A Highly Linear Receiver Using Parallel Preselect Filter for 5G Microcell Base Station Applications

By introducing three different techniques, this article, for the first time, presents a wideband highly linear receiver (RX) capable of handling blocking scenarios in fifth-generation (5G) microcell base station applications. First, a parallel preselect filter is introduced to satisfy the base station co-location blocking requirements. Next, a combination of third-order RF and baseband (BB) filters is adopted to attenuate close-in blockers by a −120 dB/dec roll-off. Finally, a translational feedback network is proposed to reduce the in-band gain ripple to below 0.5 dB and provide better than −19 dB input matching. Fabricated in the 40-nm CMOS technology, the proposed RX occupies a core area of 0.8 $\mathrm {\mathbf {mm^{2}}}$ and consumes 108–176 mW from a 1.3 V supply over the RX’s 0.5–3-GHz operating frequency. It achieves a 3-dB bandwidth of 150 MHz and a noise figure (NF) of 2.6–3.9 dB over the RX frequency range. Activating the parallel preselect filter degrades the NF by as little as 1.2 dB in the worst case. The RX shows a $\geq $ 97.5% throughput when receiving a 100-MS/s quadrature phase shift keying (QPSK) signal with 7.5-dB SNR and achieves a −9.7 dB error vector magnitude (EVM) while facing a −15 dBm continuous-wave (CW) blocker only 20 MHz away from the desired 100-MS/s QPSK signal with 12.3-dB SNR, thus satisfying the 3rd generation partnership project (3GPP) requirements with sufficient margin.