WiMAX MIMO Transceiver Improves Receiver SNR May 02, 2008
The MAX2839, reportedly the industry's first single-chip, 2.3- to 2.7-GHz, WiMAX MIMO RF transceiver in high-volume production, relies on a dual-receiver architecture to mitigate RF channel fading, thereby increasing SNR by as much as 10 dB when compared to a single-receiver architecture. The two receivers feature a noise figure of 2.3 dB, a -81-dBm sensitivity for a 64-QAM signal at 5-MHz channel bandwidth, and a 95-dB gain control range that is digitally controllable in 1-dB steps. Factory calibrated to achieve better than -35-dB EVM, -45 dBc of sideband suppression, and a carrier leakage of -40 dBc without dc-offset correction, the receivers promise to significantly simplify integration with the digital MAC/baseband IC. On the transmitter side, the MAX2839 specifies a digitally controllable, 62-dB gain control range and delivers a 0-dBm linear output with a 64-QAM signal, greater than -45 dBc of sideband suppression, and more than -36-dB EVM while meeting a -70-dBr spectral mask. Available in a 56-pin, 8 mm x 8 mm leadless TQFN package, pricing starts at $9.31 each/1,000. MAXIM INTEGRATED PRODUCTS, Sunnyvale, CA. (800) 998-8800.
