A CORDIC-based digital quadrature mixer: comparison with a ROM-based architecture

This paper describes a CORDIC-based digital quadrature mixer in comparison with a ROM-based architecture. This architecture employs the circular rotation mode of the CORDIC algorithm for signal mixing as well as carrier generation, while the ROM-based architecture requires an additional complex multiplier for signal mixing. To optimize the hardware design parameters, the finite word-length effects of two implementation architectures are analyzed numerically. In addition, the simulation-based word-length determination is also conducted for the application to QPSK and QAM demodulators. The hardware costs of them are estimated, which shows that the CORDIC-based architecture occupies only a third of the area of the ROM-based architecture.