Looking for some hardware to learn about SDR? This project may be just what you need to explore this hot topic!
This article describes the design and the theory of operation of an HF radio receiver operating in the 3.5 to 18 MHz range. The receiver architecture is based on software defined radio techniques and incorporates a Cypress PSoC CY8C3866 device that contains both analog and digital circuits, thus decreasing the receiver's component count. This part is far more than just a microcomputer; it also contains software configurable analog and digital peripherals on a single chip. Cypress calls the family a PSoC in reference to it being a programmable embedded system-on-chip. The newest series of parts, which Cypress calls the PSoC 3 family, contains a 67 MHz 8051 class microcomputer, an analog to digital converter fast enough and with enough resolution for an SDR receiver, and other valuable functions that are desirable in a receiver design.
The receiver should be used for casual, conversational listening; it is not intended as a higher performance receiver for DX use. It was designed to use a minimum number of components, to be physically small and easy to operate. An LCD and controls to select the frequency and modes of operations were considered, but the design would have fewer parts and cost less if a personal computer (PC) is used for all user control. Since the PSoC has a USB port, the receiver can connect to the PC with a USB cable and take power from the PC over the USB cable, saving a power jack, and external power source. Control of the receiver is accomplished by having the receiver USB port appear as a standard com port to the PC. The Ham Radio Deluxe (HRD) program works perfectly to control this receiver.
The March/April 2012 issue of the American Radio Relay League QEX magazine contains an article describing the updated receiver design.
If you are interested in purchasing this receiver: