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electron
2010-07-27, 01:55 AM
Hi All,


As we have 1/1FLP AND 1/3 FLP can you please let me know which one has more hopping gain and when is better to use?


Thanks

Processor
2010-07-27, 08:20 PM
1/3 has better gain but is used mainly in DCS where u have more channels to play with while 1/1 has less gain and is used more in GSM due to less channels

More questions please............

projtcho2
2010-07-27, 09:15 PM
Hi guys,

1/1 is easier to implement as the 1/3 uniform pattern of the sector azimuths is needed. With 1/1 you don't need exactly matching the azimuths unless in 1/3 is highly recommended.
Cheers,

RF engineer
2010-07-27, 09:42 PM
Hi guys,

1/1 is easier to implement as the 1/3 uniform pattern of the sector azimuths is needed. With 1/1 you don't need exactly matching the azimuths unless in 1/3 is highly recommended.
Cheers,
More to the above comment is also how much bandwidth do you have is it enough to use 1*3 or 1*1 normally 1*3 need more bandwidth than 1*1 .
BR
RF

RFSimanullang
2010-07-27, 09:43 PM
i think 1/3 is better than 1/1 since there is no freq collision between cell at 1 bts.

danikd
2010-07-28, 04:42 AM
Hi All,


As we have 1/1FLP AND 1/3 FLP can you please let me know which one has more hopping gain and when is better to use?


Thanks
If you have an ability to plan frequencies - plan it!!!

Correctly planned frequency allocation always provides better results.

I test it for many networks with different frequency allocation before and after.

I've personally did more than 200 new frequency plans with only one result - planned allocation is always better.

s52d
2010-07-28, 06:58 AM
If you have an ability to plan frequencies - plan it!!!

Correctly planned frequency allocation always provides better results.

I test it for many networks with different frequency allocation before and after.

I've personally did more than 200 new frequency plans with only one results - planned allocation always better.

Yes, indeed.

It all depends on number of ch available.
When I have only 20: 11 to BCCH, 9 to TCH, reuse 1. Forget 4+4+4 there.

When I have 15 MHz ... 1800 of course... do BCCH + 1/3 with three groups of 16.

Inbetween: plan.
1/1 worrks if ratio nr_of_trx/nr_of_ch is low: you just use probability.
1/3 is better, until two same groups are strong neighbors. 1/1 is better there.

But: if you have infomation on interference, if you know how: you can allways add more
information into interference suppression as plain probability.

Uh, I might upload some 10 years old articles about. It is so simple ....


BR
s52d

danikd
2010-07-28, 07:20 AM
Yes, indeed.

It all depends on number of ch available.
When I have only 20: 11 to BCCH, 9 to TCH, reuse 1. Forget 4+4+4 there.

When I have 15 MHz ... 1800 of course... do BCCH + 1/3 with three groups of 16.

Inbetween: plan.
1/1 worrks if ratio nr_of_trx/nr_of_ch is low: you just use probability.
1/3 is better, until two same groups are strong neighbors. 1/1 is better there.

But: if you have infomation on interference, if you know how: you can allways add more
information into interference suppression as plain probability.

Uh, I might upload some 10 years old articles about. It is so simple ....


BR
s52d
Even with only few frequencies available - the planned well frequency allocation performing better - tested in the field many times.
I do agree on that the fixed allocation 1/3 or 1/1 makes easier daily live - not necessary to touch frequencies for new TRXs. But this can be misleading!!!! Good frequency plan is an advantage of GSM over CDMA-like technologies. Good frequency plan may hide some mistakes that are coming from bad cell plan.
The ability hide is YES related to number of frequencies that you have, but anyway do not forget about cell plan. Accuracy of cell plan should match your frequency band availability. Smaller frequency band - better cell plan required.