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In this paper, the wideband characterization of the propagation channel in circular metallic indoor environments is addressed, regarding Body Area Networks and 5G small cells, an analytical model for the dependence of the mean delay and the average delay spread on the circle radius, the working frequency and the distance between the transmitter and the receiver being proposed. The derivation of the model is initially done analytically, based on optical physics, after which simulation results allow to obtain the values of the coefficients. The simulator was previously assessed with measurements at 2.45 GHz in a passenger ferry room with a circular shape. For a random positioning of the transmitter and the receiver, and a given distance between them, it is observed that the mean delay and the delay spread increase linearly with the radius; furthermore, the mean delay increases quadratically with the distance, while the delay spread has a concave parabolic behavior, with the maximum being at a distance equal to the radius. In a practical case, regarding the positioning of an Access Point inside the room, it is recommended that it is done at the circle center, in order to reduce delay spread.

In this paper, Body-to-Body communications in indoor and outdoor environments for different on-body antenna configurations and different mobility scenarios were studied, based on system loss measurements at 2.45 GHz. The main objective is to properly characterise the influence of the Transmitter-Receiver configuration on system loss and fast fading behaviour, the latter being modelled by the Rice Distribution. Globally, it is observed that there is no significant difference on the measured average system loss between indoor and outdoor environments, but a strong dependence is seen on the configuration of the antennas and on the mobility scenario. Concerning the Rice Factor, as expected, higher values were obtained in outdoor environments, due to the lower level of multipath, the difference to the indoor case being below 4 dB, depending on the mobility environment and on the positioning of the antennas.

This paper presents the initial results of wideband channel measurements for polarised off-body communications at 5.8 GHz in an indoor environment. Channel Impulse Response measurements were performed simultaneously for two orthogonal polarisations of a wearable antenna (several placements) and repeated for vertical and horizontal orientations of the off-body one. Four types of scenarios were considered in order to investigate the influence of user dynamics, presence of people in the environment, and body-shadowing effects from the user or other persons obstructing Line-of-Sight in between transmitter and receiver. Initial results are presented.

The analysis of cross-polarisation discrimination for Body Area Networks in an untypical environment of cylindrical metallic room has been performed in the paper. This analysis was done based on the measurements carried out for dynamic narrowband off-body channels operating at the frequency of 2.45 GHz. The results have shown that there is a strong dependence of the depolarisation effect on the existence of direct component in the radio channel.

A fast fading analysis for Body Area Networks operating at 2.45 GHz in cylindrical rooms with metallic walls is presented in the paper. A model was developed, based on geometrical ray bouncing. By using an empirically validated simulator, it is shown that it is enough to analyse up to 2nd order reflections. Additionally, it is shown that the normalised radius (to the wavelength) of the cylindrical room does not have a significant influence on fast fading characteristics. The obtained values for the Rice factor, being negative or very close to 0 dB, show that in this kind of environments fast fading can be characterised by the Rayleigh Distribution.

This chapter summarizes IRACON contributions related to the application of IoT in healthcare. It consists of the following three sections. Section 8.1 presents the measurement campaigns and the related statistical analysis to obtain various channel models for wearable and implantable devices. In addition, the importance of physical human-body phantoms used for channel, Specific Absorption Rate (SAR), and Electromagnetic (EM) exposure measurements are examined. Methodologies to improve the accuracy of these phantoms for various frequency bands are also discussed. Section 8.2 outlines methodologies to improve the medium access control (MAC) and networking layers of a body area networks along with possible architectures for remote health monitoring. Several applications such as localization, activity recognition, and crowdsensing and their corresponding technical challenges are also presented in this section. Finally, Section 8.3 introduces the concept of nanocommunications which can be considered as the nano-scale limit of the IoT technology spectrum. It provides an overview of the promising mechanisms that can establish data communication at molecular levels inside the human body as well as various interfacing techniques with macro-scale devices. It also highlights the revolutionary healthcare applications that could be enabled by this technology.

This paper presents an empirical validation of a polarized channel model for off-body communications with dynamic users, based on wideband indoor measurements at 5.8 GHz with a 500 MHz bandwidth. The model is based on geometrical optics, and takes the signal depolarization and influence of user dynamics into account. By considering a scenario with the user walking towards an access point with co-located vertical and horizontal dipole antennas, the simulated receiver (Rx) power is compared against measurements for wearable antenna placements on the chest, wrist and lower leg. The obtained root mean square error is found to be within 2.8 dB for the vertical off-body antenna polarization, and within 3.2 dB for the horizontal one. Fairly matching Rx power values are obtained even when only free space propagation is considered in the simulator, with the error being below 3.4 dB in most cases.

