From the course: 4G LTE: Architecture, Protocols, Call Flows, KPIs, Optimization, Performance Analysis

Unlock this course with a free trial

Join today to access over 25,300 courses taught by industry experts.

LTE random access channel (RACH) fundamentals

LTE random access channel (RACH) fundamentals

From the course: 4G LTE: Architecture, Protocols, Call Flows, KPIs, Optimization, Performance Analysis

Start my 1-month free trial Buy for my team

LTE random access channel (RACH) fundamentals

“

Think about trying to shout a message in a crowded noisy room. You wouldn't just start talking. You would raise your hand or say excuse me first to get everyone's attention. Your phone does something very similar to get the network's attention. This initial excuse me is called the random access procedure or RATCH procedure. It is a fundamental part of a network accessibility. The RATCH procedure is your phone's way of raising its hand to ask for a connection. We use RATCH in 3 key situations to first connect to the network which is initial access or to move between cells or for regaining the synchronization. So let's focus on the first part which is the initial access when your phone is turned on. During mobility, there is a handovers comes into picture where again RATCH procedure needs to be performed. And third, in a connected mode, if the timing synchronization is lost and needs to be restored, in that case also RATCH procedure will happen. Now the RATCH isn't just about getting…

Contents