TFI identifies a connection for one MS.
the connection can be DL, in this case the MS receives a DL TFI.
Or it could be UL, in this case UL TFI.
Or both, in this case the MS receives a DL TFI and a UL TFI.
Thank you. In the Packet Uplink Assignment message I see both Uplink TFI assignment parameter as well as usf specific timeslot presence indication. What is the difference between them?
Hello, Pawel!
Uplink TFI and USF are assigned to MS for the further using:
– given TFI is contained in every RLC block from that MS;
– given USF is contained in DL RLC blocks from the network to MS, when network is expecting RLC data from MS/
B.R.
TFI is a logical identifier… it is used to distinguish the owner of a block from another MS.
USF is a green light, sent in DL to the MS. Every time the MS gets its own USF in the DL block “header”, it can upload its own data in the next UL block.
USF is just a mechanism to multiplex several UL MS in one UL timeslot. This green light is dynamically distributed among all the UL users. Each block.
Thank you for all responses. My problem was, the theory was not fitting to the parameters names used by tool I am using to collect the log. Now, I understand the problem.
I didn’t really understand your question.
each active user receives its own TFI.
In one TRX of a cell, for example, there is, let’s say, 30 users that are using DL + UL TBF. Each of them have its own TFI for UL and also a TFI in DL. They may or may not be the same. TFI is just the identifier of a TBF.
In another TRX of the cell, there could be, let’s say, 25 users. Each of them would have their own TFI (or couple of TFI, 1 UL, 1 DL).