User Manual

! !! !!!!!!!!!!!!!!!!!!!!!!!!! !
!
!
12!
1.2!PRODUCT!OVERVIEW:!WIMAX!TRANSMISSION!FEATURES!
!
The following transmission features are supported by the WiMAX Outdoor CPE to provide stable
and error-free connection.
1.2.1!DYNAMIC!ADAPTATION!
Dynamic adaptation enables the CPE to maintain a high data rate while taking into account current
link conditions like half-loss, interference, and seasonal foliage changes. The CPE monitors wireless
link conditions on a burst-by-burst basis and uses dynamic adaptive modulation control, based on the
measured CINR (Carrier/(Interference + Noise) Ratio), to regulate the link.
1.2.2!ADAPTIVE!CODING!
!
Each data transmission to or from the CPE contains extra, redundant information to reduce the errors
introduced during transmission. A coding rate is the ratio of meaningful data to this extra padding
(including error correction data). Adaptive coding enables the CPE to dynamically change the coding
rate depending on this ratio. This CPE supports coding rates of 1/2, 2/3, and 3/4.
1.2.3!ADAPTIVE!MODULATION!
Adaptive Modulation is used to specify what modulation technique is coded in to carriers composing
orthogonal frequency-division multiplexing (OFDM) symbols. This CPE supports QPSK, 16 QAM,
and 64 QAM modulation techniques.
1.2.4!TRAFFIC!CLASSIFICATION!
Traffic Classification categorizes transmission bursts by searching for pattern matches within the
data. Classifications (for example, burst destination, source MAC address, and Virtual LAN tags) are
defined and managed by the base station and transmitted to the CPE.