𝗪𝗵𝗮𝘁 𝗶𝘀 𝘁𝗵𝗲 𝗽𝗿𝗶𝗺𝗮𝗿𝘆 𝗳𝘂𝗻𝗰𝘁𝗶𝗼𝗻 𝗼𝗳 𝗣𝗗𝗖𝗖𝗛 𝗶𝗻 𝟱𝗚 ❓

𝗪𝗵𝗮𝘁 𝗶𝘀 𝘁𝗵𝗲 𝗽𝗿𝗶𝗺𝗮𝗿𝘆 𝗳𝘂𝗻𝗰𝘁𝗶𝗼𝗻 𝗼𝗳 𝗣𝗗𝗖𝗖𝗛 𝗶𝗻 𝟱𝗚 ❓

✔ Before going into details, You just need to understand that PDCCH is the heart of the Air-interface as it is being used to allocate and inform the UE about all the Scheduling information needed to start using any service.

✔In addition to this, Proper optimization of the PDCCH resources is one of the most vital parts of either 4G or 5G, As PDCCH 𝗰𝗼𝗻𝗴𝗲𝘀𝘁𝗶𝗼𝗻, 𝗯𝗹𝗼𝗰𝗸𝗶𝗻𝗴, 𝗼𝗿 𝗰𝗼𝘃𝗲𝗿𝗮𝗴𝗲/𝗾𝘂𝗮𝗹𝗶𝘁𝘆 𝗶𝘀𝘀𝘂𝗲𝘀(𝗛𝗶𝗴𝗵 𝗕𝗟𝗘𝗥) can have a severe impact on services such as 𝗩𝗼𝗹𝘁𝗲/𝗩𝗼𝗡𝗥 𝗖𝗮𝗹𝗹𝘀 𝗮𝗻𝗱 𝗟𝗮𝘁𝗲𝗻𝗰𝘆(Ex: Users will wait longer in the queue waiting for the scheduling information in case of congestion or Load imbalance between existing carriers in your network)

✔ 5G PDCCH is mainly used 𝘁𝗼 𝘁𝗿𝗮𝗻𝘀𝗳𝗲𝗿 𝗗𝗼𝘄𝗻𝗹𝗶𝗻𝗸 𝗰𝗼𝗻𝘁𝗿𝗼𝗹 𝗶𝗻𝗳𝗼𝗿𝗺𝗮𝘁𝗶𝗼𝗻 (𝗗𝗖𝗜), which is the same function is 4G. Where it includes Downlink grants, Uplink grants & Transmit power Control commands.

✔ DCI provides the UE 𝘄𝗶𝘁𝗵 𝘁𝗵𝗲 𝗻𝗲𝗰𝗲𝘀𝘀𝗮𝗿𝘆 𝗦𝗰𝗵𝗲𝗱𝘂𝗹𝗶𝗻𝗴 𝗶𝗻𝗳𝗼𝗿𝗺𝗮𝘁𝗶𝗼𝗻, such as DL/UL resource allocation and UE Common group signaling.

✔ DCI provides resource allocation information for applications such as 𝗦𝗜𝗕𝟭, 𝗠𝗦𝗚𝟮/𝟯/𝟰, 𝗣𝗮𝗴𝗶𝗻𝗴, 𝗮𝗻𝗱 𝗨𝗘 𝗗𝗮𝘁𝗮 𝗧𝗿𝗮𝗻𝘀𝗳𝗲𝗿.

📚 Simply, Resource allocation information means to inform the 𝗨𝘀𝗲𝗿 𝗮𝗯𝗼𝘂𝘁 𝘁𝗵𝗲 𝗦𝗲𝘁 𝗼𝗳 𝗙𝗿𝗲𝗾𝘂𝗲𝗻𝗰𝘆 𝗿𝗲𝘀𝗼𝘂𝗿𝗰𝗲𝘀 𝗻𝗲𝗲𝗱𝗲𝗱, such as the 𝗻𝘂𝗺𝗯𝗲𝗿 𝗼𝗳 𝗿𝗲𝘀𝗼𝘂𝗿𝗰𝗲 𝗯𝗹𝗼𝗰𝗸𝘀 required and the location of these RBs in the frequency and time domain; in addition to this, it also informs the User about the 𝗠𝗖𝗦 𝗧𝗮𝗯𝗹𝗲 (𝟲𝟰𝗤𝗔𝗠 𝗼𝗿 𝟮𝟱𝟲𝗤𝗔𝗠) to be used and other information 𝗮𝗯𝗼𝘂𝘁 𝗛𝗔𝗥𝗤 𝗳𝗲𝗲𝗱𝗯𝗮𝗰𝗸. (Examples added in below figure for visual understanding)


𝗗𝗮𝘁𝗮 𝗦𝗼𝘂𝗿𝗰𝗲:
- 5G NR in Bullets
- 5G Next generation wireless access technology

Refer to below youtube video for more details