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October 2012
under General

Teacher Jens Zander created page 17 July 2012

commented 29 September 2012

In exercise 12, we have a reuse factor of 9. This means that km or lm can be equal to 0?

Teacher commented 29 September 2012

Yes.

Also note that in question 12, "reuse 3" means that there are 3 cells in one cluster, "reuse 3/9" means there are 3 sites, 9 cells in one cluster. So, remember to use three sectors per site in the latter case.

commented 29 September 2012

I have one problem with exercise 12 because when I set kn=4 ,ln=1 i get  NaN  as result in sta.iul  and  sta.sirul; morover this appears to be also the median (sta.sirul) and therefore plotting median of Sir to answer the question about the number of cluster we need to use then i have gap (no value)  for the combination (4,1) so 21cluster .....how is possible??? thanks for the reply

Teacher commented 30 September 2012

I don't know which parameters you used for cluster size, sps, offered traffic, etc, but my guess is that you are using a high reuse factor and high load value. Therefore some users in a cell cannot be assigned a channel because all channels in that cell were already in use. In that case this user will not be admitted to the system, so its interference and SINR values will be NaN. When you calculate the median of an array which includes NaN values, Matlab returns NaN. These NaN values cannot be plotted, therefore you see gaps in your plot. So, when you calculate the interference and SINR values, do not include the users which are not admitted to the system. See the help for "isfinite" function.

commented 30 September 2012

to be brief this what my par contains at the begining: (the only diffrence is for that case Kn= 4 and ln =1)

par =

frametime: 1
nframes: 1
slottime: 0.12500000000000
nslots: 8
seed: 1
km: 1
lm: 1
kn: 1
ln: 1
sps: 1
gainconst: -28
noise: -128
alpha: 4
sigma: 0
raa: 0.50000000000000
corrdist: 110
offtraf: 10
mht: Inf
amean: 0.20000000000000
vmean: 1
homargin: 3
pinit: 33
pmax: 33
rbermax: 1
usefastf: 0
kpc: 20
usefh: 0

One user removed his/her comment
commented 30 September 2012

In exercise 14, we have to make a suitable choice of number of clusters. This number should be the one we found in exercise 12? If not, what is the criteria to choose that number?

Teacher commented 30 September 2012

Yes, you should use the result you obtained in exercise 12. If you think that your answer to ex. 12 may be problematic for some reason, use a slightly larger number than what you obtained in ex.12 so that you do not underestimate the effect of interference.

commented 30 September 2012

Also in exercise 15 we have to use the same cluster number?

Teacher commented 30 September 2012

Yes. When you run simulations in ex. 13, 14, 15 you need to use your result from ex.12.

commented 1 October 2012

In question 15, in order to plot SIR, should we use cdfplot or cdfplotmed?

Teacher commented 1 October 2012

Cdfplot and cdfplotmed do almost the same job. The difference is that cdfplotmed can handle matrix input and plots all colums as separate data series. Depending on how your input data is structured, you could use both functions.

September 2012
Page Labs
under General

Teacher Jens Zander created page 17 July 2012

commented 9 September 2012

Hello!

I´m looking for someone to do the labs with. So anyone that does not have a labpartner yet please contact me at:  emasve@kth.se

/ Emanuel

July 2012
under General

Teacher Jens Zander created page 17 July 2012

under General

Teacher Jens Zander created page 17 July 2012

under General

Teacher Jens Zander created page 17 July 2012

Teacher Jens Zander changed the permissions 17 July 2012

Kan därmed läsas av alla och ändras av lärare.

August 2011
under General

Jens Zander created page 26 August 2011