Our extensive experience in developing WiMAX solutions has granted us unparalleled expertise in OFDMA technologies that enable converged voice, video and multimedia services over an all-IP network architecture, to address the current and future needs of the communications, business and entertainment markets.
Orthogonal Frequency Division Multiple Access (OFDMA) is a cellular air interface used in 4G communications networks such as WiMAX and LTE, based on OFDM for multiple, simultaneous users. OFDMA has several benefits ranging from increased flexibility to improved throughput and robustness. By assigning subchannels to specific subscribers, transmissions from several subscribers can occur simultaneously without interfering, thus minimizing an effect known as Multiple Access Interference (MAI). Furthermore, subchannelization enables the concentration of transmit power over a reduced number of subcarriers. This results in increased link margins which in turn, lead to improved range and coverage.
The IEEE 802.16e-2005 amendment was developed to extend the 802.16 Air Interface Standard to cover mobile applications. This amendment adopted OFDMA to provide the flexibility to deal with various usage scenarios and the challenges associated with rapidly moving mobile users in a NLOS environment. The 802.16e-2005 standard provides three subchannel allocation alternatives that can be selected based on the usage scenario, as follows:
- Subcarriers can be scattered throughout the frequency channel range; this is referred to as fully used sub-channelization or FUSC
- Several scattered clusters of subcarriers can be used to form a subchannel; this is referred to as partially used sub-channelization or PUSC
- Subchannels can be composed of contiguous groups of subcarriers; this is referred to as adaptive modulation and coding or AMC
BreezeMAX® leverages Alvarion's market-leading expertise in technologies such as OFDMA to enable converged voice, video and multimedia services over an all-IP network architecture, addressing the current and future needs of the communications, business and entertainment markets. The foundation of Alvarion’s best-of-breed, end-to-end 4Motion® Mobile WiMAX™ solution, BreezeMAX offers operators greater coverage, capacity and throughput for the provision of top quality multi-play services with enhanced end user experience.
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