The two dominant 3G standards, WCDMA and CDMA2000, look set to converge in LTE. With one or two exceptions, almost all operators of 3G mobile networks are indicating that they will move to LTE over time. Interestingly, CDMA2000 operators are more likely to be early adopters of LTE, since GSM/WCDMA operators have typically only recently made major investments into CDMA-based platforms, and may prefer to delay the next major upgrade, remaining with HSPA/HSPA+ a bit longer.
Although WiMAX showed some early promise as a possible mobile standard, it is rapidly becoming a footnote in the history of mobile communications. WiMAX has found a niche, as in South Africa and similar developing countries, as a wireless alternative to wireline broadband services, where these services are limited or unavailable. It's likely to remain in this niche for now, but will become increasingly difficult to justify when LTE networks are deployed.
There's nothing particularly flawed about the WiMAX standard on paper - it's very similar to LTE at the radio interface - but that's not how these things work. The real drivers of standards today are major carriers and their network suppliers, as well as the chipset vendors who determine terminal designs. Dual-mode and multi-band WCDMA/CDMA2000 chipsets are common today, and adding LTE to these chipsets is on all the roadmaps. WiMAX, where it has been implemented on multi-mode terminals, is a separate add-on, using a separate chipset. We will simply never see the vast array of standard terminals on WiMAX that we see today on the two 3G standards. Similarly, where LTE is the standard upgrade path for WCDMA/CDMA2000 networks, WiMAX would typically have to be a completely separate build. Viewed together, these facts limit the potential of WiMAX to a few niches, far removed from the original vision.
