I know this may due to stupid reasons while I have no idea how to achieve it.
Ubuntu 13.04(32-bit); gnuradio-3.6.5; GNU C++ version 4.7.3; Boost_105300; UHD_003.005.004-154-ge6a1de6d; USRP N210; RFX2400
There are two Wi-Fi APs in our lab with 802.11g and 802.11n standard. I use a simple software "wavemon" to get their information about channel and signal strength.
I use four antennas for test. Two are official VERT2400, others are 2.4G antennas. I use the given example "uhd_fft.grc" (a simple FFT block) hoping to observe frequency spectrum of Wi-Fi signal. No matter what antenna I set up (even without antenna) and what central frequency I tune, the FFT window only shows something like noise around -50--60dB on whole spectrum (sample rate=25M) which is unlike the 802.11 standard.
There is low possibility of bad hardware I guess. I doubt that there may be some problems with my test methods and hope for some advice.
Thanks!