Bit error rate estimation in WiMAX communications at vehicular speeds using Nakagami-m fading model

The wireless communication industry has experienced a rapid technological evolution from its basic first generation (1G) wireless systems to the latest fourth generation (4G) wireless broadband systems. Wireless broadband systems are becoming increasingly popular with consumers and the technological strength of 4G has played a major role behind the success of wireless broadband systems. The IEEE 802.16m standard of the Worldwide Interoperability for Microwave Access (WiMAX) has been accepted as a 4G standard by the Institute of Electrical and Electronics Engineers in 2011. The IEEE 802.16m is fully optimised for wireless communications in fixed environments and can deliver very high throughput and excellent quality of service. In mobile communication environments however, WiMAX consumers experience a graceful degradation of service as a direct function of vehicular speeds. At high vehicular speeds, the throughput drops in WiMAX systems and unless proactive measures such as forward error control and packet size optimisation are adopted and properly adjusted, many applications cannot be facilitated at high vehicular speeds in WiMAX communications. For any proactive measure, bit error rate estimation as a function of vehicular speed, serves as a useful tool. In this thesis, we present an analytical model for bit error rate estimation in WiMAX communications using the Nakagami-m fading model. We also show, through an analysis of the data collected from a practical WiMAX system, that the Nakagami-m model can be made adaptive as a function of speed, to represent fading in fixed environments as well as mobile environments

IPv6 Operation for WAVE - Wireless Access in Vehicular Environments

International audienceThe IEEE WAVE protocol suite is providing commu- nications services to applications in vehicular networks, by way of promising support for two protocol stacks: the Wave Short Message Protocol (WSMP) and IPv6. While WSMP is developed within the IEEE 1609 family of standards, the authors of this paper assert, that considerations for IPv6 operation for WAVE are less developed, and several issues are left unaddressed by the current IEEE 1609 specifications. This paper reviews these issues and analyzes the main challenges in providing proper IPv6 operation for WAVE networks

Path loss modeling for vehicular system performance and communicaitons protocols evaluation

Vehicular communications are receiving considerable attention due to the introduction of the intelligent transportation system (ITS) concept, enabling smart and intelligent driving technologies and applications. To design, evaluate and optimize ITS applications and services oriented to improve vehicular safety, but also non-safety applications based on wireless systems, the knowledge of the propagation channel is vital. In particular, the mean path loss is one of the most important parameters used in the link budget, being a measure of the channel quality and limiting the maximum allowed distance between the transmitter (Tx) and the receiver (Rx). From a narrowband vehicular-to-vehicular (V2V) channel measurement campaign carried out at 5.9 GHz in three different urban environments characterized by high traffic density, this paper analyzes the path loss in terms of the Tx-Rx separation distance and fading statistics. Based on a linear slope model, values for the path loss exponent and the standard deviation of shadowing are reported. We have evaluated the packet error rate (PER) and the maximum achievable Tx-Rx separation distance for a PER threshold level of 10% according to the digital short-range communications (DSRC) specifications. The results reported here can be incorporated in an easy way to vehicular networks (VANETs) simulators in order to develop, evaluate and validate new protocols and systems architecture configurations under realistic propagation conditions.Fernández González, HA.; Rubio Arjona, L.; Reig, J.; Rodrigo Peñarrocha, VM.; Valero-Nogueira, A. (2013). Path loss modeling for vehicular system performance and communicaitons protocols evaluation. Mobile Networks and Applications. 18(6):755-765. doi:10.1007/s11036-013-0463-xS755765186Gallager B, Akatsuka H, Suzuki H (2006) Wireless communications for vehicle safety: radio link performance and wireless connectivity. IEEE Veh Technol Mag 1(4):4–24Rubio L, Reig J, Fernández H (2011) Propagation aspects in vehicular networks, Vehicular technologies. Almeida M (ed) InTechWang C-X, Vasilakos A, Murch R, Shen SGX, Chen W, Kosch T (2011) Guest editorial. Vehicular communications and networks – part I. IEEE J Select Areas Commun 29(1):1–6ASTM E2213-03 (2003) Standard specification for telecommunications and information exchange between roadside and vehicle systems – 5 GHz band Dedicated Short Range Communications (DSRC) Medium Access Control (MAC) and Physical Layer (PHY) specifications. American Society for Testing Materials (ASTM), West ConshohockenIEEE 1609 – Family of Standards for Wireless Access in Vehicular Environments (WAVE). [Online]. Available: http://www.standards.its.dot.govETSI TR 102 492–2 Part 2 (2006) Technical characteristics for Pan European Harminized Communications Equipment Operating in the 5 GHz frequency range intended for road safety and traffic management, and for non-safety related ITS applications, European Telecommunications Standard Institute (ETSI), Technical Report, Sophia Antipolis, FranceThe Car-to-Car Communication Comsortium (C2CC): http:/www.car-to-car.orgMecklenbräuker C, Molisch A, Karedal J, Tufvesson F, Paier A, Bernado L, Zemen T, Klemp O, Czink N (2011) Vehicular channel characterization and its implications for wireless system design and performance. IEEE Proc 99(7):1189–1212Ghafoor KZ, Bakar KA, Lloret J, Khokhar RH, Lee KC (2013) Intelligent beaconless geographical routing for urban vehicular environments. Int J Wireless Netw 19(3):345–362Ghafoor KZ, Lloret J, Bakar KA, Sadiq AS, Mussa SAB (2013) Beaconing approaches in vehicular ad hoc networks: a survey. Int J Wirel Pers Commun. Published Online (May 2013)Michelson DG, Ghassemzadeh SS (2009) New directions in wireless communications, Springer Science+Busines Media (Chapter 1)IEEE 802.11p (2010) Wireless LAN Medium Access Control (MAC) and Physical Layer (PHY) Specifications Amendment 6: Wireless Access in Vehicular Environments, Institute of Electrical and Electronic Engineers (IEEE), New York, USA.Karedal J, Czink N, Paier A, Tufvesson F, Moisch AF (2011) Path loss modeling for vehicle-to-vehicle communications. IEEE Trans Veh Technol 60(1):323–327Cheng L, Henty B, Stancil D, Bai F, Mudalige P (2007) Mobile vehicle-to-vehicle narrow-band channel measurement and characterization of the 5.9 GHz dedicated short range communication (DSRC) frequency band. IEEE J Select Areas Commun 25(8):1501–1516Cheng L, Henty B, Cooper R, Stancil D, Bai F (2008) Multi-path propagation measurements for vehicular networks at 5.9 GHz. IEEE Wireless Communications and Networking Conference, pp. 1239–1244Tan I, Tang W, Laberteaux K, Bahai N (2008) Measurement and analysis of wireless channel impairments in dsrc vehicular communications. IEEE International Conference on Communications, pp. 4882–4888.Campuzano AJ, Fernández H, Balaguer D, Vila-Jiménez A, Bernardo-Clemente B, Rodrigo-Peñarrocha VM, Reig J, Valero-Nogueira A, Rubio L (2012) Vehicular-to-vehicular channel characterization and measurement results. WAVES 4(1):14–24Kunisch J, Pamp J (2008) Wideband car-to-car radio channel measurements and model at 5.9 GHz. IEEE 68th Vehicular Technology Conference, pp. 1–5Gozalvez J, Sepulcre M (2007) Opportunistic technique for efficient wireless vehicular communications. IEEE Veh Technol Mag 2(4):33–39Zang Y, Stibor L, Orfanos G, Guo S, Reumerman H (2005) An error model for inter-vehicle communications in highway scenarios at 5.9 GHz. Proc. Int. Workshop on performance evaluation of wireless ad hoc, sensor, and ubiquitous networks, pp. 49–5

