I am working with an NI-2901 USRP device within LabVIEW Communications Suite 2015. The USRP is connected via USB to a 3.20GHz quad core with 8.00GB of RAM. I am trying to generate a chirp signal that is about 10MHz(give or take a few MHz) for a radar project. Obviously, a chirp with this high of a frequency range requires a sampling frequency greater than 10MHz.
My issue is the common underflow problem whenever I increase my sampling rate rate beyond 2MHz. I have learned that the common cure for this problem is to implement a Consumer-Producer model with queues. Attached is my Tx program that generates the chirp via code. This is then sent to an enqueue loop. I have the USRP Tx process pull off the data from a dequeue loop. This results in errors regarding an underflow.
What I believe may be the issue is that my producer is running slower than the Tx consumer loop whenever I increase my sampling rate beyond 2MHz. Is there any way to work around this limitation? Is my PC really a bottleneck(which I cannot say is a poor performing E-Machine)? Is my goal of generating a chirp signal with this high of a frequency impossible with my current gear?
