Low-power signal component separator for a 64-QAM 802.11 LINC transmitter

A LINC transmitter provides linear amplification while employing two nonlinear high-efficiency power amplifiers. This work proposes a LINC architecture where the two constant-envelope components of the signal are separated in the baseband analog domain. The signal component separator can achieve a power consumption which is significantly lower than conventional digital implementations. A signal component separator for 64-QAM 802.11a/g Wireless LANs is implemented in a 0.25-mu m CMOS process, the circuit occupies less than 0.1 mm(2) and consumes 45 mW from the 2.5-V supply. The measured EVM, ACPR, and alternate-ACPR of the recombined signal components are -37.6 dB, -34.9 dB and -47.0 dB, respectively.