Digital processing of satellite imagery application to jungle areas of Peru

The author has identified the following significant results. The use of clustering methods permits the development of relatively fast classification algorithms that could be implemented in an inexpensive computer system with limited amount of memory. Analysis of CCTs using these techniques can provide a great deal of detail permitting the use of the maximum resolution of LANDSAT imagery. Potential cases were detected in which the use of other techniques for classification using a Gaussian approximation for the distribution functions can be used with advantage. For jungle areas, channels 5 and 7 can provide enough information to delineate drainage patterns, swamp and wet areas, and make a reasonable broad classification of forest types

Simulation and measurement data-based study on fat as propagation medium in WBAN abdominal implant communication systems

Abstract This paper presents comprehensive study on fat as propagation medium in abdominal implant communication system at low ultrawideband (UWB) frequency range 3.75—4.25 GHz. The main aim is to investigate how signal propagates through visceral and subcutaneous fat layers and how that information can be exploited in implant communication systems. The study is conducted using different methods: electromagnetic simulations, power flow analysis, propagation path calculations and radio channel measurements with animal meat pieces. Simulations are conducted using layer models and anatomical voxel models having different sizes. Results of channel simulations are verified with propagation path calculations. Power flow analysis on cross-cuts of the voxel models is conducted to investigate how the signal propagates inside the tissues. Furthermore, measurements using different animal meat pieces are performed to evaluate the impact of fat constitution on channel characteristics. It is found that similar tendency on fat propagation is seen in the evaluations with different methods. It is also observed that channel attenuation depends not only on the types and thicknesses of the tissues between transmitter and receiver antennas, but also how the tissues, especially fat, is located between the antennas. Channel attenuation difference between different voxels is maximum 14 dB in the studied antenna locations. Furthermore, propagation channel is evaluated with measurements using pork meat having different fat and muscle constitutions. It is found that antenna location respect to fat layers has clear impact on the channel strength although the fat tissue is not directly above the in-body antenna. The difference is noted to be 3–15 dB especially on the side peaks of channel impulse response. The knowledge on fat as a propagation medium is crucial when designing medical monitoring or implant communication systems. Location of antennas/sensor nodes for the monitoring devices can be established so that propagation through fat layer can be exploited

Propagation study of UWB capsule endoscope with multiple on-body antennas

Abstract This paper presents a study of the radio channel characteristics between a capsule endoscopy and a multi on-body antenna system on ultra wideband wireless body area networks (UWB-WBAN). Multiple on-body antennas are required to provide reliable communication link between the capsule and the on-body device, but also essential for capsule localization. The main aim is to study the variation of the frequency and time domain channel characteristics for the selected on-body antennas in different capsule locations, including the most challenging capsule locations deep inside the tissues or far away from most of the antennas. This study also evaluates whether five of selected type directive on-body antennas is enough to cover the intestine area thoroughly. The study is conducted with CST Studio Suite simulations and one of its anatomical voxel models. A simplified capsule model and a directive on-body antenna designed for low-band UWB in-body communications are used in this study. It is found that five of this type directive on-body antennas provide sufficient coverage over the intestine area even in the most challenging capsule locations. In certain capsule locations, the variation between the channel attenuations can be significant, over 40 dB within the frequency range of interest, if the capsule is located deep inside the tissues without smooth access to outer fat layer through which the signal could travel easily to different on-body antennas. Instead, if the capsule is located close to the subcutaneous fat layer, the channel attenuation is moderate even for the antennas which are located far from the capsule

Radio channel study for colon capsule endoscopy with low-band UWB multiple antenna system

Abstract This paper presents a study of the radio channel characteristics between a colon capsule endoscope and a multiple on-body antenna system in ultra wideband wireless body area networks (UWB-WBAN). The main aim is to study the variation of the channel characteristics for the on-body antennas in different capsule locations throughout the whole colon area. The study is conducted with CST Studio Suite simulations and one of its anatomical voxel models. A simplified capsule model and directive on-body antennas designed for low-band UWB in-body communications are used. It is found that five of this type directive on-body antennas provide sufficient coverage over the whole colon are even in the most challenging capsule locations

