Hi Huawei team,
using nastar I can see the distribution of TP for a cell, or using CHR I can check the TP when call drop occurs.
So a high TP does it always mean that the UE is far from the nodeB ? Does it always reflect a coverage problem ?
thkss
Hi Huawei team,
using nastar I can see the distribution of TP for a cell, or using CHR I can check the TP when call drop occurs.
So a high TP does it always mean that the UE is far from the nodeB ? Does it always reflect a coverage problem ?
thkss
Hi Fahmi,
can you please show/explain me from where u see in CHR nastar TP before drop occured.
not always drop due to coverage/TP, higher TP it's mean distance from NodeB is more longer is true (like Timing Advance on 2G). We must setting properly with other neighbour on surrounding and seing with SHO Overhead to make sure sharing of coverage (30-40% value of SHO Overhead Threshold)
not always drop due to coverage/TP, higher TP it's mean distance from NodeB is more longer is true (like Timing Advance on 2G). We must setting properly with other neighbour on surrounding and seing with SHO Overhead to make sure sharing of coverage (30-40% value of SHO Overhead Threshold)
thank you,
please could you explain to me in more details what is it sho overhead ? and how to correlate with coverage problem ??
Definition Propagation delay is defined as one-way propagation delay as measured during PRACH access:
Propagation delay = (TRX – TTX – 2560)/2, where:
TTX = The time of AICH access slot (n-2-AICH transmission timing), where 0£(n-2-AICH
Transmission Timing)£14 and AICH_Transmission_Timing can have values 0 or 1.
TRX = The time of reception of the beginning (the first significant path) of the PRACH message
from the UE at PRACH access slot n.
Note: The definition of "first significant path" needs further elaboration.
Range/mapping The Propagation delay is given with the resolution of 3 chips with the range [0, …, 765] chips.
The Propagation delay shall be reported in the unit PROP_DELAY where:
PROP_DELAY_000: 0 chip £ Propagation delay < 3 chip
PROP_DELAY_001: 3 chip £ Propagation delay < 6 chip
PROP_DELAY_002: 6 chip £ Propagation delay < 9 chip
...
PROP_DELAY_252: 756 chip £ Propagation delay < 759 chip
PROP_DELAY_253: 759 chip £ Propagation delay < 762 chip
PROP_DELAY_254: 762 chip £ Propagation delay < 765 chip
PROP_DELAY_255: 765 chip £ Propagation dela
Initial synchronization of a phone requires even more care. Before a mobile transmits there is no way to actually know the offset required. For this reason, an entire time slot has to be dedicated to mobiles attempting to contact the network (known as the RACH in GSM). The mobile attempts to broadcast at the beginning of the time slot, as received from the network. If the mobile is located next to the base station, there will be no time delay and this will succeed. If, however, the mobile phone is at just less than 35 km from the base station, the time delay will mean the mobile's broadcast arrives at the very end of the time slot. In that case, the mobile will be instructed to broadcast its messages starting nearly a whole time slot earlier than would be expected otherwise. Finally, if the mobile is beyond the 35 km cell range in GSM, then the RACH will arrive in a neighbouring time slot and be ignored. It is this feature, rather than limitations of power, that limits the range of a GSM cell to 35 km when no special extension techniques are used. By changing the synchronization between the uplink and downlink at the base station, however, this limitation can be overcome.
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