A handover is the terminology used to define the seamless transfer of a wireless device from one base station to another without loss or interruption of service. A handover would be conducted when a user device is moving away from the area covered by one base station and entering the area covered by another.

This groundbreaking achievement is extraordinarily beneficial to both end-users as well as network operators. As mobile WiMAX deployments become more common, users will benefit from the ability to transfer from one operating network to another. For instance, in the United States, a user with an Airspan MiMAX USB device connected to their laptop may be able to roam from a license-exempt 3.65 GHz network into a national, license-owned 2.5 GHz WiMAX network.

Carriers and operators will benefit from the option to deploy a single, large mobile WiMAX network using two or more frequency bands. In many regions, the availably of 2.5 GHz is limited. Now operators can aggregate spectrum to allow significant expansion of coverage and roaming capabilities. A carrier, for example, could begin with a small allocation at 2.3 or 2.5 GHz and add a larger, often more affordable, allocation at 3.X GHz or even 5 GHz.

Users of wireless networks are typically confined to handovers within a single operating frequency band. Switching between bands with a cellular phone today, for example, requires changing networks and forces the user to drop their connection before they are able to restart on a new network for the new band. By enabling seamless handover between two frequencies, the showcased solution has demonstrated just how revolutionary WiMAX is proving to be. The demonstration network is using the Airspan HiperMAX base station in 3.6 GHz frequency band and the MacroMAXe base station in the 2.5 GHz band communicating with a MiMAX Q-Series quad-band USB device connected to a laptop roaming between the two base stations.

Staged in the UK, this achievement was performed with the collaboration of long-term customer and partner FREEDOM4 and strategic partners Starent Networks, using their Access Service Network (ASN) gateway for connection management, and Bridgewater Systems, using their subscriber management solution that delivers carrier-grade authentication, authorization, and accounting (AAA) services.

Graham Currier, Chief Operating Officer at FREEDOM4, stated, "Airspan's Quad-Band MiMAX device creates a new paradigm for European WiMAX operators. Airspan's technology allows us to combine the reach of the 2.6 GHz frequency band with our large block of 3.6 GHz to create a spectrum position that can deliver a true broadband experience for mobile users. We can deliver speeds and capacities many times greater than operators using evolved 3G HSPA technologies."

Paul Senior, Chief Technology Officer of Airspan, commented, "We are very pleased to have succeeded in this world's first demonstration with FREEDOM4. Confirming Airspan's WiMAX innovation and technology leadership position, this achievement permanently changes the landscape of mobile WiMAX and its possibilities."

This milestone is timely and relevant for European operators, as 2.5 GHz/2.6 GHz spectrum will be auctioned/allocated in almost all European countries over the next 24-26 months, and typically up to 50 MHz of 2.5 GHz TDD spectrum (suitable for WiMAX) is available. The 2.6 GHz auction in the UK will likely happen in the first half of 2009.

Although this particular handover demonstration operated between the 2.5 and 3.6 GHz bands, Airspan equipment can support this type of handover between all the major WiMAX bands -- 2.3, 2.5, 3.3, 3.4-3.6, 3.6-3.8, and 5 GHz bands.

Keywords: airspan networks inc, seamless handover, demonstration network, groundbreaking achievement, airn, seamless transfer, network carriers, frequency band, frequency bands, network operators, nasdaq, showcased, wireless networks, cellular phone, end users, 3G

By Robert Hoskins

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