluate the performance of constant envelope OFDM (CE-OFDM) which has inherently the lowest achievable PAPR of 0 dB; therefore, the proposed system is expected to provide the lower bound performance of the blanking-based method. In order to characterize system performance, we consider the probability of blanking error and signal-to-noise ratio (SNR) at the output of the blanking device. The results reveal that the proposed system can achieve significant improvements over the conventional OFDM blanking-based scheme in terms of minimized probability of blanking error. It will also be shown that output SNR gains of up to 6 dB can be attained over the conventional OFDM blanking-based systems.Index Terms-Blanking, constant envelope OFDM (CE-OFDM), peak-to-average power ratio (PAPR), power-line communications (PLC), signal-to-noise ratio (SNR).

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The integration of power line communication (PLC) and visible light communication (VLC) is increasingly receiving a lot of research interest with the advent of (IEEE 1901, ITUT G.9960/61) and IEEE 802.15.7 standards for PLC and VLC respectively. In particular, there is an underlying gain that could be achieved by leveraging the existing ubiquitous power line network infrastructure to render connectivity, while we also exploit the illumination system of power-saving Light Emitting Diodes (LEDs) for wireless data communication. The ubiquitous nature of these two systems makes us belief that VLC can offer a good complementary wireless data transmission technology to the existing In-House PLC in a similar manner broad-band Ethernet connections enjoys the support of Wi-Fi. This paper thus reports an implementation of a low complexity FSK-OOK In-House PLC and VLC Integration, as well as it's Second-Order Semi-Markov Model. The resulting statistical models facilitates the design and evaluation of forward error correcting codes to mitigate burst error occurrences, as well as optimizing the performance of the overall system.

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