iBurst

iBurst (or HC-SDMA, High Capacity Spatial Division Multiple Access) is a wireless broadband technology developed by ArrayComm. It optimizes the use of its bandwidth with the help of smart antennas. Kyocera is the leading manufacturer of iBurst devices.
iBurst is a mobile broadband wireless access system that was first developed by ArrayComm, and subsequently adopted as the High Capacity – Spatial Division Multiple Access (HC-SDMA) radio interface standard (ATIS-0700004-2005) by the Alliance of Telecommunications Industry Solutions (ATIS). The standard was prepared by ATIS’ Wireless Technology and Systems Committee’s (WTSC) Wireless Wideband Internet Access subcommittee and has been accepted as an American National Standard.
The HC-SDMA interface provides wide-area broadband wireless data-connectivity for fixed, portable and mobile computing devices and appliances. The protocol is designed to be implemented with smart antenna array techniques to substantially improve the radio frequency (RF) coverage, capacity and performance for the system. In January 2006, the IEEE 802.20 Mobile Broadband Wireless Access Working Group adopted a technology proposal that includes the use of the HC-SDMA standard for the 625kHz Multi-Carrier Time Division Duplex (TDD) mode of the future IEEE 802.20 standard. One Canadian vendor operates at 1.8 GHz.
HC-SDMA is also being incorporated by ISO TC204 WG16 into its standards for use of wireless broadband systems in the continuous communications standards architecture, known as CALM, which ISO is developing for intelligent transport systems (ITS). ITS may include applications for public safety, congestion management during traffic incidents, automatic toll booths, and more. An official liaison has been established between WTSC and ISO TC204 WG16 for this purpose.

Technology
The HC-SDMA interface operates on a similar premise as GSM or CDMA2000 for cellular phones, with hand-offs between HC-SDMA cells reportedly providing the user with a seamless wideband wireless experience even when moving at the speed of a car or train.
The protocol:
• specifies base station and client device RF characteristics, including output power levels, transmit frequencies and timing error, pulse shaping, in-band and out-of band spurious emissions, receiver sensitivity and selectivity;
• defines associated frame structures for the various burst types including standard uplink and downlink traffic, paging and broadcast burst types;
• specifies the modulation, forward error correction, interleaving and scrambling for various burst types;
• describes the various logical channels (broadcast, paging, random access, configuration and traffic channels) and their roles in establishing communication over the radio link; and
• specifies procedures for error recovery and retry.
The protocol also supports Layer 3 (L3) mechanisms for creating and controlling logical connections (sessions) between client device and base including registration, stream start, power control, handover, link adaptation, and stream closure, as well as L3 mechanisms for client device authentication and secure transmission on the data links. Currently deployed iBurst systems allow connectivity up to 1 Mbit/s for each subscriber equipment. Apparently there will be future firmware upgrade possibilities to increase these speeds up to 5 Mbit/s, consistent with HC-SDMA protocol.
Figure 1 is common access and transport network, click the figure below to see enlarge.

Commercial use
Four access options are already commercially available using:
• Desktop modem with USB and Ethernet ports (with external power supply)
• Portable USB modem (using USB power supply)
• Laptop modem (PC card)
• DOVADO Wireless Residential Gateway (WRG) in combination with Laptop modem[1]
iBurst is commercially available in ten countries: Australia, South Africa, Azerbaijan, Norway, Ireland, Canada, Malaysia, Lebanon, Kenya, Ghana, and USA. Companies in Southeast Europe and the Middle East are also looking to roll out the service.

The overview taken from wikipedia for the further reading you can see from the wikipedia page and iBurst overview in pdf file by ArrayComm, Incorporated.