esa-sceva/satcom-chunk-collection huggingface dataset:
# Real-Time Indoor Positioning Based on BLE Beacons and Pedestrian Dead Reckoning for Smartphones
## 3 Methodology
### PDR Positioning
#### 3.3.1 Step Detection  
Step detection is a key component in the PDR method. Either failing to detect a few steps or detecting extra steps will lead to a decrease in the positioning accuracy. Peak detection is used in the paper for step detection. Accelerations change continuously and periodically when the user moves. A step is detected when the acceleration is greater than a threshold \(a_{th}\). To further avoid false detection, the next footstep is counted if the time interval between two possible steps is greater than a threshold \(t_{th}\). Specifically, the conditions of peak detection are given by  
\[\begin{cases}|a_{m}-g|\geq a_{th}\\ \Delta t\geq t_{th}\end{cases}, \tag{6}\]  
where \(a_{m}=\sqrt{a_{x}^{2}+a_{y}^{2}+a_{z}^{2}}\) is the local synthetic acceleration, \(a_{x}\), \(a_{y}\) and \(a_{z}\) are the 3-axis accelerations, and \(g\) is the the local gravity component. The parameters \(a_{th}\) and \(t_{th}\) are fine-tuned to achieve better accuracy. Using extensive experiments, \(a_{th}\) is set to 1.9 m/s\({}^{2}\). Since \(t_{th}\) should be related to user velocity, the dynamic threshold is adopted with the detection frequency ranging from 1.65 to 2.85 Hz according to different user velocities.
## 5 Fall Detection Application
### Experimental Results
#### 5.2.4 Falling while Walking Experiment  
For the scenario of a person falling while walking, we measured the test subject's spectral signature using the radar, as shown in Figure 6d. We also tracked the movement of the subject's head, shoulder and right hand using video processing. Figure 13 shows three frames from the video of the person falling while walking; the red markers show the tracking of the head movement, the shoulder tracking is shown with green markers and right-hand tracking is shown with blue markers.  
Figure 14 shows that the video analysis signals have the same shape as the signals in the spectrogram, but with a higher frequency value because of the video camera's relatively low frame rate. The walking part of this motion is similar to the results of person when only walking, as discussed in Section 5.2.4. Therefore, only the fall time of this motion will be discussed in the following. In the falling time interval \(2.608\) s \(<t<3.28\) s, the frequency changed in the range \(0.515\) kHz \(<f_{d}<2.11\) kHz, and the slope was \(m_{p}=2.37\) kHz/s. Afterwards, in the time interval \(3.28\) s \(<t<3.3.647\) s, the Doppler frequency decreased to 0 with a slope of \(m_{n}=5.86\) kHz/s.  
Figure 12: Presentation of the measurement results for a walking man. The spectral signature was measured using the MMW radar, and the colored lines indicate the data obtained through tracking the subject’s head, shoulder and right hand in a recorded video.
# Ultra-Reliable Link Adaptation for Downlink MISO Transmission in 5G Cellular Networks
## 2 System Model
### Robust Link Adaptation  
We assume a family of AMC schemes, consisting of a virtually continuous set of possible rates \(r\) for packet transmissions. When transmitted in a block fading channel with SINR \(\gamma\), a packet error probability (PEP) function \(\mathrm{P}_{\mathrm{e}}(r,\gamma)\) characterizes this family. This function is monotonously growing in \(r\), and monotonously decreasing in \(\gamma\). When blocks are sufficiently short such an AMC scheme may be coupled with a retransmission protocol which is able to operate within the target URC latency, see [22]. Based on the measured \(\gamma_{0}\), and knowledge of channel statistics, we construct a probability density \(f(\gamma_{t}|\gamma_{0})\). When rate \(r\) is used, the expected probability of packet error is \(\tilde{\mathrm{P}}_{\mathrm{e}}(r)=\int\mathrm{P}_{\mathrm{e}}(r,\gamma)f( \gamma|\gamma_{0})d\gamma\). If we could use infinitely long codewords, \(\mathrm{P}_{\mathrm{e}}(r,\gamma)\) would be a step function at a threshold value \(\gamma_{t}(r)\).  
When targeting an outage probability \(\mathrm{P}_{\mathrm{out}}\), maximizing \(r\) with infinitely long codewords would lead to the outage capacity. URC frame lengths are foreseen to be shorter than in LTE.  
We are interested in indoors factory settings, however, where coherence bandwidths of tens of MHz are reported [19]. Accordingly, codewords may be of sizeable length in scenarios of interest. When extending to short packets, outage capacity may be an inaccurate performance metric [23]. Knowing the accurate \(P_{\rm e}(r,\gamma)\) and \(f(\gamma|\gamma_{0})\) would allow finding the maximum \(r\) with the given outage probability. Here, for simplicity, we assume step function \(P_{\rm e}(r,\gamma)\), so that maximizing the rate given \(P_{\rm out}\), can be achieved by first finding a threshold SINR \(\gamma_{t}\) so that \(\int_{0}^{\gamma_{t}}f(\gamma|\gamma_{0})d\gamma=P_{\rm out}\), and then finding the \(r\) which guarantees error free transmission at this \(\gamma_{t}\). Accordingly, one can compute a backoff \(b=\gamma_{0}/\gamma_{t}\) related to the link adaptation based on \(\gamma_{0}\). Then one can guarantee that irrespective of the SINR variability, the transmission can be reliably received with a very high probability. We consider URC outage probability \(P_{\rm out}=10^{-5}\), _i.e._, 99.999% reliability.
## 3 Results
### Geart4 Monte Carlo Calculations
#### 3.4.2 Effect of Cut-Off Energy (CE)  
The sensitivity of the Geant4 S factor calculations on the choice of CE used in the simulations is examined in Figure 10. Specifically, the S factor difference, \(100\frac{(\mathrm{S}_{\mathrm{Geant4}}-\mathrm{S}_{\mathrm{PW}})}{\mathrm{S}_{ \mathrm{PW}}}\), between the analytic calculations of the present work (PW) and the Geant4 (version 10.5) simulations, for three CE values (CE = 100 eV, CE = 250 eV, and CE = 1 keV) and three target spheres (R = 0.1, R = 1, and R = 5 mm), is presented. In these simulations, we have set the SL at the default value.  
Figure 10: Percentage difference of S factor between the analytic calculations of the present work (PW) and the Geant4 simulations for different CE as a function of electron energy, and for spheres of radius R = 0.1 mm (panel **a**), R = 1 mm (panel **b**), and R = 5 mm (panel **c**). In these simulations, we have set SL = default.
# A Satellite Task Planning Algorithm Based on a Symmetric Recurrent Neural Network
## 7 Conclusions  
Earth observation is one of the important applications of intelligent satellites. Satellite on-orbit task planning is an important part of the intelligent satellite automatic operation. This paper describes the problem of autonomous task planning for earth observation of intelligent satellite, and establishes a mixed integer programming model for satellite mission planning. We designed a heuristic search algorithm for a symmetric recurrent neural network, based on the characteristics of the model. The schedulable probability of the task is obtained by constructing a symmetric structured recurrent neural network model. The task with the highest schedulable probability is selected to be inserted into the observation scheme, and the iterative calculation is repeated to obtain the optimal observation scheme. Considering that there is no specific research on intelligent satellite task planning, this paper compares several heuristic algorithms with several traditional observation satellite task planning algorithms. The result of experiments proved that the profit of SRNN-HS algorithm is higher than other algorithms (except s100), and the profit gap is significantly lower than other algorithms. The experimental results illustrated that the performance of SRNN-HS algorithm is better than the rule-based heuristic algorithm and the feature extraction-based machine learning heuristic algorithm. However, this algorithm brings the increase of time consumption, which is also the limitation of this algorithm. This paper presents a task planning algorithm which can be used in the background of intelligent satellite iSAT. In the future, we can consider the application of the algorithm and multi satellite cooperative autonomous task planning, so as to improve the observation range and the efficiency of earth observation.  
Conceptualization, S.L.; methodology, J.Y.; validation, S.L.; investigation, S.L.; writing--original draft preparation, S.L.; writing--review and editing, J.Y.; visualization, S.L.; supervision, J.Y.; project administration, J.Y.  
This research received no external funding.  
The authors are grateful to the reviewers and editors for their valuable feedback on our work, which helped to improve the quality of this paper.  
The authors declare no conflict of interest.
