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In recent times, the demand for mobile broadband communications has increase exponentially due to the creation of new multimedia applications. To cater for this trend, dense deployment of cellular networks with aggressive frequency reuse patterns has been proposed. In this regard, densification of femtocells is a promising concept to meet growing mobile service requirements and for sustainability of users’ Quality of Service (QoS). However, an ultra-dense network (UDN) faces serious interference problems. One of this is the Inter-Cell Interference (ICI) caused by the simultaneous usage of the same spectrum in different cells. The problem becomes more complex when femtocells are located on cell edge area of macrocell. ICI reduces system throughput and network capacity, and has a negative impact on cell-edge users. Therefore, reducing the effects of interferences is an important issue in UDN. Hence, a critical issue arises: are conventional reduction scheme still effective to tackle the interference in UDN? To shed light on the problem, this paper provides a comprehensive survey of the methods for reducing interference in femtocell UDN. This survey aimed to provide a concise introductory reference for early researchers in the development of interference reduction scheme in femtocell. These methods are classified based on the nature of operation, investigated as to their strength and weaknesses, and then examined via several research studies which make use of each approach. Furthermore, technical challenges in each research study were identified. Finally some remarks for enhancing the research study were provided and potential direction for future research were highlighted.

Water is the basis for human survival and growth, and it holds great importance for ecological and environmental protection. The Hindu Kush Himalaya (HKH) is known as the “Water Tower of Asia”, where water influences changes in the global water cycle and ecosystem. It is thus very important to efficiently measure the status of water in this region and to monitor its changes; with the development of satellite-borne sensors, water surface extraction based on remote sensing images has become an important method through which to do so, and one of the most advanced and accurate methods for water surface extraction involves the use of deep learning networks. We designed a network based on the state-of-the-art Vision Transformer to automatically extract the water surface in the HKH region; however, in this region, terrain shadows are often misclassified as water surfaces during extraction due to their spectral similarity. Therefore, we adjusted the training dataset in different ways to improve the accuracy of water surface extraction and explored whether these methods help to reduce the interference of terrain shadows. Our experimental results show that, based on the designed network, adding terrain shadow samples can significantly enhance the accuracy of water surface extraction in high mountainous areas, such as the HKH region, while adding terrain data does not reduce the interference from terrain shadows. We obtained the water surface extraction results in the HKH region in 2021, with the network and training datasets containing both water surface and terrain shadows. By comparing these results with the data products of Global Surface Water, it was shown that our water surface extraction results are highly accurate and the extracted water surface boundaries are finer, which strongly confirmed the applicability and advantages of the proposed water surface extraction approach in a wide range of complex surface environments.

Abstract The advancement of communication and radar systems has triggered the demand for in‐band full‐duplex (IBFD) operation. IBFD is regarded as one of the most outstanding technologies in terms of its ability to improve spectral efficiency and data rate. IBFD operation has the potential not only to enable communication or radar systems separately, but to help realising radar sensing and communication at the same time, known as Joint Communication and Sensing (JC&S) technology. In realisation of IBFD and JC&S systems, self‐interference (SI) is the key challenge for antenna designers. In this article, a comprehensive survey on SI reduction techniques in the antenna domain is provided and the advantages and disadvantages of each technique are studied. SI reduction techniques have been proposed separately but an elaborated review of relevant techniques with a comparative study has not been presented yet. For the first time, a systematic comparative study of different SI reduction techniques is graphically presented to cover a comparison based on isolation, gain, and impedance bandwidth in terms of before and after SI reduction techniques. Moreover, this study also explores how antenna isolation characteristics vary with respect to the thickness and the permittivity of the substrate without any SI reduction technique.

Abstract Microphone leakage or crosstalk is a common problem in multichannel close-talk audio recordings (e.g., meetings or live music performances), which occurs when a target signal does not only couple into its dedicated microphone, but also in all other microphone channels. For further signal processing such as automatic transcription of a meeting, a multichannel speaker interference reduction is required in order to eliminate the interfering speech signals in the microphone channels. The contribution of this paper is twofold: First, we consider multichannel close-talk recordings of a three-person meeting scenario with various different crosstalk levels. In order to eliminate the crosstalk in the target microphone channel, we extend a multichannel Wiener filter approach, which considers all individual microphone channels. Therefore, we integrate an adaptive filter method, which was originally proposed for acoustic echo cancellation (AEC), in order to obtain a well-performing interferer (noise) component estimation. This results in an improved speech-to-interferer ratio by up to 2.7 dB at constant or even better speech component quality. Second, since an AEC method requires typically clean reference channels, we investigate and report findings why the AEC algorithm is able to successfully estimate the interfering signals and the room impulse responses between the microphones of the interferer and the target speakers even though the reference signals are themselves disturbed by crosstalk in the considered meeting scenario.

Studies have explored the impact of suggestion on the Stroop effect, aiming to understand how effective suggestion is in modulating this phenomenon. The suggestion effect has been replicated in multiple studies, supporting its robustness, but lacks systematic evaluation. We conducted a systematic review and meta-analysis of relevant English-language studies from PubMed, Web of Science, PsycINFO, Scopus, and ScienceDirect since databases inception until January 2023. Quality of included studies was evaluated using the Joanna Briggs Institute (JBI) appraisal checklist, and potential publication biases were assessed. Subgroup analyses were also performed, and effect sizes were estimated using Hedges' g and analyzed using random effects model. The systematic review was comprised of 19 studies. For the meta-analysis, 14 studies examined the suggestion effect on Stroop interference effect (SIE), while six studies investigated suggestion effects on accuracy. Results have revealed significant overall effects of suggestion on Stroop performance in participants, as evidenced by SIE and accuracy. Subgroup analysis based on types of suggestion demonstrated a significant effect on SIE. Six EEG/ERP studies have also been discussed in the context of the review.

Cyclic Prefix – Orthogonal Frequency Division Multiplexing is undoubtedly the fundamental waveform for the upcoming wireless standards. Mixed / multi-numerology scheme is one of the promising key features for 5G wireless standard, but it suffers from a major problem called Inter Numerology Interference (INI). In this study, we have analyzed the Signal to Interference Ratio (SIR) performance for various Sub Carrier Spacing (SCS) and propose a method to minimize the INI, called windowing technique at transmitter. This work also proposes the concept of power domain Non-Orthogonal Multiple Access (pNOMA / NOMA) and the performance analysis of the same is carried out in the mixed numerology environment. Further, windowing technique is employed to minimise INI. The simulation results presented show the efficacy of the novel methodology that has been proposed.

Medium-scale or large-scale receive antenna array with digital beamforming can be employed at receiver to make a significant interference reduction but leads to expensive cost and high complexity of the RF-chain circuit. To deal with this issue, classic analog-and-digital beamforming (ADB) structure was proposed in the literature for greatly reducing the number of RF-chains. Based on the ADB structure, in this paper, we propose a robust hybrid ADB scheme to resist directions of arrival (DOAs) estimation errors. The key idea of our scheme is to employ null space projection (NSP) in the analog beamforming domain and diagonal loading (DL) method in digital beamforming domain. The simulation results show that the proposed scheme performs more robustly, and moreover, it has a significant improvement on the receive signal-to-interference-plus-noise ratio compared to NSP ADB scheme and DL method.