A fully-integrated reconfigurable dual-band transceiver for short range wireless communication in 180nm CMOS

A fully-integrated reconfigurable dual-band transceiver (TRX) is presented for short range wireless communication. The TRX has two independent RF front-ends for each band with a shared analog baseband to achieve optimum power and cost. In Sub-GHz (760–960MHz) band, the maximum 75dBc 3 rd harmonic rejection ratio (HRR) is achieved by inserting a RFA with notch filtering. In 2.4GHz band, a single-ended-to-differential (S2D) RFA with phase and gain error compensation is proposed. By optimizing two bands separately, the RX achieves a NF of 5.1dB and 4.2dB, respectively. A ∑-Δ fractional-N PLL with two switchable Class-C VCOs is employed to provide the LOs. Moreover, the multi-mode CMOS PAs are integrated, which achieve the measured output P1dB (OP1dB) of 16.3dBm and 14.8dBm with 25% PAE for Sub-GHz and 2.4GHz bands. Furthermore, to optimize the PA's back-off efficiency, the power-control loop is proposed to detect the input signal PAPR in real time and flexibly reconfigure the PA's operation modes. With this proposed technique, the PAE in Sub-GHz band is improved by ×3.24 and ×1.41 at 9dB and 3dB back-off powers. In 2.4GHz band, the PAE is improved by ×2.17 at 6dB back-off power. The measured results have demonstrated that this presented transceiver has achieved comparable or even better performance in terms of noise, HRR, OP1dB and power efficiency compared with the-state-of-the-arts.