Redline Communications Inc. AN100UA 用户手册

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页码 119
 
Red
MAX
 
Base Station
 
User Manual
 
 
 
Doc. #70-00058-01-01 
Proprietary Redline Communications © 2007 
July 13, 2007 
Page 24 of 117
 
silence suppression. This is efficient for applications that have a real-time component and 
continuously changing bandwidth requirements. 
Non-Real-Time Polling Service (nrt-PS) 
The base station schedules regular transmit opportunities for the subscriber to send 
variable size data packets. Typical applications may include high bandwidth FTP. The 
polling period may typically be one second or less, even during periods of network 
congestion.  
Best Effort (BE) 
The base station schedules transmit opportunities for the subscriber to send traffic based 
on unused bandwidth after all higher level traffic scheduling requirements are serviced. 
Typical applications may include Internet access and email. Best effort service flows can 
be assigned a priority of 0 to 7. 
Unsolicited Grant Service (UGS) 
The base station schedules a continuous series of transmit opportunities for the subscriber 
to send fixed size data packets. This schedule supports real-time applications including 
VoIP or TDM transport. The UGS pre-scheduled grants guarantee reserved bandwidth 
and reduce latency introduced by repetitive grant requests. The service flow will not 
transmit packets larger than nominal grant interval. 
Traffic Scheduling Algorithm 
The base station scheduling algorithm uses two scheduling passes. On the first pass, the 
scheduler attempts to allocate bandwidth to meet the minimum rates for all active service 
flows. If there is available bandwidth remaining at the end of the first pass, the scheduler 
executes a second pass and attempts meet all specified maximum rates. During both 
passes, bandwidth allocations are assigned based on the following order of assessment: 
1.  Priority of the scheduling service type, from highest to lowest (rtPS first, and then 
BE). 
2.  Traffic Priority setting when multiple service flows have the same service type. 
Wireless transmission bandwidth is optimized by granting allocations based only on 
traffic available for immediate transmission: only the required bandwidth is allocated, 
and idle service flow channels do not receive any bandwidth allocation.