when periodicPHR-Timer, prohibitPHR-Timer will get start and expire? What is dl-PathlossChange?

Question

After expiry is it mandatory to send BSR in next SF or can it be delayed for some reason ?

Answer 1

HI,

Based on Reference Signals strength UE calculates the pathloss. dl-PathlossChange is the threshold parameter, upto this value pathloss can be acceptable. If pathloss value changes beyond this value UE sends PHR to the network.

periodicPHR-Timer is configurable parameter as per vendor. lets suppose SF100 configured, UE have to send PHR once in every 100 subframes.

prohibitPHR-Timer is also configurable parameter, which denotes when this timer running UE should not send PHR.

Comments

Based on which reference signal path-loss is calculated? Is PHR is sent on Transport-Block? If so, in which slot or subframe it is sent?

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PHR is sent through ULSCH channel , whenever UE has UL grant it will send as part of UL TB.
based power notified by network and the measured RS power at UE antenna port UE will calculate pathloss.

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PHR is the mac control element ... obviously its part of MAC PDU . All control elements resides first in the formation of the TB.

Am not sure which RS uses for path-loss .. will update you soon

Answer 2

Hi,

Whenever UE gets UL grant , then UE will start or restart the PHRperiodic timer and Prohibit TImer.

Dlpathloss change is a thrshhold value ,If current pathloss is greater than the dlpathlosschange then UE will trigger a PHR report.

Comments

please explain more on it. I thought that it will start when the UE will send the TB with PHR in it.

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When UE recieve first UL grant after PHR configuration,then UE will start the timer.

Then whenever it expires it will trigger PHR and restart the timer.

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When the timer expires you will send PHR in case of both PHRperiodic and PHRprohibit. It means untill the timer expires you are not going to send the PHR.
PHRprohibit is defined as:Timer which the UE should maintain between sending 2 consecutive PHRs. Therefore why you need PHRprohibit timer when PHRperiodic alone can do the PHRprohibit timer job.