Understanding Idle Mode in LTE Network

 Understanding Idle Mode in LTE Network 

Cell Re-Selection

📡 Optimizing LTE Cell Re-selection for Enhanced Network Performance
In LTE networks, efficient cell re-selection mechanisms are crucial for seamless handovers and improved user experience. Let's break down the process

⛔ Intra-frequency Neighbor Cell Re-selection:[ Same Freq + Same Band + Same Priority ]

🔍 Measurement: we have two options :
1- UE continuously measures signal strength.
2- measurements are triggered when 𝑆𝑟𝑥𝑙𝑒𝑣≤𝑆𝑖𝑛𝑡𝑟𝑎𝑠𝑒𝑎𝑟𝑐ℎ
to conserve resources.

📊 Ranking:
-Serving Cell (𝑆): 𝑅(𝑆)=𝑄𝑚𝑒𝑎𝑠(𝑆)+𝑄ℎ𝑦𝑠𝑡
-Neighbor Cell (𝑁): 𝑅(𝑁)=𝑄𝑚𝑒𝑎𝑠(𝑁)+𝑄ℎ𝑦𝑠𝑡
-Decision: Switch to 𝑁 if 𝑅(𝑆)<𝑅(𝑁).

⛔Inter-frequency and Inter-RAT Neighbor Cell Re-selection: [ Diffe Freq + Diffe Band + Diffe Priority ]

🔍 Measurement:
-Higher Priority: Always measure, switch to 𝑁 if 𝑆𝑟𝑥𝑙𝑒𝑣(𝑁)>Thresh𝑋ℎ𝑖𝑔ℎ '' UE moves From Higher Priority to Lower Priority ''
-Lower Priority: Measure when 𝑆𝑟𝑥𝑙𝑒𝑣(𝑆)≤𝑆𝑛𝑜𝑛𝑖𝑛𝑡𝑟𝑎𝑠𝑒𝑎𝑟𝑐ℎ ''UE moves From Lower Priority to higher Priority ''

⚖️ Conditions for Lower Priority: ''UE moves From Lower Priority to higher Priority ''
-Serving Cell (𝑆): 𝑆𝑟𝑥𝑙𝑒𝑣(𝑆)<𝑆𝑠𝑒𝑟𝑣𝑖𝑛𝑔_𝑙𝑜𝑤
-​Neighbor Cell (𝑁): 𝑆𝑟𝑥𝑙𝑒𝑣(𝑁)<Thresh𝑋𝑙𝑜𝑤

​In essence, these algorithms ensure optimal cell re-selection, promoting network efficiency and seamless connectivity for LTE users.
Note : Picture below
-Priority5, for band 900 mhz
-Priority6, for band 1800 mhz
-Priority7, for band 2300 mhz