Received Signal Strength Ratio Research Articles

A Novel and Adaptive Angle Diversity-Based Receiver for 6G Underground Mining VLC Systems.

Visible light communication (VLC) is considered an enabling technology for future 6G wireless systems. Among the many applications in which VLC systems are used, one of them is harsh environments such as Underground Mining (UM) tunnels. However, these environments are subject to degrading environmental and intrinsic challenges for optical links. Therefore, current research should focus on solutions to mitigate these problems and improve the performance of Underground Mining Visible Light Communication (UM-VLC) systems. In this context, this article presents a novel solution that involves an improvement to the Angle Diversity Receivers (ADRs) based on the adaptive orientation of the Photo-Diodes (PDs) in terms of the Received Signal Strength Ratio (RSSR) scheme. Specifically, this methodology is implemented in a hemidodecahedral ADR and evaluated in a simulated UM-VLC scenario. The performance of the proposed design is evaluated using metrics such as received power, user data rate, and bit error rate (BER). Furthermore, our approach is compared with state-of-the-art ADRs implemented with fixed PDs and with the Time of Arrival (ToA) reception method. An improvement of at least 60% in terms of the analyzed metrics compared to state-of-the-art solutions is obtained. Therefore, the numerical results demonstrate that the hemidodecahedral ADR, with adaptive orientation PDs, enhances the received optical signal. Furthermore, the proposed scheme improves the performance of the UM-VLC system due to its optimum adaptive angular positioning, which is completed according to the strongest optical received signal power. By improving the performance of the UM-VLC system, this novel method contributes to further consideration of VLC systems as potential and enabling technologies for future 6G deployments.

High-Accuracy Height-Independent 3D VLP Based on Received Signal Strength Ratio.

Visible light positioning (VLP) has attracted intensive attention from both academic and industrial communities thanks to its high accuracy, immunity to electromagnetic interference, and low deployment cost. In general, the receiver in a VLP system determines its own position by exploring the received signal strength (RSS) from the transmitter according to a pre-built RSS attenuation model. In such model-based methods, the LED’s emission power and the receiver’s height are usually required known and constant parameters to obtain reasonable positioning accuracy. However, the LED’s emission power is normally time-varying due to the fact that the LED’s optical output power is prone to changing with the LED’s temperature, and the receiver’s height is random in a realistic application scenario. To this end, we propose a height-independent three-dimensional (3D) VLP scheme based on the RSS ratio (RSSR), rather than only using RSS. Unlike existing RSS-based VLP methods, our method is able to independently find the horizontal coordinate, i.e., two-dimensional (2D) position, without a priori height information of the receiver, and also avoids the negative effect caused by fluctuation of the LED’s emission power. Moreover, we can further infer the height of the receiver to achieve three-dimensional (3D) positioning by iterating the 2D results back into positioning equations. To quickly verify the proposed scheme, we conduct theoretical analysis with mathematical proof and experimental results with real data, which confirm that the proposed scheme can achieve high position accuracy without known information of the receiver’s height and LED’s emission power. We also implement a VLP prototype with five LED transmitters, and experimental results show that the proposed scheme can achieve very low average errors of 2.73 cm in 2D and 7.20 cm in 3D.

A High-Coverage Camera Assisted Received Signal Strength Ratio Algorithm for Indoor Visible Light Positioning

