RLT - Radio Link Timeout

RLT - Radio Link Timeout

When SACCH is not decoded this counter is decreased by 1 when it is reaches to zero it result normal call drop. In this period if SACCH is decoded counter is increased by 2.

›       This parameter indicate how much time call maintained when radio environments is bed.

›       If RLT value is high then call is sustain longer time. it is affected to customer  customers perception.

›       Highway and in building cells have higher value of RLT parameter and it is give better improvement of call drops.

›       This parameter is define in AMRFR & AMRHR and  also Non AMRFR & Non AMRHR

›       We can also check this on TEMS radio parameter window

one time slot lasts 0.577ms, Bursts period is 4.615ms

1 SACCH Period= 4.615X104 bursts    (4x26=104 bursts)  = 480ms

Now Radio Link Time Counter:-

 It is depend on SACCH blocks.

This parameter defines the maximum value of the radio link counter expressed in SACCH blocks. Range of 4 – 64 in step size of 4.

Value of RLT. Normally 16, 20, 24. 

If RLT value is 16 then call is sustain around- 7.6 Sec( 16 *480ms) when SACCH will not decoded

If RLT value is 20 then call is sustain around -9.6 Sec( 20*480ms)

If RLT value is 24 then call is sustain around -11.5 Sec( 24*480ms)

RLT Measure in TEMS Radio Parameters

RL Timeout Counter (Cur) : This parameter define the maximum value of the radio link counter expressed in SACCH blocks. Range of 4 – 64 in step size of 4. it shows current value of RLT. Decrease by 1 but increase by 2. When it reaches zero it results in normal DROP Call.

RL Timeout Counter (MAX) : This parameter define the maximum value of the radio link counter expressed in SACCH blocks. Range of 4 – 64 in step size of 4. it shows current value of RLT. Normally 16, 20, 24.