Method and Apparatus for performing outer link loop adaptation (OLLA) as multi-armed bandit (MAB)

Technology: Performing outer link loop adaptation

Industry/Applications:Computer Technology, Wireless Communication, Computer Software, SMEs, Large Enterprises, Retail, BFSI etc.

Market: The global machine learning market is projected to grow at a CAGR of 34.8% during 2023-2030.

It is noted that a rate adaptation metric reflects the channel capacity is computed at the User Equipment (UE), is quantized and fed back to the evolved Node B (eNB).
Long Term Evolution (LTE) supports 4bit quantization wherein the quantized feedback (Channel Quality Indicator (CQI)) is a number between 0 and 15. And Said 4bit CQI value (Cu) is then mapped to a 5bit Modulation & Coding Scheme (MCS) (Mu), at the eNB, wherein the MCS index may not be accurate if the CQI received from the UE is erroneous including other issues related to quality of service, performing OLLA & etc.
Hence, there is a need to address the issues.

The present invention describes a method and an apparatus for performing outer link loop adaptation (OLLA) as a Multi-Armed Bandit (MAB).
Said method comprises:
In First step explains about the associating each of the predefined Modulation and Coding Scheme (MCS) indices to each of the arms of a Multi-Arm Bandit (MAB).
The following step describes about the determining a predefined MCS index to meet a predefined target Block Error Rate (BLER), wherein the predefined MCS index is determined based on a rate feedback value, and an offset value associated with each of the arms of the MAB.
Yet Further step explains about the selecting a first arm of the MAB associated with the determined predefined MCS index.
Still next step describes about the determining whether the BLER, based on a cumulative Acknowledgement/ Negative Acknowledgement (ACK/NACK) response from a User Equipment (UE) for a Transport Block (TB).
The apparatus also performs a few operations comprises of:

selecting a second arm of the MAB, associated with an increased offset value in comparison with the offset value associated with the first arm, in response to determining that the BLER meets the predefined target BLER.
selecting a third arm of the MAB in response to determining that the BLER fails to meet the predefined target BLER.

Technical Perspective:

Associate each of the predefined Modulation and Coding Scheme (MCS) indices to each of the arms of a MAB.
Determine a predefined MCS index, which is a combination of CQI value and an offset, to meet a predefined target Block Error Rate (BLER).
Select an arm of the MAB associated with the determined predefined MCS index to meet the predefined target BLER.
Select the arm of the MAB based on a binary search mechanism, in which the MCS index is used as a search metric in the binary search mechanism.
In the proposed method, different offset values constitute arms of the MAB.
Offset values are used to adjust the MCS index for achieving a certain target BLER.

Industrial Perspective:

Prof. Sheetal Kalyani

Department of Electrical Engineering

TRL-2/3

Proof of Concept ready

Technology Transfer