LTE Layer management Strategy and basic working [LMS] Unlock

LMS Insight

Layer Management Parameter Optimization is important aspect & it is triggered when all possible optimization techniques for ensuring best experience to customers is exhausted in the current layer

For Example in a typical 3 Layered cellular network, we have LTE layer (with a mix of TDD(2.5GHz) and FDD(1.8GHz)), followed by WDCMA Layer (WCDMA2100) & then the GSM layer (1800 MHz

Before actually working on Layer Management Parameter Optimization, we need to ensure Traffic Balancing within the layers is proper & as per recommendations to give desired customer experience

Pre-requisite Actions

Ensure below checks before moving to optimize the Layer Management Thresholds for a cell.

Traffic balancing within layers should be optimal - if network has 2 layers of LTE i.e. both TDD-20 MHz & FDD-5 MHz, Traffic distribution for collocated cells with TDD/FDD should be 75:25 (TDD: FDD) or better. This is applicable to networks with 2 carriers of WCDMA as well where the traffic distribution should be close to 50:50 (C1: C2) between 2 layers of WCDMA.

In case of 2 layers of LTE, TDD-20 MHz and FDD-10 MHz, the traffic balancing between the layers should be in proportion with TDD-60 % and FDD-40 %.

In case of 2 Layers for TDD LTE (20 MHz & 10 MHz) and FDD-5 MHz, the traffic balancing between the layers should be in proportion with TDD (20 MHz)-55 % & TDD (10 MHz)-27 % and FDD-18 %.

In case of 2 Layers for TDD LTE (20 MHz & 10 MHz) and FDD-10 MHz, the traffic balancing between the layers should be in proportion with TDD (20 MHz)-46 % & TDD (10 MHz)-23 % and FDD-31 %.

Traffic balancing mechanisms are broadly classified under

Coverage Based

Idle Mode Behavior - Reselection

Connected Mode Behavior – Handover e.g PSHO SRVCC

Load Based

Inter Frequency Load Sharing (IFLS) Data Voice

Service based

CS Fall Back – Speech Calls

Redirection after CSFB

Idle Mode Layer Management