A case for wireless broadband "readiness" in worldwide markets

The key difference from first-generation wireless broadband is that today's networks use technologies such as adaptive beamforming and multi-carrier synchronous CDMA. Instead of blasting a signal in all directions, adaptive beamforming works like a flashlight, with smart antennas focusing power and capacity exactly where it's needed. By constantly monitoring the air link or beam to each user, the system constantly optimizes each connection. Even when conditions change and users move, the path loss is kept to an absolute minimum.

Adaptive beamforming provides up to 64 times more power efficiency than a single-carrier system, thereby allowing the use of lower-cost power amplifiers. The network's adaptive beamforming is complemented by diversity receivers in the CPE. This combination eliminates the need for an outdoor antenna and allows the CPE to shrink to the size of a PCMCIA card. That change means that wireless broadband can now provide the Wi-Fi experience in a wide-area context.

To address scaling issues, synchronous CDMA has a frequency re-use factor of N=1, meaning the same frequency can be re-used by adjacent sites and even within the same site, thereby reducing overhead.

With the addition of portability, wireless broadband WAN solutions is now the technology best able to offer high-speed data at work, at home and everywhere in between. Wi-Fi has whetted consumers' and enterprise users' appetites for broadband, and WANs leverage that appetite by letting them enjoy that freedom and power in even more places.

From technical and business perspectives, wireless broadband WANs are ideal for covering large geographic areas. A single WAN site can cover several miles. Fewer sites means lower up-front and maintenance costs. A site also can be co-located on a cellular tower, which already has T1 access. As a result, an operator can deploy ubiquitous service to an entire market faster and less expensively than with Wi-Fi, which requires thousands of access points, each with its own T1 backhaul and maintenance costs, to cover the same geography.

The operational costs alone undercut the business case for using Wi-Fi to cover more than limited areas such as hot spots, campuses and office buildings. Wi-Fi and wireless broadband WANs serve different needs, so they're better viewed as complementary than competitors. In fact, we envision a world where you can seamlessly roam from a hotspot to a "hot zone" covered by a wireless broadband WAN and back again with no effort on the part of the user, thus providing concentric rings of broadband coverage.

Wireless broadband can be deployed at multiple frequencies, including the licensed 2.3 GHz WCS, 2.5/2.6 GHz ITFS/MMDS bands and the unlicensed 2.4 GHz ISM band. Protection from interference is particularly important if the service is marketed to business users, who demand quality of service. Sophisticated interference-mitigation techniques let carriers deploy broadband wireless in unlicensed spectrum.

Wireless broadband isn't the only technology hamstrung by expensive installs, limited range and poor scalability. But unlike cable, DSL, 3G and Wi-Fi, wireless broadband has overcome those limitations. That puts it in the best possible position to tap the growing market for broadband in North America and abroad.