In this paper, an analytical model for slow and fast fading effects in maritime container terminals is derived, from fitting distributions to the results of measurements performed in an actual operational environment. The proposed model is composed of a set of equations, enabling to evaluate fading statistical distribution parameters for different system and environments conditions, as a function of frequency, base station antenna height, and average height of container stacks in a deepwater container terminal. The model's coefficients were obtained from a multivariate linear regression of the fitted distributions parameters, allowing to evaluate the different statistical distribution parameters with a negligible mean error and a standard deviation of the error less than 0.65 dB. It is observed that a good fitting is obtained for slow fading with the Lognormal Distribution, the standard deviation ranging in [1.40, 4.81] dB, while fast fading is well modeled by the Nakagami Distribution with the standard deviation ranging in [0.43, 1.26]. Hence, in a conservative perspective, values of 5 and 1.3 dB are proposed to characterize slow and fast fading, respectively.

In the article the definition of IED has been presented as well as its classification and countering methods. The concept of AEGIS device for neutralization of RCIED has been presented. The usage possibility of AEGIS device in civilian environments has been analysed.

W artykule scharakteryzowano stanowisko badawcze do pomiarow wlasności propagacji fal radiowych w środowiskach zamknietych. Przedstawiono szczegolowy opis zarowno cześci nadawczej, jak i odbiorczej tego stanowiska, a nastepnie przedstawiono opis zamknietych środowisk propagacyjnych, w ktorych przeprowadzono badania pomiarowe. W artykule zaprezentowano opracowane scenariusze pomiarowe, na podstawie ktorych zostala wykonana kampania pomiarowa w rzeczywistych warunkach propagacyjnych. Na koniec zaprezentowano wstepną analize otrzymanych wynikow badan pomiarowych.

This paper presents an off-body channel model for body area networks (BANs) in indoor environments. The proposed model, which is based on both simulations and measurements in a realistic environment, consists of three components: mean path loss, body shadowing, and multipath fading. Seven scenarios in a realistic indoor office environment containing typical scatterers have been measured: five were static (three standing and two sitting) and two dynamic (walk in a fixed place and real walk). The measurement equipment and measurement procedures are described. The mean path loss component is modeled as a log function of distance, the path loss exponent being in the range between 0.4 and 1.6, while a statistical perspective is taken for the other two components, i.e., body shadowing is found to be well modeled by a ognormal distribution and multipath fading by Rice or Nakagami- $ {m}$ distributions, depending on body motion characteristics. The correlation between the selected distributions and empirical data is not lower than 0.95, typically being greater than 0.98. The novelty of this model is that it takes the statistical influence of various parameters and features present in BANs into account, such as body influence, placement of the wearable antennas, user orientation in the environment, dynamism of the BAN scenario, and propagation conditions.

In the paper bioterrorist threats have been presented. Historical background and possible methods of attacks have been described. The most dangerous pathogens and disease entities have been classified. Selected methods of detection and identification of biological weapon have been presented. The wireless system for threats monitoring - developed at Gdansk University of Technology - has been described.

In the article, a novel bitrate adaptation method for data streams allocation in heterogeneous Wireless Body Area Networks (WBANs) is presented. The efficiency of the proposed algorithm was compared with other known algorithms of data stream allocation using computer simulation. A dedicated simulator has been developed using results of measurements in the real environment. The usage of the proposed adaptive data streams allocation method by transmission rate adaptation based on radio channel parameters can increase the efficiency of resources&rsquo, usage in a heterogeneous WBANs, in relation to fixed bitrates transmissions and the use of well-known algorithms. This increase of efficiency has been shown regardless of the mobile node placement on the human body.

In the article an off-body narrowband and ultra-wide band channel model for body area networks in a ferryboat environment is described. Considering the limited number of publications there is a need to develop an off-body channel model, which will facilitate the design of radio links, both from the multimedia services provider and the security point of view, for body area networks in this atypical environment. A mobile heterogeneous measurement stand, using radio distance measurements, which consists of three types of devices: miniaturized mobile nodes, stationary reference nodes, and a data acquisition server, was developed. A detailed analysis of both radio channels&rsquo, parameters was carried out. An analysis of system loss for off-body communication, including mean system loss, large-scale fading (corresponding to body shadowing), and small-scale fading (associated with the multipath phenomenon), both for 868 MHz narrowband and for 6489 MHz ultra-wide band channels, was performed. A statistical analysis of the obtained system loss model parameters was also carried out, good fit to the empirical data is observed.

