INVESTIGATION OF WI-FI INDOOR SIGNALS UNDER LOS AND NLOS CONDITIONS (original) (raw)

Development of Radio Wave Propagation Model in Indoor Non-Line-of-Sight (NLOS) Scenario

2015

To improve the performance of an indoor WLAN, it is very important to estimate specific received signal strength based on experimental and predicting data. As the design of building layouts and constructed building materials modernize and are complex, it is difficult to estimate the received signal strength values according to those building structure. For this reason, this research develops a new radio wave propagation model for indoor Non-Line-of-Sight (NLOS) scenarios with the help of TP-LINK router .In order to develop the proposed model, the free space model is modified by considering the influence of corridor conditions on each floor based on ray tracing technique at a carrier frequency range of 2.4GHz. Using this model, indoor received signal strength values can be estimated according to the geometrical plan in modeling of indoor radio wave propagation. The performance comparison of channel capacity is implemented with various frequency ranges using MATLAB programming langua...

An Investigation on the Effects of Wall Parameters on the Indoor Wireless Propagations

2007 5th Student Conference on Research and Development, 2007

The type of the construction materials of the interior walls of the indoor environments plays a great role in the propagation of the transmitted signals inside the buildings. A comparison of calculated and simulated Fresnel reflection and transmitted coefficients at 2.4 GHz and 900 MHz for a variety of typical exterior building surfaces has been achieved. The effect of the different types of wall on the path loss prediction had been conducted by using a ray tracing program with real time reflection and refraction phenomena.

Investigation of indoor propagation of WLAN signals

Indonesian Journal of Electrical Engineering and Computer Science

The propagation of radio waves inside a typical university building is investigated by simulation and measurements. The Line of sight (LOS) and Obstructed Line of sight (OLOS) propagation scenarios were considered. The received power from a WLAN access point operating at 2.45GHz was determined from the simulations and measurements at various positions, orientations, and heights of the Tx and Rx antennas. The path loss exponents were estimated from the obtained simulation and measurement results of the received power variation with distance. The obtained path loss exponent values were found between 1.15-1.63 for LOS propagation and 2.14-2.55 for OLOS.

Characterization of Indoor Propagation Properties and Performance Evaluation for 2.4Ghz Band Wi-Fi

SSRN Electronic Journal

Indoor wireless systems poses one of the biggest design challenges although it is the most flexible and easily deployable method of implementing Local Area Networks. This difficulty in predicting the propagation of radio frequency wave in indoor environments is caused by reflection, refraction, diffraction and scattering of signals due to closed proximities to furniture, walls, human beings, and reflectors like ceiling, mirrors and glasses. To help improve the user experience and guarantee good quality of service in indoor situations, the research investigated the throughput and attenuation effect on signal with respect to 4, 5, 6 and 9 inches sizes of blocks walls respectively. The characterized Path-loss exponent was 1.999 and differed from the free space model, Wall and Floor Factor model and ITU model by 53.54dB, 6.42dB and 6.85dB respectively.

STUDY OF VARIOUS INDOOR PROPAGATION MODELS

Indoor Propagation modeling is demanded for the maintenance of indoors-wireless services. Propagation models provide estimates of signal strength and time dispersion in many indoor environments. These data are valuable in the design and installation of indoor radio systems. We propose improving existing channel models by building partitioning technique. Based on the measurement results the easy-to-use empirical propagation predication models were derived for both of the buildings with satisfactory accuracy. The result used to determine the path loss exponent and standard deviation. It similarly shows that the RSS values Vs distance help in determine the variation in multi-wall model and single wall.

D-Model: A new perspective for modeling radio signal propagation in indoor environment

There are different approaches towards estimating the signal strength in indoor environment, which includes models such as empirical and deterministic models. Empirical Models are simple but less accurate whereas deterministic models have more accuracy but much more complex. In this paper we have identified some limitations of the most widely used empirical model i.e. 'Wall Attenuation Model' and presented a new empirical model called 'D-Model' to reduce the errors in earlier empirical models. D-model proposed that a single wall do not always attenuate the signal with constant dB loss but it varies with the distance of transmitter as well. D-model considers the wall not as a constant attenuation element but as an increase in the transmitter to receiver distance with a factor called 'D-factor'. We proved that D-model gives much more accurate signal strength estimations as compared to Wall Attenuation Model.

Empirical Investigation of Indoor NLOS Propagation at

The growth in the communication industry demands a high bandwidth capacity to cope with the multimedia application services. The lower frequency bands allocated for communication, apart from being congested, is also incapable of the gigabits throughput delivery needed for the various applications. Therefore, it is highly imperative to engage the millimeter wave frequency bands to provide the adequate frequency spectrum. The peculiarities of the millimeter wave propagation are challenges to achieve this goal. This work conducted empirical measurements of the indoor propagation performances of 24 and 60GHz frequency bands. The results show that 24GHz band performs better in NLOS propagation than 60GHz hence, WLAN with gigabits throughputs can be deployed within offices in a modern building using the 24GHz Ubiquity Air fiber ptp links.

IJERT-Indoor Measurement And Propagation Prediction Of WLAN At 2.4GHz

International Journal of Engineering Research and Technology (IJERT), 2013

https://www.ijert.org/indoor-measurement-and-propagation-prediction-of-wlan-at-2.4ghz https://www.ijert.org/research/indoor-measurement-and-propagation-prediction-of-wlan-at-2.4ghz-IJERTV2IS70411.pdf With the low cost and high-speed data rate capabilities, installations of IEEE 802.11-based wireless local area networks (WLANs) are growing exponentially. Most wireless access points are deployed in the immediate vicinity of where wireless coverage is desired and the system typically seems to work. The performance of such an ad-hoc deployed network is much less than what could be achieved by proper network design. Indeed, many organizations are already noticing the actual data rate limitations of large scale, highly loaded WLANs that have been installed in an ad-hoc fashion. To assist in optimal deployment of indoor wireless system, characterization of the indoor radio propagation channel is essential. This project achieves this by carrying out extensive field strength measurements at different coverage angles in an already existing IEEE 802.11g WLAN network at 2.4GHz. Based on the statistics of the measured data, empirical propagation channel model is developed. By using this propagation model, network analysis and simulations can be efficiently carried out. This will facilitate faster and more accurate deployment of wireless networks.

Bringing It Indoors: A Review of Narrowband Radio Propagation Modeling for Enclosed Spaces

IEEE Access

Small cells are now widely deployed indoors to address hot-spot areas where capacity uplift is needed. This deployment leads to the increase of wireless networks as a challenge to service demands of personal communication systems, which has inspired the scientific community to work towards understanding and predicting in-building radio wave propagation performance. Despite this, only a few reviews have attempted to overview channel modeling for specific indoor environments and even fewer outline remarks that include a methodology for designing and planning indoor radio systems. Consequently, a comprehensive survey of indoor narrowband channel models is presented, spanning more than 30 years of continuous research to overview and contrast significant developments including their disadvantages, and proposing a new taxonomy to analyze them. Finally, remarks on indoor radio propagation modeling with a vision for future research opportunities are presented.