receive GSM signals using USRP 2920

[dana.nemes]

Can you tell me, please, where I can find this example?

Thank you!!

[MHantera]

Which examples ???

[dana.nemes]

This one with the cognitive radio with GSM signals.I'm using USRP 2932 and I want to try this example if you can send it to me.

Thank you!

[MHantera]

unfortunately  i didn't reach any thing related to measure the power in gsm band 

but if you are working in making a cognitive radio in gsm band "same project as mine" we could work together.

[ketaki2511]

hello, i am also working on cognitive radio in 2.4 GHz band..using energy detection method. i am facing a problem with a threshold.how to set a threshold? how is it calculated?transmission and reception is taking place accurately and if some frequency channel is vacant then how can the secondary user be transferred to that channel from other frequency channel?

[PeanutButterOven]

Hello ketaki2511,

Are you using the Cognitive Radio Library (linked below)? It appears that there is a function in the CR Library that does this calculation.

https://decibel.ni.com/content/docs/DOC-29494 

[ketaki2511]

hello sir, thank you so much..but i could not find any content on the link..i guess its been deleted. sir, i have already decided the threshold but if some noise comes then at time signal power can go below thresold and we might think that signal is not present but actually it is present..so at that time i have to set lower and upper threshold..i dont know how to set it ..i mean how to code for it..do you know some other parameters which can decide whether chnnel is vacant or not..signal power is one parameter..do you know others.

[PeanutButterOven]

I apologize for the broken links. I have attached the library I was speaking of. Also if you go to this link https://decibel.ni.com/content/docs/DOC-29494 you may find useful information as it is NI's USRP group forum. The Cognitive Radio Library can be found there.

I do not know of any of any other channel estimation schemes other than spectral power. I was under the impression that when implementing channel estimation upper and lower boundary limits were inherently necessary for logic decisions.  

[ketaki2511]

can u tell me how reliable is the energy detection method? what are its drawbacks?

[hantera]

Hello , First i want to tell you that i had made a proj similar to you the last year i've achived all the 4 stages of cog. radio "sensing , sharing , Hopping, Evacuating " so if you wants any help let me know my facebook account is mohamed hantera .

in the other hand there are alot of drawbacks in energy detection here are the most common two
 
1-False alarm 

2-Miss detection

for any other info let me know