This paper presents an analysis of the system loss in dynamic off-body communications, based on measurements performed at 2.45 GHz in an office environment. The localization and number of the antennas on a human body influence on the power of received signal. The configuration of two antennas mounted on the different part on human body ensure the higher probability to receive signal with good quality independently to the position of the antennas. The measurement equipment and measurement procedures are described. The mean system loss is in the range of 54.42 dB and 64.28 dB. The difference coefficient between mean values of system loss corresponding to two wearable antennas is in the range of 0.69 dB and 8.76 dB. The standard deviation of the mean system loss is in the range of 6.46 dB and 7.39 dB. Measured correlation coefficient between signal received by two wearable antennas for each scenario is in the range [−1.25.10−3, −1.01· 0−1]. The statistical analysis showed that using space diversity scheme can ensure better quality of the received signal.

In this paper, the system loss in UWB off-body communications in a ferry environment based on measurements is presented. A mobile measurement set-up, consisting of WBAN nodes with UWB DWM1000 modules, was used. System loss was split into LOS and NLOS conditions. For the former, the smallest mean value, 24.4 dB, was obtained for the user approaching the fixed terminal, with the antenna on his chest, and the largest, 28.1 dB, for the user departing from the fixed terminal, still with antenna on the chest, which is directly related to the body shadowing effect. Regarding the latter, all measurement scenarios have a very similar average attenuation, but a 10 dB difference in system loss is visible compared to LOS.

This paper presents a general empirical system loss model for estimating propagation loss in Body Area Networks in off-body communications at 2.45 GHz in a passenger ferry environment. The model is based on measurements, which were carried out in dynamic scenarios in the discotheque passenger ferry environment. The model consists of three components: mean system loss, attenuation resulting from the variable antenna position on the human body, and attenuation due to fading. Preliminary results for system loss components in dynamic scenarios in the discotheque environment are presented. The components of mean system loss and variable antenna position attenuation are modelled by using a linear regression. The obtained root mean square error for the mean system loss is lower than 5 dB. The fading components are modelled by Lognormal and Nakagami-OT distributions.

In this paper a detailed analysis of slow and fast fading effects in container terminal environments is presented, fading distribution parameters are evaluated and an analytical model is proposed. The model is composed of a set of analytical equations allowing to evaluate fading statistical distribution parameters for different system and environments conditions. Globally, it is observed that for slow fading a good fitting is obtained with the Lognormal distribution. Values of μ L and σ L ranges from −1.95 to −1.18 dB and 2.45 to 3.22 dB, respectively. Fast fading effects are well modelled by Rayleigh, Rice or Nakagami distributions with the later one being the more appropriate. The best fit was obtained with the Nakagami distribution with shape and scale parameters, μ N and Ω N , ranging from 0.79 to 1.23 and 2.52 to 3.58, respectively.

In the paper, a characterization of the 868 MHz off-body radio channel in BANs is presented. Measurements were carried out in a ferry environment using a specific set-up. A method for path loss using radio distance measurements (RDMs) was developed. It allows to automate the measurements process and make it independent from the variable speed of a moving person. Based on the observed path loss as a function of distance, the obtained values are divided into Line-of-Sight (LOS) and Non-Line-of-Sight (NLOS) conditions. The results show that, in LOS, the smallest path loss mean value (67.79 dB) and standard deviation (3.87 dB) were obtained for the placement of the mobile node (MN) on the chest (TOF) of a moving person in an approaching scenario (APR). In NLOS, the lowest path loss mean value (71.57 dB) was also obtained for the same scenario. In other scenarios, more than approximately 5 dB higher path loss mean value was obtained.

