I specifically mean patents for the "generalized" accelerator hardware implemented in silicon that would presumably be needed to make a specialty FPGA that's fast enough to handle modern RF modulations, even in a vaguely software-defined way. That's presumably companies like Qualcomm's secret sauce, and you can bet they have it locked down with patents and NDAs. If someone came up with a general purpose CPU powerful enough to actually do everything fast enough purely in software, then that might be different (but would likely have plenty of its own patent issues!)