Background The potential for academic community partnerships are challenged in places where there is a history of conflict and mistrust. Addressing Disparities in Asian Populations through Translational Research (ADAPT) represents an academic community partnership between researchers and clinicians from Tufts Medical Center and Tufts University and community partners from Boston Chinatown. Based in principles of community-based participatory research and partnership research, this partnership is seeking to build a trusting relationship between Tufts and Boston Chinatown. Objectives This case study aims to provides a narrative story of the development and formation of ADAPT as well as discuss challenges to its future viability. Methods Using case study research tools, this study draws upon a variety of data sources including interviews, program evaluation data and documents. Results Several contextual factors laid the foundation for ADAPT. Weaving these factors together helped to create synergy and led to ADAPT’s formation. In its first year, ADAPT has conducted formative research, piloted an educational program for community partners and held stakeholder forums to build a broad base of support. Conclusions ADAPT recognizes that long term sustainability requires bringing multiple stakeholders to the table even before a funding opportunity is released and attempting to build a diversified funding base.

In this paper, a new digitally driven two input continuous mode Doherty power amplifier (DPA) architecture is proposed along with an analytical-based generic output combiner network design methodology. The load combiner provides the designer a choice to meet the optimum performance for any arbitrary back-off as well as for saturation. The PA's performance is further optimized with digital input splitting. To verify the proposed theory, a 20-W symmetrical continuous mode DPA is designed using 10-W GaN HEMTs. The proposed amplifier shows a drain efficiency between 56.0% and 75.4% at 41.4-44.6 dBm saturation power and between 45% and 56.5% at 35.7-38.5 dBm output power corresponding to 6-dB backoff. This performance is achieved over the band from 1.25 to 2.3 GHz that corresponds to 59.15% fractional bandwidth. The proposed hybrid analog/digital continuous mode DPA prototype is implemented using fieldprogrammable gate array (FPGA)/DSP platform and qualifies the spectral mask when excited by a modulated long term evolution signal along with digital predistortion.INDEX TERMS Broadband DPA, digital phase compensation, continuous mode, high efficiency, back-off.

This article explores a design space for bandwidth enhancement of two‐stage Doherty power amplifier for higher back‐off based on same devices. This design space analysis shows that for any back‐off level, a number of bandwidth enhancement solutions can be obtained with various combinations of design parameters for load combiner and load impedance. Therefore, the proposed scheme explores design space in terms of optimum design parameters for load combiner and load impedance for best bandwidth and realizability at a high back‐off. The proposed design methodology is validated with a two‐stage Doherty power amplifier using 25 W packaged Gallium Nitride High Electron Mobility Transistors. This Doherty power amplifier provides measured drain efficiency between 66% to 73.8% at saturation and 45% to 63.6% at 8‐9 dB output power back‐off from 1.7 to 2.025 GHz. Measurement with WCDMA signals shows that the adjacent channel power ratio is better than −46 dBc after applying digital predistortion.

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