Alcatel -> Huawei swap experience GSM

[forscherau]

I would like to open a discussion or a knowledge database to share experince from an Alcatel -> Huawei swap in GSM
just put in your problems and solutions, e.g. mapping table, ALU features map it to Huawei parameters

working on a 1:1 swap project, but in rural areas drop rate encrease than ALU before, parameter, power etc. are the same

any idea?

[J_Ahmad]

whats the reason, radio drops or Handover drops are incresaing after swap?

Intracell HOs enabled or not?If enabled then check the trend of Intracell Handover drops(CH302C for Huawei) after swap.

[forscherau]

Hi,

there are almost no intracell handover. drop reason is stable state

[grakiter]

modify Radio link time out or call reestablishment

[justdream]

modify Radio link time out or call reestablishment

Dear grakiter, I couldn't open your link
Could you repost in different format/ style?

[forscherau]

Hi some other differences Alcatel to Huawei:
Alacatel has minimum threshold for reducing transmission power of power control BS_TXPWR_MIN (This parameter defines the maximum value of the power attenuation (so the minimum allowed transmission power) relative to the attenuated maximum GMSK output power of the BTS.) Huawei PC works different
Alcatel timing advance handover works different, difference in Alcatel TA must be bigger than TALIMIT, in Huawei can be equal or bigger than TALIMIT, there are several parameter related to TA in Huawei, TA, MAXTA and TALIMIT, TALIMIT should be used for TA handover
Huawei handover algorithm for better cell handover(usually known as power budget handover) has no penalty time!!!, so to avoid ping-pong handover in Huawei you have to play with CONTHOMININTV(Minimum interval between the two consecutive handover decisions of an MS) and Inter-cell hystersis,P/N rule and penalty time/level to avoid Ping-Pong.
Huawei handover are quite sensible of unbalanced handover margins for two cells, e.g. 4dB in one direction, opposite 2dB, leads to ping-pong handover, because of missing penalty timer and drift in traffic(it looks after swap like crossed feeder).
activate RxLevMinCell switch use parameter4 in table GCELLREV set from 65535 to 65023

the algorithm of usage free time slots are very different. the assignment of free time slots with CS and PS traffic differs. for example, in ALU CS traffic uses the free time slots from the 1st trx, first time slots to the last trx last time slots. The PS traffic will be place in the opposite direction, e.g. last time slot, last trx to the first time slot, trx. In Huawei there is no such agorithm, so you can only configure a fixed PDTCH on a trx, where the PS traffic spreads.

Our problem was, that on some trxes an ALU CS traffic was carriered and now it's used for PS. The CS traffic is on further trxes. So if you remember, depends on the quality of the frequency plan, some trxes have good and some poor frequencies. So your drop rate is changing after the swap.

This parameter is misssing in Huawei:
PS_PREF_BCCH_TRX, Indicates whether or not the PS requests shall be preferentially
served with PDCH(s) of the BCCH TRX.

[tudojunto.gl]

Hi,
Recently we are changing siemens to huawei.