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Hello I am working with USRP and GNSS Test Toolkit 3.0 to generate GNSS signals. As I transmit the simulated signal through the USRP, I have difficulty getting anything on my GNSS device(no satellites visible/no location fix). What might be wrong, especially about the generation parameters/configuration? What should be the TX power level? Are there any other aspects that I need to consider? Description of hardware setup: I am using NI USRP-2974 with the default streaming project, where I read the GNSS binary file created using GNSS toolkit 3.0 and transmit the IQs at a rate of 10MS/s (read from the binary file) at a center frequency of 1602 MHz using an omni antenna which is appropriate for the L band. All other USRP TX settings are at default values. I have tried attenuators ranging from -50 dB to -90 dB. My GNSS receiver/test device is a surveying GNSS tablet with a GNSS antenna. Configuration of the GNSS test toolkit: I have used niGLONASS Write Waveform to File (Simple, Automatic Mode).vi from the GNSS toolkit 3.0 with the default values (including the almanac and ephemeris files provided with the toolkit) I will be looking forward to hearing from you. Best regards,

I've got a stream reader endpoint, and I'm trying to avoid waiting for a timeout from the reader endpoint creation. Do you have to wait until the writer end is created before you can create the reader end? The LabVIEW help says that both are needed, obviously, but doesn't explicitly state precedence or a requirement that they be created at the same time. Never mind. I see from reading http://www.ni.com/white-paper/12267/en that "The endpoint that is created first will wait until the other endpoint has been created and is ready to connect, at which point both create functions will exit. The stream is then ready to transfer data. Used in this manner, the create function effectively acts as a network rendezvous where neither create function will progress until both sides of the stream are ready or until the create call times out." This raises a different question, now. If these endpoint attempts are preventing my program from exiting, is it possible to force them to stop before their timeout? Perhaps I'll just put them in loops with short timeouts and made the loops aware of my exit conditions. Ryan R.