A 1024-QAM Analog Front-End for Broadband Powerline Communication Up to 60 MHz

A high performance analog front-end (AFE) for broadband powerline communication between 1.6 and 60 MHz is presented. The frequency division multiplexing AFE supports optimum channel selection, avoids disturbing RF signals and allows co-existence with other users of the spectrum. The direct-conversion receiver operates linearly up to a + 18 dBm input level. Tunable low-pass filters, integrated into the receive path, support a wide class of service requirements by channel bandwidth selection. The dynamic range is 99.5 dB for 2 MHz channels, and 90.5 dB for 16 MHz channels. Error vector magnitude measurements are presented for a single-carrier 1024-QAM and a 1024-carrier 64-QAM signal as function of frequency and channel attenuation. For 1024-QAM, the error vector magnitude (EVM) is below or equal to 1.2% rms up to 60 dB of attenuation, whereas the 1024-carrier 64-QAM performs well up to 80 dB of attenuation. The presented chip was fabricated in a 0.25 mum SiGe BiCMOS process, and the measured power consumption from a single 2.5 V supply is 668 mW.