Techopedia Explains Ultra Mobile Broadband (UMB)
UMB features Orthogonal Frequency Division Multiple Access (OFDMA) as its air access method, which is a huge improvement over its forerunner, CDMA. It no longer requires a device to be in the line of sight to provide connectivity, thus expanding its wireless access system. OFDMA is resilient to interference, like CDMA, but is more robust and efficient.
In 2008, UMB was canceled because its sponsors favored Long Term Evolution (LTE), a 3GPP project. LTE is the successor to the Global System for Mobile Communications (GSM) network technologies. 3GPP added hand-off support of other technologies to LTE, including CDMA2000 1x and 1xEV-DO. CDMA2000 1x and 1xEV-DO are CDMA technology standards with UMB hand-off support.
These developments have made UMB a redundant technology, while LTE has been established as the universal upgrade path for all wireless networks.