Digital RF Processor (DRP) for Mobile Phones

RF circuits for wireless applications have recently migrated to low-cost digital nanoscale CMOS processes, which are optimized for digital logic and SRAM memory, but are unfriendly for conventional analog and RF designs. We present fundamental techniques, recently developed for wireless RF transceivers, that transform the RF and analog circuit design complexities into the digital domain, where it may benefit from the process node scaling and the design automation environment. The all-digital phase locked loop, the all-digital control of phase and amplitude of a polar transmitter, and the direct RF sampling techniques in the receiver allow great flexibility in reconfigurable radio design. The ideas presented have been realized in several commercial digital RF processors offered by Texas Instruments, including single-chip Bluetooth and GSM radios.