- This topic has 60 replies, 1 voice, and was last updated 6 years ago by Lemaure.
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5th March 2009 at 07:27 #55936PixGuest
Hello,
1×1 with 9 freq, for a max acceptable load of 12%,
that’s 1 hopping TRX per sector. (12% * 9)
So you can have 2 TRX per sector : the BCCH TRX and a hopping TRX.
5th March 2009 at 07:51 #55937ProGuestThanks pix….
What is maximum capcity i can use for 9 hopping frequecies with differenet MAIO?
Explain with Example
Regards,
Pro7th March 2009 at 21:32 #55938PixGuestPro,
My previous post was already an acceptable answer to your current question… what exactly do you need to know ?
13th March 2009 at 11:17 #55939IrfanGuestPlease “MAIO” STAND FOR ?
And explain it.13th May 2009 at 08:56 #55940MDH???GuestHello Bob.
with 36 hopping Freqs and reuse pattern of 1*3 with 12 TRX each you can have up to 8 TRXs per cell, i.e S888 configuration with MAIO settings as seen below;
Sector 1: 0,2,4,6,8 and 10
Sector 2: 1,3,5,7,9 and 11
Sector 3: 0,2,4,6,8 and 10But challenge with 1*3 reuse pattern is;
1: All your site should be on grid and pattern
2: All your cells should have same azimuth.I would like to recommend to you to use 1*1 reuse pattern for SFH implementation rather than 1*3 to due above constrains.
13th May 2009 at 08:59 #55941MDH???GuestSorry not S888, BUT S777
13th May 2009 at 09:13 #55942MDH???GuestIf you use 1*1, you will have 35 MAIOs.
the RF load will be much small and hence better network quality, RF Load= Kdtx*Hardware Load*(n/N)
where
Kdtx=0.7,Hardware Load=0.9 (Assuming 90% of TCH TS will be busy.
n= number of hopping TRXs per cell
N=number of hopping TRX (MAL list)=36 in you case.Your will vane below MAIO CONFIGURATION.
BCCH 2ND 3rd 4th 5th 6th 7th
Sector 1 X 0 6 12 18 24 30
Sector 2 X 2 8 14 20 26 32
Sector 3 X 4 10 16 22 28 3413th May 2009 at 22:46 #55943Fresh OptGuestHi,
We are experimenting in an isolating area of our network and we use this:
-configuration = 4 x 4 x 4
-SFH
-for BCCHs we use channels 1 to 42
-second TRX : primary GSM, channels=44 to 58
-third and fourth TRX : G1 , channels=975 to 1023
-MAIO:
Cell A: 0, 6, 12
Cell B: 2, 8, 14
Cell C: 4, 10, 16Is this correct? If it is correct, can we reduce the nb of freq. for the second TRX in order to gain more freq. for BCCHs. Is this 1*2 freq. reuse?? And, please, any one give the formula for calculating the freq. load. As I know load%=Nb of hopping TRXs/Nb of freq in MAL. Is it the same formula for 1*3?
Regards,
Fresh Opt14th May 2009 at 21:22 #55944abdrGuestwhat is the function of Franctional loading?
what should be the miinimum value of fractional loading.
I found that in our network, they are using 100% fractional loading (SFH). Is it a poor frequency plan???They have 24 frequencies to use in hopping but they are using fractional loading 100%.Whats your recommendation about this plan?
Which frequency re-use pattern should be best for this?
Thanks.15th May 2009 at 06:32 #55945IRFANGuestHello Bob,
Kindly if you have a knowladge about “MAIO” so explain for me.21st May 2009 at 20:59 #55946abdrGuestHi again repeating.Some 1 pls feedback..
what is the function of Franctional loading?
what should be the miinimum value of fractional loading.
I found that in our network we are using 100% fractional loading (SFH). Is it a poor frequency plan???They have 24 frequencies to use in hopping.
Which frequency re-use pattern should be best for this?25th May 2009 at 21:26 #55947Fresh OptGuestHi again,
any idea about the configuration I described on 13 May. Please!26th May 2009 at 06:24 #55948PixGuestYeah, i’ll try to answer.
Why there are different frequencies for TRX 2 and TRX 3&4 ? Is it really a good choice ?
–> No.Why did you do something like this ?
–> Probably because it is not possible to mix G1 and PGSM frequencies in same TRX ?Are you sure ??? Upgrade your release software and enjoy the benefits of mixed PGSM + G1 hopping list.
–> Ok, will do.Is this 1×1 or 1×3? 1×1 means all cells of same BTS use the SAME frequencies lists. 1×3 means each cell is using only one third of the total band. (each cell has different MA list than it’s co-BTS sisters)
Now, for TRX2, you have 15 frequencies. The radio load is then:
1/15 = 6.7%.
Theoretically, you should be fine as long as load < 12%. So you could use only 8 frequencies. On top of that, i assume the second trx is not 100% busy at busy hour... is it ? If it's only 80% busy, then multiply your load by 0.8. And adjust the nb of frequencies accordingly. For TRX3 and 4: 48 frequencies. 2/48 = 4.1%. Here again, you are way below the std load. Means you are wasting frequencies. HOWEVER, since you need more than 42 BCCH, I'm afraid you have a very poor antenna design, a lot of overlaps, not enough downtilt, too much overshooting, and so on. So forget about the standard thresholds (12% for 1x1, and about 30% for 1x3), and use your own in order to ensure good QoS in each TRX. And really, try to group all G1 and PGSM frequencies 🙂 Life = easier, hopping = more efficient.26th May 2009 at 06:56 #55949Fresh OptGuestThanks Pix million times.
We use different frequencies for TRX2 because of old phones supporting PGSM and for TRX3&TRX4 G1 because of interference of other operaters in PGSM. We thought that’s optimal solution satisfying costumers with old phones and avoid somehow intererence. We use B9, upgrading in B10 can we mix G1+PGSM? You’re right, there is to much overlaps and we are working on it.
Regards,26th May 2009 at 17:55 #55950PixGuestYes, in B10, you can mix. You can’t in B9 ? I thought you could.
Since your BCCH is already PGSM, you don’t need a second TRX with pure PGSM frequencies. The amount of old MS must be very small.
There is an indicator that can give you the ratio of EGSM MS in your network (I’ll give you the name tomorrow… but you can find it in RNO by searching “EGSM” :)) )Just one question : why do you need more than 42 BCCH freq ?? Is your network design really terrible ? The amount of interference is that bad ??
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