Antenna/Amplifier for BladeRF for GSM Application

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JedNamara
Posts: 2
Joined: Sat Sep 06, 2014 9:59 pm

Antenna/Amplifier for BladeRF for GSM Application

Post by JedNamara » Mon Sep 15, 2014 8:19 am

Has anyone tried amplifying the send and receive of BladeRF for GSM (800/900/1800/2100MHz) applications? Its 4mW (based on posting in forums) is very low - not reaching beyond a few feet in the test lab.

I have contacted companies with products like
http://3gstore.com/product/5015_cellpho ... tenna.html and they hesitate to say it would work with BladeRF because they have never had a customer with it before. They also raised a concern that because TX and RX are separate (unlike typical GSM equipment including mobile phones and modems), then each may require a separate amplifier each with its own antenna - but that positioning amplifiers less than 10 ft apart could create interference. One suggested connecting both the TX and RX to a splitter (under normal use, the 2 "OUT") so that they become a single connector (normally the "IN") that can then be connected to a single amplifier + antenna.

Unfortunately we do not have the funding to simply buy just to experiment - we would not want to purchase something that we could potentially just set aside for not working and moving on to the next amplifier.

Does anyone have experience on this? Thanks

White-Noise
Posts: 1
Joined: Tue Oct 21, 2014 11:54 pm
Location: Down-Under, Mate

Re: Antenna/Amplifier for BladeRF for GSM Application

Post by White-Noise » Fri Oct 24, 2014 2:24 am

Uncertain as to your specific limitations, surrounding the availability of funding for your project, but...

The fact that the BladeRF has independent ports for TX and RX is in fact a fact to your advantage, given the application at hand.
(Stand-alone GSM Base Station.)

An almost infinite number of outstanding examples of 850-950MHz High Gain Mono-Block Amplifiers, are up for grabs on places such as eBay.
Start your first track of attack towards say, any surplus Lucent KS21583 L9 Modules.

These offer a respectable gain of 40-45dB across the 850-950MHz GSM footprint, with a maximum output in the order of 250mW.

One of these correctly driven from your BladeRF - and then coupled to a suitable Antenna - should have you comfortably across any Neighbourhood Block, without any difficulty at all!
(However, don't be a Muppet - be aware of exactly what your obligations are, surrounding your 'questionable emissions' versus any FCC Permit/Licence requirements!)

These Lucent Modules are typically utilised as Mono-Block Pre-Amplifiers in Carrier or Enterprise Class deployments - and are used right before those High-Power Cellular Base Station Amplifier chains.
(The likes of which are also readily available as surplus. Shark-hunt for any number of Motorola Cellular Base Station PAs, such as Motorola Part Numbers SGTF1019A, SGTF1019B, SGTF1020B, SGTF1038A, SGTF1040A, SGTF1040B and STF2520A.)

These are all excellent examples, with most of these units capable of 150-300W of output power, some of which requiring only minuscule milli-watt levels of input drive!


Needless to say, (and short of engaging the use of a Cavity/Filter Array), you will obviously need to apply some form of separation from your now-amplified TX Chain, away from your RX Chain - but given the low price of quality unbalanced feeder these days, (read Coax...), this shouldn't pose too much of a problem.

Again, not sure of your project's funding limitations - but surely this is as good as a good start will get!

And with that, he recedes once again - back into the 'White-Noise'...

qin
Posts: 4
Joined: Tue Sep 27, 2016 4:18 am

Re: Antenna/Amplifier for BladeRF for GSM Application

Post by qin » Tue Sep 27, 2016 6:33 pm

Yes,The output of bladerf X40 is only 4 mW,but the USRP B200,USRP1,its is 100-200mW.the poor output limite GSM Application of BladeRF very much,really!
so we need Amplifier for BladeRF for GSM Application.
https://item.taobao.com/item.htm?id=536 ... oe4kid7475 this is small Amplifier with 8W output
https://item.taobao.com/item.htm?spm=20 ... a0&idnum=0 this is small Amplifier with 50W output,
and 60W,70W,what,you need more output ,100W and 200W is also available

qin
Posts: 4
Joined: Tue Sep 27, 2016 4:18 am

Re: Antenna/Amplifier for BladeRF for GSM Application

Post by qin » Tue Sep 27, 2016 6:36 pm

I buy a 8W Amplifier ,It is on the delivery way,I will try it,and tell you the result.

qin
Posts: 4
Joined: Tue Sep 27, 2016 4:18 am

Re: Antenna/Amplifier for BladeRF for GSM Application

Post by qin » Fri Sep 30, 2016 8:40 pm

My 8W Amplifier work good with bladeRf X40,really.
it need DC24V and a good Antenna,the gsm signal can be found around 100 meters ,good. :D

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