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pTroll
2012-03-05, 12:18 AM
Hello,


Can anybody share their knowlege about portable test transmitters which could be connected to indoor antenna to simulate coverage in indoor environment.


One thing is to calculate required EIRP from the antenna which is based on link budget, the other thing is to make sure that there will be no dead spots of coverage indoors (Walls, floors, reflections, scattering... a lot of things to keep in mind) - none prediction tool/speradsheet is 100% accurate.


I know that "Tems transmitter" is quite popular, but it is not supported by ASCOM any more.
Transmitter should have output power from -10 dBm to about +25 dBm. It should be portable without need of external power supply. Great thing would be if I could program BCCH channel, so that RSSI could be mesured with Tems Pocket for post processing.


Maybe someone has experience of using theese CW generators? http://www.ptsyst.com/FSG-B.pdf


I have been dealing with analog repeaters deployment (with composite output power up to 18 dBm), but there are some bigger projects coming with dedicated BTS/NodeB and I'm a bit worried - don't want to make expensive mistakes.

pTroll
2012-03-06, 10:16 PM
Anybody?
Someone of You should have some experiene with test antennas...?

Rotorhead
2012-03-12, 05:32 PM
There are many CW transmitters available, a google search throws up the following:

http://www.google.co.uk/#hl=en&sclient=psy-ab&q=cw+transmitter&oq=cw+transmitter&aq=f&aqi=g4&aql=&gs_sm=3&gs_upl=2720l7759l0l7955l16l13l0l1l1l1l835l5835l3-1.3.2.4l10l0&gs_l=hp.3..0l4.2720l7759l0l7955l16l13l0l1l1l1l835l5835l3-1j3j2j4l10l0&pbx=1&bav=on.2,or.r_gc.r_pw.r_qf.,cf.osb&fp=49539220ccf7de09&biw=1033&bih=768

Have a look and make a few calls, I'm sure you will find something suitable.

dekili
2012-03-12, 06:22 PM
Hi,

Maybe you can check what Agilent and Rohde & schwarz are offering. They do have CW transmitters and those where you can purchase s/w modules for different types of signals. In that way you could have different technologies. usual scenario for propagation model calibration is using CW transmitter but I am not sure about the otjer technologies. CW transmitter will help you in detecting potential coverage problems and will let you calibrate your propagation model. Agilent and R&S mightbe more expensive to some unknown manufecturers but they had proved themselves in the area of measuring equipment (that is why I recommend them).
Cheers.

rishi
2012-03-14, 01:30 AM
It is nothing but a transmitter attached to a indooor antenna planned at a point during a survey and after planting test transmitter we need to check it similar like a sigle antenna coverage which can be done on handy.

indoor
2012-03-15, 07:32 PM
The only GSM BCCH transmitters I know of these days are from Rohde & Schwarz and DRTi. Both will be expensive. If you want something cheap and durable I would look at the Consultix equipment. They also do the same transmitter with WCDMA capability. website is www.consultix-egypt.com And if you need something to measure CW they do receivers and collection software.

Rotorhead
2012-03-16, 03:25 AM
It is nothing but a transmitter attached to a indooor antenna planned at a point during a survey and after planting test transmitter we need to check it similar like a sigle antenna coverage which can be done on handy.

I did some pretty extensive testing for IBC in Sydney airport some years ago, as a general rule you can expect 40m radius from each antenne in a hybrid system.

pTroll
2012-03-20, 09:29 PM
Hi,

Thank You all for helping me.
I have looked at DRTi, but I expect it to be too expensive for me - lots of features there... I don't realy need an option to control transmitter via Wi-Fi link.
Consultix seems attractive to me. Drawback is that their products do not offer option to program BCCH.
Although UMTS is more robust against frequency selective fading, CPICH on UMTS900 should attenuate +/-the same as BCCH in GSM, so I think I will be going for 900/1800/2100 unit with ability to program CPICH. Each time I switch transmitter "on" every call in 100m radius will be dropped :D