We used this functionality during development to play back a file containing the results of our MATLAB simulation. We used MATLAB to explore a variety of algorithms and methods until we identified one that handled the disparate data rates and that our engineers could implement efficiently on an FPGA.Īs an additional debugging and verification step, we can generate a signal from our MATLAB model and then broadcast it to a receiver using the RF Player in the URT. The bigger challenge was that the sampling rate we chose had to be high enough to yield a quality signal but not so high that we could not implement it in real time on the FPGA. We had to identify a sampling rate that would enable the terrestrial and satellite signals to be combined and synchronized. However, the two standards use different data rates for these signals, and the rates are not integral multiples of each other. XM and Sirius complement their satellite broadcasts with terrestrial broadcasts to provide coverage in both rural and urban settings. Handling the different data rates used in satellite and terrestrial broadcasting presented another optimization challenge. In MATLAB, we ran multiple simulations using different combinations of filter coefficients until we identified a set that would fit easily on the FPGA and meet the system's performance requirements. In practice, however, implementation on our FPGA required us to limit the filter to relatively few coefficients. MATLAB lets us design a filter with as many filter tap coefficients as needed to produce an almost perfect signal. Once we had verified the system's basic functionality, we began optimizing it for deployment on a low-cost FPGA. As we developed the algorithms and tested new ideas, we created power spectral density plots in MATLAB to visualize the intermediate results and the final output. Using built-in functions in MATLAB, Communications System Toolbox ™, and Signal Processing Toolbox ™ we quickly developed algorithms for these components without having to code in C. Both generators also required similar filtering, waveform generation, and upconversion components. The Sirius and XM multibeam generators that we were creating required similar modulation components, including differential quadrature phase-shift keying (DQPSK) and coded orthogonal frequency division multiplexing (COFDM) schemes. We could then use the MATLAB simulation results as a reference to verify the FPGA implementation. The key to accelerating development was to design, debug, and optimize our algorithms in MATLAB before implementing them in hardware. We used our MATLAB simulation results to verify the FPGA implementation, giving us confidence in our production hardware. This workflow enabled us to verify our design before deploying it to an FPGA. We wrote, debugged, optimized, and tested the core URT algorithms for the XM and Sirius standards in MATLAB ®. Engineers can easily update the URT to support additional protocols as testing needs change or new standards emerge. The Averna Universal Receiver Test (URT) platform is a software-defined radio frequency (RF) signal source that lets manufacturers test their devices against a range of standards using a single, integrated platform. This test setup is not only expensive it is also inconvenient for the engineers, who must configure multiple test environments and switch between them to test different protocols. To test their receivers, manufacturers often require several costly hardware platforms, one for each standard supported. Today's receivers must support XM, Sirius, Digital Audio Broadcasting (DAB), HD Radio, Radio Data System (RDS), Global Positioning System (GPS) protocols, and a wide variety of other broadcast and navigation standards. In spite of the name, this tuner only connects you to the XM network.Digital radio is rapidly establishing a foothold in the market, placing new demands on receiver manufacturers. Sirius and XM are similar, but separate satellite radio networks that are owned by the same company: “SiriusXM”. No special interface required, just plugs into the back of the stereo. IMPORTANT NOT compatible with “Sirius ready”, “XM ready” or “SAT ready” stereos. Also compatible with stereos requiring SXV200 or SXV100 receiversĪn automotive type satellite antenna is included, but for marine applications you may want a marine satellite radio antenna such as SRA-50 sold separately SiriusXM tuner kit for all brands of SiriusXM ready stereos.
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