In-vehicle channel sounding in the 5.8-GHz band

The article reports vehicular channel measurements in the frequency band of 5.8 GHz for IEEE 802.11p standard. Experiments for both intra-vehicle and out-of-vehicle environments were carried out. It was observed that the large-scale variations (LSVs) of the power delay profiles (PDPs) can be best described through a two-term exponential decay model, in contrast to the linear models which are suitable for popular ultra-wideband (UWB) systems operating in the 3- to 11-GHz band. The small-scale variations (SSVs) are separated from the PDP by subtracting the LSV and characterized utilizing logistic, generalized extreme value (GEV), and normal distributions. Two sample Kolmogorov-Smirnov (K-S) tests validated that the logistic distribution is optimal for in-car, whereas the GEV distribution serves better for out-of-car measurements. For each measurement, the LSV trend was used to construct the respective channel impulse response (CIR), i.e., tap gains at different delays. Next, the CIR information is fed to an 802.11p simulation testbed to evaluate the bit error rate (BER) performance, following a Rician model. The BER results strongly vouch for the suitability of the protocol for in-car as well as out-of-car wireless applications in stationary environments.The article reports vehicular channel measurements in the frequency band of 5.8 GHz for IEEE 802.11p standard. Experiments for both intra-vehicle and out-of-vehicle environments were carried out. It was observed that the large-scale variations (LSVs) of the power delay profiles (PDPs) can be best described through a two-term exponential decay model, in contrast to the linear models which are suitable for popular ultra-wideband (UWB) systems operating in the 3- to 11-GHz band. The small-scale variations (SSVs) are separated from the PDP by subtracting the LSV and characterized utilizing logistic, generalized extreme value (GEV), and normal distributions. Two sample Kolmogorov-Smirnov (K-S) tests validated that the logistic distribution is optimal for in-car, whereas the GEV distribution serves better for out-of-car measurements. For each measurement, the LSV trend was used to construct the respective channel impulse response (CIR), i.e., tap gains at different delays. Next, the CIR information is fed to an 802.11p simulation testbed to evaluate the bit error rate (BER) performance, following a Rician model. The BER results strongly vouch for the suitability of the protocol for in-car as well as out-of-car wireless applications in stationary environments