# A Multi-Band LNA Covering 17-38 GHz in 45 nm CMOS SOI
## 1 Introduction  
The vigorous progress of wireless transmission presents a growing demand for high data rates, driving the quest for more spectrum-efficient systems and high-frequency broadband applications, such as 5G communication, broadband satellite communication, and millimeter-wave (MMW) automotive radars [1]. Designs for transceivers, as wireless communication systems' front ends, have emerged endlessly. Transceivers covering broadband, suitable for multiple providers and applications, can significantly reduce the cost of research and manufacturing. Thus, the wideband technique has become popular [2]. Low-noise amplifiers (LNA) play an irreplaceable role in determining the noise characteristics, bandwidth, linearity, and sensitivity of the receiver. Figure 1 shows the functional orientation of an LNA in a multi-band receiver.  
The common source (CS) amplifier is utilized for wideband LNA in designs [3; 4; 5]. However, advanced techniques are often needed to improve the poor input matching for CS-LNA. Source degeneration inductors were used in [3], and a bandwidth enhancement  
Figure 1: LNA in a receiver system.  
technique was adopted in [4] to obtain broadband. In other designs [6; 7; 8; 9; 10; 11; 12], wideband LNA was implemented based on the common gate (CG) amplifier, which can provide preferable wideband input matching. Nevertheless, CG-LNA is disturbed by high power consumption. To work out the situation above, a gm-boosting technique was proposed in [11]. The current-reuse technique was also a candidate in [10]. Beyond that, in [10], the low gain was another drawback that made additional stages necessary. In comparison with CS and CG structures, the cascode LNA possesses advantageous high gain, broadband matching, and high reverse isolation, as seen in various works [1; 2; 13; 14; 15; 16; 17; 18; 19; 20; 21; 22; 23; 24]. In this paper, a wideband LNA is proposed in multi-band mode based on the cascode structure. The differential form is adopted to facilitate system-on-chip integration due to its high resistance to the power supply and common-mode noise.  
The reminder of the manuscript is organized as follows: Section 2 introduces the structure of the LNA and the condition of input/output and interstage matching, Section 3 gives the measurement results of the LNA, and Section 4 concludes the work of this paper.
## 1 Introduction
The economic performance of the optimal design of hybrid PV-FC have been evaluated in [28] for electric load in the city of Brest, and the result clearly illustrated that the proposed system was the best alternative choice to a conventional diesel generator, non-polluting, and a reliable energy system with minimum cost of maintenance. An off-grid design hybrid (PV/FC) was optimized to meet residential electric load in an isolated region, and the effect of ambient temperature and dust accumulation of the PV system and design performance were examined. The optimized design was economically viable with 145$/MWh and environmental protection (no carbon dioxide emission) [29]. However, the hydrogen system (electrolyte, tank, fuel cell) equipped with renewable energy sources still has drawbacks such as cost and efficiency. Reference [30] reported that the product of hydrogen from renewable energy sources has costs two to three times higher than that produced from natural gas. With continuous decline in the cost of solar and wind technology, pure hydrogen becomes more affordable in the future. To decrease the cost, development of the technology of the electrolysis of water into hydrogen was recommended. The significant issue facing fuel cells today is the cost. The fuel cell is not economically mature [31]. Furthermore, the challenge of a hydrogen system;s cost is the concern of [32], and considerable improvements are recommended for it to be highly competitive. For backup power at stationary applications, there is no specific efficiency goal, but the fuel cell efficiency directly expresses into the size and cost of both hydrogen storage and electrolyzer due to the fuel cell efficiency is negotiable with its size and its cost. Therefore, an optimization study is most important to determine the efficiency of fuel cell, resulting in up to 50% in achievable efficiency [33]. In this regard, most studies focused on optimization, sizing, and operations techniques of hybrid energy systems, and accordingly techno-economic performances were assessed. Among different topics in operation techniques, the PV tracking techniques have been considered. The literatures review is classified into two sections: studies regarding hybrid energy system whether microgrid or grid-connected and studies assessed the various PV tracking techniques.
