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davidbrayan
2008-12-29, 09:35 PM
I tried tuning a model in Asset,
got this as an output,
so can you people verify if its ok or what?
guide me for a better and realistic prediction,also its not smooth.
TX antenna used is omini 11db gain 27m height.
clutter losses and offset values are set by the tool itself while auto tuninig.
i dont know if they are right or wrong.
just stuck into it,help me out

Please send me any good docs about model tuning.

BR
db

justdream
2008-12-29, 11:11 PM
what about your STD and ME?

this is very important and tell me if you are near from actual or not.

Also I would like to know your colors legend and what's your operating frequency?

Good luck

davidbrayan
2008-12-29, 11:38 PM
std 9.5
me 0
color legends are
0 to -65 dark green
-65 to -75 light green
-75 to -85 yellow
-85 to -95 orange
-95 to -102 red
excluded signal below -94 in cw data
operating freq is 1851 MHz

davidbrayan
2008-12-29, 11:39 PM
std around 7.5 to 8 is better but im unable to drag it down to 8
its always above 9

DCA
2008-12-29, 11:55 PM
It could be that your drivetest dat is not accurate enough (to less samples). Also the used clutter and height in Aircom could cause the error. A std dev 7dB with an accurancy of 80% for every clutterclass or more is possible.....

davidbrayan
2008-12-30, 12:17 AM
here are otherdetails if you can look into


It could be that your drivetest dat is not accurate enough (to less samples). Also the used clutter and height in Aircom could cause the error. A std dev 7dB with an accurancy of 80% for every clutterclass or more is possible.....

venom
2008-12-30, 12:47 AM
If your STD is above 9 then it means your model is not well tuned, verify the drive measurements, You should use the Scanned Drive Data with scanning done from an external antenna (preferable).

Model Tuning is always a seperate project and drive test is usually done by transmitting the clean unmodulated frequency. This GIMS Drive Test data is one of the examples for it.

STD should be below 8, the lesser value means your model is more accurate. Above 8 is always considered as the in-accurate model !

Clutter Definitions and weights are defined according to the area at which you have done the drive test or for which you are actually making a model, for example if you are making a model of URBAN AREA then the more/highest weightage should be given to it ! Please also note that the lesser resolution you use, the better model you can make !

Smoothing Effect changes with the rollout factor. But before using smoothing, you must make sure that your model is correct. If it is incorrect, then prediction with smoothing is also very un-reliable !

justdream
2008-12-30, 03:40 AM
Guys,

what do you think about letting ASSET automatically tune the clutters through and offset losses?

is that reliable? what did you do in your past expereince?

davidbrayan
2009-05-26, 04:43 PM
now the problem is,
its not going to tune in any case since the mean error is around -25 to -30.
the approach i used is .
1. converted CW data to signia TX and RX files, for that i exported CW drive data to text with latitude longitude and RSSI, renamed the text file to siteid.dat this is the RX file for signia format, now created a header TX file with details of the site used for CW transmission like latitude,longitude,
height 27m
power(EIRP) 52 i.e. 20W=43dbm,Ga=11dbi,Losses=2dbm, so EIRP=43+11-2=52
Antenna omini, i've the pattern for that.
ground height
tilt
azimuth
with few other details.
created this text file and renamed to .hd
2. now created a fresh project with all data like clutter,heights and vectors.
3. imported the omni antenna.
4. created a standard macrocell3 model with default parameters.
5. created a site with same information as in CW signia .hd file, like same latitude, longitude, height ,EIRP,tilt, model etc.
6. loaded the .hd file,generated pathloss,
now here is the problem ,
if i analyse the CW data , it gives mean error around -25 or -30 and the mmodel is far tuned whatever changes i do.
also if i remove the antenna pattern from signia.hd file then all is well and i can tune the model.
but whatever antenna i use its not going to tune.

Any way out?
somthing missing?
or somebody can help me with this?

BR
db

MINTO
2009-05-26, 05:39 PM
Hi David..i have worked on atoll, in atoll first we will do automatic calibration..then we will run prediction & then we compare it through analysis tool..then check the error in the sample..delete below & above -20&+20 ..then save it & again calibrate the model..finally you have to play with k1 & k2

giegala
2009-05-26, 08:19 PM
Hi Dave,

i could not figure out from your operation list, but have you done binning of measurements (like Actix does).

You should have only one measurement value per prediction bin. Say, the predicion uses 50x50 m grid, then all measurements should be averaged per grid element. This would remove fading effects and give you better std. dev

putrawhisnu
2009-06-10, 03:11 PM
now the problem is,
its not going to tune in any case since the mean error is around -25 to -30.
the approach i used is .
1. converted CW data to signia TX and RX files, for that i exported CW drive data to text with latitude longitude and RSSI, renamed the text file to siteid.dat this is the RX file for signia format, now created a header TX file with details of the site used for CW transmission like latitude,longitude,
height 27m
power(EIRP) 52 i.e. 20W=43dbm,Ga=11dbi,Losses=2dbm, so EIRP=43+11-2=52
Antenna omini, i've the pattern for that.
ground height
tilt
azimuth
with few other details.
created this text file and renamed to .hd
2. now created a fresh project with all data like clutter,heights and vectors.
3. imported the omni antenna.
4. created a standard macrocell3 model with default parameters.
5. created a site with same information as in CW signia .hd file, like same latitude, longitude, height ,EIRP,tilt, model etc.
6. loaded the .hd file,generated pathloss,
now here is the problem ,
if i analyse the CW data , it gives mean error around -25 or -30 and the mmodel is far tuned whatever changes i do.
also if i remove the antenna pattern from signia.hd file then all is well and i can tune the model.
but whatever antenna i use its not going to tune.