A high-coverage algorithm termed enhanced camera assisted received signal strength ratio (eCA-RSSR) positioning algorithm is proposed for visible light positioning (VLP) systems. The basic idea of eCA-RSSR is to utilize visual information captured by the camera to estimate first the incidence angles of visible lights. Based on the incidence angles, eCA-RSSR utilizes the received signal strength ratio (RSSR) calculated by the photodiode (PD) to estimate the ratios of the distances between the LEDs and the receiver. Based on an Euclidean plane geometry theorem, eCA-RSSR transforms the ratios of the distances into the absolute values. In this way, eCA-RSSR only requires three LEDs for both orientation-free 2D and 3D positioning, implying that eCA-RSSR can achieve high coverage. Based on the absolute values of the distances, the linear least square method is employed to estimate the position of the receiver. Therefore, for the receiver having a small distance between the PD and the camera, the accuracy of eCA-RSSR does not depend on the starting values of the non-linear least square method and the complexity of eCA-RSSR is low. Furthermore, since the distance between the PD and camera can significantly affect the performance of eCA-RSSR, we further propose a compensation algorithm for eCA-RSSR based on the single-view geometry. Experiment results show that positioning errors of less than five centimeters is achievable for eCA-RSSR. Simulation results show that eCA-RSSR can achieve 80th percentile accuracy of about four centimeters and can improve the coverage ratio at low cost.

Camera Assisted Received Signal Strength Ratio Algorithm for Indoor Visible Light Positioning

A novel camera assisted received signal strength ratio (CA-RSSR) positioning algorithm is proposed for visible light positioning (VLP) systems. The basic idea of CA-RSSR is to utilize visual information captured by the camera first, to analyze the geometric relations among the light-emitting diodes (LEDs) and the receiver. Based on the visual information, the photodiode (PD) can locate the receiver by the signal strength of visible lights. Due to the combination of visual and strength information of visible light signals, CA-RSSR can mitigate the receiver orientation limitation in conventional received signal strength (RSS) algorithms. In addition, the positioning accuracy of CA-RSSR is significantly better than perspective-n-point (PnP) algorithms, which achieves positioning function based on visual information only. Simulation results show that the proposed approach can achieve an 80th percentile accuracy of around 12 cm over 85% indoor area regardless of the receiver orientations, which is better than the conventional RSS and PnP algorithms.

A Link Distribution Algorithm with Efficient Relay Node Optimization for Congestion Control in Urban Vanets

This research work develops a new algorithm i.e. Link distribution algorithm and efficient link distribution algorithm. A Link distribution algorithm is the distribution of the link to the nodes so that communication between the nodes takes place in case of any link failure whereas efficient link distribution algorithm is distribution of the packets to the nodes which has high transmission power. The technique used in Link distribution algorithm (LDA) is link establishment whenever there is any link failure happen we apply this concept which is LDA whereas the technique used in efficient link distribution algorithm (ELDA) is relay node selection the relay node is selected based upon the received signal strength ratio (RSSI) value and which node is having high RSSI value that node we allocate the link. The above algorithms can be applied wherever there is high congestion on the road due to the high congestion link failure will happen and due to the link failure emergency event occurs. Results of model achieved in a realistic state of affairs validate our theoretical deliberation and confirm the efficiency and the efficacy of our protocol by screening significant expansion in terms of busy ratio, collision rate, deviation, local density and transmission power compared to previous scheme ETSI DCC. The work has been successfully done with the help open source network simulator NS3.

Improved Received Signal Strength Ratio Based High Accuracy Indoor Visible Light Positioning Scheme

Improved Received Signal Strength Ratio Based High Accuracy Indoor Visible Light Positioning Scheme

A Probabilistic Broadcasting Mechanism based on Cross Layer Model Deliberating Received Signal Strength Ratio in Mobile Ad Hoc Networks

Mobile Ad Hoc Networks(MANETs) consists of mobile nodes which communicate with each other without any centralized infrastructure. Message broadcasting by flooding for route discovery in MANET can result in high redundant retransmission, contention and collision of broadcasting packet, known as the broadcast storm problem collectively. The cross-layer design is adopted in this paper, which lets routing layer share the received signal strength information at MAC layer. Also this paper proposes a new probabilistic approach that dynamically adjusts the rebroadcasting probability of a node for routing request packets (RREQs) according to the received signal strength. The simulation results show that the proposed approach demonstrates better performance than blind flooding, fixed probabilistic broadcasting approaches.

