[GSM Receiver] using OpenBSC as a GSM Receiver

hi I am new to the list, I am a phd student in the area of verification of security protocol, so not exactly a hacker or tech guru. Anyway, I am interested in using the OpenBSC to analyze GSM protocol messages. I don't want to decode them or do anything fancy, I am mainly interested in what it is sent in clear. Is it possible to use the OpenBSC architecture to capture GSM messages and later analyze them using wireshark? I know this is possible using the USRP, but I would like to use OpenBSC. Anyway is there any particular reason why you are not supporting the USRP? Thanks