Multiple communication protocols for software defined radio

We present an inexpensive multi-protocol communication system implemented entirely in software comprised of Global Positioning System (GPS), Wireless Local Area Network (WLAN) and Bluetooth (BT). All three communications protocols share the same Analog to Digital converter and are sampled at the same hardware sampling rate. The hardware sampling clock is provided by a high stability crystal oscillator at a sampling frequency suited for the GPS receiver. For the WLAN and BT systems, the sampling rate is modified with an interpolation filter and a Phase Lock Loop (PLL) both implemented in software. The communication system is able to execute simultaneously in software the physical layer processing and data sample timing for GPS, WLAN, and BT employing Sandbridge Technologies´ multithreaded Sandblaster SB9600 Processor.