A New Optimized Localized Technique of CG Return Stroke Lightning Channel in Forest

Localization of lightning strike point (LSP) in the forest is modeled to mitigate the forest fire damage. Though forest fire ignited by lightning rarely happens, its damage on the forest is grievousness. Therefore, predicting accurate location of LSP becomes crucial in order to control the forest fire. In this paper, we proposed a new hybrid localization algorithm by combining the received signal strength (RSS) and the received signal strength ratio (RSSR) to improve the accuracy by mitigating the environmental effect of lightning strike location in the forest. The proposed hybrid algorithm employs antenna theory (AT) model of cloud-to-ground (CG) return stroke lightning channel to forecast the location of the lightning strike. The obtained results show that the proposed hybrid algorithm achieves better location accuracy compared to the existing RSS method for predicting the lightning strike location considering additive white Gaussian noise (AWGN) environment.

Indoor location awareness based on received signal strength ratio and time division multiplexing using light-emitting diode light

We propose and demonstrate an indoor location awareness method for an autonomous robot vehicle using light-emitting diodes (LEDs). The location is estimated by measuring received signal strength ratio (RSSR), which is the relative ratio of optical powers detected between each LED and optical receiver. In this method, multiple LED lamps on the indoor ceiling are used, which can radiate light only during the individual time slot assigned to each of them. Using the RSSRs, circle or straight line equations are obtained and the crossing point among those equations determines the location of the object. In the experiment, four LED lamps are iden- tified by time-division multiplexing with room dimensions of 1.0 × 1.0 × 1.3 m 3 , and the results show that the mean of the location error is 3.24 cm in the entire floor area. © The Authors. Published by SPIE under a Creative Commons Attribution 3.0 Unported License. Distribution or reproduction of this work in whole or in part requires full attribution of the original publication, including

One-Dimensional Localization Algorithm Based on Signal Strength Ratio

Localization algorithm in wireless sensor networks has attracted significant interest in recent years. The RSSI approach is considered as the cheapest solution allowing coarse-grain, yet effective for many applications in outdoor environments. However, when environments change, there exists a big localization error using RSSI without a reconstructing data set. In order to solve the problem of reestablishing the data set when the environments change, a novel one-dimensional localization algorithm based on received signal strength ratio (1-DIM-RSSR) is proposed for the one-dimensional wireless sensor network applications, such as road surveillance and pipeline transmission. While synthetically considering accuracy, power consumption, localization time, and device costs, we can only use coordinate x to locate the nodes by defining y as 0. Our algorithm is based on the theory as follows: the values of Signal Strength vary from one environment to another. When environments change, even the distance between the transmitter and the receiver remains unchanged, but there is still at least 10dBm's difference. On the contrary, the ratio of the received signal strength from two base stations varies little in the condition of the unchanged distance, and thus it avoids reconstructing the dataset when environments change. 1-DIM-RSSR comprises of two phases: the data set construction phase and the localization phase. In the first phase, N reference nodes are uniformly distributed between the two base stations BS1 and BS2. We collect the signal strength RRi1 and RRi1 from BS1 and BS2 respectively and get signal strength ratio Ri = RRi1/RRi2 at each point, where i ϵ [1, N] corresponding to the N references nodes. In the localization phase, we record the signal strength ratio Rʹ of mobile nodes and pick the one that best matches the observed signal strength ratio. Our idea is to compute the distance | Ri - Rʹ| at a fixed set of locations, and then pick the location that minimizes the distance. Simulation and experiment results show that localization precision of the proposed algorithm compared with the RSSI algorithm is improved when the environments change. The proposed method is easy to operate, and need not reconstruct the dataset when the environments change. So this method holds the promise for many applications such as monitoring product lines, road surveillance, and pipeline transmission. Meanwhile, since our algorithm is based on 1-D localization, how to extend this conception to 2-D or even 3-D localization will be our ongoing work.