Any way out?
somthing missing?
or somebody can help me with this?

BR
db

hi david,
can you attach your file (log)
also the step

i think it would be easier to following your step without have to online everyday :)
at least maybe we can try at our place :)

CMIIW

cheers

nova_debussy
2009-06-11, 01:03 PM
hi D & friends

send me CW logfile, antenna pattern file (for my case .ant file is good), clutter data, Tx power and other para as declaired above

i would like to recheck, for good tunning result Standard variance should be 4.5 to 7.5dB, mean is not strick required

and you should leverage CW measure data before using it to tune your model so that you could get better tunning results

cheers

NV

DCA
2009-06-12, 12:55 AM
Did you split your CW data into LOS and NLOS before tuning?

venom
2009-06-12, 02:07 AM
now the problem is,
its not going to tune in any case since the mean error is around -25 to -30.
the approach i used is .
1. converted CW data to signia TX and RX files, for that i exported CW drive data to text with latitude longitude and RSSI, renamed the text file to siteid.dat this is the RX file for signia format, now created a header TX file with details of the site used for CW transmission like latitude,longitude,
height 27m
power(EIRP) 52 i.e. 20W=43dbm,Ga=11dbi,Losses=2dbm, so EIRP=43+11-2=52
Antenna omini, i've the pattern for that.
ground height
tilt
azimuth
with few other details.
created this text file and renamed to .hd
2. now created a fresh project with all data like clutter,heights and vectors.
3. imported the omni antenna.
4. created a standard macrocell3 model with default parameters.
5. created a site with same information as in CW signia .hd file, like same latitude, longitude, height ,EIRP,tilt, model etc.
6. loaded the .hd file,generated pathloss,
now here is the problem ,
if i analyse the CW data , it gives mean error around -25 or -30 and the mmodel is far tuned whatever changes i do.
also if i remove the antenna pattern from signia.hd file then all is well and i can tune the model.
but whatever antenna i use its not going to tune.

Any way out?
somthing missing?
or somebody can help me with this?

BR
db

Y dont u use ADVANTAGE to convert the TEMS data to signia !!

Your drive is not detailed, you need to have a very very detailed drive in order to tune the model !

The frequency which you are transmitting needs to die out in the drive, this will make ur model accurate, when tuning you need to see the slope plot, the more u r closer to 8, the more points are on the line, your object is to make the maximum points on the slope line !!

changes to values K1 and K2 will also considerably change STD, whereas if u change K3, k4, k5, k6 and k7, it will do the fine tuning !

RF Survey
2009-06-12, 11:11 AM
all brother's

try to check this attachment file, this is .hd and .dat file that i make to model tunning at bali, this is the example, this is the same format to work in ASSET and NETACT,

try....:)

tinyuer
2009-07-08, 01:05 AM
here is asset‘s model tuning document

RF engineer
2009-07-08, 06:27 AM
Hi friends
Most important thing in model tuning is the data come from CW scanning and in the scanning tool it gives you option for binning to perform by time trigger or distance trigger and cluster design .
Normally CW for time triggering is easy to be done but there one draw back that fading is time dependent so it makes your measurement not correct if you don't perform as much as possible for samples normally is 40* wavelength.( normally perform cw test in night time all the road is open and you can some how control the measurement.
and some cluster like rural it is better to be done on distance triggering because you have limit the car speed and performing measurement on each distance .
Attach is aircom model tuning procedure hope helps you.

ISSAYH
2010-04-21, 10:29 PM
It could be that your drivetest dat is not accurate enough (to less samples). Also the used clutter and height in Aircom could cause the error. A std dev 7dB with an accurancy of 80% for every clutterclass or more is possible.....

How can i know the accuracy % of my model?

Br,
ISSA

redendo
2010-04-21, 11:12 PM
thanks for this nice share


Hi friends
Most important thing in model tuning is the data come from CW scanning and in the scanning tool it gives you option for binning to perform by time trigger or distance trigger and cluster design .
Normally CW for time triggering is easy to be done but there one draw back that fading is time dependent so it makes your measurement not correct if you don't perform as much as possible for samples normally is 40* wavelength.( normally perform cw test in night time all the road is open and you can some how control the measurement.
and some cluster like rural it is better to be done on distance triggering because you have limit the car speed and performing measurement on each distance .
Attach is aircom model tuning procedure hope helps you.

mojiiiiii
2010-09-09, 06:21 PM
please upload this docs on rapidshare