To Shout or Not to Shout: Performance of Power Ramping during Random Access in LTE/LTE-A

Power ramping is one of the mechanisms proposed to help alleviate congestion during random access in LTE cells. We evaluate its performance taking into account preamble SINR considerations as well as Physical Downlink Control Channel (PDCCH) deficiency. Our results show that power ramping can speed up access at small to moderate loads, but that it is actually detrimental at moderate to high loads, with the ability to cause abrupt onset of saturation.