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Mediumband wireless communication refers to wireless communication through a class of channels known as mediumband that exists on the TmTs-plane. This paper, through statistical analysis and computer simulations, studies the performance limits of this class of channels in terms of uncoded bit error rate (BER) and diversity order. We show that, owing mainly to the effect of the deep fading avoidance, which is unique to the channels in the mediumband region, mediumband wireless systems, if designed judiciously, have the potential to achieve significantly superior error rate and higher order diversity even in non-line-of-sight (NLoS) propagation environments where the achievable diversity order is otherwise low., Comment: 6 pages, 5 figures, Accepted for Publication in the Proceedings of IEEE VCC 2023, 28-30 Nov. 2023

The fundamental phenomenon widely known as multipath is unavoidable in wireless communication, and affects almost every element of modern wireless communication systems. The impact of multipath on the received signal depends on whether the delay spread (i.e., spread of time delays associated with different multipath components) is large or small relative to the signalling period of the wireless communication system. In narrowband systems, the delay spread is about one tenth (or less) of the signalling period. The delay spread and the signalling period of broadband systems are in the same order of magnitude. In between these two extremes, there appears to exist an important, yet overlooked, class of systems whose delay spread is neither small nor large enough for them to fall into these two basic classes. In this paper, the effect of multipath on this class of systems denoted henceforth as mediumband is studied, and its channel is characterized in compact form in order to enable future research into this class of wireless communication systems., Comment: 5 pages, 3 figures, Proceedings of IEEE Vehicular Technology conference (VTC-Fall) 2022, London-Beijing

LiFi (light-fidelity) is recognised as a promising technology for the next generation wireless access network. However, little research effort has been spent on the uplink transmission system in LiFi networks. In this paper, an analytical framework for the performance analysis of an wireless infrared-based LiFi uplink at system level is presented. This work focuses on the performance of a single user who is randomly located in a network. Many important factors in practice are taken into account, such as front-end characteristics, channel path loss, link blockage and user device random orientations. In particular, accurate analytical expressions for the statistics of optical channel path loss has been derived. Based on this path loss statistics, the distribution of signal-to-noise ratio (SNR) and the average achievable data rate are evaluated. A channel factor is defined as a quantity which only depends on the used devices, optical channel and noise power spectral density function (PSD). The result shows that with commercial front-end elements, an average data rate of up to 250 Mbps is achievable., Comment: 32 pages

The co-channel interference (CCI) is one of the major impairments in wireless communication. CCI typically reduces the reliability of wireless communication links, but the difficult CCI which is no more or less strong to the desired signals destroys wireless links despite having myriad of CCI mitigation methods. It is shown in this paper that M-QAM (Quadrature Amplitude Modulation) or similar modulation schemes which modulate information both in in-phase and quadrature-phase are particularly vulnerable to difficult CCI. Despite well-known shortcomings, it is shown in this paper that M-PAM or similar schemes that use a single dimension for modulation provides an important mean for difficult CCI mitigation., Comment: 4 pages, 2 figs and accepted in IEEE ICASSP 2019, Brighton, UK

Doppler effect is a fundamental phenomenon that appears in wave propagation, where a moving observer experiences dilation or contraction of wavelength of a wave. It also appears in radio frequency (RF) wireless communication when there exists a relative movement between the transmitter and the receiver, and is widely considered as a major impairment for reliable wireless communication. The current paper proposes Doppler Assisted Wireless Communication that exploits Doppler effect for co-channel interference mitigation. The proposed system also exploits the propagation environment and the network topology, and consists of an access point with a rotating thin drum antenna. The rotating drum receive antenna is designed in such a way that it shifts the interference signals away from the desired signal band. This paper includes a detailed system model, and the results show that under favourable fading conditions, co-channel interference can be significantly reduced. Therefore, it is anticipated that more sophisticated wireless systems and networks can be designed by extending the basic system proposed herein., Comment: 10 pages, 13 figures