A 40nm 4-downlink and 2-uplink RF Transceiver Supporting LTE-Advanced Carrier Aggregation

A multi-band multi-mode LTE-Advanced (LTE-A) transceiver is demonstrated in this paper. There are 4 receivers (RX) to support inter-band and intra-band downlink (DL) carrier aggregation (CA) with 256QAM modulation. The RX noise figure (NF) is better than 2.5 dB for RF frequencies < 2.7 GHz and the NF is 3.5 dB in the 5 GHz band. In addition, there are two transmitters (TX) to support inter-band and intra-band uplink (UL) CA with 64QAM modulation. The TX EVM is 1.59% in the 3.5 GHz band. The system architecture and circuit techniques to overcome the 4RX/2TX CA spurs and interferences are described in this paper. It is shown that there is no unwanted CA spur in the signal bandwidth.