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Base station (BTS) RF front-end design has in the past put more emphasis on performance compared to cost and size. However, to meet the evolving needs of the wireless infrastructure industry, BTS designers today are facing more challenges. Achieving the desired RF performance is only part of the equation for today's BTS RF front-end design. At the same time, cost is also a critical consideration to maintain competitiveness in handling escalating pricing pressure. More channels are now required to fit into a transmit/receive (Tx/Rx) card, which leads to PCB real estate becoming another key factor for BTS designers. In addition, the time to market has condensed, so design cycle time is a critical consideration for BTS RF front-end design.

A critical design consideration for BTS receiver RF front-end design is selecting an appropriate low noise amplifier (LNA) to address all the new design challenges mentioned above. With the release of the MGA-633P8 ultra low noise, high linearity active bias low noise amplifier, Avago Technologies has provided an optimal solution. The MGA-633P8 has superior RF performance achieved through the use of the company's proprietary 0.25 μm GaAs enhancement-mode PHEMT process, with an optimum operating frequency range of 450 to 2000 MHz. Similar to Avago's former MGA-631P8 and MGA-632P8 active bias LNA series, the MGA-633P8 is housed in the same industrial standard miniature 2.0 x 2.0 x 0.75 mm surface-mount 8-lead QFN package. The MGA-633P8 is targeted as the single-ended or balanced first-stage LNA for various cellular base station applications, such as transceiver radio cards, tower mounted amplifiers (TMA), combiners, repeaters and remote/digital radio heads.

Receiver sensitivity is one of the most critical requirements for BTS receive path design. This is especially important with the recent development of the wireless infrastructure industry, where providing optimum coverage with the best signal quality is highly desirable. A proper selection of the LNA, in particular the first-stage LNA that greatly affects the BTS receiver sensitivity performance, is required. At 900 MHz, the superior noise figure of 0.37 dB and gain of 18 dB, the MGA-633P8 is one of the best candidates to offer superior receiver sensitivity performance for today's BTS design (see Figure 1). The MGA-633P8 is best suited to both single-ended and balanced configuration applications.