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LTE Uplink/Downlink Scheduling Algorithm Input and Output?

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What are all the Input and Output of a Simple LTE Mac Scheduler(Round Robin/Best CQI)?

posted Oct 25, 2014 by Selvakumar

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1 Answer

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Not sure what is the question, but let me explain what I know. Please comment if looking for something different.

In LTE Scheduling is defined as allocating pre-determined number of sub-carriers for a fixed time to each
requesting UEs. There are various methods of scheduling, such as channel dependent or channel aware
scheduling methods and channel unaware scheduling. Uplink supports the SC-FDMA whereas downlink supports the OFDMA technology. Since Uplink supports the SC-FDMA technique as its access technology, each users need to be allocated a contiguous resource blocks (RBs).

Uplink scheduling determines which UEs is allowed to transmit and with which resource blocks during a given time interval. However, unlike downlink scheduling, uplink scheduling cannot automatically know the transmission demand from a UE. Thus, before the UE can transmit data to the eNodeB, it first sends a Scheduling Request (SR) to request the transmission permit. When the scheduler in the eNodeB receives the SR, it replies with a scheduling grant for the request. In addition, the scheduler determines the time/frequency resource which the UE should use as well as transport format. After the UE has received the information of assignment, it can transmit data with required parameters over a sub-frame when the grant is valid. In this, LTE uplink scheduler module will be designed to handle both real and non real time data supporting both TDD and FDD frame structure for improving performance.

For more detail please go thorugh the http://www.ijceronline.com/papers/Vol3_issue4/part.3/J**********.pdf

answer Oct 26, 2014 by Salil Agrawal
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