What is open loop and closed loop in LTE?

In Open Loop Control, UE determines its Transmission Power by its own Power Setting Algorithm. It means UE Transmission Power is controled by some feedback input from eNB. In this way, overall power control process form a loop (closed loop). That’s why it is called Closed Loop Control.

What is power control LTE?

The LTE power control mechanism constitutes of a closed loop component operating around an open loop point of operation. Specifically, the open loop component has a parameterized fractional path loss compensation factor, enabling a trade-off between cell edge bitrate and cell capacity.

What is close loop power control?

Closed Loop Power Control (CLPC) Measurement Description. Closed Loop Power Control (CLPC) measurement, as defined in TS 34.122 Section 5.4. 1.4, is used to test the ability of the UE transmitter to adjust its output power in accordance with one or more TPC commands received in the downlink.

What is the main reason for open loop power control?

Open Loop Power Control is an important technique providing adaptation of user transmit power. There are multiple factors like cell size, interference conditions, etc. that determine the optimal settings of power control (PC) parameters.

What is open loop power control?

Open Loop Power Control Measurement Description 1.3, the open loop power control is the ability of the UE transmitter to sets its output power to a specific value. The open loop power control measurement can only be initiated when the Operating Mode is Active Cell and the call status is Idle.

What is power headroom LTE?

Power headroom indicates how much transmission power left for a UE to use in addition to the power being used by current transmission. PHR is a type of MAC CE(MAC Control Element) that report the headroom between the current UE Tx power (estimated power) and the nominal power.

Does power control used in LTE DL Pdsch?

Downlink Rate Control (Power Control) In case of 4G LTE Downlink , rather than varying power in the Downlink, full power is distributed uniformly over the whole bandwidth. The same Power Spectral Density (PSD) is used on all DL channels. For example, PDSCH, PHICH, PDCCH etc.

Is there power control in LTE?

What is difference between open loop and closed loop control system?

The main difference between an open-loop system and a closed-loop system is that the closed-loop system has the ability to self-correct while the open-loop system doesn’t. Consequently, closed-loop systems are often called feedback control systems while open-loop systems are also known as non-feedback controls.

Is open loop better than closed loop?

Difference between Open Loop and Closed Loop Control System