Novel Silicon-on-Insulator SP5T Switch-LNA Front-end IC Enabling Concurrent Dual-band 256-QAM 802.11ac WLAN Radio Operations

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  • Author: Chun-Wen Paul Huang, Joe Soricelli, Lui Lam, Mark Doherty, Phil Antognetti, and William Vaillancourt
An innovative SOI SP5T switch-LNA integrated circuit is presented. The switch LNA consists of a diplexer that provides out-of-band rejection and enables dual-band concurrent operation, a dual-band LNA with bypass attenuators, and three high linearity transmit paths. Tx paths feature 0.1 dB compression at > 33 dBm input power, with > 35 dB Tx to Rx isolation, and 0.8 and 1.2 dB insertion loss for low and high bands respectively. Receive paths feature 12 dB gain with 2.5-2.8 dB NF. Cascading the design with a dual-band WLAN PA, a complex dual-band front-end module can be easily constructed in a 3 x 4 mm package, which demonstrates transmit and receive LNA linearity with EVM < 2% at >16 dBm and > - 5dBm output power respectively and compliant with the linearity requirements of the 802.11ac standard up to of 256-QAM 80 MHz operations. Index Terms — Dual-Band WLAN/MIMO/802.11ac frontend ICs, switch designs, LNA designs, WLAN front-end module.