| At the high end of short range wireless connectivity can be found standards such as HiperLan2 and the upcoming 802.11A specification that operate in the 5GHz band. These are targeted for high bit-rate data transfer needs such as streaming video and wireless hot-spots.
At the middle level of cost and performance reside several standards: 802.15.1 Bluetooth, 802.11BWiFi and HomeRF.
Bluetooth enjoys the support of more than a thousand leading companies, including cellular phone manufacturers Nokia and Ericsson, which will provide a huge install base of Bluetooth technology in cellular phones. Bluetooth is becoming a de-facto standard for wireless connectivity among cellular phones, PDAs, notebook computers and PCs.
HomeRF, enjoys a robust architecture, based on the SWAP specification - a derivative of the 802.11 wireless LAN standard, and seems to be better suited for home applications.
At a higher price range you find WiFi, targeted more at office use than home networks. WiFi is essentially a seal of approval that the manufacturers product is compliant with IEEE 802.11B. This specification focuses on Direct Sequence because of the higher data rate that it can attain. It offers high data speed but that can fluctuate significantly. 802.11b currently has the largest installed base among short-range wireless technologies.
All standards are inadequate for various lower-end applications (such as home and industrial automation, security systems and toys) due to high power consumption, complex architecture and relatively high costs ($8-$15 per module in the long run).
At the low end, various narrow band technologies are used for a wide array of applications. These technologies will have a hard time migrating into the ISM (2.4GHz) band and will not be of much use in a transmission rich environment, due to their inability to deal with interference. This leaves an intermediate area of applications that is still uncovered by existing technologies. This area is targeted by RFWaves, offering 1Mbps, spread-spectrum transceivers, at a substantially lower price than Bluetooth.
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