Ultra Mobile Broadband
UMB (Ultra Mobile Broadband) was the brand name for a project within 3GPP2 to improve the CDMA2000 mobile phone standard for next generation applications and requirements. In November 2008, Qualcomm, UMB's lead sponsor, announced it was ending development of the technology, favoring LTE instead.
Like LTE, the UMB system was to be based upon Internet (TCP/IP) networking technologies running over a next generation radio system, with peak rates of up to 280 Mbit/s. Its designers intended for the system to be more efficient and capable of providing more services than the technologies it was intended to replace. To provide compatibility with the systems it was intended to replace, UMB was to support handoffs with other technologies including existing CDMA2000 1X and 1xEV-DO systems. However 3GPP added this functionality to LTE, allowing LTE to become the single upgrade path for all wireless networks. No carrier had announced plans to adopt UMB, and most CDMA carriers in Australia, USA, Canada, China, Japan and Korea have already announced plans to adopt either WiMAX or LTE as their 4G technology.
Summary
- OFDMA-based air interface
- Frequency Division Duplex
- Scalable bandwidth between 1.25-20 MHz (OFDMA systems are especially well suited for wider bandwidths larger than 5 MHz)
- Supports mixed cell sizes, e.g., macro-cellular, micro-cellular & pico-cellular.
- IP network architecture
- Supports flat, centralized and mixed topologies
- Data speeds over 275 Mbit/s downstream and over 75 Mbit/s upstream
Features
- Significantly higher data rates & reduced latencies using FL advanced antenna techniques
- MIMO, SDMA and Beamforming
- Higher RL sector capacity with quasi-orthogonal reverse link
- Increased cell edge user data rates using adaptive interference management
- Dynamic fractional frequency reuse
- Distributed RL power control based on other cell interference
- Real time services enabled by fast seamless L1/L2 handoffs
- Independent RL & FL handoffs provide better airlink and handoff performance
- Power optimization through use of quick paging and semi-connected state
- Low-overhead signaling using flexible airlink resource management
- Fast access and request using RL CDMA control channels
- New scalable IP architecture supports inter-technology handoffs
- New handoff mechanisms support real-time services throughout the network and across different airlink technologies
- Fast acquisition and efficient multi-carrier operation through use of beacons
- Multi-carrier configuration supports incremental deployment & mix of low-complexity & wideband devices
Fourth-Generation Cellular Technology Benefits
UMB was intended to be a so-called fourth-generation technology. These technologies use a high bandwidth, low latency, underlying TCP/IP network with high level services such as voice built on top. Widespread deployment of 4G networks promises to make applications that were previously not feasible not only possible but ubiquitous. Examples of such applications include mobile high definition video streaming and mobile online gaming.
UMB's use of OFDMA would have eliminated many of the disadvantages of the CDMA technology used by its predecessor, including the "breathing" phenomenon, the difficulty of adding capacity via microcells, and the fixed bandwidth sizes that limit the total bandwidth available to handsets.
External links
- 3GPP2 Standards and specifications
- CDMA Development Group (CDG)