Wireless Technologies
The wireless world continues to grow as engineers develop faster, more robust technologies to free us from wires for greater simplicity, convenience, and efficiency. From short range to long range, the wireless landscape has taken shape in our lives. A comparison of the various wireless technologies is helpful when deciding which technology to implement or products to purchase (special attention has been paid to the automotive application domain).
Bluetooth: Bluetooth is a short-range radio frequency standard for wireless communication between devices which permit transmission speeds up to 3Mbits/sec between devices within a 30-foot range of one another. It was initially developed as a personal area network protocol for low-power, short-range wireless peer-to-peer connection. However, its applicability for interconnecting several communication and electronic devices within a vehicle under the harsh automotive conditions has resulted in its rapid adoption by the automakers globally for supporting hands-free calling.
WiFi: WiFi is the short-form for Wireless Fidelity and is the trademark for product compatibility standards for wireless local area networks. Although it was initially developed for connecting mobile devices with local area networks, its applicability for supporting a host of automotive applications is being actively investigated by the automotive industry participants in North America. It is being perceived as the wireless protocol that holds the potential of significantly enhancing the inter-vehicular communication capabilities of the next generation of vehicles offered in the North American light vehicle market.
WiMax: WiMax is a wireless technology that offers high data throughput over long distances within a metropolitan area, and is designed to complement WiFi, wired Ethernet, token ring, and cable modems, which use the same logical link control. While WiFi’s network range is covered in square meters, WiMax’s range is expressed in square miles. WiMax is the commercial name for the IEEE 802.16 networks that enable the vehicle to be connected with other vehicles and stationary information centers within a metropolitan area while it is on the move and within the range of the WiMax coverage area.
UWB: Ultra-Wideband (UWB) is a short-range wireless communications technology which can be applied in vehicles to greatly reduce wiring between electronic systems and offer high-speed, high-bandwidth data transfer link to outside information and information sources. While Bluetooth offers a maximum of 3 Mbits/sec, UWB in comparison features network speeds of 50-100 Mbits/sec and in short ranges it can support data speeds of almost 480 Mbits/sec.
ZigBee: Zigbee is a published specification set of high level communication protocols designed to use small, low power digital radios based on the IEEE 802.15.4 standard for wireless personal area networks (WPANs). Zigbee is considered to be an ideal wireless protocol for short message applications like sensors and controls and nodes can be placed in a larger area as compared to that in Bluetooth networks. Connecting sensors using Zigbee can reduce wiring complexities and also result in cost-savings by facilitating re-configuration and eliminating the need for re-wiring once installed.
Wireless USB: Wireless USB is an extension to the USB and ultra-wide band technologies. It enables the universal serial bus networking in a wireless manner thereby reducing wiring complexities and thereby enabling effective portable device connectivity with the vehicle’s infotainment systems. The wireless USB technology supports a dual-role model where a device is also allowed to offer limited host capabilities thereby enabling mobile devices to access services with a central host supporting the services and also allowing devices to access data outside a cluster by creating a second cluster as a limited host.