## 4 Synthesis of the Repository of Binaural Audio Recordings  
### Composition of Spatial Audio Scenes  
Prior to explaining the procedure taken for the synthesis of the binaural excerpts, the way that spatial scenes were composed must be described first. Figure 2 illustrates the convention used in this paper. Point \(S\) represents a selected individual audio source, be it a musical instrument or a vocalist, whose position is defined by the two coordinates: azimuth \(\varphi\) and elevation \(\theta\). As it can be seen, azimuth \(\varphi\) is measured counterclockwise with respect to a listener's front-facing direction, whereas elevation is measured relative to a horizontal plane, with positive values for the upper hemisphere.  
In this study, a music ensemble is defined as a group of sources, representing individual music instruments or singers, scattered on a spherical cap (a surface of a sphere cut by a plane). To a first approximation, it was assumed that a music ensemble had a  
Figure 1: Methodology outline.  
Figure 2: Composition of a scene containing a front-positioned music ensemble. Points represent individual audio sources (musical instruments or singers). Blue area illustrates a music ensemble.  
circular boundary (in real-life recordings, the shape of ensembles could be elliptical or even irregular). An example of a front-located ensemble is depicted in Figure 2, with dots representing individual audio sources and a blue area illustrating an ensemble. The center of a cap is positioned at the intersection with the line indicating a front-facing direction. Note that the \"size\" of an ensemble is determined by angle \(\alpha\). Since the shape of an ensemble is circular, its width and height are equal. In this study, six values of an ensemble width were considered, namely \(\pm 15^{\circ}\), \(\pm 30^{\circ}\), \(\pm 45^{\circ}\), \(\pm 60^{\circ}\), \(\pm 75^{\circ}\), and \(\pm 90^{\circ}\). The last case represents an ensemble spanning a hemisphere.  
In this work, four types of scenes were taken into consideration, with the ensembles located at the front, back, above, and below a listener, respectively. The procedure of \"composing\" the spatial scenes was as follows. First, a front-located ensemble was created by randomly generating the intended positions of individual audio sources within the ensemble boundary (with a uniform distribution). An ensemble located above a listener was generated by rotating the front-located ensemble by \(+90^{\circ}\) in elevation. The ensemble located at the back of the listener was created as a mirror-like \"image\" of a front-located ensemble. In other words, there was a reflective symmetry between the front- and back-positioned ensembles. Likewise, an ensemble located below the listener was generated, using symmetric reflection of the above-located ensemble.
## 6 Simulation Experiment and Analysis
### Method Limitations and Future Work  
Although the method proposed in this study has demonstrated promising results, it is important to acknowledge certain limitations, and it is crucial to provide avenues for further exploration in future research. Firstly, due to challenges related to the lack of publicly accessible datasets and hardware limitations in acquiring real low-orbit satellite signals, we were restricted to generating signal datasets only in a simulated environment. While this allowed for controlled experiments, the performance may differ when applied to real-world low-orbit satellite signals, which are influenced by more complex noise characteristics, signal distortions, and environmental factors. Moreover, this study only considered low-orbit satellite OFDM signals in an AWGN environment. In more complex electromagnetic environments, a variety of noise types may arise, including interference from other signals, atmospheric noise, and jamming techniques. The robustness of the model to these more complex noise conditions remains unexplored and represents an ongoing research area. Future work will focus on evaluating and improving the detection and identification of low-orbit satellite broadband multi-type signals under dynamic channels.
# Detecting Deception from Gaze and Speech Using a Multimodal Attention LSTM-Based Framework
## 4 Discussion
These confusion matrices are depicted in, respectively, Figure 6a-c, where the rows correspond to the correct class, the columns to the hypothesized one and the values in them are computed as the average over the test recordings belonging to the first fold. As can be observed, for the gaze modality, deception is less confusable than honesty, i.e., it presents a higher identification rate, whereas there is about 36% of truths that are misclassified as lies. In contrast, for the speech modality, the class presenting the best performance is honesty. In this case, more than 55% of lies are incorrectly assigned to the truth class. This distinctive behaviour supports the hypothesis that both modalities carry complementary information, so their fusion is likely to outperform the single-modal systems, as is ratified by the confusion matrix of the multimodal system represented in Figure 6c, and the results shown in Table 2 and Figure 4.  