On the UWB in-body propagation measurements using pork meat

Abstract This paper presents a study on the in-body propagation using pork meat at the lower ultrawideband (UWB) frequency band 3.74—4.25 GHz of the wireless body area network (WBAN) standard 802.15.6. Pork meat in terms of the dielectric properties is one of the most similar to human tissues and thus is commonly used in in-body propagation studies. Nevertheless, there are differences in the dielectric properties, creating some differences also in the radio propagation. The first objective of this paper is to investigate by simulations the propagation differences between human and pork tissue layer models. The simulations results show clear differences between the channel characteristics obtained using a human tissues and pork tissues: within the frequency range of interest, the path loss with pork meat can be up to 5 dB less than with the human meat. The second objective of this paper is to study, by measurements, the in-body channel characteristics using different types of pork meat piece having different fat and muscle compositions. It was found that path loss is clearly higher with the pork meat having separate skin, fat, and muscle layers compared to the pork meat having interlaced fat and muscle layers. Furthermore, the third objective of this paper is to study the impact of the meat temperature on the measured channel characteristics by comparing the channels obtained with the meat at the temperatures of 12 °C and at 37 °C. Also, in this case clear differences were observed in path loss: within the frequency range of interest, the path loss was maximum 5 dB lower with meat at 37 °C than with a colder meat. The results presented in this paper provide useful information and relevant aspects for the in-body propagation studies conducted with pork meat

Modeling of a Public Safety Communication System for Emergency Response

This paper describes simulation work in modeling a city-wide trunked radio system and evaluating its performance under stress. Specifically, traffic models are developed to simulate both routine background traffic and the traffic load associated with an emergency scenario of a high-rise apartment fire. An analysis of a one-month radio data log provided insights on the traffic distribution among different talk-groups, as well as building individual traffic loading profiles for the talk-groups directly involved in the emergency response. The performance of the radio system is evaluated under different traffic loading intensity levels. Initial simulation results show that this emergency response communication system provides adequate capacity even under intense traffic loading. However, one area of concern is the build-up of waiting calls within some heavily loaded talk-group, which results in long waiting time to access the channel

Coexistence of wireless technologies in medical scenarios

Abstract The goal of this paper is to provide a comprehensive overview of the coexistence nature of wireless technologies most likely to be found in medical scenarios’ environment. The diversity and number of these technologies is increasing constantly leading to potential interference problems and performance degradation of wireless medical applications which are expected to become popular in 5G systems. The industrial, scientific and medical (ISM) bands in the 2.4 GHz are already very crowded to the point that the location and use of medical devices have to take into account the pervasive presence of other wireless devices operating in that region of the spectrum. A temporary solution is to use more the 5 GHz bands currently not so heavily utilized. This scenario will change in the near future as unlicensed long-term evolution (LTE) solutions such as MulteFire start operating in those bands. This paper provides a summary of the wireless technologies and devices present in hospitals and other medical care scenarios. It also provides recommendations for the rational share of the spectrum in those scenarios

In-body propagation at ISM and UWB frequencies for abdominal monitoring applications

Abstract This paper presents the results of an in-body propagation study for abdominal implant communication using a bio-matched mini-horn antenna. The wireless signal coverage in the abdomen area at various ISM and UWB frequency bands are measured using electromagnetic simulations with a 3D anatomical voxel model. Power flow analysis is conducted to visualize propagation within the abdominal tissues at several frequencies. As an example, S-Parameters of the channel between a capsule endoscopy pill and an on-body receiver has been studied and channel attenuations at different frequencies are compared. Using the directional bio-matched antenna, it is observed that at 915 MHz the signal coverage in a horizontal plane is sufficient to almost include the whole small intestine. However, the depth of the coverage reduces substantially at higher frequency bands. This comparative analysis can provide some insight on the applicability of these frequencies for various abdominal monitoring applications. It can also provide some information about the required number and placement of the on-body receivers in order to ensure adequate signal reception