1.7.2 Cellular Networks
Perhaps the largest competitor to WiMAX technologies, cellular networks have been deployed all over the world. The level of investment and infra- structure deployment has been one of the most extensive of any terrestrial wireless network in existence. Furthermore, paths to evolve to higher data rates that support mobility from the start and provide users with an expe- rience that approximates the wired connectivity they experience at home or at the office is expected to materialize as the technologies evolve. However, there are some disadvantages to cellular as compared to WiMAX:
Cost: The expense of procuring and deploying a cellular network infrastructure with the most advanced, high-data-rate technologies (such as HSDPA and 1xEVDO) today is substantially larger than a WiMAX-enabled solution. First, the cost of maintaining spectrum licenses for cellular bands is substantial. Furthermore, base station cost is about an order of magnitude more expensive to procure. Finally, the complexity of such a solution is significant especially when cellular providers must retrofit their older-generation net- works and maintain separate networks to ensure users without the latest equipment will be able to maintain access.
Original design: Cellular systems were originally designed for voice communications and as such have been augmented to support a variety of data applications. The CDMA and GSM core networks have also evolved to support IP-based communications, which has become the de facto standard today. However, WiMAX technologies are primarily IP-based and were designed to support data and voice applications from the beginning.
Throughput performance: Results in Ref. 8 suggest that, when all other system parameters remain equal (bandwidth, antenna
configuration, power), WiMAX technology outperforms both HSDPA and cdma2000 3xEVDO (three 1xEVDO channels) by 28%–96%.
While there are some clear disadvantages to cellular, its key advantage over WiMAX technology remains its large coverage footprint. However, some cellular service providers such as Sprint Corporation in the United States have announced plans to deploy WiMAX across their entire coverage foot- print as well. In this sense, WiMAX would be considered complementary to cellular. Many other carriers, especially those with heavy investments in the GSM/UMTS-WCDMA technology space, have not adopted the same coexistence strategy. Sprint’s success or failure in deploying WiMAX on a nationwide scale will likely affect similar companies’ strategies in dealing with WiMAX competition and deployment.
While the technologies presented in this section are expected to compete for users that WiMAX aims to serve currently, market forces could very well align these technologies with WiMAX in a strategy to further the deployment and use of the emerging wireless Internet architecture.
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