Finally, as for the comparison of the proposed system with previous studies over the same database, [PERSON] et al. [12] obtained an accuracy at turn level of 57.11% with RF as classifier for the gaze modality and of 56.22% with KNN for the speech modality using hand-crafted compact features in both cases. In contrast, our attention LSTM-based system achieves identification rates of 64.98% and 61.41% for gaze and speech, respectively. This shows that the modeling of the temporal evolution of the features is essential for the  
Figure 5: Attention-Pooling weights for a recording segment of 3 s for gaze and speech features. (**a**) Gaze modality, from top to bottom: FPOGX, FPOGY, MPD feature sequences, gaze attention weights; (**b**) Speech modality, from top to bottom: waveform, log-mel spectrogram and speech attention weights. This segment belongs to the turn #7 of user #34 that has been labeled as deception. ADD task. In the same way, the multimodal system proposed in [12] consisting of the combination of gaze and audio modalities produced an accuracy of 59.42%, whereas our best system (gaze and speech combined with the AP Fusion strategy) obtains a result of 70.55%, that is significantly better.
# Communication Fault Maintenance Decision of Information System Based on Inverse Symmetry Algorithm
## 2 Definition of Algorithm
### Failure Maintenance Decision
#### Parameter Problem  
The field bus of the information system meets the OSI/RM (Open system Interconnection/Reference Model) network protocol, which is generally applied to the physical layer and data link layer protocols. At the same time, the user protocol layer of the eighth layer is specially formulated. Therefore, all communication protocols in the whole network must be coordinated. Any node of the bus network with different communication rate settings (not necessarily the same) will cause the system to be paralyzed, and there cannot be two nodes with the same address in the network. The address range should meet the relevant technical requirements. In addition, the setting of parameters should fully consider the communication medium, network segment, communication distance, and other factors, and the configuration information should also be consistent with the relevant parameters of the actual equipment.
###### Abstract
Finally, based on the temperature and deformation monitoring system of the Chongqing Nanjimen track bridge, the field-measured temperature and transverse and vertical deformation were collected for analysis, and the influence of temperature on the alignment of long-span steel-hybrid beam track cable-stayed bridge was obtained, which provided technical support for the comfort and safety of driving and a scientific basis for the healthy maintenance of the bridge.
# Textile-Based Flexible Coils for Wireless Inductive Power Transmission
## 5 Experimental Procedure  
### Measurement of Electrical Characteristics of Printed Coils  
After printing and curing, the following five essential electrical characteristics were measured and calculated, then they were compared with the theoretical model and calculations to characterize the performance of a coil for WPT:  
* Equivalent Series Resistance (ESR)
* Inductance
* Self-Resonant Frequency (SRF)
* Parasitic capacitance
* Unloaded \(Q\) factor  
ESR was directly measured using a Wayne Kerr 6500B (Wayne Kerr Electronics, London, UK) impedance analyzer at 200 kHz drive frequency. To find the SRF a Rohde & Schwarz ZVB 4 (Rohde & Schwarz, Munich, Germany) vector network analyzer was used to analyze the impedance phase angle in a range of frequencies from 300 kHz to 3 GHz. Using these instruments, the inductance, parasitic capacitance and SRF are found as follows:  
1. Locate the SRF \(f_{SR}\) where the phase angle of the input impedance is zero, using the vector network analyzer.
2. Read the inductance \(L_{coil}\) from the impedance analyzer at the frequency \(1/10\) of \(f_{SR}\) where the parasitic capacitance has negligible effect.
3. Calculate the parasitic capacitance as \(C_{p}=1/\left(4\pi^{2}{f_{SR}}^{2}{L_{coil}}\right)\).  
Figure 6: Thickness and practical DC resistance of printed conductive layer as designed coil compared with theoretical DC resistance in different number of sub-layers and thickness.  
Read the ESR \(R_{e}\) from the impedance analyzer at the frequency 1/10 of SRF and calculate the unloaded \(Q\) factor \(Q_{u}\) using Equation (6).  
To quantify the performance of the printed coil in a WPT application two other type of coils were also measured. One was a flat spiral air-core coil wound using 1.2 mm diameter copper wire with the same equivalent diameter \(d_{avg}\) and \(\Delta\) as the printed coil. The second one was formed using copper adhesive tape on paper to give the same geometry as the printed coil.  
The resonant tank capacitors for each coil were calculated using Equation (7), based on the measured parameters. The tank capacitors were implemented using polypropylene film capacitors which have lowest dielectric absorption and are suitable for the compensation of inductive coils.