# Need help to measure axial ratio bandwidth in HFSS11

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#### vishalbharate

##### Newbie level 5
I m working on broadband microstrip patch antenna n wants to calculate the axial ratio bandwidth. i hav simulated my antenna design using HFSS11 n found the results. but in results to find axial ratio its giving plot w.r. to theta.if i select a frequency it shows only solution frequecy. in order to calculate AR BW i need plot of AR Vs Frq. So plz help me in this regard. Also how to see thw antenna efficiency in HFSS11?

#### tallface65

##### Full Member level 6
If you want to see AR vs Frequency, you will have to solve either a discrete or Fast frequency sweep to get the spectral field data. If you wish to see antenna efficiency, after solving, go to HFSS -> Radiation -> Compute Antenna/Max Params... This will bring up most antenna data of interest including efficiency. You can also directly plot this through the Reporter.

jyoti07610204

### jyoti07610204

points: 2

#### vishalbharate

##### Newbie level 5
still i hav not got how to see AR vs Freq

#### maisallam

##### Newbie level 3
Well, in order to plot the axial ratio. You need to use the frequency sweep of type "discrete" or "fast sweep" and then click on "Save fields" because the interpolating doesn't allow you to save fields. Then run the simualtions normally. After that from results=> create far field report ==> Rectangular plot (for example) = > click on "Axial ratio" ==> choose the primary sweep to be "frequency" and specify the phi and theta that you wish to plot the axial ratio at.

I hope this helps

points: 2

points: 2

### Koglu

points: 2

#### vishalbharate

##### Newbie level 5
thx for replay but i need to calculate axial ratio bw. so by using above procedure it gives value of AR at that freq only.

#### ferdows

for calculation of AR first u should go to far filed radiation and put on sweep calculation then change the X parameter (theta) to frequency and then change the theta and phi from all to u radiation angle and then run simulation
notice that u dont need to calculation of AR ratio that usually linear in uwb antenna

#### vishalbharate

##### Newbie level 5
Hi
but i m working on broadband microstrip antenna n hav bw about 30% so i need to calculate AR BW. n for that purpose i need to hav plot of freq vs AR.

#### ferdows

hi
use the method i say in my last reply to find u antenna AR
if u can not apply that method upload u antenna for me to i check for AR

ferdows

##### Newbie level 5
hello,please upload your file and then i reply you the B.W of axial.ratio.axial ratio is essential parameter in CP and this is rarely difficult in which tetha or phi is minimum

#### saeedafra

##### Newbie level 1
the post is really out of date. But here's a solution. choose discrete frequency sweep instead of the fast mode. Then choose save fields for all frequencies. it gets really time-consuming!! so choose the minimum number of point you need. You may first try a fast sweep to check VSWR BW and then a discrete sweep the frequency range of VSWR BW for a few point.

Then you need to create a report for far field. Choose the appropriate value for theta and phi(usually broadside direction) and choose all values of frequency. in the X sweep tab deselect primary swwp and choose freq instead.

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#### ursamitnaik

##### Newbie level 2
hiii
Its Easy in HFSS 11 . GO in results plot axial ratio (db) plot. Now double click in results on axial ratio plot. now in that box change solution set up from Last adaptive to sweep1. then change X co-ordinate to frequency.(You can see all frequency range in ALL). now u can click apply trace/ new report. It starts simulating. this simulation consumes take few minutes. as it is plotting for all theta ( u already have added in solution set up with step size).
If you want u can plot for theta=0 & 90 . as they are only useful. Go in families tab after double clicking in results on axial ratio plot. click on all(...), press CTRL and chose angles.

points: 2

points: 2

### rajarani

points: 2

#### vishalbharate

##### Newbie level 5
hey thx dude its workinf thx for replay

#### ursamitnaik

##### Newbie level 2
choose theta & phi as Zero deg...
it will give appropriate results

sonia raj

points: 2