[shadow]

can anybody explain in details the 2:1 and 4:1 multiplexing mode in huawei when adding new E1 in the site

[Smart]

they both are multiplexing modes.
they show that you will combine 2 lines in 1 or combine 4 in 1.
for example
if you have SDCCH congestion on abis with 2:1 you can change it to 4:1 and you have just doubled your E1 TS

[enginner]

2:1 or 4:1 is a type of Statistical Multiplexing Mode.
Statistical multiplexing is a technology where n channels share one 64 kbit/s timeslot, each in a different time slice.

For example you use 1:1
For 10 TRX it is necessary on Abis interface:
1OML (64 kbit/s) + 10RSL (64 kbit/s) + 10*8TCH (16 kbit/s ) = 31 timeslots

In other case for 4:1
(1OML (64 kbit/s) + 10RSL (64 kbit/s))/4 + 10*8TCH (16 kbit/s ) =23 timeslots

[NACM-SUN]

2:1 is a half-rate multiplexing mode while
4:1 is a full rate concentrated multiplexing mode.
wherein:
2:1, you can only add an optimum of 13 TRX for every 1 E1;
4:1, you can only add an optimum of 15 TRX for every 1 E1.

Considering you will fill every TRX with 1 SDCCH only.

[Author]

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