Vehicle to vehicle (V2V) wireless communications

This work focuses on the vehicle-to-vehicle (V2V) communication, its current challenges, future perspective and possible improvement.V2V communication is characterized by the dynamic environment, high mobility, nonpredective scenario, propagation effects, and also communicating antenna's positions. This peculiarity of V2V wireless communication makes channel modelling and the vehicular propagation quite challenging. In this work, firstly we studied the present context of V2V communication also known as Vehicular Ad-hoc Netwok (VANET) including ongoing researches and studies particularly related to Dedicated Short Range Communication (DSRC), specifically designed for automotive uses with corresponding set of protocols and standards. Secondly, we focused on communication models and improvement of these models to make them more suitable, reliable and efficient for the V2V environment. As specifies the standard, OFDM is used in V2V communication, Adaptable OFDM transceiver was designed. Some parameters as performance analytics are used to compare the improvement with the actual situation. For the enhancement of physical layer of V2V communication, this work is focused in the study of MIMO channel instead of SISO. In the designed transceiver both SISO and MIMO were implemented and studied successfully

Co-Channel Interference Between IEEE 802.11 WLAN and Bluetooth

Electrical Engineering Technolog

PERFORMANCE STUDY FOR CAPILLARY MACHINE-TO-MACHINE NETWORKS

Communication technologies witness a wide and rapid pervasiveness of wireless machine-to-machine (M2M) communications. It is emerging to apply for data transfer among devices without human intervention. Capillary M2M networks represent a candidate for providing reliable M2M connectivity. In this thesis, we propose a wireless network architecture that aims at supporting a wide range of M2M applications (either real-time or non-real-time) with an acceptable QoS level. The architecture uses capillary gateways to reduce the number of devices communicating directly with a cellular network such as LTE. Moreover, the proposed architecture reduces the traffic load on the cellular network by providing capillary gateways with dual wireless interfaces. One interface is connected to the cellular network, whereas the other is proposed to communicate to the intended destination via a WiFi-based mesh backbone for cost-effectiveness. We study the performance of our proposed architecture with the aid of the ns-2 simulator. An M2M capillary network is simulated in different scenarios by varying multiple factors that affect the system performance. The simulation results measure average packet delay and packet loss to evaluate the quality-of-service (QoS) of the proposed architecture. Our results reveal that the proposed architecture can satisfy the required level of QoS with low traffic load on the cellular network. It also outperforms a cellular-based capillary M2M network and WiFi-based capillary M2M network. This implies a low cost of operation for the service provider while meeting a high-bandwidth service level agreement. In addition, we investigate how the proposed architecture behaves with different factors like the number of capillary gateways, different application traffic rates, the number of backbone routers with different routing protocols, the number of destination servers, and the data rates provided by the LTE and Wi-Fi technologies. Furthermore, the simulation results show that the proposed architecture continues to be reliable in terms of packet delay and packet loss even under a large number of nodes and high application traffic rates

Pedestrain Monitoring System Using Wi-Fi Technology and RSSI Based Localization

This paper presentsa new simple mobile tracking system based on IEEE802.11 wireless signal detection, which can be used for analyzingthe movement of pedestrian traffic. Wi-Fi packets emitted by Wi-Fi enabled smartphones are received at a monitoring station and these packets contain date, time, MAC address, and other information. The packets are received at a number of stations, distributed throughout the monitoring zone, which can measure the received signal strength. Based on the location of stations and data collected at the stations, the movement of pedestrian traffic can be analyzed. This information can be used to improve the services, such as better bus schedule time and better pavement design. In addition, this paper presents a signal strength based localization method

Performance Analysis of Bluetooth Network in the Presence of WI-FI System

Many wireless technologies used to build local or personal area network (WLANs or WPANs) operate in the 2.4 GHz ISM band. Due to mutual interference, the coexistence of such devices working at the same time in the same area can be troublesome. This paper reports the result of Bluetooth performance  with 802.11b interference in term of BER of Bluetooth network. This study employed Agilent Advance Design system 2011 (ADS 2011) as methodology. The result revealed how Bluetooth network suffered degradation in terms of BER and the IEEE 802.11b interfering power and frequency offset. This study confirm previous finding. Further, the study recommends that the data rate of IEEE 802.11b should be taken into account in the performance evaluation of the Bluetooth network. Keywords: Bluetooth, Performance, and WI-FI syste

Viterbi Decoding for OFDM systems operating in narrow band interference

Our main objective in this thesis is to study the effect of narrow band interference on OFDM systems operating in the 2.4 Ghz ISM band and identify ways to improve upon existing techniques to deal with them. We first consider how narrow band signals interfere with OFDM systems. Various noise variance estimation and signal to noise ratio estimation techniques for OFDM systems are then discussed. We also study the conventional Viterbi Algorithm that is used in OFDM wireless systems and the proposed modifications to it in the literature. Our main contribution is a detailed experimental analysis of a modified Viterbi Algorithm that outperforms the conventional one in the presence of narrow band interference. Interference samples captured using a wireless hardware platform were used in simulation to test this modified algorithm. From our analysis we realize that in the presence of narrow band frequency selective interference (such as Bluetooth), the conventional Viterbi Algorithm can be modified to improve the performance of OFDM systems