This paper presents an off-body radio channel measurements in a ferry passenger cabin at 2.45 GHz band, for static sleeping scenarios with different body orientation and on-body antennas placements, and also for upper and lower sleeping berths. The measurements have been performed with two types of on-body wearable receiving antennas: FlexPIFA (flexible planar inverted F antenna), and FlexNotch (flexible adhesive-backed notch antenna) and one patch off-body transmitting antenna. The measurement equipment, measurement environment and investigated scenarios are described. A preliminary analysis of the results — the mean value (μ) and standard deviation (σ) — is presented. In general, the propagation path loss mainly depends on the type and location of the receiving antennas, and also on the body orientation during sleeping and surrounding elements of environment. The lowest mean path loss values (both below 56 dB) were obtained for upper sleeping berth and scenario, where receiving FlexPIFA antennas were mounted on chest and back during lying on the left side. In contrast, the highest values (both over 70 dB) were obtained for upper sleeping berth and scenario, where FlexNotch antennas were mounted on chest and right wrist during lying on the left side. Moreover, the standard deviation varies in a range from 3.7 dB up to 8.0 dB for all cases.

This paper presents an analysis of the polarisation characteristics for the channel in dynamic off-body communications, and an empirical channel model, based on measurements performed at 2.45 GHz in an office environment. Body presence and propagation conditions have a strong influence on signal depolarisation. The model assumes three components for the total path loss: mean path loss, represented by a log-distance function with a path loss exponent of 1.71, Lognormal-distributed shadowing fading, and Nakagami-distributed multipath fading. The Nakagami Distribution shows a trend towards the Rice one in the co-polarised and the Rayleigh one in the cross-polarised channels.

This paper presents an approach to the estimation of mean path loss model parameters in off-body Body Area Networks channels. In this approach, the path loss exponent is constrained to a value obtained from line-of-sight (LoS) propagation in the copolarised channel, considering a generalised static scenario. The proposed approach is compared to alternative ones, by evaluating the coefficient of determination for a set of measurements obtained in an indoor environment. Compared to a traditional approach, a relative improvement of up to 0.7 and typically above 0.4 is observed in the LoS case, while the goodness of fit is unchanged for the non-LoS case.

In this paper, a novel empirical propagation model for mobile radio links in a container terminal environment is presented. Measurement propagation research carried out in the Deepwater Container Terminal (DCT) in Gdansk, Poland is described, and the investigated environment is characterized. The results of the statistical evaluation of the new model are discussed. In addition, statistical tuning of the Walfisch-Ikegami model for the investigated environment is presented.

This paper presents body-to-body radio channel measurements at the 2.45 GHz band, for different body motion scenarios and on-body antenna placements, and both indoor and outdoor environments. Measurement equipment, investigated scenarios and considered environments are described, an initial analysis of results being presented. The mean path loss and the standard deviation depend on the mutual location of transmitting and receiving antennas, type of dynamic scenarios and investigated environments. In general, the lowest mean path loss value (below 57 dB) is obtained for the scenario where two bodies are walking in the same direction along parallel routes and the distance in between bodies equals 1 m; in contrast, the highest value (over 70 dB) is observed for the scenario where both bodies depart from each other being turned back to back. Moreover, the highest standard deviation value (over 13 dB) is obtained for scenarios with antennas mounted on the wrists, which are the most movable parts of the body while walking, and the lowest value (around 2 dB) has been measured for antennas mounted on the head.

This paper presents an off-body fading channel model for Body Area Networks. The proposed model, based on both simulations and measurements at 2.45 GHz in a realistic indoor environment, consists of three components: mean path loss, body shadowing, and multipath fading. The first is modelled as a log function of distance, the path loss exponent being in between 0.4 and 1.6. A statistical perspective is taken for the other two components, i.e., body shadowing is modelled by a Lognormal Distribution, and multipath fading by Rice or Nakagami-m Distributions, depending on body motion characteristics. The correlation between selected distributions and empirical data is always higher than 0.95, typically being greater than 0.98. This model takes the statistical influence of various parameters and features present in BANs into account.

The article presents the assumptions of the AJP-3.15 Doctrine regarding the methods of countering improvised explosive devices. The authors of the article describe and discuss the risks of IED attacks and the ways to eliminate them and minimize the consequences of their use. They briefly present a proposal for a new system for countering IEDs.

The main goal of the paper is to investigate the influence of body orientation and on-body antenna placement on the path loss in off-body communications. In addition, the influence of different bodies is analysed.

In the paper three ways of path loss modelling in the untypical outdoor environments are presented. The exemplary untypical outdoor environment is analyzed. The investigated environment is characterized, and the measurement campaign are shortly described. The following models have been analyzed: the COST231 Walfisch-Ikegami model [1], the modified COST231Walfisch-Ikegami model tuned on the basis of empirical data, and the empirical model destined for maritime container terminal. The comparison of the path loss estimation accuracy using three different models is summarized and analyzed.